Howtosignalprocessing
What is orthogonal codes in CDMA?
An optical orthogonal code (OOC) is a family of (0,1) sequences with good auto- and cross-correlation properties; they are used as a means to obtain code division multiple access (CDMA) on fiber optic networks. Previous work on OOC has assumed that the weight of each codeword is the same.
What is spreading in CDMA?
A spreading sequence is a binary sequence that appears random but can be reproduced in a deterministic manner by intended receivers. These spreading sequences are used to encode and decode a user's signal in asynchronous CDMA in the same manner as the orthogonal codes in synchronous CDMA (shown in the example above).
How do you implement CDMA?
Techniques generally used are direct sequence spread spectrum modulation (DS-CDMA), frequency hopping or mixed CDMA detection (JDCDMA). Here, a signal is generated which extends over a wide bandwidth. A code called spreading code is used to perform this action.
