Capacity improvement of a hybrid CDMA/WDMA system by various bandwidth allocations

We propose a hybrid CDMA/WDMA LAN architecture. The CDMA scheme is based upon spectral coding. For CDMA, the system performance will be improved greatly by increasing the code length so that it can accommodate more users. We calculate the system capacity under three types of code length, namely 128, 256, and 512. When the proportion of usable bandwidth that is allocated to CDMA users is decreased, the total number of users of hybrid system will decrease but the total bit rate will increase. 100 GHz and 50 GHz are used as the adjacent channel spacing of WDMA.