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Inconsistent receiver power between 2 transmissions of the same signal

I am transmitting an OFDM symbol using 2 Plutos and I am using iio in C to process the signals. The devices are in the exact same position and in a relatively static environment. I have linked images of an example of the same signal being transmitted with the variability in the in-phase component being shown. I am not really sure why it is varying so much. I have the hardware gain control mode set to "manual" and set a specific hardware gain that is fixed.


To further show the issue. I set up another receiver, so there are 2 receivers running the same code. I transmit from a 3rd device once and receive at the same time on both the receivers. The same signal received on both devices is shown in the image below. The syrchronization is off between the receivers, but you can see that the voltage is like 10 dB higher for one compared to the other.

What to make clear that the images are the in-phase component of the transmitted signal
[edited by: rabubake at 7:11 PM (GMT -5) on 14 Nov 2023]