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In this paper, a new technique for dynamic spectrum management of a Wideband Code Division Multiple Access (WCDMA)/Digital Video Broadcasting (DVB) heterogeneous system is introduced. The solution is obtained using coloring theory, and significantly reduces the complexity of spectrum management.

This paper discusses the joint session scheduling (JOSCH) problem for multimedia services in heterogeneous wireless networks. The adaptive JOSCH based on layer-encoded streaming is designed for real-time multimedia service simultaneously transmitted by several heterogeneous radio access technologies (RATs). Considering the layered characteristics of the layer-encoded streaming, an adaptive JOSCH mechanism, along with the supporting network architecture, is designed to make efficient usage of the heterogeneous wireless resources and adapt to the dynamic network changes. Simulation results show that the adaptive JOSCH is effective in guaranteeing the QoS of multimedia and maintaining a high transmitting adaptability in multi-RATs environment.

Low utilization efficiency of spectrum, which is caused by fixed spectrum allocation scheme, is the bottleneck of wireless communication systems. Cognitive Radio (CR) is proposed to utilize the idle spectrum in an intelligent way while not interfering with primary users. For application of CR, the objective is the optimization of spectrum utilization. In order to achieve this, we propose a multi-channel transmission scheme in CR Networks which is based on Layered Coding scheme. For ensuring QoS of secondary users, we assign the data with different priority to spectrum with different stability. The expectation-utility theory is used to evaluate the performance of the proposed scheme according to supposed spectrum occupation states. Compared with existing data transmission schemes, the proposed scheme not only brings better satisfaction of users but also improves the spectrum utilization.

This paper brings forward a microeconomics based radio resource allocation (MBRRA) scheme to solve the joint radio resource management (JRRM) problem in the beyond 3G (B3G) heterogeneous wireless networks. The MBRRA mechanism is formulated based on game theory. Through the resource allocation game played by different operators, the radio resource is utilized effectively. Simulation results show that the proposed scheme effectively improves the operators' profit and the radio resource utilization efficiency. Besides, the game converges quickly to the Nash equilibrium, and achieves a well balance of high degree of efficiency and fairness at the equilibrium.

A utility based centralized self-configuration algorithm (UCSCA) is proposed to improve global quality of service (QoS) performance in heterogeneous radio network. The radio access technology (RAT) limitation, together with the base stations restrictions, makes it difficult to achieve a high-performance network reconfiguration solution (base stations load-allocation and terminal access schemes) in heterogeneous radio network The UCSCA's self-configuration solution, which takes account of cognized network environments factors such as terminal distribution, QoS demand, and base station capacity, is obtained by using the utility-based mixed strategy. The simulation result shows that the overall network utility performance, in terms of low blocking probability and high QoS satisfying, is significantly improved by using UCSCA's self-configuration solution.

The scarcity of spectrum resource in future wireless networks has inspired the demand of dynamic spectrum management (DSM). This paper investigates a cell based dynamic spectrum management (CBDSM) scheme to enhance the spectrum utilization and maximize the profit of operators for cognitive networks. In this scheme, the economic factor of the spectrum is taken into account in order to guarantee the rationality for spectrum trading. Especially, we focus on the interference mitigation method, which is considered as a fundamental issue for applying DSM to wireless systems. As a potential tool for promoting the distributed autonomous radio resource optimization algorithms, game theory is applied in the DSM scheme to investigate a win-win solution for spectrum trading between RATs. The simulation results reveal that the proposed CBDSM scheme improves the spectrum utilization and the profit of operators while effectively mitigating mutual interference between wireless networks.

This article proposes an auction mechanism based scheme for joint radio resource management (JRRM) in a reconfigurable system in a multi-operator scenario. Through the periodical auction and transaction for the radio resource between different radio access technologies (RATs) of multiple operators, the spare radio resource can be fully utilized to meet the demand of the RATs being short of radio resource. In order to rationally handle the profit assignment between multiple operators, a specific pricing strategy is put forward. In addition, a novel architecture is also presented to support this JRRM scheme. Simulation results reveal that the proposed scheme not only effectively reduces the total session blocking probability, but also greatly improves the total radio resource utilization ratio and the profits of operators.

Future wireless systems are characterized by the pouring of diversified services supported by heterogeneous radio access technologies (RATs). In parallel with this, the tremendous demand for spectrum has brought the requirement of dynamic spectrum allocation (DSA) into our sight. This article aims at designing a centralized DSA scheme to enhance the spectrum utilization and maximize the profit of operators for cooperative wireless networks. In this scheme, the economic factor of the spectrum of wireless systems is considered in order to guarantee the fairness for the spectrum allocation. RATs are considered as cooperative players participating in cooperative games for spectrum allocation. As an attractive solution for n-person cooperative game with transferable utility, the Shapley value is adopted to handle the profit allocation among RATs. Particularly, we focus on the interference mitigation method, which is a fundamental issue for applying DSA to real wireless systems. The simulation results reveal that the proposed DSA scheme not only improves the spectrum utilization and the profit of operators, but also effectively restrains the inter-system interference between wireless networks under an acceptable level.