Title :
Performance evaluation of adaptive OFDM systems in time-varying channels
Author :
Haixia Zhang ; Dongfeng Yuan ; Ci Song ; Xinying Gao
Author_Institution :
Sch. of Inf. Sci. & Eng., Shandong Univ., China
Abstract :
One of advantages of the OFDM transmission technique is that it has the inherent flexibility to adapt the modulation scheme on each subcarrier according to the signal-to-noise ratio (SNR) on the subcarrier, leading to an adaptive OFDM (AOFDM) system. We proposed a coded AOFDM system in a time-varying channel. By choosing an optimal M-QAM modulation scheme used by a subcarrier on the instantaneous channel knowledge, we extensively investigate the bit-error-rate (BER) performances of AOFDM systems with different vehicle speeds, modulation schemes and bit rates under Rayleigh fading channels.
Keywords :
OFDM modulation; Rayleigh channels; adaptive modulation; error statistics; mobile radio; modulation coding; quadrature amplitude modulation; time-varying channels; BER; M-QAM modulation scheme; Rayleigh fading channels; SNR; bit-and-power allocation; bit-error-rate; coded adaptive OFDM systems; instantaneous channel knowledge; signal-to-noise ratio; time-varying channels; vehicle speed; Adaptive systems; Bit error rate; Bit rate; Channel capacity; Fading; Intersymbol interference; OFDM modulation; Signal to noise ratio; Time-varying channels; Vehicles;
Conference_Titel :
Communications, Circuits and Systems, 2004. ICCCAS 2004. 2004 International Conference on
Conference_Location :
Chengdu
Print_ISBN :
0-7803-8647-7
DOI :
10.1109/ICCCAS.2004.1346080
