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Same thing in opposite direction. A by antenna received signal is transferred ta an impedance matched receiver and almost all power is is absorbed by receiver. Non ideal losses in antenna and cable can not be avoided but in general is all power absorbed by receiver in a matched system.
If a less...
A possible fourth parameter to be taken in account and which can interfere with other PA optimum loads: max stability impedance.
If not doing conjugate match can things go wrong if effect of feed transmission line impedance is taken in account, if transmission line have a decent length...
Seen from fare field is phasecenter an electric reference point for each frequency.
That is what I use as reference distance and for assuming received relative phase position.
Phasercenter Is a defined function in CST.
Phase center description: https://en.wikipedia.org/wiki/Phase_center
Horn...
If antenna have been fabricated, why? It is in that case very poor fabricated antenna.
Impedance curve shows poor matching for all frequencies and measured values from above does not even seem likely that they are correct measured or else is it an unusual antenna.
I did use your values from...
Calculate matching result is possible but it is harder to design wide band optimized topologies and values in ADS for lossy components.
Real resistance ratio is about 150 times from 0.3 to 50 Ohm. It is a bit too much to match in a single step. It can easily cost a lot of losses.
Real...
It is a huge difference matching 2-2.5 GHz relative 300-900 MHz, using passive reactive components.
2.5 GHz is 25% above 2 GHz and 900 MHz is 300% above 300 MHz. It is a factor more then 10x in tuning range. Add that actual curve is way off from matching impedance goal.
It is also a huge...
Most of us, even if we not know theory behind do we have experience that a dipole antenna shorter then lambda/2 is less efficient. The shorter, the less efficient.
That is true for all short dipoles and is so well known that I doubt someone can be serious saying that this is a confused kind of...
>? Is the sky limit, or is just your guess? Give me numbers please.
Antenna as short dipole/monopole is pretty linear as long as total length is assumed to be less then lambda 1/2.
Numbers, no, but needed formulas so that you can do the calculation by yourself can be found by following by me...
Yes it is rather natural for an such antenna to be more effective at higher frequencies. It can almost be said to be a must as we are comparing simple antenna lengths and ground lengths shorter then 1/4 lambda for 868 MHz while at 2.4 GHz is 40 mm PCB an acceptable ground plane length as...
Sorry but this earpiece was a development project many years ago and it have been reconfigured several times and I did no real initial measurement.
Anyhow is it relative easy to retune it to 865 MHz using just two components and it was a fair question, I wonder too what it could been from...
I have evaluated box size and other parameters for a few years now and compared result with well calibrated multi-reverberation/anechoic chambers, literally world around, with aid of helpful RF-labs.
Result is most accurate when size of box is limited relative wave-length but more important is...
This is a bit AD for my self but think it is relevant. I develop antennas, mostly embedded cellphone antennas, but do also develop software for controlling instruments used in combination of RF measurement ranges, typical turntables calltesters and VNA.
When I measure a wide band antenna...
Above proposed budget RF meters will do the job. Both can transmit over a wide frequency range. A maybe important difference is that WinNWT4 have a non frequency selective power meter as detector.
If however actual need is just to transmit a WiFi-signal and be able to detect a level can any...
As a simple example, a near ideal 0.5 lambda dipole, center freq. 900MHz, impedance 84+j30 Ohm, is tuned to cover 860-930MHz with lowest possible VSWR.
Brown curve in Smith chart shows measured antenna impedance before tuning and yellow curve after tuning network have been applied.
All are...
You can find a lot of diode detectors by searching.
Here is one example: http://www.dcon.com.br/jd.comment/articles/TestGear2_4ghz.htm
VSWR meters: **broken link removed**
Buy or copy: http://www.ebay.com/itm/RF-bridge-0-5-3000-MHz-VNA-Return-Loss-VSWR-SWR-reflection-bridge-antenna/332052527822...
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