Abstract:The design method is given for the digital piecewise linear mapping system based on FPGA chip. In this method, the perturbation of m-sequence is used to overcome the short period of chaotic sequence caused by the finite precision effect. The piecewise linear chaotic generator is realized by means of VHDL and the simulations are made. The balance, the correlation and the linear complexity are compared between digital chaotic sequence and analogue chaotic sequence. A road is explored to apply the piecewise linear mapping system to a practical spreading spectrum system.