Solving the near-far problem in CDMA-based ad hoc networks

Alaa Muqattash, Marwan Krunz, William E. Ryan

Research output: Contribution to journalArticlepeer-review

45 Scopus citations


In this paper, we propose a distributed CDMA-based medium access protocol for mobile ad hoc networks (MANETs). Our approach accounts for multiple access interference (MAI) at the protocol level, thereby addressing the notorious near-far problem that undermines the throughput performance in MANETs. Collision avoidance information is inserted in the clear-to-send (CTS) packets and broadcasted over an out-of-band control channel. This information is used to dynamically bound the transmission power of possible interfering nodes in the vicinity of a receiver. Data packets are transmitted at a power level such that interference-limited simultaneous transmissions can take place in the vicinity of a receiving terminal without disturbing its reception. Simulation results indicate that the proposed protocol achieves a significant increase in network throughput relative to the 802.11 approach, at no additional cost in energy consumption. Finally, we show that variable processing gain may be used to increase the capacity of the proposed protocol.

Original languageEnglish (US)
Pages (from-to)435-453
Number of pages19
JournalAd Hoc Networks
Issue number4
StatePublished - Nov 2003


  • 802.11
  • Ad hoc networks
  • CDMA
  • Multiple access interference
  • Near-far problem
  • Power control
  • Spread spectrum
  • Variable processing gain

ASJC Scopus subject areas

  • Software
  • Hardware and Architecture
  • Computer Networks and Communications


Dive into the research topics of 'Solving the near-far problem in CDMA-based ad hoc networks'. Together they form a unique fingerprint.

Cite this