Questions tagged [antenna]
Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g. TV or radio) waves. -Wikipedia
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Does the inside surface of pipe material conduct significant RF current in small TX loop antennas?
Small transmitting aka "magnetic" loop antennas are often constructed out of copper or aluminum pipe material. Antennas don't need to be solid due to the skin effect.
Does the skin effect ...
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AN6305 “resistor bridge” connection—are both pads GND-to-GND (parallel to ground) for antenna tuning?
I’m following the ST application note AN6305, which recommends adding a “resistor bridge” [Page No-17, Fig-21] (a tuning component network) to allow fine antenna matching. The document shows this ...
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How can an antenna that is only 1 m long receive AM radio with a wavelength of 281 meters? [closed]
I was looking at the US Frequency Allocations Chart (2003) and it stated that AM radio falls in the range of 535 to 1605 kHz. I converted this to wavenlength and thats at least 281 meters. From my ...
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Ground Plane as radial for monopole on PCB
How do the attributes / characteristics of a PCB ground plane affect the performance of a single-pole wire antenna? I'm developing a 4-layer board (signal-ground-power-signal, both signal layers with ...
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How to determine passive component values for NEO M8U active antenna?
I need to integrate the NEO-M8U GPS module into a PCB design. I want to use the active antenna supplied with the VCC_RF voltage pin. So I followed the scheme mentioned on the 2.4.2 section of hardware ...
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UHF antenna matching RF ID
I’m facing an issue with impedance matching in this circuit. For each unit in production, I need to retune the matching network because even small variations in PCB trace impedance shift the antenna’s ...
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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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How properly bias pin diode on a RF resonator
Biasing of RF resonator with pin diode
Here a paper my question origins from
“Programmable Metasurface Based on Substrate-Integrated Waveguide for Compact Dynamic-Pattern Antenna”, from Shangyang Li ...
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Why aren't the antenna terminals on a WiFi card terminated at their characteristic impedeance?
I have noticed on several occasions that some internal WiFi cards and some motherboards with WiFi provide open, unterminated, antenna connections.
I am starting with the following assumptions:
A WiFi ...
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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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Getting a radiation pattern plot from a phased array digital beamformer
I constructed an antenna device (2RX 1TX) from this Jon Kraft video for an ongoing project in an anechoic chamber. In all honesty, my knowledge in this area is quite limited and I'm a getting a bit ...
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Unexpected Noise Floor Behavior on S2LP Receiver – Need Help Understanding
I’m currently developing a handheld device using the S2LP as an RF transceiver, and I’ve run into something I can’t quite explain about the noise floor during receive mode.
Here’s the noise floor the ...
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Where should I connect my VNA for impedance matching on a wireless module?
I’m new to RF design and need some guidance. My board has a wireless module where the ANT output goes through a matching network and then to a U.FL connector, which connects to the antenna. This chip ...
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How Does a Faraday Cage Not Radiate?
I am confused at how a Faraday cage can shield enclosed electronics without becoming an antenna.
Situation 'A': Consider a particle inside an ungrounded metallic Faraday cage whose charge oscillates ...
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NFC vs RFID: want to clarify the basic working principle
I am getting confused and overwhelmed by all the information about communication protocols etc. when I want to just clarify the basic physics.
NFC: From what I can tell it's just basic inductive ...
