Spectral efficiency optimized MIMO transmission using AMC and power assignment based on SNR ordering

A new transmission scheme is designed to maximize average spectral efficiency in a MIMO link considering instantaneous bit error rate (BER) and total power constraints. Discrete link adaptation using adaptive modulation and coding (AMC) is utilized to combat multipath fading which is implementable in practical systems. ZF receiver is employed by which MIMO channel becomes equivalent to several parallel non interfering links. Instead of the mentioned actual links, virtual links are considered which are ordered based on their SNRs. Optimized power levels are assigned based on SNR ordering provisioning total power constraint. Numerical evaluations show a noticeable performance improvement by the proposed scheme compared to the scheme in which power is uniformly divided among actual links.