Patent ID: 8184755

Claim:
A method for performing symbol boundary synchronization in a communication system, the method comprising: generating a symbol alignment estimate from a partial signal correlation by: identifying symbols in a transmitted signal as a sum of a periodic known signal and a random signal; characterizing a cross-correlation of a channel output with the periodic component of the transmitted signal as a sum of a first convolution and a second convolution, the first convolution being a cross-correlation between two partial sequences, the second convolution being an estimate of an effective channel impulse response; and determining the symbol alignment estimate based in part on at least one of the cross-correlation of the channel output with the periodic component of the transmitted signal or known constellation points; refining the symbol alignment estimate via a carrier phase calculation, the refining including: determining a respective carrier phase of each of two adjacent carriers, the two adjacent carriers including a first carrier at frequencies f 1 =p*f 0 and a second carrier at frequencies f 2 =(p+1)*f 0 =f 1 +f 0 , f 0 being a discrete multi-tone (DMT) fundamental frequency and p being a positive integer; determining a phase error based at least in part on a carrier phase difference between the two adjacent carriers as directly proportional to an offset from the start of a symbol of a block of the symbols; determining a phase difference contribution due to a communication channel and hardware; counter-rotating the determined carrier phase of the first carrier and the second carrier based on an angle of a constellation point at a transmitter, wherein an estimate of the offset, δ, is expressed as δ=(NΔφ offset )/(2π)−k c in an event that the offset resulting from the phase difference due to the communication channel and hardware phase response is k c , N being a symbol length, Δφ offset being a compensated phase error of the first carrier and the second carrier; and refining the symbol alignment estimate based in part on the compensated phase error.