Optimal call admission control with QoS guarantee in a voice/data integrated cellular network

Abstract

Abstmet-This paper addresses the issue of call admission control with the necesary QaS guarantee for a micddala integrated wireless cellular network. Specifically, we propose a new call admission control policy called Dual-Threshold Call Admission Conml (DT-CAC) policy. It uses hw rhresholdr, one to reserve channels for narrow-band voice handoffcalls, and the other for wideband data handoff Irffic. Its unique features am: 1) it adopts the Complete Sharing (CS) approach that maximizes the channel emciency; 2) it derives the o p I h " se1 of thresholds that satisfies the QoS target on handoff dropping probabilities for both voice and data traffic, while at the same time minimizing the maximal new call hlwkining probability (voice or data). IQ performance is well supported by simulation results. I. INTRODUCTlONThere has been a rapid development in wireless cellular communications. The next generation of networks are expected to eventually carry multimedia traffic. One of the key issues is to ensure that the QoS requirement of the different applications are guaranteed. This paper addresses the call admission control for a voiddata integrated wireless cellular network. One of the key design goals is to limit the handoff dropping probability below a certain constraint. While cell sizes are systematically decreased to enable better frequency reuse, this also considerably increases the number of handoffs during a mobile's life time. Therefore, it becomes increasingly critical in micro or pico-cell wireless networks to have mechanisms that meet the following two challenges. First, they must maintain the handoff dropping probability at pre-specified target QoS levels. Second, in view of the increasing popularity of data services from simple short messages to GPRS, the networks must satisfy the different QoS requirements of all types of traffic.The Guard Channel (GC) based policies have been extensively studied in the traditional voice-centric cellular networks [4], (91. Its extension, the Fractional Guarded Channel (FCC) policy, is optimal for minimizing the call blocking probability subject to a hard constraint on the call dropping probability 181. For networks accommodating both narrow-band and narrow-band calls can request handoffs. Haung et al considered a voiceldata integrated system with finite buffers [SI, but the boundary for channel separation is "movable" according to traffic condition.To the best of our knowledge, there have been little studies addressing the QoS guarantee for multiple traffic types, which is the objective in this paper. Specifically, we propose a new call admission control policy called Dual-Threshold Call Admission Control (DT-CAC) policy, whose objective is to minimize the maximal new call blocking probability (voice or data) while satisfying the hard constraints on handoff dropping probabilities for both voice and data traffic.In order to maximize channel utilization, we adopt the CS approach, rather than the CP approach (21, [7]. The CP approach divides the available channels into separate...

Bandwidth Reallocation for Bandwidth Asymmetry Wireless Networks Based on Distributed Multiservice Admission Control

“…However, they did not investigate how many channels should be increased or decreased to satisfy different QoS requirements of diverse call classes. Chau et al extended the LFGC scheme to incorporate the multiple traffic classes in [20]. Simulated annealing technique is employed to obtain the optimal control parameters.…”

Delay Sensitive Communications over Cognitive Radio Networks

“…Admission control is critical for supporting QoS when there are too many users that want to access the network simultaneously. In traditional cellular networks, many results have shown that the optimal admission control policy has a threshold structure (e.g., [6]- [8]). In cognitive radio networks, researchers have studied admission control for both underlay networks (e.g., [9]- [11]) and overlay networks (e.g., [12], [13]).…”

Model for Call Acceptance Based on Handoff Guarantees for Two Classes of Users

“…Predictive schemes suffer either from approximation of number of handoff arrivals in a cell as normal [1] or Poisson [2] distribution or from complex tracking of the mobility of users [3]. On the other hand, in static schemes [4], [5], the numbers of different classes of calls in a cell are considered for accepting a new call in that cell. In static schemes, a cell is studied to approximate the whole cellular network and these schemes suffer from the approximation of handoff arrival process as Poisson process for exponentially distributed call holding duration and cell residence time.…”