A Software Radio Receiver with Direct Conversion and Its Digital Processing

This paper discusses a design methodology suitable for the development of software de ned radio platforms. A exible digital receiver was designed and implemented using a multi-port direct converter and an FPGA-based platform. The design starts with a hardware-oriented top-level system model. The model is built based on basic signal processing blocks connected together in a graphical tool. Carrier symbol timing recovery is implemented in the discrete-time (digital) domain with an interpolator-based synchronizer. Carrier phase and frequency are recovered using a feedback synchronization algorithm (a secondorder type-II digital PLL). Experimental results of the platform and its simulations results demonstrate the e ectiveness of the proposed design methodology. key words: Software de ned radio, direct conversion, design methodology.