Service driven dynamic hashing based radio resource management for intelligent transport systems

Abstract

Intelligent Transport Systems (ITS) aim to improve transport safety, productivity and reliability by interconnecting different transport entities and providing real-time instantaneous transport information to various transport system users. Communication systems play an important role in achieving this mission. Heterogeneous technologies/protocols such as WLAN, DSRC, RFID, GSM, WiMAX etc. currently constitute the communication system of ITS. ITS comprises of various services (monitoring, navigation, value-added services etc.) with diverse Quality of Service (QoS), latency & throughput requirements. Large number of aperiodic and sporadic service requests from heterogeneous radio communication devices are expected to result in another type of congestion; the spectral congestion. In this paper, we propose an efficient radio resource management scheme using Complex Event Processing (CEP) based Service-Prioritized Opportunistic Communication (SPOC) architecture to address this spectral congestion. Based on CEP, SPOC processes the simple events such as information about spectrum usage patterns, radio device abilities, geo-locations, spectrum needs and derives complex spectrum allocation decisions. Spectrum allocation and management decisions are governed by policy engine of SPOC. Volume of spectrum request is predicted by Time of the Day based Dynamic Hashing algorithm that reduces computation complexities and achieves faster spectrum allocation decision. This infrastructure based spectrum management technique is shown to improve service completion rate for all devices while satisfying dynamic QoS needs of emergency/high priority services of ITS. Compared to existing scheduling schemes such as Greedy, Max-Min and Early Dead-Line First algorithms, SPOC is shown to be more suitable for ITS paradigm due to its ability to coordinate several hundreds of spectrum demands in real-time, while maintaining fairness.