Fix(ANN.py): Real signals, efficiency
Fix(ANN.py): Real signals, efficiency

1. Major fix: use real signals to compute CSM, then average over
frequencies and get the absolute value.
--> Makes the net a completely real net.

2. Use RF data or real IQ data.

3. Efficiency: compute lower triangle of CSM and mirror it.

TODO:
1. How to deal with distances?

waynezv/ANN,waynezv/ANN