Title :
Performance analysis of discrete-rate adaptive modulation for OFDM systems with imperfect CSI in Rayleigh fading channel
Author :
Liu, XiaoShuai ; Yu, Xiangbin ; Zhou, TingTing ; Yang, Ying ; Xin, Yin
Author_Institution :
Coll. of Electron. & Inf. Eng., Nanjing Univ. of Astronaut. & Aeronaut., Nanjing, China
Abstract :
Performance of orthogonal frequency-division multiplexing (OFDM) systems with discrete-rate adaptive M-ary quadrature amplitude modulation (M-QAM) in Rayleigh fading channel with imperfect channel state information (CSI) is investigated in this paper. The adaptive scheme used in this paper is to maximize spectral efficiency (SE) subject to a target bit error rate (BER) and fixed power constrain. The fading gain value of each subchannel is partitioned into a number of regions by which the modulation of each subchannel is adapted in terms of the region the fading gain falls in. Based on this adaptive scheme, closed-form expressions of the average SE(ASE) and average BER with perfect and imperfect channel estimation are respectively obtained and confirmed by Monte Carlo simulations. Furthermore, the effect of channel estimation error on the performance of adaptive modulation OFDM system is analyzed.
Keywords :
Monte Carlo methods; OFDM modulation; Rayleigh channels; adaptive modulation; error statistics; Monte Carlo simulations; OFDM systems; Rayleigh fading channel; adaptive scheme; bit error rate; channel state information; closed form expressions; discrete rate adaptive modulation; imperfect CSI; performance analysis; spectral efficiency; Adaptive systems; Bit error rate; Channel estimation; Fading; Modulation; OFDM; Signal to noise ratio; OFDM; adaptive modulation; bit error rate; imperfect channel information; spectral efficiency;
Conference_Titel :
Microwave, Antenna, Propagation, and EMC Technologies for Wireless Communications (MAPE), 2011 IEEE 4th International Symposium on
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-8265-8
DOI :
10.1109/MAPE.2011.6156239
