Channel Assignment for Multihop Cellular Networks: Minimum Delay

Multihop cellular networks (MCNs) enhance the capacity and coverage and alleviate the dead-spot and hot-spot problems of cellular networks. They also allow faster and cheaper deployment of cellular networks. A fundamental issue of these networks is packet delay because multihop relaying for signals is involved. An effective channel assignment is the key to reducing delay. In this paper, we propose an optimal and a heuristic channel assignment scheme, called OCA and minimum slot waiting first (MSWF), respectively, for a time division duplex (TDD) wideband code division multiple access (W-CDMA) MCN. OCA provides an optimal solution in minimizing packet delay and can be used as an unbiased or benchmark tool for comparison among different network conditions or networking schemes. However, OCA is computationally expensive and, thus, inefficient for large real-time channel assignment problem. In this case, MSWF is more appropriate. Simulation results show that MSWF achieves on average 95 percent of the delay performance of OCA and is effective in achieving high throughput and low packet delay in conditions of different cell sizes.