With the continuous development of national defense technology, spread spectrum technology is more and more widely used. In order to meet the communication requirements of gun barrel in flight, a transmitter based on spread spectrum technology is designed. The system consists of RF front-end chip AD9361, digital baseband processing chip FPGA and peripheral circuits; The peripheral circuit includes power module, clock module, balun feeder interface, serial port and debug interface. The software of communication system adopts BPSK modulation technology and spread spectrum technology, and the spread spectrum modulation part adopts gold balanced code and three-level RAM buffer scheme. Finally, based on a ballistic measurement project, the telemetry test is carried out, using the ground receiving station to receive the data sent by the transmitter, recording the modulation waveform and calculating the bit error rate of the received data, which verifies the reliability of the designed missile borne transmitter platform and the correctness of the spread spectrum modulation method.