Data Transmission with Terahertz Communication Systems

Abstract

The need for high bandwidth in wireless systems has been increased because there is always unoccupied bandwidth for the current communication system. Therefore, the extension of communication systems to higher frequencies is required to offer high-capacity wireless applications. In order to achieve high capacity, the carrier frequencies requisite should be increased more than 100 GHz. Nowadays, academics are currently working on wireless communication systems at terahertz (THz) frequency which is attractive for wireless communications since they lead to high capacity. However, the THz channel is a harsh environment for signal transmission. So, the implementation of THz communication system requires the study of modulation schemes. Among various kinds of communication techniques, QPSK and BPSK are suitable due to their simplicity. In this work, quadrature phase shift keying (QPSK) and binary phase shift keying (BPSK) are assumed with incoherent and coherent receiver, respectively. When it comes to opting for the appropriate modulation techniques for THz communication system, there is always a compromise to be made between bandwidth efficiency and power efficiency. For that reason, the performance modulation schemes were analyzed in terms of data rate and power efficiency. Besides, multiple-input multiple-output (MIMO) can provide high capacity by using multiple transmit or receive antennas. This chapter evaluates the performance of QPSK/BPSK modulations for single-input single-output (SISO) and MIMO technics under different values of the roll-off factor considered for root raised cosine (RCC) filter; then we analyze the performance of MRC receiver in MIMO wireless channels with Alamouti encoding at THz frequencies.