Abstract: An accurate total error rate performance can be measured using a computed error vector magnitude (EVM) per stream. Using this EVM, the receiver or the transmitter can advantageously generate an optimized modulation and coding scheme (MCS) that corresponds to a specific number of streams, modulation and coding rate for the transmitter. For example, the receiver can compute an SNR from the EVM and then use an SNR vs. MCS table to determine the optimized MCS. In contrast, the transmitter can receive an EVM-to-RSSI mapping and an EVM-to-MCS mapping from the receiver. These mappings and an EVM can facilitate selecting the optimized MCS.