FPGA realization of the spread-spectrum communication chip STEL-2000A
Yi Wan · Electronic Design Engineering · 2010
To overcome drawbacks of ASIC such as fixed functionality and upgrade difficulty,FPGA was used to realize the core functions of STEL-2000A.This paper used the DDS IP core provided by ISE to realize the NCO module,called hard core multiplier and implemented CIC filter in the down converter,described the principle and implementation detail of the demodulation of DQPSK,and derived a simple method to introduce a fixed phase shift of π/4.The VHDL source code was designed by modularity method,and the complete system was successfully implemented on Virtex-II Pro development board.Test results indicate that this system successfully realize the core function of the STEL-2000A.