This seems like a wild work around to retrofit a non-MIMO system into the modern era with beamforming chips a-plenty. While it's interesting to consider using a

This seems like a wild work around to retrofit a non-MIMO system into the modern era with beamforming chips a-plenty. While it's interesting to consider using an AI to detect and steer the beam using the harmonics of the received signal, it's important to bear in mind these will be about 20 dB down from the fundamental received frequency. It would be far more reliable to employ a phased array transceiver which can do multiple concurrent beamforming operations. This would allow the use of the antenna for multiple connections on the fundamental frequency. If it's truly for a single channel/single user, it would be simpler to simply time-multiplex a search for reflections by random sampling, or perhaps even gradient descent.