Abstract
To address the digital divide in developing countries, fixed wireless access (FWA) networks have the potential to quickly provide economical access over a wide area within a radius of tens of kilometers. The conventional synchronous variable-multiple collision avoidance (v-MCA) system, which is referred to as a non-precedence (NP) system, can be operated over a network of any size without the need to use frame-length restrictions. However, it has a potential drawback of rapid degradation of the throughput due to the intervention of the round trip time, which is proportional to the network length and upload bandwidth. The advanced synchronous v-MCA system incorporating total precedence (TP) transmission of frames provides high throughput regardless of network length and upload bandwidth. In this paper, after showing the medium access control mechanisms of the NP and TP systems, their theoretical calculation models are discussed in detail. Then, their system performances are evaluated and overlooked by comparing theoretical and simulated results. The TP system provides an ultimate maximum throughput performance regardless of network length and total upload bandwidth, while maintaining the low delay characteristics of a contention-based access scheme.
