A Novel Bus Lane Scheme for QoS Routing in Mobile Ad Hoc Networks

Ad hoc networks are multihop wireless networks without fixed infrastructure, whose topology changes frequently and unpredictably. How to issue routes in such networks with sufficient and constant bandwidth is a key problem for some real-time services like audio and video services. This paper proposes a novel QoS solution using code division multiple access (CDMA) scheme, named CDMA Bus Lane, which combines the network layer with lower layers together to set up and reserve an interferencefree path dynamically for each real-time flow according to its bandwidth requirements. The bandwidth calculation and the channel spreading code assignment method are introduced particularly in this paper. The code used in the Bus Lane scheme is the Original Variable Spreading Factor (OVSF) code. Also an on-demand routing algorithm has been proposed to calculate and reserve the bandwidth hop by hop from source to destination. KeywordsAd hoc networks, QoS routing, CDMA Bus Lane, OVSF, code assignment, real-time traffic