Albert Wegener

A block-oriented lossless decompressor is used to decode encoded data fetched from storage that is subsequently transferred across a network in encoded (compressed) form. In examples described herein, applications executing at network nodes send GET requests, or similar messages, to storage systems, which can return compressed data this is decompressed in an intermediate node (between the storage node and the app), and can return compressed data that is decoded in the same network node in which… Show more

A block-oriented lossless decompressor is used to decode encoded data fetched from storage that is subsequently transferred across a network in encoded (compressed) form. In examples described herein, applications executing at network nodes send GET requests, or similar messages, to storage systems, which can return compressed data this is decompressed in an intermediate node (between the storage node and the app), and can return compressed data that is decoded in the same network node in which the requesting application is running. Show less

A combination of a block-oriented encoder and decoder with a modified dataset identifier that is associated with an encoded block size are used to perform block-based encoding and decoding operations. The encoding process may generate optional metadata that includes an array of encoded block sizes to support random access into the stream or group of encoded blocks during the decoding process. The modified dataset identifier associates the original dataset identifier with the block size used by… Show more

A combination of a block-oriented encoder and decoder with a modified dataset identifier that is associated with an encoded block size are used to perform block-based encoding and decoding operations. The encoding process may generate optional metadata that includes an array of encoded block sizes to support random access into the stream or group of encoded blocks during the decoding process. The modified dataset identifier associates the original dataset identifier with the block size used by the encoder. Show less

A wearable computing device, such as a wearable credit card type device or a wearable identification type device, that provides for deferred re-authentication that a user currently in possession of the wearable computing device is indeed the authorized user. In this aspect, the wearable computing device may store authentication data input by the user when network connection is unavailable, and transmit the authentication data when the network becomes available. For increased security, location… Show more

A wearable computing device, such as a wearable credit card type device or a wearable identification type device, that provides for deferred re-authentication that a user currently in possession of the wearable computing device is indeed the authorized user. In this aspect, the wearable computing device may store authentication data input by the user when network connection is unavailable, and transmit the authentication data when the network becomes available. For increased security, location information may also be incorporated so that the re-authentication may only occur within a limited number of geographic locations. Show less

Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to decompress integer or… Show more

Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to decompress integer or floating-point waveform data. At the memory controller, a configurable compressor compresses integer or floating-point waveform data for transfer to off-chip memory in compressed packets and a configurable decompressor decompresses compressed packets received from the off-chip memory. Compression reduces the memory or storage required to retain waveform data in a semiconductor or magnetic memory. Compression reduces both the latency and the bandwidth required to exchange waveform data. Show less

An execution unit configured for compression and decompression of numerical data utilizing single instruction, multiple data (SIMD) instructions is described. The numerical data includes integer and floating-point samples. Compression supports three encoding modes: lossless, fixed-rate, and fixed-quality. SIMD instructions for compression operations may include attenuation, derivative calculations, bit packing to form compressed packets, header generation for the packets, and packed array… Show more

An execution unit configured for compression and decompression of numerical data utilizing single instruction, multiple data (SIMD) instructions is described. The numerical data includes integer and floating-point samples. Compression supports three encoding modes: lossless, fixed-rate, and fixed-quality. SIMD instructions for compression operations may include attenuation, derivative calculations, bit packing to form compressed packets, header generation for the packets, and packed array output operations. SIMD instructions for decompression may include packed array input operations, header recovery, decoder control, bit unpacking, integration, and amplification. Compression and decompression may be implemented in a microprocessor, digital signal processor, field-programmable gate array, application-specific integrated circuit, system-on-chip, or graphics processor, using SIMD instructions. Compression and decompression of numerical data can reduce memory, networking, and storage bottlenecks. Show less

Compression and decompression of numerical data utilizing single instruction, multiple data (SIMD) instructions is described. The numerical data includes integer and floating-point samples. Compression supports three encoding modes: lossless, fixed-rate, and fixed-quality. SIMD instructions for compression operations may include attenuation, derivative calculations, bit packing to form compressed packets, header generation for the packets, and packed array output operations. SIMD instructions… Show more

Compression and decompression of numerical data utilizing single instruction, multiple data (SIMD) instructions is described. The numerical data includes integer and floating-point samples. Compression supports three encoding modes: lossless, fixed-rate, and fixed-quality. SIMD instructions for compression operations may include attenuation, derivative calculations, bit packing to form compressed packets, header generation for the packets, and packed array output operations. SIMD instructions for decompression may include packed array input operations, header recovery, decoder control, bit unpacking, integration, and amplification. Compression and decompression may be implemented in a microprocessor, digital signal processor, field-programmable gate array, application-specific integrated circuit, system-on-chip, or graphics processor, using SIMD instructions. Compression and decompression of numerical data can reduce memory, networking, and storage bottlenecks. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then decompressed prior to normal signal processing. For the downlink, the baseband processor compresses baseband signal samples and transfers the compressed signal samples to the RF unit. The RF unit decompresses the compressed samples prior to digital upconversion and digital to analog conversion to form an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including OBSAI or CPRI compliant systems. Show less

Memory system operations are extended for a data processor by an application programming interface API, including a set of operations and parameters for the operations, which provides for data compression and decompression during or in conjunction with processes for moving data between memory elements of the memory system. The set of operations can be configured to use the parameters and perform the operations of the API. The API can support moves between memory having a first access latency… Show more

Memory system operations are extended for a data processor by an application programming interface API, including a set of operations and parameters for the operations, which provides for data compression and decompression during or in conjunction with processes for moving data between memory elements of the memory system. The set of operations can be configured to use the parameters and perform the operations of the API. The API can support moves between memory having a first access latency, such as memory integrated on the same chip as a processor core, and memory having a second access latency that is longer than the first access latency, such as memory on a different integrated circuit than the processor core. Show less

