Title :
Performance of cellular DS/CDMA systems employing power control under slow Rician/Rayleigh fading channels
Author :
Hashem, Bassam ; Sousa, Elvino
Author_Institution :
Dept. of Electr. & Comput. Eng., Toronto Univ., Ont., Canada
Abstract :
Power control is essential for CDMA cellular systems to overcome the near far problem. Fast power control tracks multipath fading perfectly which increases the intercell interference and thus reduces the capacity. If there is a line of sight (LOS) component between the mobile and the base station with which it is communicating, the fading will be of Rician type and less deep fades will be encountered which reduces the intercell interference. In this paper, we investigate the system capacity assuming the fading between a mobile and the base station with which it is communicating to be Rician with a Rician factor K while the fading between the same mobile and other base stations to be Rayleigh. We show a large increase in the capacity even for small Rician factors. A Rician fading is usually encountered when the mobile is close to the base station and thus the path-loss exponent can be less than four. Thus, we investigate the effect of changing the path-loss exponent value on the system capacity. Finally, we reduce the intercell interference by imposing a limit on the maximum increase in power to compensate for multipath fading and show how can this increase the capacity by more than 100%
Keywords :
Rayleigh channels; Rician channels; cellular radio; channel capacity; code division multiple access; multipath channels; power control; radiofrequency interference; spread spectrum communication; telecommunication control; LOS component; Rician factor; base station; cellular DS/CDMA systems; intercell interference; multipath fading; near far problem; path-loss exponent; performance; power control; slow Rician/Rayleigh fading channels; system capacity; Base stations; Fading; Interference; Multiaccess communication; Power control; Power system modeling; Rayleigh channels; Rayleigh scattering; Rician channels; Shadow mapping;
Conference_Titel :
Spread Spectrum Techniques and Applications, 1998. Proceedings., 1998 IEEE 5th International Symposium on
Conference_Location :
Sun City
Print_ISBN :
0-7803-4281-X
DOI :
10.1109/ISSSTA.1998.723819