Imposition and Transmission of QPSK Communication Through LabVIEW Using USRP

Abstract

The significance of digital communication has been well accepted all over the world. It has been widely used in wireless networks like satellite communication, and 4G and 5G technologies as it provides high data connectivity and efficiency. For long-distance transmission and reception of signals, maintaining the signal quality is very important and therefore an efficient modulation and demodulation scheme is required. In this paper, the quadrature phase shift keying (QPSK) modulation scheme is being presented. Its several advantages over other digital modulation techniques made it one of the best forms of digital modulation. The concept of software-defined radio has been used as a test bed for implementing QPSK modulation. Simulation of QPSK modulation and demodulation process is performed in Laboratory Virtual Instrument Engineering Workbench software, and the digital transmission and reception of signals are done through Universal Software Radio Peripheral. The signal experiences sampling, quantization, filtering, encoding, modulation, demodulation, decoding, with and without the addition of additive white Gaussian noise on the graphical interface of NI LabVIEW. Several investigations have been done on digital modulation, but they are covered entirely on simulation in any software. In this paper along with the implementation of modulation and demodulation part, the transmission and reception of the signal are also performed using USRP.