A method and apparatus for determining one or more compression parameters suitable to compress a class of signals, may include inputting a test data set, being representative of a data set to be compressed, characterizing the test data, selecting a compression algorithm, calculating a distortion level to be used in determining the compression ratio (or a compression ratio to be used in determining the distortion level), generating a computer implemented model for the test data, selecting a… Show more

A method and apparatus for determining one or more compression parameters suitable to compress a class of signals, may include inputting a test data set, being representative of a data set to be compressed, characterizing the test data, selecting a compression algorithm, calculating a distortion level to be used in determining the compression ratio (or a compression ratio to be used in determining the distortion level), generating a computer implemented model for the test data, selecting a recommended operating point based on a computer implemented model, and determining compression parameters corresponding to the operating point. The compression parameters may subsequently be applied for configuration of compression applied to one or more production data sets that are similar to the test data. Show less

Compression and decompression of numerical data can apply to floating-point or integer samples. Floating-point samples are converted to integer samples and the integer samples are compressed and encoded to produce compressed data for compressed data packets. For decompression, the compressed data retrieved from compressed data packets are decompressed to produce decompressed integer samples. The decompressed integer samples may be converted to reconstruct floating-point samples. Adaptive… Show more

Compression and decompression of numerical data can apply to floating-point or integer samples. Floating-point samples are converted to integer samples and the integer samples are compressed and encoded to produce compressed data for compressed data packets. For decompression, the compressed data retrieved from compressed data packets are decompressed to produce decompressed integer samples. The decompressed integer samples may be converted to reconstruct floating-point samples. Adaptive architectures can be applied for integer compression and decompression using one or two FIFO buffers and one or two configurable adder/subtractors. Various parameters can adapt the operations of adaptive architectures as appropriate for different data characteristics. The parameters can be encoded for the compressed data packet. Show less

A raw format image representing an image received from an image capture device at an image data rate, can be compressed at least as fast as the image data rate (i.e. in real time) using compact and low cost components. The compressed image data can then be transferred across a chip-to-chip data channel to a memory system or to a host processor where it can be stored as compressed data. The host processor or other processor can read and decompress the compressed raw data and apply digital signal… Show more

A raw format image representing an image received from an image capture device at an image data rate, can be compressed at least as fast as the image data rate (i.e. in real time) using compact and low cost components. The compressed image data can then be transferred across a chip-to-chip data channel to a memory system or to a host processor where it can be stored as compressed data. The host processor or other processor can read and decompress the compressed raw data and apply digital signal processing including industry-standard data compression or other image processing algorithms to the recovered raw format image without being constrained to real-time processing. Show less

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are… Show more

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are retrieved from the mixed-data frames and provided to the air interface and LAN segment, respectively. For the uplink from the RE, the radio signal data from the air interface and the data packets from the LAN segment are mapped to mixed-data frames and transmitted to the gateway. The gateway retrieves the signal samples and data packets from the mixed-data frames for transfer to the REC and switch, respectively. Show less

Compression of floating-point numbers is realized by comparing the exponents of the floating-point numbers to one or more exponent thresholds to classify the floating-point numbers and to apply different compression types to the different classes. Each class and compression type is associated with an indicator. An indicator array contains M indicators for M floating-point numbers. The position of the indicator in the indicator array corresponds to one of the floating-point numbers and the… Show more

Compression of floating-point numbers is realized by comparing the exponents of the floating-point numbers to one or more exponent thresholds to classify the floating-point numbers and to apply different compression types to the different classes. Each class and compression type is associated with an indicator. An indicator array contains M indicators for M floating-point numbers. The position of the indicator in the indicator array corresponds to one of the floating-point numbers and the indicator value specifies the class and compression type. The floating-point number is encoded in accordance with the compression type for its class. A compressed data packet contains the indicator array and up to M encoded floating-point numbers. Decompression extracts the indicator array and the encoded floating-point numbers from the compressed data packet and decodes the encoded floating-point numbers in accordance with the compression type associated with the indicator value to form a reconstructed floating-point number. Show less

Memory system operations are extended for a data processor by DMA, cache, or memory controller to include a DMA descriptor, including a set of operations and parameters for the operations, which provides for data compression and decompression during or in conjunction with processes for moving data between memory elements of the memory system. The set of operations can be configured to use the parameters and perform the operations of the DMA, cache, or memory controller. The DMA, cache, or… Show more

Memory system operations are extended for a data processor by DMA, cache, or memory controller to include a DMA descriptor, including a set of operations and parameters for the operations, which provides for data compression and decompression during or in conjunction with processes for moving data between memory elements of the memory system. The set of operations can be configured to use the parameters and perform the operations of the DMA, cache, or memory controller. The DMA, cache, or memory controller can support moves between memory having a first access latency, such as memory integrated on the same chip as a processor core, and memory having a second access latency that is longer than the first access latency, such as memory on a different integrated circuit than the processor core. Show less

Compression of exponents, mantissas and signs of floating-point numbers is described. Differences between exponents are encoded by exponent tokens selected from a code table. The mantissa is encoded to a mantissa token having a length based on the exponent. The signs are encoded directly or are compressed to produce fewer sign tokens. The exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. Decompression decodes the exponent tokens using the code table. The… Show more

