Collision Avoidance in Single-Channel Ad Hoc Networks Using Directional Antennas

Abstract

Three collision-avoidance protocols are analyzed that use omni-directional packet reception together with omni-directional transmissions, directional transmissions, or a combination of both. A simple model is introduced to analyze the performance of these collision avoidance protocols in multi-hop networks with arbitrary topologies. The numerical results of this analysis show that collision avoidance using a narrow antenna beamwidth for the transmission of all control and data packets achieves the highest throughput among the three collision avoidance schemes considered. Simulation experiments of the popular IEEE 802.11 MAC protocol and its variants based on directional transmissions and omni-directional packet reception validate the results predicted in the analysis. The results further show that narrow-beamwidth transmissions also can reduce the average delay experienced by nodes. It is concluded that the advantage of spatial reuse achieved by narrow-beamwidth transmissions outweighs that of conservative collision avoidance schemes featured by the omni-directional transmission of some control packets. This is because the latter requires far more stringent coordination of nodes with their neighbors and hidden terminals, which can lead to much more channel resource wasted due to nodes' excessive waiting time.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2003
Accession Number
ADA459325

Entities

People

  • J.J. Garcia-Luna-Aceves
  • Yu Wang

Organizations

  • University of California, Santa Cruz

Tags

Communities of Interest

  • Counter WMD
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Ad Hoc Networks
  • Antennas
  • Collision Avoidance
  • Collisions
  • Directional
  • Directional Antennas
  • Markov Chains
  • Mesh Networks
  • Network Topology
  • Networks
  • Orientation (Direction)
  • Probability
  • Simulations
  • Simulators
  • Steady State
  • Steerable Antennas
  • Throughput

Fields of Study

  • Computer science

Readers

  • Computer Networking
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering