Multiple access coding for radio communications

Details Multiple access coding for radio communications Multiple access coding for radio communications

H - Electricity

04

K

H04K 1/04 (2006.01) H04B 1/707 (2006.01) H04J 11/00 (2006.01) H04J 13/00 (2006.01) H04J 13/02 (2006.01) H04L 1/00 (2006.01) H04L 9/00 (2006.01)

Patent

CA 2110995

Individual information signals encoded with a common block error-correction code are assigned a unique scrambling mask, or signature sequence, taken from a set of scrambling masks having selected correlation properties. The set of scrambling masks is selected such that the correlation between the modulo-2 sum of two masks with any codeword in the block code is a constant magnitude, independent of the mask set and the individual masks being compared. In one embodiment, when any two masks are summed using modulo-2 arithmetic, the Walsh transformation of that sum results in a maximally flat Walsh spectrum. For cellular radio telephone systems using subtractive CDMA demodulation techniques, a two-tier ciphering system ensures security at the cellular system level by using a pseudorandomly generated code key to select one of the scrambling masks common to all of the mobile stations in a particular cell. Also, privacy at the individual mobile subscriber level is ensured by using a pseudorandomly generated ciphering key to encipher individual information signals before the scrambling operation.

Affiliated with

Also associated with

Rating

Multiple access coding for radio communications does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Multiple access coding for radio communications, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multiple access coding for radio communications will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1450666