Cluster correlator for a demodulator

A method comprising:

• correlating, in a plurality of first correlators of a first stage of a correlator circuit, a plurality of samples of an input signal comprising a packet, at an oversampling rate, and providing a sample cluster from the plurality of first correlators to a filter;
• producing, via the filter, a processed sample, based on the sample cluster and providing the processed sample to a second stage of the correlator circuit;
• correlating, in a set of second correlators of the second stage of the correlator circuit, the set of second correlators comprising one or more second correlators, the processed sample of a plurality of sample clusters, and outputting a correlation output from the set of second correlators to a timing detection circuit;
• and
• determining, in the timing detection circuit, a timing of the packet based at least in part on the correlation output from the set of second correlators.

A system comprising:

• a receiver to receive a radio frequency (RF) signal, the receiver comprising:
• a RF front end circuit to process the RF signal into a lower frequency signal;
• a baseband processor coupled to the RF front end circuit, the baseband processor comprising:
• a COordinate Rotation Digital Computer (CORDIC) engine to transform the lower frequency signal to a phase signal;
• a differential circuit coupled to the CORDIC engine, the differential circuit to differentiate the phase signal;
• a memory coupled to the differential circuit to store samples of the phase signal;
• a correlation circuit coupled to the differential circuit to receive the samples of the phase signal, the correlation circuit comprising:
• a plurality of first correlators to correlate the samples of the phase signal with a first predetermined pattern and output, during a first switching cycle, a sample cluster comprising an output sample from each of the plurality of first correlators;
• a filter coupled to the plurality of first correlators, the filter to receive the sample cluster and to produce a processed output sample of the sample cluster;
• and
• at least one second correlator coupled to the filter, wherein during the first switching cycle one of the at least one second correlator is to receive a selected output sample from the filter and correlate the selected output sample with a second predetermined pattern, and output a correlation output;
• and
• a demodulator coupled to the memory to demodulate the samples of the phase signal into a demodulated signal.