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From: stan.maciej on 16 Dec 2009 15:59 Hello, I am currently studying the CAZAC sequences and I took a look at the Zadoff-Chu sequence commonly used in LTE. When I perform a time-domain autocorrelation on a 63 sample long Zadoff-Chu sequence with root 29, I get a plot that does not correspond to the autocorrelation plots available in the litterature (LTE The UMTS Long Term Evolution, from Theory to practice by S. Sesia and all. p149). In my plot, the peakto second peak ratio approx 3, comparably to a ratio of 10 in the litterature (my secondary peak are much higher). This is the matlab code I am using to generate the autocorrelation: cazac = zeros(63,1); u = 29; for n=0:62 cazac(n+1) = exp(-1i*pi*u*(n+1)*n/63); end cazac(32) = 0; corrB = xcorr(fft(cazac), fft(cazac)); corrB = corrB/max(corrB); figure(1); time = [-62:62]; plot(time, abs(corrB)); axis([-64 64 0 1]); I would be grateful if somebody could take a quick look at this code and point out what I am doing wrong. I really appreciate your help (I already so much time on this). Thanks, Stan |