Evaluation of Dynamic Channel and Power Assignment for Cognitive Networks

Power Control and Scheduling For Low SNR Region in the Uplink of Two Cell Networks

In this paper we investigate the sub-channel assignment and power control to maximize the total sum rate in the uplink of two-cell network. It is assumed that there are some sub-channels in each cell which should be allocated among some users. Also, each user is subjected to a power constraint. The underlying problem is a non-convex mixed integer non-linear optimization problem which does not h...

Evaluation of Dynamic Channel and Power Assignment Techniques for Cognitive Dynamic Spectrum Access Networks

Spectrum Assignment in Cognitive Radio Networks Using Fuzzy Logic Empowered Ants

The prevalent communications networks suffer from lack of spectrum and spectrum inefficiency. This has motivated researchers to develop cognitive radio (CR) as a smart and dynamic radio access promised solution. A major challenge to this new technology is how to make fair assignment of available spectrum to unlicensed users, particularly for smart grids communication. This paper introduces an i...

Editorial: Special Issue on Cognitive Radio Networks and Communications

Cognitive radio networks and communications is an emergent paradigm to address the spectrum scarcity challenge in the wireless community. Currently, different wireless systems are regulated by a fixed spectrum assignment strategy. This policy partitions the whole spectrum into a large number of different ranges. Each piece is exclusively used by a specific wireless system. This leads to an unde...

Adaptive Subcarrier Assignment and Power Distribution in Multiuser OFDM Systems with Proportional Data Rate Requirement

A low complexity dynamic subcarrier and power allocation methodology for downlink communication in an OFDM-based multiuser environment is developed. The problem of maximizing overall capacity with constraints on total power consumption, bit error rate and data rate proportionality among users requiring different QOS specifications is formulated. Assuming perfect knowledge of the instantaneo...

A Novel Multicast Tree Construction Algorithm for Multi-Radio Multi-Channel Wireless Mesh Networks

Many appealing multicast services such as on-demand TV, teleconference, online games and etc. can benefit from high available bandwidth in multi-radio multi-channel wireless mesh networks. When multiple simultaneous transmissions use a similar channel to transmit data packets, network performance degrades to a large extant. Designing a good multicast tree to route data packets could enhance the...