Compression of exponents, mantissas and signs of floating-point numbers is described. Differences between exponents are encoded by exponent tokens selected from a code table. The mantissa is encoded to a mantissa token having a length based on the exponent. The signs are encoded directly or are compressed to produce fewer sign tokens. The exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. Decompression decodes the exponent tokens using the code table. The decoded exponent difference is added to a previous reconstructed exponent to produce the reconstructed exponent. The reconstructed exponent is used to determine the length of the mantissa token. The mantissa token is decoded to form the reconstructed mantissa. The sign tokens provide the reconstructed signs or are decompressed to provide the reconstructed signs. The reconstructed sign, reconstructed exponent and reconstructed mantissa are combined to form a reconstructed floating-point number. Show less

Exponents, mantissas and signs of floating-point numbers are compressed in encoding groups. Differences between maximum exponents of encoding groups are encoded by exponent tokens selected from a code table. Each mantissa of an encoding group is encoded to a mantissa token having a length based on the maximum exponent. Signs are encoded directly or are compressed to produce sign tokens. Exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. For decompression… Show more

Exponents, mantissas and signs of floating-point numbers are compressed in encoding groups. Differences between maximum exponents of encoding groups are encoded by exponent tokens selected from a code table. Each mantissa of an encoding group is encoded to a mantissa token having a length based on the maximum exponent. Signs are encoded directly or are compressed to produce sign tokens. Exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. For decompression, the exponent tokens are decoded using the code table. The decoded exponent difference is added to a previous reconstructed maximum exponent to produce the reconstructed maximum exponent for the encoding group. The reconstructed maximum exponent is used to determine the length of the mantissa tokens that are decoded to produce the reconstructed mantissas for the encoding group. The reconstructed sign, reconstructed exponent and reconstructed mantissa are combined to form a reconstructed floating-point number. Show less

Compression of exponents, mantissas and signs of floating-point numbers is described. Differences between exponents are encoded by exponent tokens selected from a code table. The mantissa is encoded to a mantissa token having a length based on the exponent. The signs are encoded directly or are compressed to produce fewer sign tokens. The exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. Decompression decodes the exponent tokens using the code table. The… Show more

Compression of exponents, mantissas and signs of floating-point numbers is described. Differences between exponents are encoded by exponent tokens selected from a code table. The mantissa is encoded to a mantissa token having a length based on the exponent. The signs are encoded directly or are compressed to produce fewer sign tokens. The exponent tokens, mantissa tokens and sign tokens are packed in a compressed data packet. Decompression decodes the exponent tokens using the code table. The decoded exponent difference is added to a previous reconstructed exponent to produce the reconstructed exponent. The reconstructed exponent is used to determine the length of the mantissa token. The mantissa token is decoded to form the reconstructed mantissa. The sign tokens provide the reconstructed signs or are decompressed to provide the reconstructed signs. The reconstructed sign, reconstructed exponent and reconstructed mantissa are combined to form a reconstructed floating-point number. Show less

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens… Show more

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens. Exponent differences between consecutive exponent values may be encoded individually or jointly. The samples in the group are mapped to corresponding mantissas, each mantissa having a number of bits based on the exponent value. Removing LSBs depending on the exponent value produces mantissas having fewer bits. Feedback control monitors the compressed bit rate and/or a quality metric. Show less

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens… Show more

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens. Exponent differences between consecutive exponent values may be encoded individually or jointly. The samples in the group are mapped to corresponding mantissas, each mantissa having a number of bits based on the exponent value. Removing LSBs depending on the exponent value produces mantissas having fewer bits. Feedback control monitors the compressed bit rate and/or a quality metric. Show less

A method and an apparatus for an ultrasound system provide compression of ultrasound signal samples after analog to digital conversion and before beamforming. The analog ultrasound signals received from an array of ultrasound transducer elements are digitally sampled by a plurality of analog to digital converters (ADCs) to produce a plurality of sequences of signal samples. Each sequence of signal samples is compressed to form a corresponding sequence of compressed samples. The resulting… Show more

A method and an apparatus for an ultrasound system provide compression of ultrasound signal samples after analog to digital conversion and before beamforming. The analog ultrasound signals received from an array of ultrasound transducer elements are digitally sampled by a plurality of analog to digital converters (ADCs) to produce a plurality of sequences of signal samples. Each sequence of signal samples is compressed to form a corresponding sequence of compressed samples. The resulting sequences of compressed samples are transferred via a digital interface to an ultrasound signal processor. At the ultrasound signal processor, the received sequences of compressed samples are decompressed. The typical processing operations, such as beamforming, downconversion and detection, are applied to decompressed samples. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then decompressed prior to normal signal processing. For the downlink, the baseband processor compresses baseband signal samples and transfers the compressed signal samples to the RF unit. The RF unit decompresses the compressed samples prior to digital upconversion and digital to analog conversion to form an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including OBSAI or CPRI compliant systems. Show less

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are… Show more

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are retrieved from the mixed-data frames and provided to the air interface and LAN segment, respectively. For the uplink from the RE, the radio signal data from the air interface and the data packets from the LAN segment are mapped to mixed-data frames and transmitted to the gateway. The gateway retrieves the signal samples and data packets from the mixed-data frames for transfer to the REC and switch, respectively. Show less

Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to decompress integer or… Show more

Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to decompress integer or floating-point waveform data. At the memory controller, a configurable compressor compresses integer or floating-point waveform data for transfer to off-chip memory in compressed packets and a configurable decompressor decompresses compressed packets received from the off-chip memory. Compression reduces the memory or storage required to retain waveform data in a semiconductor or magnetic memory. Compression reduces both the latency and the bandwidth required to exchange waveform data. Show less

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and an interface between the stationary part and the rotatable part. The rotatable part includes an x-ray source, a sensor array for detecting x-rays passing through the object to produce projection data samples, a compressor that compresses the projection data samples and a storage device that stores the compressed samples. The storage device on the rotatable part can… Show more

