Patent ID: 8630374

Claim:
A packet detection and coarse symbol timing recovery system for preamble signal modulated with rotated differential M-ary phase shift keying (PSK) modulation, comprising: a serial-to-parallel unit, responsive to a received signal, to branch the received signal into plural parallel received signals each operating at a same symbol rate and one of plural different sampling phases; a differential detection unit, responsive to one of the plural parallel received signals, to determine and provide a symbol signal, wherein the symbol signal is determined responsive to one of the plural parallel received signals; a preamble sequence correlator, responsive to the symbol signal, to perform a preamble sequence correlation on the symbol signal to produce a correlator signal, the differential detection unit and the preamble sequence correlator running in serial, plural differential detection units and plural preamble sequence correlators operating in parallel on different branches of the branched received signal to produce plural parallel correlator signals; a map on unit circle unit, responsive to the symbol signal from the differential detection unit, to remove magnitude information from the symbol signal, and provide to the preamble sequence correlator the symbol signal with the magnitude information removed and phase information retained as the symbol signal; a parallel-to-serial unit, responsive to the plural parallel correlator signals, to provide the correlator signal; a metric calculation unit, responsive to the correlator signal, to perform a metric calculation on the correlator signal to produce a calculated metric signal; a packet detection unit, responsive to the calculated metric signal, to determine that a packet is detected and to produce a sample index for the packet detection; and a coarse symbol timing unit, to find a peak of the calculated metric signal and to output a sample index for the peak as coarse symbol timing information; wherein the sample index for the packet detection and the sample index for the coarse symbol timing information are configured for use in processing a physical layer convergence procedure (PLCP) header and physical layer service data unit (PSDU) block and further use in preamble processing.