Questions tagged [rf]
Short for Radio Frequency, i.e. frequencies at which radiation (intentional or not) plays a role. Typically associated with wireless communications, but also relevant for high-speed PCB design.
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Advice needed: Low-power mobile uplink detection system design (RF beginner) [closed]
For a university project, I am trying to design a system capable of locating uplink signals emitted by mobile phones.
The Constraints: I need to scan different frequency bands corresponding to various ...
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Can a magnetic loop antenna be used to communicate through a perfect metal container?
I understand that in the near field of a loop antenna the magnetic field dominates, before it has formed a radiative propagating EM wave. Based on this, and the fact that magnetic fields can penetrate ...
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Looking for Feedback on My 4-Layer PCB Design With Chip Antenna (Screenshots Attached)
I'm working on a 4-layer PCB that uses this 2.4 GHz chip antenna, and I'd appreciate some expert opinions or comments on the layout. This board will be used for Wi-Fi/BLE, and I want to ensure good RF ...
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Advice on S Band RF GaN transistor with MWO libraries
I'm designing a microwave class F power amplifier, and I'd need a transistor in the 2.7-2.9 GHz range with at least 10 dB gain (16 dB would be ideal, but feel free to advice anything above that ...
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Best approach to sweep 410-525 MHz? PLL/VCO vs ramped timer vs sweep-IC? [closed]
I want to design a frequency synthesizer with a frequency sweep covering 410-525 MHz. I’m considering several approaches but want advice on real-world practicality:
Simple ramp voltage → timer IC → ??...
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SMA Edge Mount Connector Placement
I would like to measure the input/output impedance of some circuits from 1 MHz-200 MHz using a nanoVNA.
PCB stackup is Sig/GND/GND/+5V, Sig does not have a ground pour on the same layer.
Trace width ...
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Modeling RF Impedance Matching PCB Geometry
I am designing RF amplifiers, and I often use LDMOS transistors with unmatched inputs and outputs. My goal is to learn how to model and simulate PCB impedance-matching geometry on a computer before ...
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How to layout a transmission line for impedance matching when using a chip antenna
I will be designing a PCB layout for a LoRa module very similar to this one, but with a chip antenna instead of a U.FL connector.
It seems that this one has a pi matching network for matching the ...
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433.92 TX 12V Prototype Review
I have been using 433 RF TX ICs that work well at 3.3V however I wanted to try and test out a 12v 433 TX circuit. Only digital AM ASK/OOK used.
I'm running my circuit on a LiPo battery so I though the ...
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Choice of PCB Material for HF RF circuit
I am currently designing an FM Radio (88MHz - 108MHz) and have gotten to a point in the design where I am beginning the layout plan / make some general design decisions about manufacturing.
I plan to ...
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Purpose and selection of inductor for RF power amplifier that has a VCC pin (MAX2616)
I am currently building an RF amplifier PCB for around ~2.4 GHz using the MAX2616, which is a broadband RF amplifier for 40 MHz to 4000 MHz.
Looking at the datasheet, I am confused about the purpose ...
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Very low RF-DC conversion efficiency in ADS (SMS7630 & HSMS-282E)
Simulating RF rectifier in ADS (2.45 GHz, 5 dBm). Using HSMS-282E gives 11% PCE, SMS7630 gives 20% PCE. Matching is correct (good S11). Using SPICE models from datasheets. Load = 2 kΩ. Using HB with ...
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Bluetooth Antenna Characteristics
When looking at an antenna datasheet, there is a polar plot (below image) that shows the antenna's characteristics in different planes.
I would like to know what this plot represents. Is it EIRP, ...
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Designing first RF circuit and wondering how to pick passive components on the RX and TX line
This is the first time I'm doing stuff with RF and I am using the STM32WL30KBV6. I plan on using it for LORAWAN communication but I'm having trouble figuring out what passive values I should be using ...
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How are the shunt coupling capacitors chosen in this double-tuned HF bandpass filter, and how do they affect the resonance and bandwidth?
I am studying a tunable double-tuned band-pass filter used as an HF preselector. A reference implementation is here: http://www.qrp.gr/hf_allband_filter.htm
The topology is:
Two LC resonators (left ...
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