A framework for development and evaluation of a dynamic subchannel allocation scheme in an OFDMA system
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This paper presents a framework for allocating radio resources to the Access Points (APs) introducing an Access Point Controller (APC). Radio resources can be either time slots or subchannels. The APC assigns subchannels to the APs using a dynamic subchannel allocation scheme. The developed framework evaluates the dynamic subchannel allocation scheme for a downlink multicellular Orthogonal Frequency Division Multiple Access (OFDMA) system. In the considered system, each AP and the associated Mobile Terminals (MTs) are not operating on a frequency channel with fixed bandwidth, rather the channel bandwidth for each AP is dynamically adapted according to the traffic load. The subchannels assignment procedure is based on quality estimations due to the interference measurements and the current traffic load. The traffic load estimation is realized with the measurement of the utilization of the assigned radio resources. The reuse partitioning for the radio resources is done by estimating mutual Signal to Interference Ratio (SIR) of the APs. The developed dynamic subchannel allocation ensures Quality of Service (QoS), better traffic adaptability, and higher spectrum efficiency with less computational complexity.
KeywordsAccess point controller OFDMA system Frequency reuse Hierarchical radio resource management Decision functions Dynamic subchannel allocation
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- 3.Choi M, Hanzo BJ, Munster L, Keller T (2003) OFDM and MC-CDMA for broad- band multi-user communications, WLANs and broadcasting. Wiley, United Kingdom Google Scholar
- 4.Einhaus M, Klein O (2006) The effects of time and frequency domain resource partitioning in OFDMA systems. In Proceedings of 12th European wireless conference Google Scholar
- 6.Furukawa H, Akaiwa Y (1993) Self organized reuse partitioning, dynamic channel assignment method in cellular systems. In Proceedings of the 43rd IEEE VTC, pp 524–527 Google Scholar
- 8.Kim I, Lee H (2001) On the use of linear programming for dynamic subchannel and bit allocation in multiuser OFDM. IEEE Glob Telecommun Conf 6:3648–3652 Google Scholar
- 11.Li G, Liu H (2003) Downlink dynamic resource allocation for multicell OFDMA system. In Proceedings of the 38th Asilomar conference signals, systems, and computers, pp 517–521 Google Scholar
- 13.Org CG, Schreiber F (1996) The RESTART/LRE method for rare event simulation. In Proceedings of the winter simulation conference, pp 390–400 Google Scholar
- 14.Pietrzyk S, Janssen G (2002) Multiuser subcarrier allocation for QoS provision in OFDMA systems. Proc VTC 2:1077–1081 Google Scholar
- 15.Tuerke U (2000) Centralized dynamic channel allocation in HiperLAN/2. Diploma thesis, RWTH Aachen University, Aachen, Germany Google Scholar
- 16.Roy B (2005) Dynamic subchannel allocation in a multi-cellular OFDMA system based on interference measurement and traffic situation. Master thesis, RWTH Aachen University, Aachen, Germany Google Scholar
- 17.Yin H, Liu H (2000) An efficient multiuser loading algorithm for OFDM-based broadband wireless systems. IEEE Glob Telecommun Conf 1:103–107 Google Scholar
- 18.Rappaport T (2002) Wireless communications principles and practices. Prentice Hall PTR, United States of America Google Scholar