Implementation Of Intermediate Frequency Modem Of Software Defined Radio Transmitter-receiver

Software Defined Radio uses updatable and reconfigable application software as possible to implement variable kinds of radio function; it makes features of flexibility, compatibility and an open architecture. Our object is an intermediate frequency modem of a software defined radio transmitter-receiver of multi-service, multi-modulationmode and multi-processdatarate. First, related software defined radio theory is introduced; later, channels of transmitter-receiver are designed with consideration of data format, modulation, FEC, interwaving. and scrambling; emphasis is placed on theory and implementation of an audio compression algorithm CVSD(Continuous Variable Slope Delta Modulation) and a FEC technique Convolutional Coding-Decoding. Finally the program framework is established and the practical intermediate frequency modem of a software defined radio transmitter-receiver is realized on DSP centric hardware platform.