Multi-input Embedded Real-time Software Defined Radio

Abstract

This master thesis work is inspired by the practical aspects of the Analytical Constant Modulus Algorithm (ACMA) proposed by Alle-Jan van der Veen and Arogyaswami Paulraj. The ACMA deals with the beamforming problem associated with constant modulus co-channel signal interference in wireless communication. Co-channel interference occur when multiple signals are transmitted simultaneously at the same frequency from different sources. Beamforming is a technique applied in spatial signal processing to separate out individual signals using an antenna array. ACMA provides an efficient analytical approach to solve beamforming. It is a \textit{blind beamforming} algorithm as it does not require any knowledge of the signals and the channels. The scope of this thesis work is to implement a low cost, low power, embedded Multi-input receiver application. The Multi-input receiver system shall handle partially and fully overlapping constant modulus signals from distinct sources. The signals are modulated using a generic modulation scheme. The Multi-input receiver shall separate out individual signals using the ACMA (blind beamforming) and demodulate each signal. The system shall be software defined such that the beamforming and demodulator are implemented in software on an embedded Digital Signal Processor (DSP) platform. The Multi-input receiver system shall be optimized for the DSP platform in order to achieve real-time performance in terms of speed and stay within the power budget of the system. The receiver shall work efficiently in the presence of interferences and noise such as thermal noise generated by the receiver.