The Exploration of the Software-Defined Radio Concept by Prototyping Transmitter and Receiver Functions on a Digital Signal Processor

An ideal software radio is a system that performs analog-to-digital conversion directly after the antenna and then does all signal processing required in the digital domain on a platform that supports reconguration. Software-defined radio (SDR) is the term used for a more realistic approach in which part of the processing is still done in the analog domain. The use of mobile telephony has shown a spectacular growth in the last 10 years. A side eect of this rapid growth is an excess of mobile system standards. Therefore, the SDR concept is emerging as a potential pragmatic solution. It aims to build flexible radio systems, which are multipleservice, multi-standard, multi-band, re-congurable and reprogrammable, by software. First, this paper presents a global overview of SDR. Furthermore, it explains the implementation of an SDR transmitter and receiver that have been simplied for the purpose of illustration. The source code has been written in C and is running on a DSP evaluation module of Texas Instruments. The algorithms are based on a modied version of the China Wireless Telecommunication Standard (CWTS). The correctness of the implemented system has been verified and measurements of the bit error rate versus the bit-energy-to-noise-energy ratio are reported.