long PN sequence' usage in CDMA

Started by Laron September 9, 2009
Hi all,
     there always said long PN sequence(period 2^n-1) got a small
cross-correlation  property as -1/(2^n-1). But in practice, one symbol
could only be spread by a small amount(128 etc) but not 2^n-1, so how can
we guarantee the cross correlation property -1/(2^n-1)? Thanks.

B. R.