On improving network connectivity by power-control and code-switching schemes for multihop packet radio networks

Packet radio network (PRN) consists of low or even no mobility stations each assigned with a code to prevent transmission from collision. A PRN with strong connectivity will help to reduce the route length and provide more alternatives for routing, improving the overall throughput and end-to-end delay. With power control mechanism, each station could be assigned with a power level to change the neighborhood relation and improve network connectivity. Assigning high transmitting power level to a station can enhance the network connectivity but may increase the number of neighbors, raising collision problem for parallel transmissions among neighbors. How to assign appropriate power level to improve the network connectivity with a constraint of limited codes is one of the most important issues in PRNs. Given a network topology and a set of codes that has been assigned to stations, the proposed power control and code switching mechanism assigns each station with a power level and a code to improve the network connectivity. Based on the matrix-based operation, the power control and code switching metrics in network connectivity problem are generally identified and efficiently resolved. Simulation study reveals that the proposed mechanism increases network throughput and provides a variety of route selection thus improves the performance of a given PRN.