Title :
Performance enhancement of DS-CDMA system using overlapping sectors with interference avoidance
Author :
Ng, Benjamin K. ; Sousa, E.
Author_Institution :
Dept. of Electr. & Comput. Eng., Toronto Univ., Ont., Canada
Abstract :
A cellular system with overlapping sectors is proposed to enhance system performance through interference avoidance. In such system, users lie within the coverage of more than one sector, yet each user only chooses one sector for signal transmission and reception. The choices of sectors among different users affect the interference level experienced by others. It is shown in this paper that their mutual interference is minimized by choosing a good sector combination. We investigate the potential benefits of proposed technique in two scenarios: an orthogonal and a non-orthogonal CDMA system. In the former case, spreading code allocation combined with sector selection reduces the required number of code to support all users compared to conventional non-overlapping sector system. For the non-orthogonal CDMA system, the enhancement takes the form of multiple access interference reduction. Simulations results show that its improvement is pronounced and can be further enhanced by increasing the number of overlapping sectors
Keywords :
cellular radio; code division multiple access; frequency division multiple access; interference suppression; multiuser channels; radiofrequency interference; spread spectrum communication; time division multiple access; DS-CDMA system; cellular system; hybrid F/CDMA system; hybrid T/CDMA system; interference avoidance; multiple access interference reduction; mutual interference minimization; nonorthogonal CDMA system; orthogonal CDMA system; overlapping sectors; performance enhancement; sector selection; signal reception; signal transmission; simulations results; spreading code allocation; Antenna arrays; Costs; Councils; Directional antennas; Electronic mail; Filtering; Multiaccess communication; Multiple access interference; Power control; System performance;
Conference_Titel :
Spread Spectrum Techniques and Applications, 2000 IEEE Sixth International Symposium on
Conference_Location :
Parsippany, NJ
Print_ISBN :
0-7803-6560-7
DOI :
10.1109/ISSSTA.2000.878087
