Abstract
Pilot power management is an important issue for efficient resource utilization in WCDMA networks. In this paper, we consider the problem of minimizing pilot power subject to a coverage constraint. The constraint can be used to model various levels of coverage requirement, among which full coverage is a special case. The pilot power minimization problem is \({{\cal N}{\cal P}}\)-hard, as it generalizes the set covering problem. Our solution approach for this problem consists of mathematical programming models and methods. We present a linear-integer mathematical formulation for the problem. To solve the problem for large-scale networks, we propose a column generation method embedded into an iterative rounding procedure. We apply the proposed method to a range of test networks originated from realistic network planning scenarios, and compare the results to those obtained by two ad hoc approaches. The numerical experiments show that our algorithm is able to find near-optimal solutions with a reasonable amount of computing effort for large networks. Moreover, optimized pilot power considerably outperforms the ad hoc approaches, demonstrating that efficient pilot power management is an important component of radio resource optimization. As another part of our numerical study, we examine the trade-off between service coverage and pilot power consumption.
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References
3GPP, Technical Specification 25.133, Requirements for Support of Radio Resource Management (FDD), V 7.2.0 (December 2005).
3GPP, Technical Specification 25.211, Physical Channels and Mapping of Transport Channels onto Physical Channels (FDD), V 7.0.0 (March 2006).
3GPP, Technical Specification 25.331, Radio Resource Control (RRC); Protocol Specification, V 7.0.0 (March 2006).
ILOG, Ilog CPLEX, User’s Manual (August 2000).
Momentum Data, http://momentum.zib.de/data.php (last update in November 2005).
A. Eisenblätter, T. Koch, A. Martin, T. Achterberg, A. Fügenschuh, A. Koster, O. Wegel and R. Wessäly, Modelling feasible network configurations for UMTS, in Telecommunications Network Design and Management, G. Anandalingam and S. Raghavan, Eds.: Kluwer Academic Publishers (2002).
H. Holma and A. Toskala (Eds.) WCDMA for UMTS : Radio Access for Third Generation Mobile Communications (3rd ed.) John Wiley & Sons, Chichester, UK (2004).
D. Kim, Y. Chang and J. W. Lee, Pilot power control and service coverage support in CDMA mobile systems, in Proc. of the 49th IEEE Vehicular Technology Conference (May 1999) pp. 1464–1468.
J. Laiho, A. Wacker and T. Novasad (Eds.) Radio Network Planning and Optimisation for UMTS, John Wiley & Sons (2002).
R. T. Love, K. A. Beshir, D. Schaeffer and R. S. Nikides, A pilot optimization technique for CDMA cellular systems, in Proc. of the 49th IEEE Vehicular Technology Conference (May 1999) pp. 2238–2242.
I. Siomina and D. Yuan, Pilot Power Optimization in WCDMA Networks, in Proc. of the 2nd Workshop on Modelling and Optimization in Mobile, Ad Hoc and Wireless Networks, (March 2004) pp. 191–199.
Y. Sun, F. Gunnarsson and K. Hiltunen, CPICH power settings in irregular WCDMA macro cellular networks, in Proc. of IEEE Personal, Indoor and Mobile Radio Communications (September 2003) pp. 1176–1180.
K. Valkealahti, A. Höglund, J. Pakkinen and A. Flanagan, WCDMA common pilot power control with cost function minimization, in Proc. of the 56th IEEE Vehicular Technology Conference (September 2002) pp. 2244–2247.
P. Värbrand and D. Yuan, A mathematical programming approach for pilot power optimization in WCDMA networks, in Proc. of 2003 Australian Telecommunications Networks and Applications Conference (December 2003).
J. Yang and J. Lin, Optimization of pilot power management in a CDMA radio network, in Proc. of the 52nd IEEE Vehicular Technology Conference (September 2000) pp. 2642–2647.
H. Zhu, T. Buot, R. Nagaike and S. Harman, Load balancing in WCDMA systems by adjusting pilot power, in Proc. of the 5th International Symposium on Wireless Personal Multimedia Communications (October 2002) pp. 936–940.
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Iana Siomina received her MSc degree in Scientific Computing from the Royal Institute of Technology, Sweden, in 2002. In 2004, she received her MSc in Computer and System Sciences from the Stockholm University, Sweden. Currently, she is working towards her PhD degree in Infrainformatics with emphasis on applied system optimization for wireless networks at the Department of Science and Technology, Linköping University, Sweden. Her main research interests include planning, dimensioning, and radio network optimization for UMTS networks and WLANs, efficient broadcast communication in wireless ad hoc networks, and wireless network simulation.
Di Yuan received his MSc degree in Computer Science and Engineering, and PhD degree in Operations Research at Linköping Institute of Technology, Sweden, in 1996 and 2001, respectively. At present he is associate professor in Telecommunications at the Department of Science and Technology, Linköping University, Sweden. His research interests span over design, analysis, and resource optimization of telecommunication systems. He has authored or co-authored over 30 refereed articles in international journals and conference proceedings. His current research addresses network design and bandwidth allocation in UMTS systems, and resource management in ad hoc networks.
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Siomina, I., Yuan, D. Minimum pilot power for service coverage in WCDMA networks. Wireless Netw 14, 393–402 (2008). https://doi.org/10.1007/s11276-006-0727-5
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DOI: https://doi.org/10.1007/s11276-006-0727-5