Optimality of greedy power control and variable spreading gain in multi-class CDMA mobile networks

Seong Jun Oh, Kimberly M. Wasserman

Research output: Chapter in Book/Report/Conference proceedingConference contribution

42 Citations (Scopus)

Abstract

In this paper, we consider a DS-CDMA mobile network supporting real-time and non-real-time services. We study how the delay tolerance of non-real-time traffic can be exploited to allow both transmission power control and variable spreading gain (transmission rate control) as mechanisms to optimally adapt the received energy per bit to the current channel conditions and efficiently manage the multiple access interference so as to optimize performance. We provide the jointly optimal power and spreading gain allocation strategy that maximizes non-real-time throughput subject to constraints on peak transmission power and maximum interference generated by non-real-time sources. We show that under the optimal strategy, the optimal spreading gains are inverse linear in the signal to interference plus noise ratio (SINR), and transmission power is allocated to the non-realtime sources in decreasing order of channel gain according to a greedy control strategy: The sources with the highest quality channels transmit at maximum power, while the sources with the lowest quality channels do not transmit. The number of non-real-time sources permitted to transmit simultaneously decreases as the peak transmission power increases, and there is at most a 3 dB difference in SlNR between permitting all sources to transmit and permitting only one source to transmit. We also present numerical results comparing the throughput and delay performance of the optimal strategy with other common strategies; the optimal strategy can offer substantial performance gains.

Original languageEnglish
Title of host publicationMobiCom 1999 - Proceedings of the 5th Annual ACM/IEEE International Conference on Mobile Computing and Networking
PublisherAssociation for Computing Machinery
Pages102-112
Number of pages11
ISBN (Electronic)9781581131420
DOIs
Publication statusPublished - 1999
Externally publishedYes
Event5th Annual ACM/IEEE International Conference on Mobile Computing and Networking, MobiCom 1999 - Seattle, United States
Duration: 1999 Aug 151999 Aug 19

Publication series

NameProceedings of the Annual International Conference on Mobile Computing and Networking, MOBICOM
Volume1999-August

Conference

Conference5th Annual ACM/IEEE International Conference on Mobile Computing and Networking, MobiCom 1999
Country/TerritoryUnited States
CitySeattle
Period99/8/1599/8/19

ASJC Scopus subject areas

  • Computer Networks and Communications
  • Hardware and Architecture
  • Software

Fingerprint

Dive into the research topics of 'Optimality of greedy power control and variable spreading gain in multi-class CDMA mobile networks'. Together they form a unique fingerprint.

Cite this