walsh code

IN cdma2000 , what's difference between PN , walsh coed , long code and short code? how to work in forward and reverse channel?

The difference is correlation, PN code has a good cross correlation but its autocorrelation is bad. Walsh code has a good autocorrelation but it cross correalation is bad I think. Good autocorrelation is for detection. Good cross correlation is good for multiuser environment.

PN cod have a good autocorrelation, and Walsh cod have good cross correlation.

Then tell me how to use on the forward / reverse channel for PN and Walsh code?

Hi xinxin

in cdma,
Walsh code is for chanelization
short PN code is for identifying the BTS
long PN code is for identifying the MS
all PNs and Walsh code are orthogonal code

hope this help

Thinh

IN CDMA for spreading we dont use orthogonal codes like walsh code because it has poor cross correlation as well as auto correlation....when codes are out of sync...