Stability of Rate and Power Control Algorithms in Wireless Cellular Networks

• In radio resource management for cellular networks a trade-off has to be made between the congestion level, related to cell coverage and intercell interference, and the Quality of Service (QoS) or data rates of the users. This is implemented by using a fast inner power control loop and an outer rate control algorithm, working on a slower time scale. Due to the distributed nature of the network, both information and control is distributed. Measurements of congestion and QoS are used in the control loops and this introduces a nonlinear feedback. Another complicating factor is that filtering, computations and information exchange in the network introduce time delays. In this paper we propose a general high order model as a cascade system with an outer and inner control loop. The control algorithms use distributed information available in the network. The full system model includes the nonlinear feedback from congestion and QoS measurements, time delays and time scale modelling. We provide sufficient conditions for stability and convergence of the system. Our primary analysis tool is input output theory.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Reglerteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Control Engineering (hsv//eng)

Nyckelord

Radio Systems

Framework

Publikations- och innehållstyp

ref (ämneskategori)

kon (ämneskategori)