| abstract |
This invention provides a code division multiplexing method and system which include the following steps: constructing the basic grouping perfect orthogonal complementary code pair mate, modulating the C code and S code of the basic grouping perfect orthogonal complementary code pair mate to the M orthogonal carrier frequency or orthogonal polarization waves which are serially in time, and implementing continuous shift on the modulated basic grouping perfect orthogonal complementary code pair mate. The present invention's code division multiplexing method and system make each carrier signal's average time bandwidth product approach to 1 by using orthogonal multicarrier, having the code utilization rate more than 1 through the shift overlapping under the condition of keeping the property of signature sequence groups' “zero related window” and making the signature sequence word's utilization rate far greater than 1 by using shift overlapping under the condition of losing the “zero related window” property of signature sequence but keeping the property of signature sequence groups' orthogonality. Therefore, the system has greater spectrum efficiency even if just using low dimensional modulation signals. |