Channel allocation schemes

About: Channel allocation schemes is a research topic. Over the lifetime, 10656 publications have been published within this topic receiving 182117 citations.

A prioritized handoff dynamic channel allocation strategy for PCS

Abstract: An analytical method is developed to calculate the blocking probability (p/sub b/), the probability of handoff failure (p/sub h/), the forced termination probability (p/sub ft/), and the probability that a call is not completed (p/sub nc/) for the no priority (NPS) and reserved channel (RCS) schemes for handoff, using fixed channel allocation (FCA) in a microcellular system. Based only on the knowledge of the new call arrival rate, a method of assessing the handoff arrival rate for any kind of traffic is derived. The analytical method is valid for uniform and nonuniform traffic distributions and is verified by computer simulations. An extension (generalization) to the nonuniform compact pattern allocation algorithm is presented as an application of this analysis. Based on this extended concept, a modified version of a dynamic channel allocation strategy (DCA) called compact pattern with maximized channel borrowing (CPMCB) is presented. With modifications, it is shown that CPMCB is a self-adaptive prioritized handoff DCA strategy with enhanced performance that can be exploited in a personal communications service (PCS) environment leading either to a reduction in infrastructure or to an increase in capacity and grade of service. The effect of user mobility on the grade of service is also considered using CPMCB.

Joint Channel Allocation, Interface Assignment and MAC Design for Multi-Channel Wireless Mesh Networks

Abstract: In a wireless mesh network (WMN) with a number of stationary wireless routers, the aggregate capacity can be increased when each router is equipped with multiple network interface cards (NICs) and each NIC within a router is assigned to a distinct orthogonal frequency channel. In this paper, given the logical topology of the network, we formulate the joint channel allocation, interface assignment, and media access control (MAC) problem as a cross-layer non-linear mixed-integer network utility maximization problem. An optimal joint design, based on exact binary linearization techniques, is proposed which leads to a global maximum. A near-optimal joint design, based on approximate dual decomposition techniques, is also proposed which is of more interest in terms of practical deployment. Performance evaluation is given through a number of numerical examples in terms of network utility maximization and aggregate network throughput.

Distributed cognitive coexistence of 802.15.4 with 802.11

Abstract: Thanks to recent advances in wireless technology, a broad range of standards are currently emerging. Interoperability and coexistence between these heterogeneous networks are becoming key issues, which require new adaptation strategies to avoid harmful interference. In this paper, we focus on the coexistence of 802.11 Wireless LAN and 802.15.4 sensor networks in the ISM band. Those networks have very different transmission characteristics that result in asymmetric interference patterns. We propose distributed adaptation strategies for 802.15.4 nodes, to minimize the impact of the 802.11 interference. This interference varies in time, frequency and space and the sensor nodes adapt by changing their frequency channel selection over time. Different distributed techniques are proposed, based on scanning (with increasing power cost) on the one hand, and based on increased cognition through learning on the other hand. These techniques are evaluated both for performance and energy cost. We show that it is possible to achieve distributed frequency allocation approaches that result only in an increase of 20% of the delay performance compared to ideal frequency allocation. Moreover, it is shown that a factor of two in energy consumption can be saved by adding learning to the system.

OVSF code channel assignment for IMT-2000

Abstract: Code channel assignment deals with the problem that how different codes are allocated to different connections. In the 3GPP technical specifications, the channelization codes used for spreading are orthogonal variable spreading factor (OVSF) codes. It can preserve the orthogonality between user's physical channels. OVSF codes are valuable resources in CDMA systems and should be properly managed. The objective of this paper is to find a code channel assignment method to support as many users as possible with less complexity. We proposed a code channel assignment method for user equipment (UE) that has the capability to support multi-rate services using multi-code transmission. A single table is used to allocate codes to a UE according to its requested data rate. Therefore, the allocation and releasing procedures, which can be accomplished in a very short period of time, are efficient.

Dynamic channel allocation method and system for integrated services digital network

Abstract: Dynamic channel allocation in an ISDN line is implemented above a Level II link layer protocol (LAPD). The preferred embodiment comprises programming operating on a computing platform system including a communication coprocessor system. The programming includes a channel management module (CMM) and a virtual channel module (VCM) to implement dynamic channel Allocation. The modules cooperate to control bandwidth between communication partners by selective allocation and deallocation of virtual B-Channels between them in response to preassigned priorities and real time events. Voice and data channels are interrogated. Channel deallocation also takes place in response to high error rates in message transmission.