Optimal resource management in wireless multimedia wideband CDMA systems

Abstract

This paper proposes a scheme of optimal resource management for reverse-link transmissions in multimedia wideband code-division multiple-access (WCDMA) communications. It is to guarantee quality-of-service (QoS) by resource (transmit power and rate) allocation and to achieve high spectral efficiency by base-station assignment. This approach takes the form of a nonlinearprogramming large-scale optimization problem: maximizing an abstraction for the profit of a service provider subject to QoS satisfaction. Solutions for both single-cell and multicell systems are investigated. The single-cell solution has the advantage of low complexity and global convergence in comparison with the previous work. Maximum achievable throughput (capacity) of a single cell is mathematically evaluated and used as the benchmark for performance measure of multicell systems. For multicell systems, due to its max-max structure, solving the optimization problem directly entails a high-computational complexity. Instead, the problem is reformulated to a mixed integer nonlinear-programming (MINLP) problem. Then, binary variables indicating base-station assignments are relaxed to their continuous analogs to make a computer solution feasible. Furthermore, approximations can be made to make the resource-management scheme less computationally complex and allow its partial decentralization. The sensitivity of the proposed scheme to path-gain estimation error is studied. Simulation results are presented to demonstrate the performance of the proposed scheme and the throughput improvement achieved by combining resource allocation with base station assignment.Index Terms-Wideband code-division multiple access (WCDMA), resource management, quality of service (QoS), base station assignment, multimedia services.

Quality-of-service provisioning and efficient resource utilization in CDMA cellular communications

“…Therefore, it is desired if some MSs in the overloaded cell are handed over to the neighboring cell. That is, the BS assignment should be combined with power and rate allocation, taking into account of traffic load levels in the cells [64]. When highly bursty traffic such as high-rate data is considered, the possibility of the load asymmetry among cells increases.…”

“…When highly bursty traffic such as high-rate data is considered, the possibility of the load asymmetry among cells increases. Under this context, the system capacity can be better utilized if dynamic BS assignment is incorporated into the intercell coordination [19], [53], [64] at the cost of more computation complexity and signaling overhead.…”

On Maintaining Multimedia Session's Quality in CDMA Cellular Networks Using a Rate Adaptive Framework

“…Current standardization efforts of such services by major partnership projects (e.g., 3GPP and 3GPP2) have addressed the basic functional characteristics and requirements of the streaming services class for 3G CDMA-based networks (e.g., CDMA 2000 and W-CDMA) [6]. In such CDMA-based architectures, however, multiple access interference (MAI) plays a major role in resource management that is known to further complicate the designs (see, e.g., [1,3,7,8,9,13] and the references therein). Our focus in this paper is on designing call admission control (CAC), and adaptive bandwidth allocation (ABA) schemes that can be used to give assurance that the admitted streaming connections will continue receiving acceptable levels of service (e.g., a minimum acceptable data rate) over the duration of a complete streaming session (e.g., a few minutes long), and also during both intra-cell and inter-cell user movements.…”

QoS-oriented packet scheduling for wireless multimedia CDMA communications

“…If the received power is kept at the same level for all the traffic classes, the capacity is limited by the most stringent BER requirement and cannot be used efficiently. Recently, several approaches have been proposed for optimal power control for multimedia traffic to maximize the capacity or to minimize the total transmit power [2], [3], [4].…”