Open Access
Power Control in Cellular Radio Systems : Analysis and Design
TLDR
In this work, analysis methods based on root locus and describing functions are discussed and the relevance of the methods is further illuminated by simulations.Abstract:
Many algorithms in communications systems can be considered as control loops, where the computed quantities depend on feedback information. A common scheme is to use increase/decrease signaling for bandwidth efficiency. Furthermore, the feedback information is delayed. The time delay itself, and even more pronounced in combination with nonlinearities, such as the increase/decrease mechanism, may cause oscillations and instabilities in the system. In this work, analysis methods based on root locus and describing functions are discussed. Design and tuning of algorithms are employed using pole placement techniques. Particular examples include clock synchronization in ADSL modems, control of available bit rate in data networks and, as studied in this project, distributed implementation of power control in cellular radio systems. The relevance of the methods is further illuminated by simulations.read more
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References
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Journal ArticleDOI
A simple distributed autonomous power control algorithm and its convergence
Gerard J. Foschini,Z. Miljanic +1 more
TL;DR: For wireless cellular communication systems, one seeks a simple effective means of power control of signals associated with randomly dispersed users that are reusing a single channel in different cells, and the authors demonstrate exponentially fast convergence to these settings whenever power settings exist for which all users meet the rho requirement.
Journal ArticleDOI
Signal and interference statistics of a CDMA system with feedback power control. II
S. Ariyavisitakul,Li Fung Chang +1 more
TL;DR: A combination of discrete-event link simulation and analysis of the obtained SIR statistics is used to explore the previously little-known behavior of a CDMA system using SIR-based power control and to obtain performance estimates for such a system under various operating assumptions.
Journal ArticleDOI
Distributed power control in cellular radio systems
TL;DR: The authors tighten the mathematical arguments and apply this scheme to cellular systems and present numerical results which show that the above scheme has the potential to converge faster than the scheme proposed by J. Zander (see IEEE Transactions on Vehicular Technology, vol.41, no.3, August 1992) for high CIR values.
Proceedings ArticleDOI
Signal and interference statistics of a CDMA system with feedback power control
S. Ariyavisitakul,L.F. Chang +1 more
TL;DR: A feedback power control approach that allows power commands to be updated at a higher rate than the rate of multipath fading is investigated and it is shown that often-used analyses based on perfect average power control lead to optimistic capacity results.