iam doing BPSK transmission and receiving with acoustic signals, in order to get my actual signal from my received signal I am using xcorr in matlab to find peak point of alignment and getting my signal from that, but I am having issues the maximum seems to be not one point but a long range of points. Can anyone tell me why this is happening and how I can ensure the maximum occurs at one point or a better way to find the starting point of the signal, Thanks? i must also mention each bit has about 8000 samples there are o23 bbits in the received signal
Looking to your correlation plot and trying to infer what you have I came with the following hypothesis (1) the signal is not uncorrelated, this is why you have multiple peaks, it looks like the signal is periodic, you can check this doing the correlation of the signal with itself; (2) One of the signals is shortest, if the signals are of the same size correlation tends to be larger in the middle of the plot. Either way, the similar peaks will be equally good alignments.