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and an interface between the stationary part and the rotatable part. The rotatable part includes an x-ray source, a sensor array for detecting x-rays passing through the object to produce projection data samples, a compressor that compresses the projection data samples and a storage device that stores the compressed samples. The storage device on the rotatable part can include one or more solid state drives. For image reconstruction, the compressed samples are retrieved from the storage device, transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed samples and provides decompressed samples to the image reconstruction processor. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then decompressed prior to normal signal processing. For the downlink, the baseband processor compresses baseband signal samples and transfers the compressed signal samples to the RF unit. The RF unit decompresses the compressed samples prior to digital upconversion and digital to analog conversion to form an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including OBSAI or CPRI compliant systems. Show less

In an ultrasound imaging system that applies a beamformer to received ultrasound signal samples to form one or more beams represented by arrays of beamformed samples, a method and an apparatus compress each array of beamformed samples independently of the other arrays to form compressed beams. The compressed beams are transferred via a digital interface to a signal processor. At the signal processor, the compressed beams are decompressed to form decompressed beams. The signal processor further… Show more

In an ultrasound imaging system that applies a beamformer to received ultrasound signal samples to form one or more beams represented by arrays of beamformed samples, a method and an apparatus compress each array of beamformed samples independently of the other arrays to form compressed beams. The compressed beams are transferred via a digital interface to a signal processor. At the signal processor, the compressed beams are decompressed to form decompressed beams. The signal processor further processes the decompressed beams for diagnostic imaging, such as for B-mode and Doppler imaging, and scan conversion to prepare the resulting ultrasound image for display. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then decompressed prior to normal signal processing. For the downlink, the baseband processor compresses baseband signal samples and transfers the compressed signal samples to the RF unit. The RF unit decompresses the compressed samples prior to digital upconversion and digital to analog conversion to form an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including OBSAI or CPRI compliant systems. Show less

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens… Show more

A method and apparatus for compressing signal samples uses block floating point representations where the number of bits per mantissa is determined by the maximum magnitude sample in the group. The compressor defines groups of signal samples having a fixed number of samples per group. The maximum magnitude sample in the group determines an exponent value corresponding to the number of bits for representing the maximum sample value. The exponent values are encoded to form exponent tokens. Exponent differences between consecutive exponent values may be encoded individually or jointly. The samples in the group are mapped to corresponding mantissas, each mantissa having a number of bits based on the exponent value. Feedback control monitors the compressed bit rate and/or a quality metric. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses signal samples resulting from analog to digital conversion of an analog signal received via an antenna. The RF unit transfers the compressed signal samples over the serial data link to the base station processor where they are decompressed… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses signal samples resulting from analog to digital conversion of an analog signal received via an antenna. The RF unit transfers the compressed signal samples over the serial data link to the base station processor where they are decompressed prior to the normal signal processing operations. For the downlink, the base station processor compresses signal samples and transfers the compressed signal samples over the serial data link to the RF unit. The RF unit decompresses the compressed samples and converts the decompressed samples to an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems. Show less

A method and an apparatus for an ultrasound system provide compression of ultrasound signal samples after analog to digital conversion and before beamforming. The analog ultrasound signals received from an array of ultrasound transducer elements are digitally sampled by a plurality of analog to digital converters (ADCs) to produce a plurality of sequences of signal samples. Each sequence of signal samples is compressed to form a corresponding sequence of compressed samples. The resulting… Show more

A method and an apparatus for an ultrasound system provide compression of ultrasound signal samples after analog to digital conversion and before beamforming. The analog ultrasound signals received from an array of ultrasound transducer elements are digitally sampled by a plurality of analog to digital converters (ADCs) to produce a plurality of sequences of signal samples. Each sequence of signal samples is compressed to form a corresponding sequence of compressed samples. The resulting sequences of compressed samples are transferred via a digital interface to an ultrasound signal processor. At the ultrasound signal processor, the received sequences of compressed samples are decompressed. The typical processing operations, such as beamforming, downconversion and detection, are applied to decompressed samples. Show less

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and an interface between the stationary part and the rotatable part. A storage device using compression on the rotatable part can include one or more storage devices. For image reconstruction, compressed samples are retrieved from the storage device and transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received… Show more

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and an interface between the stationary part and the rotatable part. A storage device using compression on the rotatable part can include one or more storage devices. For image reconstruction, compressed samples are retrieved from the storage device and transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed samples and provides decompressed samples to the image reconstruction processor. Show less

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and a interface between the stationary part and the rotatable part. The rotatable part includes an x-ray source, a sensor array for detecting x-rays passing through the object to produce projection data samples, a compressor that compresses the projection data samples and a storage device that stores the compressed samples. The storage device on the rotatable part can… Show more

A computed tomography system has a stationary part, a rotatable part mounted for rotation around an object to be examined and a interface between the stationary part and the rotatable part. The rotatable part includes an x-ray source, a sensor array for detecting x-rays passing through the object to produce projection data samples, a compressor that compresses the projection data samples and a storage device that stores the compressed samples. The storage device on the rotatable part can include one or more solid state drives. For image reconstruction, the compressed samples are retrieved from the storage device, transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed samples and provides decompressed samples to the image reconstruction processor. Show less

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, and RF unit of the BTS compresses baseband signals resulting from analog to digital conversion of a received analog signal followed by digital downconversion. For the downlink, the baseband processor compressed baseband signal samples and transfers the compressed signal… Show more

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, and RF unit of the BTS compresses baseband signals resulting from analog to digital conversion of a received analog signal followed by digital downconversion. For the downlink, the baseband processor compressed baseband signal samples and transfers the compressed signal samples to the RF unit. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including CPRI or OBSAI compliant systems. Show less

A compression subsystem for a computed tomography system compresses projection data to for efficient data transfer and storage. The compression includes detecting edges in the projection data corresponding to the object being imaged to set boundaries for compression operations. The projection samples or the difference samples are compressed between the boundaries. The boundaries are encoded and included in the compressed data. The compressed samples are decompressed prior to image… Show more

A compression subsystem for a computed tomography system compresses projection data to for efficient data transfer and storage. The compression includes detecting edges in the projection data corresponding to the object being imaged to set boundaries for compression operations. The projection samples or the difference samples are compressed between the boundaries. The boundaries are encoded and included in the compressed data. The compressed samples are decompressed prior to image reconstruction processing. Decompression includes decoding the compressed samples and the boundary values. Show less

The invention describes various control and processing elements that implement a real-time compressor for time-interleaved A/D converters.

