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I think is not so easy to check the impedances of the bias path especially at the higher frequencies. This is mainly due to the difficulty to accurately calibrate the launchers.
The circuit can oscillate (self-oscillation) with no RF at the input.
You said that in the simulation the circuit...
It seems your circuit is not stable and the transistor starts to oscillate. Possibly your idea to eliminates the need of bypass capacitor is not working. However in order to help you should attach the schematic diagram.
In the video you posted I can see an amplitde modulate sinewave with a superimposed DC (from the oscilloscope measurement). The DMM is set on "DC" so it only measures the DC components of the signal that is constant. You coud set the DMM on "AC" to see the RMS (if it is a true RMS voltmeter) but...
The summer is composed by 10 resistor of values [R, 2R, 3R...2^(N-1)R] connected between MSB, MSB-1, MSB-1...LSB] bit and inverting pin of the opamp. Let's call the feedback resitor Rf.
When only the LSB bit is connected to Vi and the others left open, the output voltage will be...
Here is my analysis. It should be valid as far as the op-amp can be considered (almost) ideal. If the frequency increases and the input capacitance (between inverting and non-inverting pin) starts to play a role this quite simple math loose validity. How much can be high the frequency depends...
Probably there is a LDO (low drop out voltage regulator) insider the antenna, then the lna is always supplied with the same voltage, thus the current consumption doesn't change on the whole input voltage range
No, the (low level) RF signal will not affect the DC measurement. However the insertion of the measurement system, if not properly RF decoupled will affect the RF performances of the antenna.
If you want just measure once the current consumption you can use the multimeter that has to be removed...
If you need hig accuracy you have definitely to go with a simulator.
However I'm still no sure about the actual geometry of the whole system, I mean all the wires and their position in space as well as the measurement point that as far as I've correctly understood it's place from 5 to 15 cm...
I'll try to answer your questions:
2. you are rigth, in a three phase system the currents Ia, Ib and Ic are shifted by 120deg each other (supposing a well balanced resistive load). I forgot a "2" term i.e. instead of pi/3 consider 2*pi/3 and instead of 2*pi/3 consider 4*pi/3
3. Simply...
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