This article gives a brief tutorial on transform-domain communication system (TDCS), OFDM, and MC-CDMA. The primary goal of this article is to give a detailed description of the TDCS transmitter and receiver systems and to highlight the fundamental differences relative to OFDM and MC-CDMA. The fundamental idea in TDCS is to synthesize a smart adaptive waveform to avoid interference at the transmitter instead of the more traditional mitigating of interference at the receiver. Unlike OFDM and MC-CDMA, TDCS has very little exposure in the current literature.

No abstract

This paper reports the impact of digital signal processing on microwave receiver technology. The majority of modern receiver designs are based on digital technology. Wideand narrow-band receivers will be presented. The wide-band receivers cover approximately 1-GHz instantaneous bandwidth and are used to intercept radar pulses. Current narrow-band receivers cover up to 50-MHz instantaneous bandwidth and are primarily used for receiving communication signals. Two approaches for wide-band receiver design will be discussed. One is the conventional digital receiver. The other one is called the monobit receiver, which has slightly inferior performance in some respects, but can be built on a single chip. Narrow-band receivers are best implemented in software because they can more adapt to changes. Two types of receivers will be discussed. One is the software global positioning system receiver. The other one is called a transform-domain communication system. The object of this system is to avoid interference in a hostile communication environment.