SC-FDMA UPLINK SYSTEM IN HEAVILY FADED AREAS WITH LOW SIGNAL-TO-NOISE RATIO
Subhra Surochita Mishra, Jibendu Sekhar Roy
DOI: 10.15598/aeee.v21i3.4987
Abstract
These Single carrier frequency division multiple access (SC-FDMA) has very low power consumption at the sender’s side, and this is one of the potential candidates for uplink in long-term evolution (LTE). The objective of this work is to explore the error probability of SC-FDMA system under sub-carrier mapping in heavily faded areas where the signal-to-noise ratios (SNRs) are very low. Wireless environment with heavily faded areas includes military radio systems; direct sequence spread spectrum system (DS-SS), global positioning system (GPS) etc. The localized FDMA (LFDMA) and distributed FDMA (DFDMA) are used to compare the performances of SC-FDMA in heavily faded areas. In heavily faded area with negative signal-to-noise ratio (SNR), the SC-FDMA system is implemented using modulation and encoding methods to receive a very weak signal. Here, binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), 16-PSK, quadrature amplitude modulation (QAM) and 16-QAM modulation techniques are used to calculate the bit error rate (BER) performances. The results show the BER performances of SC-FDMA using mapping schemes for different channels, like, AWGN channel, Rayleigh channel, COST207TU, and COST207RA channel models for heavily faded areas. In AWGN channel, BER at -15dB is about 10 times more than BER at 15dB. The COST207 model shows that the BER is less in typical urban (TU) area compared to the rural area (RA).The performance of BPSK modulation in SC-FDMA system is better in heavily faded areas than other modulation schemes.