Continuous Phase Modulation (cpm) Technology

Modulation technology is a critical technology in communication system. The performance of communication system is influenced by the model of modulation system to a large extent, especially to digital communication system. Adopting high -performance modulation technology contributes to the increase of spectral density.First, several traditional modulation models such as AM, FM have been analyzed and compared in the thesis. These analyses pointed that AM, FM are not adapted to fading multipath channel in wireless mobile communication system. But CPM(Continuous-Phase Modulation) adapts to the channel by means of its high spectrum ratio fortunately. So the CPM is an advanced modulation technology. It is very necessary for us to research the CPM modulation technology.The basic principle on CPM has been expatiated in the thesis according to collecting literatures. The tasks have been accomplished as follows:.Established CPM system frame. Among them some important designs process has been realized..The flowchart for CPM has been designed. The simulation programs of CPM modulation system (including modulator and demodulator) have been realized with MATLAB. All simulation programs can simulate the process from modulation to demodulation. So the research work has made progress essentially..The simulation programs for CPM have been debugged andexamined in order to validate the correctness.. The influences of modulation index to spectral bandwidth have been researched, so the result is significative to choose modulation index.