Low-SNR asymptote of CRB on SNR estimates for BPSK in Nakagami- <i>m</i> fading channels with diversity combining

Abstract

A simple closed-form expression is derived for the low signal-to-noise ratio (SNR) asymptote of the Cramér-Rao bound (CRB) for estimating the SNR of binary phase shift keying modulated signals received over Nakagami-m fading channels with L branch equal gain combining diversity.