A compression subsystem for a computed tomography system compresses projection data to for efficient data transfer and storage. The compression includes applying an attenuation profile to an array of projection data samples. The attenuation profile is a function of sample coordinates and determines attenuation values applied to the samples. The attenuated samples are encoded and packed for data transfer. Alternatively, difference operators are applied to the attenuated samples and the… Show more

A compression subsystem for a computed tomography system compresses projection data to for efficient data transfer and storage. The compression includes applying an attenuation profile to an array of projection data samples. The attenuation profile is a function of sample coordinates and determines attenuation values applied to the samples. The attenuated samples are encoded and packed for data transfer. Alternatively, difference operators are applied to the attenuated samples and the differences are encoded. The average number of bits per compressed sample is monitored and the attenuation profiles can be modified to achieve a desired number of bits per compressed sample. The compressed samples are decompressed prior to image reconstruction processing. Decompression includes decoding the compressed samples and applying a gain profile to the decoded samples to restore the original dynamic range. This abstract does not limit the scope of the invention as described in the claims. Show less

A compression method and subsystem for a CT scanner compresses projection data from the data acquisition system. The projection data are classified into subsets of more significant samples and subsets of less significant samples. The subsets are compressed in accordance with compression control parameters so that the less significant samples are compressed to a greater degree than the more significant samples. The bit rate of the compressed projection data can be monitored and the compression… Show more

A compression method and subsystem for a CT scanner compresses projection data from the data acquisition system. The projection data are classified into subsets of more significant samples and subsets of less significant samples. The subsets are compressed in accordance with compression control parameters so that the less significant samples are compressed to a greater degree than the more significant samples. The bit rate of the compressed projection data can be monitored and the compression control parameters can be adjusted to provide a desired bit rate. The compressed data are decompressed in accordance with the compression control parameters for reconstruction of an image from the decompressed projection data. This abstract does not limit the scope of the invention as described in the claims. Show less

Compression of signal samples output from a parallel, time-interleaved analog to digital converter (TIADC) for a baseband signal, includes calculating first or higher order differences of consecutive signal samples followed by lossless or lossy encoding of the difference samples to produce compressed samples. Compression of a TIADC output signal with a nonzero center frequency, includes calculating sums or differences of pairs of signal samples separated by an appropriate number of sampling… Show more

Compression of signal samples output from a parallel, time-interleaved analog to digital converter (TIADC) for a baseband signal, includes calculating first or higher order differences of consecutive signal samples followed by lossless or lossy encoding of the difference samples to produce compressed samples. Compression of a TIADC output signal with a nonzero center frequency, includes calculating sums or differences of pairs of signal samples separated by an appropriate number of sampling intervals followed by lossless or lossy encoding. The sums or differences of the signal samples have lower magnitudes than the original samples, allowing more efficient compression. Lossy compression alternatives produce compressed data with a fixed bit rate or with a fixed quality in the decompressed samples. Alternatives for lossy compression include attenuating the analog signal before sampling by the TIADC, applying bit shifters or multipliers after sampling to reduce the magnitudes of the signal samples, and lossy encoding. Show less

Control of signal compression is coordinated by selectively modifying control parameters affecting the bit rate, sample rate, dynamic range and compression operations. Selected control parameters are modified according to a control function. The control function can include a ratio parameter that indicates the relative or proportional amounts of change to the control parameters. Alternatively, the control function can be represented in a lookup table with values for the selected control… Show more

Control of signal compression is coordinated by selectively modifying control parameters affecting the bit rate, sample rate, dynamic range and compression operations. Selected control parameters are modified according to a control function. The control function can include a ratio parameter that indicates the relative or proportional amounts of change to the control parameters. Alternatively, the control function can be represented in a lookup table with values for the selected control parameters related by the control function. Downsampling the input signal samples according to a sample rate control parameter is followed by upsampling to the original sample rate. Errors are calculated between the upsampled and original signal samples. Encoding of the downsampled signal samples and the error samples is performed in accordance with a compression control parameter. The sample rate control parameter and compression control parameter are determined based on the control function. Show less

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described for implementation as a single integrated circuit. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required… Show more

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described for implementation as a single integrated circuit. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required bit rate of the D/A converter's digital interface. D/A converters include a decompressor that decompresses the D/A converter's compressed digital input in real time, prior to conversion to an analog output signal. Show less

A compressor for waveforms having at least two waveform states separates the waveform samples into waveform state sample vectors for each waveform state. Waveform state encoders encode the waveform state sample vectors separately to provide compressed waveform data. The waveform state encoder selects waveform state pattern vector and associated codes to represent the waveform state sample vectors. The differences between samples of the waveform state sample vector and waveform state pattern… Show more

