Digital Phase Modulation Systems, Frequency Hopping Transmission Mode

Recently, frequency-hop communication has been widely used in many military wireless communication domain as a secure transmission mode. In frequency-hop transmission, phase modulation system has good performance and high frequency efficiency. Phase modulation system is a superior system, can transmit data at high rate. In this thesis, digital FH - MPSK andFH-π/4DQPSK modulator and demodulator are given according to the frequency-hopcommunication characteristics. At last, we implement these systems in both hardware and software platform.Chapter 1 is an introduction to the frequency hopping, including its characteristics, structure, current technical situation and future tendency. In this chapter, software radio which has good compatibility and expansibility is introduced farther.Chapter 2 treats the design of digital phase modulation system in frequency hopping mode communication. At first, a description of channel characteristics is given for the latter design. Then, the frequency-hop system is presented. Emphasis is placed on the analysis of effect on the phase modulation system which is produced in frequency-hop transmission. At last, we scheme out theFH-MPSK and FH-π/4DQPSK systems according to the frequency-hop communication characteristics.Chapter 3 discusses the modules used in the FH-MPSK and FH-π/4DQPSKsystems. These modules include: DUC/DDC (Digital Up Converter / Digital Down Converter), Nyquist flitter, burst start detection, interpolation module, PLL (phase locked loop), PLL error extraction, initial phase correction and the coding and decoding for TCM.In chapter 4, the hardware and software implemented results are shown. We simulated the FH-MPSK and FH-π/4DQPSK systems by matlab, and implement them on a Texas Instruments chip TMS320C6416.