Title :
Adaptive Rayleigh fading compensation for coherent GMSK signals in digital mobile communications
Author :
Leng, Xue Feng ; Leung, Patrick S K
Author_Institution :
Dept. of Electr. & Electron. Eng., Victoria Univ. of Technol., Melbourne, Vic., Australia
Abstract :
A new fading compensation scheme for coherent Gaussian minimum shift keying (GMSK) in a fast Rayleigh fading mobile environment is described. The proposed scheme employs the adaptive extended Kalman filter (EKF) and a new decision-aided predictive algorithm to achieve accurate channel fading estimation and cancellation even when the Doppler spread is large. Our study shows that the proposed scheme requires only 18 dB Eb/No to achieve a bit error rate (BER) of Pe=10-2 which is within 2 dB of the theoretical GMSK performance in a mobile channel with normalised Doppler spread of fDT=6.25×10-3. The corresponding E b/No requirement for the conventional Costas loop coherent receiver is 28 dB. In addition, the proposed scheme achieves a residual error rate which is more than one order of magnitude lower than that of the conventional receivers. Our scheme is particularly attractive for mobile communications where a high Doppler spread is expected
Keywords :
Doppler effect; Gaussian channels; Rayleigh channels; adaptive Kalman filters; coherence; compensation; digital communication; fading; minimum shift keying; mobile communication; phase locked loops; Costas loop coherent receiver; Doppler spread; accurate channel fading estimation; adaptive Rayleigh fading compensation; adaptive extended Kalman filter; bit error rate; channel cancellation; coherent GMSK signals; coherent Gaussian minimum shift keying; decision-aided predictive algorithm; digital mobile communications; residual error rate; Bandwidth; Degradation; Fading; Frequency modulation; Gaussian noise; Intersymbol interference; Low pass filters; Mobile communication; Prediction algorithms; Rayleigh channels;
Conference_Titel :
Vehicular Technology Conference, 1994 IEEE 44th
Conference_Location :
Stockholm
Print_ISBN :
0-7803-1927-3
DOI :
10.1109/VETEC.1994.345122