Method and apparatus for low power simultaneous frequency, automatic gain control and timing acquisition in radio receivers

Abstract

A method and apparatus are provided for low power simultaneous frequency, automatic gain control and timing acquisition in a low power radio receiver. A baseband signal received is split into a limited signal having limited data and a non-limited signal. The limited signal is fed through a limited phase-shift keying (PSK) correlation path in which a PSK correlator operating on the limited signal simultaneously determines coarse frequency estimations, timing estimations, and packet synchronization detection. The non-limited signal is fed through an automatic gain control path where automatic gain control is performed on the non-limited signal simultaneously with the coarse frequency and timing estimations and packet synchronization detection performed by the PSK correlator. By operating the PSK correlator on limited data from the received baseband signal and through a separate path from the automatic gain control, substantial power savings are achieved without degrading performance since the preamble time is significantly reduced.