A compressor for waveforms having at least two waveform states separates the waveform samples into waveform state sample vectors for each waveform state. Waveform state encoders encode the waveform state sample vectors separately to provide compressed waveform data. The waveform state encoder selects waveform state pattern vector and associated codes to represent the waveform state sample vectors. The differences between samples of the waveform state sample vector and waveform state pattern vector are calculated and encoded. Encoding can be lossless or lossy. The waveform state pattern vectors and other parameters for compression are determined during a training period. The waveform state encoders detect features in the waveform state sample vectors and waveform state pattern vectors that are useful for common oscilloscope measurements. Typical waveform states include level states and edge states. Show less

In a frequency analysis system, such as a signal detection system or a spectrum analyzer, the frequency domain resolution is enhanced by compression and decompression of the signal samples. The limited capacity of the data storage and/or data transfer resources limit the number of samples that can be stored or transferred. A compressor forms a compressed signal prior to data transfer or storage. A decompressor decompresses the compressed signal prior to transformation to the frequency domain… Show more

In a frequency analysis system, such as a signal detection system or a spectrum analyzer, the frequency domain resolution is enhanced by compression and decompression of the signal samples. The limited capacity of the data storage and/or data transfer resources limit the number of samples that can be stored or transferred. A compressor forms a compressed signal prior to data transfer or storage. A decompressor decompresses the compressed signal prior to transformation to the frequency domain, by a fast Fourier transform or other frequency domain transform. The frequency domain resolution is enhanced because more decompressed samples are available for the frequency domain transform. The compressor and decompressor apply computationally efficient algorithms that can be implemented to operate in real time. Show less

Control of signal compression is coordinated by selectively modifying control parameters affecting the bit rate, sample rate, dynamic range and compression operations. Selected control parameters are modified according to a control function. The control function can include a ratio parameter that indicates the relative or proportional amounts of change to the control parameters. Alternatively, the control function can be represented in a lookup table with values for the selected control… Show more

Control of signal compression is coordinated by selectively modifying control parameters affecting the bit rate, sample rate, dynamic range and compression operations. Selected control parameters are modified according to a control function. The control function can include a ratio parameter that indicates the relative or proportional amounts of change to the control parameters. Alternatively, the control function can be represented in a lookup table with values for the selected control parameters related by the control function. The input signal samples can be resampled according to a sample rate control parameter. The dynamic range of signal samples can be selectively adjusted according to a dynamic range control parameter to form modified signal samples. The resampling and dynamic range adjustment can be applied in any order. The modified signal samples are encoded according to a compression control parameter to form compressed samples. The encoder can apply lossless or lossy encoding. Show less

An automated test system for a device under test (DUT) compresses the stimulus waveform before transferring it to a storage device or over a data transfer interface. The compressed stimulus waveform data are decompressed, and if required converted to analog form, then applied as a stimulus to the DUT. In response, the DUT produces a response waveform. The response waveform is compressed before transferring it to a storage device or over a data transfer interface. If the response waveform is… Show more

An automated test system for a device under test (DUT) compresses the stimulus waveform before transferring it to a storage device or over a data transfer interface. The compressed stimulus waveform data are decompressed, and if required converted to analog form, then applied as a stimulus to the DUT. In response, the DUT produces a response waveform. The response waveform is compressed before transferring it to a storage device or over a data transfer interface. If the response waveform is analog, it is converted to digital before compression. The compressed waveform is decompressed for further analysis or display by a host computer. Features of the response waveform can be calculated from the compressed or uncompressed waveform data. Several configurations that include compression and decompression of stimulus and/or response waveforms in test systems are described. Show less

A compressor for waveforms having at least two waveform states separates the waveform samples into waveform state sample vectors for each waveform state. Waveform state encoders encode the waveform state sample vectors separately to provide compressed waveform data. The waveform state encoder selects waveform state pattern vector and associated codes to represent the waveform state sample vectors. The differences between samples of the waveform state sample vector and waveform state pattern… Show more

A compressor for waveforms having at least two waveform states separates the waveform samples into waveform state sample vectors for each waveform state. Waveform state encoders encode the waveform state sample vectors separately to provide compressed waveform data. The waveform state encoder selects waveform state pattern vector and associated codes to represent the waveform state sample vectors. The differences between samples of the waveform state sample vector and waveform state pattern vector are calculated and encoded. Encoding can be lossless or lossy. The waveform state pattern vectors and other parameters for compression are determined during a training period. The waveform state encoders detect features in the waveform state sample vectors and waveform state pattern vectors that are useful for common oscilloscope measurements. Typical waveform states include level states and edge states. Show less

Multiple copies of a software or operating parameter change are broadcast using a wireless signal to a mobile electronic device. Broadcasting multiple copies increases the probability that the mobile electronic device will receive the change without error. The number of copies broadcast is a function of the expected probability that the device will receive one copy without error and a desired probability that the device will receive the change without error.

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required bit rate of the D/A converter's digital interface… Show more

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required bit rate of the D/A converter's digital interface. D/A converters include a decompressor that decompresses the D/A converter's compressed digital input in real time, prior to conversion to an analog output signal. Show less

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required bit rate of the D/A converter's digital interface… Show more

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. Improved A/D converters compressing a sampled version of an A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, improved D/A converters decrease the required bit rate of the D/A converter's digital interface. D/A converters include a decompressor that decompresses the D/A converter's compressed digital input in real time, prior to conversion to an analog output signal. Show less

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. The present invention improves A/D converters by compressing the sampled version of the A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, the present invention improves D/A converters by decreasing the… Show more

