Subcarrier and Power Allocation in OFDM-based Cognitive Radio Systems

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Author(s)

Pei Zhang 1,2,* Longxiang Yang 1,2 Xu Liu 1,2

1. Wireless Communications Key Lab of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, P. R. China, 210003

2. Wideband Wireless Communications and Sensor Networks Technology Lab, Ministry of Education of China, Nanjing, Jiangsu, P. R. China, 210013

* Corresponding author.

DOI: https://doi.org/10.5815/ijcnis.2010.01.04

Received: 2 Apr. 2010 / Revised: 13 Jun. 2010 / Accepted: 25 Aug. 2010 / Published: 8 Nov. 2010

Index Terms

Cognitive radio, OFDM, subcarrier allocation, power allocation

Abstract

For CR systems, where primary and CR users co-exist in adjacent bands, it is important to keep the interference introduced to the primary user (PU) band within a tolerable range. In this paper, we investigate the subcarrier and power allocation problem in CR systems, where primary and CR users co-exist in adjacent bands, while keeping the total interference introduced to the PU band below a certain threshold and the total power allocated to the CR users under a constraint. First, according to the different purposes of the resource allocation, several suboptimal subcarrier allocation algorithms are investigated, which are termed as Max-Rate, Min-Interference and Fair-Rate subcarrier allocation algorithm, separately. Further, for a given subcarrier allocation three suboptimal power allocation algorithms which have less complexity are proposed and compared to the optimal power allocation algorithm. Numerical results are obtained for the behaviors and performance of our proposed algorithms.

Cite This Paper

Pei Zhang, Longxiang Yang, Xu Liu, "Subcarrier and Power Allocation in OFDM-based Cognitive Radio Systems", International Journal of Computer Network and Information Security(IJCNIS), vol.2, no.1, pp.24-30, 2010. DOI:10.5815/ijcnis.2010.01.04

Reference

[1] S.Haykin, “Cognitive radio:brain-empowered wireless communications,” Selected Areas in Communications,IEEE Journal on,vol.23,pp.201–220, Feb.2005.

[2] T.Weiss,and F.K.Jondral,“Spectrum pooling: an innovative strategy for the enhancement of spectrum efficiency,”IEEE Commun.Mag.,vol.43,no.3,pp.S8-S14,Mar.2004.

[3] Z. Shen, J. G. Andrews, and B. L. Evans, “ Adaptive resource allocation in multiuser OFDM systems with proportional rate constraints”, in IEEE Trans. on Wireless Commun., vol. 4, No. 6, pp. 2726-2737, Nov. 2005.

[4] Feng-Seng Chu, Kwang-Cheng Chen, “Radio Resource Allocation in OFDMA Cognitive Radio Systems” Personal, Indoor and Mobile Radio Communications, 2007. IEEE 18th International Symposium on Digital Object Identifier: 10.1109/PIMRC.2007.4394507, Page(s): 1 – 5,2007.

[5] Sami M. Almalfouh, Gordon L. Stüber, “Interference Aware Subcarrier and Power Alloc ation in OFDMA-Based Cognitive Radio Networks”, Lecture Notes in Electrical Engineering, 1, Volume 41, Multi-Carrier Systems & Solutions 2009, I, Pages 35-45.

[6] G. Bansal, Md. J. Hossain, and V. K. Bhargava, “ Optimal and suboptimal power allocation schemes for OFDM-based cognitive radio systems, ” in IEEE Trans. on Wireless Commun., vol. 7, No. 11, pp. 4710-4718, Nov. 2008.

[7] G. Bansal, Md. J. Hossain, and V. K. Bhargava, “Subcarrier and power adaptation for multiuser OFDM-based cognitive radio systems”, Communications (NCC), 2010 National Conference on Digital Object Identifier: 10.1109/NCC.2010.5430230 Publication Year: 2010 , Page(s): 1 - 5

[8] Lun Tang, Huan Wang, Qianbin Chen, Guangming Liu, “Subcarrier and power allocation for OFDM-based cognitive radio networks”, Communications Technology and Applications, 2009. ICCTA '09. IEEE International Conference on Digital Object Identifier: 10.1109/ICCOMTA.2009.5349158 Publication Year: 2009 , Page(s): 457 – 461

[9] T.Weiss, J.Hillenbrand, A.Krohn, and F.K.Jondral, “Mutual interference in OFDM-based spectrum pooling systems,” in Proc. IEEE Vehicular Technol. Conf. (VTC’04), vol.4, pp.1873-1877, May 2004

[10] RHEE W. CIOFFI J M. “Increase in capacity of multiuser OFDM system using dynamic subchannel allocation” [C]. IEEE.Proceedings of IEEE Internationsl Vehicular Technology conference. Tokyo; IEEE, 2000: 1085-1089.