Performance Analysis of QPSK & QAM Modulation Schemes for Long Term Evolution 4G Communication Standard

Abstract

Long Term Evolution (LTE) is the fourth-generation (4G) communication standard specified by third Generation Partnership Project (3GPP). The LTE standard deploys higher modulation schemes such as QPSK & QAM. These techniques along-with OFDM are widely utilized in LTE systems. The objective of this paper is to analyse and compare QPSK, 16-QAM, 64-QAM modulation techniques for different values of Signal to Noise Ratio (SNR). The simulation of these techniques is carried out in the environment of MATLAB R2018b for the downlink channel. In the set up, the enhanced node base station uses transmission bandwidth of 20 MHz & 2/3 coding rate for 4X4 MIMO. The simulation is done at 5 dB, 10 dB, 15 dB & 20 dB SNR. It is found that, constellation  diagram becomes distorted at low SNR and performance of the systems becomes inadequate in terms of high Bit Error Rate (BER) & Packet Error Rate (PER). As SNR is increased, both PER & BER get improved. Simulation results also show that the received signal quality becomes better in terms of constellation diagram of modulation schemes at high SNR. It is observed that data rate of 7.78 Mbps is achieved for QPSK, while for 16-QAM & 64-QAM, the data rate is found to be 15.14 Mbps and 22.8 Mbps respectively.

Keywords- LTE, 4G, QPSK, 16-QAM, 64-QAM, BER, PER  

Cite this Article

Shreya Khandelwal, Gulrej Ahmed, Arjun Singh. Performance Analysis of QPSK and QAM Modulation Schemes for Long-Term Evolution 4G Communication Standard. Recent Trends in Parallel Computing. 2019; 6(2): 27–37p.