Distributed Power and Admission Control for Cognitive Radio Networks Using Antenna Arrays

Abstract

We consider a system where two networks, namely the primary and secondary network opearate by sharing a common radio spectrum that is licensed to the primary network. The secondary network uses cognitive radio technology to serve a number of secondary users, by making opportunistic access of the radio spectrum. For this system scenario, we present a distributed power and admission control algorithm with beamforming that minimizes the total transmitted power of the system such that the primary users as well as all secondary users who are permitted to be active in the system are guaranteed with their signal to interference plus noise ratio (SINR) requirements. Simulation results are provided to see the performance of the algorithm.

Optimal multiuser beamforming and power allocation for hierarchical cognitive radio systems

“…By solving (8), we can further check whether the chosen Ω (0) is feasible and the optimal value for R 1 Ω (0) exists. Once there is no feasible vector Ω (0) at the initialization, it means that the setting values I max , γ min,k , and P max for the three constraints in (6) are too strict to allow concurrent transmission for all secondary users. Choose a fixed step size for δ, and 0 < δ < 1.…”

“…We jointly design the beamforming weights and the allocated power for multiple users to maximize the sum rate of the underlying CR system, while ensuring that three main constraints, including interference power to the primary base station (PB), required SINR for the secondary users, and total transmission power from the secondary base station (SB), are satisfied. As compared with those works without adopting beamforming or merely concerning power control [6] - [9], it is cumbersome to find the optimal solution for jointly designing multiuser beamforming and power allocation through convex optimization because the objective function involved in the optimization problem is non-convex. The main contribution of this paper is to propose an iterative rate maximization (IRM) algorithm to solve the aforementioned optimization problem.…”

“…Some recent research works describing the underlying CR systems with antenna beamforming can be found in [6]- [8]. Two essential issues associated with allocating power and designing beamforming weights for the secondary users are investigated in these works to meet the different targets of sum rate maximization or transmission power minimization.…”

“…Two essential issues associated with allocating power and designing beamforming weights for the secondary users are investigated in these works to meet the different targets of sum rate maximization or transmission power minimization. In [6], an algorithm, which computes the power control values and the beamforming weights in turn, is proposed to minimize the total transmission power of the CR system and to satisfy the signalto-interference plus noise power ratio (SINR) requirement for both the primary and secondary users. In [7], the problem of joint power control and beamforming is studied to achieve the same goal, subject to the constraints that interference power to the primary user is below a threshold and SINR of the secondary users is above an acceptable value.…”

Joint Admission Control, Channel Assignment and QoS Routing for Coverage Optimization in Multi-Hop Cognitive Radio Cellular Networks

“…Most of work only focused on the single-channel scheme. Islam et al [7] investigated the distributed scheme in the CogCell with one BS equipped with multiple antennas, one primary transmitter (PT) and one primary receiver (PR). In [12] and [13], Xing et al proposed a distributed constrained power control algorithm under the consideration of the CogCell with one PR, and several SUs with separative secondary receivers, based on a game-theory approach.…”