Patent ID: 8139699

Claim:
A process for preamble detection in a plurality of baseband receive data streams having at least one preamble of length N, the process having: a first step of delaying said receive data stream by an amount substantially equal to N/3, thereby producing a first delay output; a second step of delaying said first delay output by an amount substantially equal to N/3, thereby producing a second delay output; a third step of multiplying each conjugated second delay output by said first delay output to generate a first multiplier output; a fourth step of multiplying each conjugated first delay output by said receive data stream to generate a second multiplier output; a fifth step of accumulating said first multiplier output by subtracting said second multiplier output from said first multiplier output, thereafter forming a magnitude output from said accumulator output; a sixth step of summing all of the magnitude outputs and comparing the sum with a first threshold, asserting a preamble detect when said sum exceeds said first threshold.