Gao, Hongju. Performance evaluation of multi-hop WPANS based on a realistic OFDM UWB physical layer. Retrieved from https://doi.org/doi:10.7282/T3V988JG
DescriptionMB-OFDM (Multi-Band Orthogonal Frequency Division Multiplexing) is one of the promising candidates for the UWB (Ultra-Wide-Band)-based alternative physical (PHY) layer for WPANs (Wireless Personal Area Networks). However, the coverage radius of MB-OFDM UWB systems is very short, and single-hop transmissions may not be adequate for WPANs operating at very high-data-rates. Therefore, a multi-hop ad hoc WPAN system is considered in this study in order to extend the UWB radio coverage. The overall system performance is obtained to determine if the Quality-of-Service parameters can still be preserved when an IEEE 802.15.3 TDMA MAC layer is used in multi-hop communication scenarios.
A position-based stateless routing protocol with greedy forwarding is adopted in this study for multi-hop WPANs. Simulation results show that the position-based stateless greedy routing scheme with carefully selected transmission radius R meets the QoS performance criteria for many real-time applications before saturation of the network occurs. Hence, the scheme is a good choice for the routing protocol to be used with multi-hop WPANs based on an OFDM UWB physical layer.
At the MAC layer, when using equal-weighted topology-based scheduling, it can be observed that the system performance obtained can meet QoS requirements only when either the data rate is very low, or there are only a very small number of active links. Network capacities actually achieved for both 200 and 480 Mbps transmission systems are much less than those predicted by theory since the network bandwidth is not utilized efficiently. When using the on-demand rate-based scheduling scheme, the performance results for both the 200 and 480 Mbps transmission systems match the network capacity levels expected for multi-hop WPANs. The scheduling efficiency is comparatively high for the on-demand scheduling scheme, and hence, network bandwidth can be utilized more efficiently. It has been found that the IEEE 802.15.3 TDMA MAC layer, with the proper scheduling and routing schemes can satisfactorily meet QoS requirements in the context of multi-hop networks. Multi-hop WPAN based on the OFDM UWB physical layer has been determined to be a viable approach to extend the network coverage while adequately supporting very high data rate multimedia traffic.