Accurate estimation of digital communication system metrics - SNR, EVM and ρ in a nonlinear amplifier environment

A nonlinear spectral analysis technique that enables digital communication system metrics; SNR, EVM and the waveform quality factor (ρ) to be related to in-band distortion spectrum is presented. System metrics are estimated from the measured output power and in-band distortion power. The estimated metrics are verified by direct measurements of each metric using a vector signal analyzer (VSA) performed on a forward-link IS-95 signal. Estimated system metrics are in excellent agreement with measured values.