TY - GEN
T1 - Performance enhancement of contention-based bandwidth request mechanism in IEEE 802.16 WiMAX networks
AU - Chou, Shih Fan
AU - Liu, Jen Hsi
AU - Chao, Hsi Lu
AU - Guo, Tzu Chi
AU - Liu, Chia Lung
AU - Tsai, Feng Jie
N1 - Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2010
Y1 - 2010
N2 - The IEEE 802.16 standard is a promising technology for 4G mobile networks. Though supporting versatile service classes, best effort (BE) service class is expected to dominate WiMAX networks, due to operational simplicity. One of bandwidth request mechanisms that subscriber stations (SS) can utilize to issue bandwidth requests (BW-REQ) for BE connections is contention-based random access. An SS starts a timer T16 when transmitting a BW-REQ. If getting a grant before timer expiration, the SS transmits data packets at the allocated time slots; otherwise it performs truncated binary exponential backoff process for BW-REQ retransmission. The default value of T16 is one frame time. However, T16 impacts on contention and request collision significantly. In the paper, we develop an analytical model for T16 timer setting. Besides, we derive analytical expressions for the average number of tries per BW-REQ and the average packet delay. We compare the theoretical results of fixed and adjustable timers. The results show that adjusting timer reduces both the number of collision and the average packet delay.
AB - The IEEE 802.16 standard is a promising technology for 4G mobile networks. Though supporting versatile service classes, best effort (BE) service class is expected to dominate WiMAX networks, due to operational simplicity. One of bandwidth request mechanisms that subscriber stations (SS) can utilize to issue bandwidth requests (BW-REQ) for BE connections is contention-based random access. An SS starts a timer T16 when transmitting a BW-REQ. If getting a grant before timer expiration, the SS transmits data packets at the allocated time slots; otherwise it performs truncated binary exponential backoff process for BW-REQ retransmission. The default value of T16 is one frame time. However, T16 impacts on contention and request collision significantly. In the paper, we develop an analytical model for T16 timer setting. Besides, we derive analytical expressions for the average number of tries per BW-REQ and the average packet delay. We compare the theoretical results of fixed and adjustable timers. The results show that adjusting timer reduces both the number of collision and the average packet delay.
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U2 - 10.1109/PIMRC.2010.5672025
DO - 10.1109/PIMRC.2010.5672025
M3 - Conference contribution
AN - SCOPUS:78751541417
SN - 9781424480166
T3 - IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC
SP - 1287
EP - 1292
BT - 2010 IEEE 21st International Symposium on Personal Indoor and Mobile Radio Communications, PIMRC 2010
T2 - 2010 IEEE 21st International Symposium on Personal Indoor and Mobile Radio Communications, PIMRC 2010
Y2 - 26 September 2010 through 30 September 2010
ER -