  This paper proposes a genetic algorithm assisted hybrid signal to leakage
plus noise ratio (SLNR) beamforming design for wireless fronthaul scenario. The
digital precoder of the proposed hybrid SLNR beamforming is expressed in
closed-form. Highly limited phase resolution (one-bit resolution) is assumed at
the phase shifters at the analog precoder. The analog precoders maximizing the
approximated sum rate are presented. Genetic algorithms are used to search for
optimal solutions of one-bit analog precoders. In contrast to common
assumptions on perfect knowledge of the true channel matrix at the transmitter,
the proposed method relies only on the distorted channel matrix after the
analog precoder. Performance of the proposed hybrid SLNR beamforming with
limited phase resolution at the analog precoder can achieve performance close
to digital beamforming in single cell wireless fronthaul scenarios. It is also
shown that hybrid beamforming can result in undesired beams causing intercell
interference in multicell wireless fronthaul scenarios.
