Generalized Joint Power and Rate Adaptation in DS-CDMA Communications Over Fading Channels

• Published in: IEEE transactions on vehicular technology Vol. 57; no. 1; pp. 603 - 608
• Main Authors: Lee Ye Hoon, Lee Ye Hoon, Kim Sang Wu, Kim Sang Wu
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.01.2008; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptation; Adaptive systems; Applied sciences; Channel state information; Channels; Code division multiple access; Data analysis; direct-sequence code division multiple access (DS-CDMA); Electrical engineering. Electrical power engineering; Electrical power engineering; Exact sciences and technology; Fading; Gain; joint power and rate; Multiaccess communication; Nakagami fading; Narrowband; Operation, maintenance, reliability; Operation. Load control. Reliability; Performance enhancement; Power control; Power networks and lines; Quality of service; Real numbers; Senior members; Spreading; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Teletraffic; Throughput; Transmission and modulation (techniques and equipments); Transmitters; DS/CDMA; Nakagami fading; joint power and rate; adaptive systems; Fading channels; Performance evaluation; Adaptive systems; Adaptive system; Flow rate regulation; Wireless telecommunication; Transmission channel; Information rate; Teletraffic; Information transmission; direct-sequence code division multiple access (DS-CDMA); Traffic management; Code division multiple access; Traffic control; Peak power; Service quality; Direct sequence; Gain
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2007.905345

We propose a generalized joint power and rate adaptation scheme in direct-sequence (DS) code-division multiple-access (CDMA) communications over Nakagami fading channels. The transmission power allocated to user is proportional to G i p , where G i is the channel gain of user i and p is a real number, and the data rate (i.e., spreading gain) is jointly adapted so that a desired QoS is maintained. We analyze the average data rate of the proposed adaptation scheme subject to fixed average and peak transmission power constraints. Our results show that the proposed joint adaptation scheme provides a significant performance improvement over power-only and rate-only adaptation.