Hi David,
As per my understanding, you want to configure the ADALM-PLUTO device to reduce the Bit Error Rate (BER) in your model.
The value of BER (in your case 0.5) can be the result of multiple factors with frequency offset being one of the crucial factors. Frequency offset refers to the difference between the intended frequency and the actual frequency at which the device operates. This can lead to the reduction of Signal-to-Noise Ratio (SNR) thereby increasing the BER.
To avoid this, the transmitter and receiver (ADALM-PLUTO devices) are to be properly configured to have minimum frequency offset. Kindly refer to the following documentation on how to determine the relative frequency offset between two ADALM-PLUTO devices:
You can then calibrate the devices by adjusting the center frequency with respect to the frequency offset value.
Hope this helps.