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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High Insertion Loss on 4 Layer 5.8 GHz Board
I've built a board to serve as the front end of a 5.8 GHz Wi-Fi radio. The boards were built using OSH Park's 4-layer service, which uses ISOLA FR408-HR. It seems like these boards should be ...
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If ESR for a capacitor is not given, can you use f, C, and Q to calculate it?
To calculate ESR when it is not given, can you use the \$Q\$ value as follows?
According to Wikipedia, dissipation factor relates \$Q\$, \$\text{ESR}\$, and \$\tan(\delta)\$ as follows:
$$
\frac{1}{Q} ...
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Can we use telescopic antenna for RF receivers?
Can we use TE antenna for receiver? Because I have seen that TE antenna is used in transmitters and for receivers spring coil antenna is used.
The reason that I have asked this question is I have seen ...
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Injecting bits to a parallel communication bus possible?
Antennas can recieve data (bits) because RF signals induce an analog signal into it in a serial format, essentially a voltage that varies over time. My question is can we have an antenna that can ...
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Visualizing 2 Layer PCB Return Currents
Hobbyist moving a manhattan-style prototype of an analog FM radio to a PCB for ease of assembly and access to SMT parts. I have attempted a 2 layer FR4 board with a 1.6mm thickness, as I feel that ...
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Why do direct conversion receivers amplify only after mixing?
The vast majority of the simple direct conversion receivers I've seen amplify only after mixing. The RF is filtered before mixing, but not amplified at all. For example (from Solid State Design for ...
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Unable to replicate Twisted IFA antenna S-parameter curve using ANSYS HFSS 15
I am attempting to replicate the S-parameter curve for an antenna design as described in the paper "Antenna Design and Analysis" with DOI: 10.1109/LAWP.2009.2015345 using ANSYS HFSS 15.
Here ...
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What is the purpose of this table on RF remote controls?
On most of the RF remote controls we can see this table. Can you explain what it means?
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What is the optimal way to place a BNC connection point on a printed circuit board?
I am working on my first RF project and I have two signals coming onto my board through a BNC connection. I have selected this BNC but their data sheet is not very informative.
https://www.digikey.com/...
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ideal N-port Touchstone spec
Want to specify ideal i.e. frequency independent S-parameter N-port components in Touchstone file (v1 or v2), for import into circuit simulator.
The official specs don't mention how many frequency ...
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Where should I take the measurement from to find the correct attenuation level of a resistive pi attenuator?
I am currently designing a resistive attenuator for an RF project I'm working on. I wanted to have several resistance combinations to obtain various attenuation levels (1-8 dBs). When I calculate the ...
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BJT Gilbert cell with emitter-degeneration
I am trying to design a Gilbert cell mixer. I am stuck on one requirement.
Background: The RF differential voltage swing should above 900mVpp (currently RF=991.2mVpp.) This swing must remain the same....
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Modeling a short 10mm wire for RF
This is related to another question of mine looking for parasitics which need to be added to prevent oscillations in simulations .
How should I model a short 10nH wire (say AWG 20 with 0.8 mm diameter ...
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Can this oscillator possibly work?
I am trying to build a crude RF oscillator. My first attempt, though it simulated fine, disappointingly did not oscillate when soldered together. So, to debug this, I reduced the simulation example ...
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How can I simulate an RF signal as received by an antenna in LTspice?
How can I simulate an RF signal as received by an antenna in LTspice?
I am designing a simple HF RF receiver and want to test it via LTspice. Can I simulate an RF signal as:
A pure voltage source, ...
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