CORDIC based reconfigurable architecture for DS-CDMA/CI transmitter

The traditional model of DS-CDMA transmitter is not efficient when spreading codes are complex since complex multiplications needed for spreading would consume more power, require more area for implementation and incur more delays. In this paper, a novel architecture for DS-CDMA/CI transmitter is proposed which uses CORDIC algorithm to generate carrier whose phase offset is controlled by Carrier Interferometry (CI) codes. The architecture is based on the principle that product of two exponential is essentially an exponential with angle equal to sum of angle of product components. Furthermore, the architecture is reconfigurable in the sense that the spreading codes can be dynamically assigned during transmission and therefore can be used for designing communication systems for cognitive radio applications. The maximum frequency of operation was found to be 22 MHz from timing analysis results for given model for SPARTAN 3E FPGA.