An enhancement that reduces the digital interface rate of analog-to-digital (A/D) and digital-to-analog (D/A) converters through the use of compression and decompression is described. The present invention improves A/D converters by compressing the sampled version of the A/D converter's analog input signal in real time, thereby significantly decreasing the required bit rate of the A/D converter's digital interface. Similarly, the present invention improves D/A converters by decreasing the required bit rate of the D/A converter's digital interface. D/A converters enhanced by the present invention include a decompressor that decompresses the D/A converter's compressed digital input in real time, prior to conversion to an analog output signal. The present invention's simplicity and its ability to be implemented using multiple compression and decompression elements allow its use in A/D and D/A converters with arbitrarily high sampling rates. By selecting a desired compression ratio during lossy compression, users of the present invention can precisely control the bit rate of the A/D and D/A converter's digital interface. Users of the present invention can dynamically choose the desired balance between the quality and the bit rate of A/D and D/A converters by adjusting various compression and decompression control parameters. Show less

An efficient method for compressing sampled analog signals in real time, without loss, or at a user-specified rate or distortion level, is described. The present invention is particularly effective for compressing and decompressing high-speed, bandlimited analog signals that are not appropriately or effectively compressed by prior art speech, audio, image, and video compression algorithms due to various limitations of such prior art compression solutions. The present invention's preprocessor… Show more

An efficient method for compressing sampled analog signals in real time, without loss, or at a user-specified rate or distortion level, is described. The present invention is particularly effective for compressing and decompressing high-speed, bandlimited analog signals that are not appropriately or effectively compressed by prior art speech, audio, image, and video compression algorithms due to various limitations of such prior art compression solutions. The present invention's preprocessor apparatus measures one or more signal parameters and, under program control, appropriately modifies the preprocessor input signal to create one or more preprocessor output signals that are more effectively compressed by a follow-on compressor. In many instances, the follow-on compressor operates most effectively when its input signal is at baseband. The compressor creates a stream of compressed data tokens and compression control parameters that represent the original sampled input signal using fewer bits. The decompression subsystem uses a decompressor to decompress the stream of compressed data tokens and compression control parameters. After decompression, the decompressor output signal is processed by a post-processor, which reverses the operations of the preprocessor during compression, generating a postprocessed signal that exactly matches (during lossless compression) or approximates (during lossy compression) the original sampled input signal. Parallel processing implementations of both the compression and decompression subsystems are described that can operate at higher sampling rates when compared to the sampling rates of a single compression or decompression subsystem. In addition to providing the benefits of real-time compression and decompression to a new, general class of sampled data users who previously could not obtain benefits from compression, the present invention also enhances the performance of test and measurement equipment, busses, and networks. Show less

Multiple copies of a software or operating parameter change are broadcast using a wireless signal to a mobile electronic device. Broadcasting multiple copies increases the probability that the device will receive the change without error.

Broadcast programs, e.g., for an audio information program, are divided into one or more segments and are broadcast to a receiver in packet format. The receiver captures the transmitted packets and reassembles the segments and the program for storage and subsequent output to the user. Segment quality of service is evaluated prior to output by ensuring that a minimum percent of packets per segment are usable, and by ensuring that no more than a maximum number of consecutive packets in the… Show more

Broadcast programs, e.g., for an audio information program, are divided into one or more segments and are broadcast to a receiver in packet format. The receiver captures the transmitted packets and reassembles the segments and the program for storage and subsequent output to the user. Segment quality of service is evaluated prior to output by ensuring that a minimum percent of packets per segment are usable, and by ensuring that no more than a maximum number of consecutive packets in the segment are unusable. Program quality of service is evaluated by ensuring that a minimum percent of segments per program are usable, and by determining if the first and/or last segment is usable. Different quality of service parameters are specified for particular programs. New quality of service parameters for particular programs are transmitted to the receiver. Show less

In a local storage and playback broadcast system, multiple copies of one or more processing parameters used in individual receivers for the local storage and playback are broadcast. In some embodiments each processing parameter is associated with each packet in the program so that a copy of each parameter is broadcast with each packet. In some embodiments the program is divided into segments, each segment having a header, and a copy of the parameter is broadcast in each segment header.

The quantity of unused channels in a cellular wireless communications system is identified. From program content that is stored in a database, an amount of program content is accessed based on the identified quantity of unused channels. The accessed program content is formatted for broadcast on at least a portion of the unused channels, and the formatted content is then transferred to the cellular wireless communications system for broadcast to mobile receivers. In some embodiments a content… Show more

The quantity of unused channels in a cellular wireless communications system is identified. From program content that is stored in a database, an amount of program content is accessed based on the identified quantity of unused channels. The accessed program content is formatted for broadcast on at least a portion of the unused channels, and the formatted content is then transferred to the cellular wireless communications system for broadcast to mobile receivers. In some embodiments a content transmission schedule is broadcast on one of the unused channels. Show less

Audio and/or video content is remotely stored. A portion of the remotely stored content is transferred to and stored in a mobile on-demand audio and/or video content output device. In addition, a link is transferred to and stored in the mobile output device. The link is associated with the content portion stored in the output device and points to another portion of the remotely stored content that is related to the content portion locally stored on the mobile device. In response to a user… Show more

Audio and/or video content is remotely stored. A portion of the remotely stored content is transferred to and stored in a mobile on-demand audio and/or video content output device. In addition, a link is transferred to and stored in the mobile output device. The link is associated with the content portion stored in the output device and points to another portion of the remotely stored content that is related to the content portion locally stored on the mobile device. In response to a user command entered on the mobile device, the related portion of the remotely stored content is accessed using a two-way wireless communications system and is transferred from the database to the mobile device for output. Show less

An efficient method for compressing audio and other sampled data signals without loss, or with a controlled amount of loss, is described. The compression apparatus contains a subset selector, an approximator, an adder, two derivative encoders, a header encoder, and a compressed block formatter. The decompression apparatus contains a compressed block parser, a header decoder, two integration decoders, an approximator, and an adder. The compressor first divides each block of input samples into a… Show more

