Patent attributes
Method for reducing the chip rate of Code Division Multiple Access (CDMA) codes uniformly spread over a frequency bandwidth by converting these codes to 2-scale codes which perform uniform spreading within the subbands of a filter bank over the bandwidth, and over the subbands, and with controllable subband power levels. This is a 2-scale code example of Multi-Scale Code Division Multiple Access (MS-CDMA) and assigns algebraic fields of indices for the first scale “0” which spread within each subband and algebraic fields of indices for the second scale “1” which spread over the subbands. These algebraic fields are scaled and combined to form the algebraic fields of code and chip indices for the 2-scale code. These 2-scale codes perform a Wavelet dilation type of operation to stretch the CDMA chips while maintaining the spreading over the full frequency band.
