Digital Waveform Synthesis For Pcm / Fm Modulation Technique

As the developing of telecommunication, software radio technique is widely applied in various communication modules. In PCM/FM telemetry system, modulation module can be implemented by digital method based on software radio. It is difficult to have ideal result by analog technology because of it's speciality, and that the system is short of flexibility. Compared with analog technology, digital technology can improve the low frequency response of PLL-FM circuit. The stability, flexibility and transmission efficiency of system can be improved by using digital technology too.In this thesis, the digital design of PCM/FM modulation module based on direct waveform synthesis technology is presented.Firstly, we introduce the basic concept ,theory and development of software-defined radio. Chapter three gives the theory and algorithm design of PCM/FM modulation in detail. In chapter four, combined with main function and technology target of the PCM/FM telemetry system, the software algorithm of the design is simulated and proved in full precision by using MATLAB. At the same time ,software and hardware design proved to be feasible by analyzing the debugging result.