An efficient method for compressing audio and other sampled data signals without loss, or with a controlled amount of loss, is described. The compression apparatus contains a subset selector, an approximator, an adder, two derivative encoders, a header encoder, and a compressed block formatter. The decompression apparatus contains a compressed block parser, a header decoder, two integration decoders, an approximator, and an adder. The compressor first divides each block of input samples into a first subset and a second subset. The approximator uses the first subset samples to approximate the second subset samples. An error signal is created by subtracting the approximated second subset samples from the actual second subset samples. The first subset samples and error signal are separately encoded by the derivative encoders, which select the signal's derivative that requires the least amount of storage for a block floating point representation. A compressed block formatter combines the compression control parameters, encoded subset array, and encoded error array into a compressed block. The decompression apparatus first parses the compressed block into a header, an encoded first subset array, and an encoded error array. The header decoder recovers the compression control parameters from the header. Using the compression control parameters, the integration decoders reconstruct the first subset and error arrays from their block floating point representations. The approximator uses the first subset samples to approximate the original second subset samples. The adder combines the subset samples, the error samples, and the approximated second subset samples to identically re-create the original, uncompressed signal. An indexing method is described which allows random access to specific uncompressed samples within the stream of compressed blocks. Show less

Allowable claims: Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to… Show more

Allowable claims: Configurable compression and decompression of waveform data in a multi-core processing environment improves the efficiency of data transfer between cores and conserves data storage resources. In waveform data processing systems, input, intermediate, and output waveform data are often exchanged between cores and between cores and off-chip memory. At each core, a single configurable compressor and a single configurable decompressor can be configured to compress and to decompress integer or floating-point waveform data. At the memory controller, a configurable compressor compresses integer or floating-point waveform data for transfer to off-chip memory in compressed packets and a configurable decompressor decompresses compressed packets received from the off-chip memory. Compression reduces the memory or storage required to retain waveform data in a semiconductor or magnetic memory. Compression reduces both the latency and the bandwidth required to exchange waveform data. Show less

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are… Show more

In a distributed antenna system (DAS) and a local area network (LAN), a common communication infrastructure distributes data from radio-based and Internet-based sources. A radio equipment (RE) of the DAS interfaces to a LAN segment. For the downlink, a gateway maps radio signal data from a radio equipment controller (REC) and data packets from a switch to mixed-data frames using a radio data interface protocol for transmission in the DAS. At the RE, the signal data and data packets are retrieved from the mixed-data frames and provided to the air interface and LAN segment, respectively. For the uplink from the RE, the radio signal data from the air interface and the data packets from the LAN segment are mapped to mixed-data frames and transmitted to the gateway. The gateway retrieves the signal samples and data packets from the mixed-data frames for transfer to the REC and switch, respectively. Show less

An enhancement that improves the performance of test and measurement equipment such as digital oscilloscopes and arbitrary waveform generators through the use of compression and decompression is described. The present invention is particularly effective for compressing and decompressing high-speed, bandlimited analog signals that are not appropriately or cannot effectively be compressed by prior art speech, audio, image, and video compression algorithms due to various limitations of such prior… Show more

An enhancement that improves the performance of test and measurement equipment such as digital oscilloscopes and arbitrary waveform generators through the use of compression and decompression is described. The present invention is particularly effective for compressing and decompressing high-speed, bandlimited analog signals that are not appropriately or cannot effectively be compressed by prior art speech, audio, image, and video compression algorithms due to various limitations of such prior art compression solutions. The present invention improves digital oscilloscopes by compressing the sampled version of an analog waveform under observation in real time, allowing a significantly longer duration of the waveform to be stored in the oscilloscope's capture memory, when compared with the duration of the same signal's uncompressed waveform stored in the same memory. Similarly, the present invention improves arbitrary waveform generators by storing a compressed version of a desired arbitrary waveform, instead of the uncompressed version of the arbitrary waveform, in the signal generator's waveform memory. During signal generation, the compressed waveform is decompressed in real time. The uncompressed waveform drives a D/A converter that generates the desired analog waveform. The present invention's simplicity, and its ability to be implemented using parallel compression and decompression elements, allows its use at the high sampling rates of test and measurement instruments. Using the present invention, storage elements in test and measurement equipment can hold significantly longer waveforms in a fixed amount of memory. Users of the present invention can also determine the proper balance between the fidelity and the duration of the decompressed waveform by adjusting various compression and decompression control parameters. Show less

Compression of signal samples output from a parallel, time-interleaved analog to digital converter (TIADC) for a baseband signal, includes calculating first or higher order differences of consecutive signal samples followed by lossless or lossy encoding of the difference samples to produce compressed samples. Compression of a TIADC output signal with a nonzero center frequency, includes calculating sums or differences of pairs of signal samples separated by an appropriate number of sampling… Show more

Compression of signal samples output from a parallel, time-interleaved analog to digital converter (TIADC) for a baseband signal, includes calculating first or higher order differences of consecutive signal samples followed by lossless or lossy encoding of the difference samples to produce compressed samples. Compression of a TIADC output signal with a nonzero center frequency, includes calculating sums or differences of pairs of signal samples separated by an appropriate number of sampling intervals followed by lossless or lossy encoding. The sums or differences of the signal samples have lower magnitudes than the original samples, allowing more efficient compression. Lossy compression alternatives produce compressed data with a fixed bit rate or with a fixed quality in the decompressed samples. Alternatives for lossy compression include attenuating the analog signal before sampling by the TIADC, applying bit shifters or multipliers after sampling to reduce the magnitudes of the signal samples, and lossy encoding. Show less