Digital quadrature demodulation of multiple RF signals

Abstract

The software defined radio (SDR) is an important research topic in the area of modern communications. Digital quadrature demodulation is a potential approach to design SDR systems. It is well known that the complexity of the digital quadrature demodulator (DQD) can be significantly reduced by using the quadrature sampling technique. To fully exploit the capability of the SDR, a simple method for digital quadrature demodulation of multiple radio frequency (RF) signals using a single receiver front-end would be appreciated. The conventional quadrature sampling technique, however, is suited only for a single RF signal. In this paper, we develop a novel technique for quadrature sampling of multiple RF signals. Based on this technique, a DQD for multiple RF signals is proposed. SDR systems can benefit from the proposed method.