Heterogeneous Wireless Ad Hoc Networks Research Articles

An EAOW algorithm to optimize the throughput in ad-hoc network in emergency communication environment

For improving the throughput of wireless ad-hoc networks in emergency communication environments, this paper proposes an enhanced adaptive on-demand weighted clustering algorithm. The clustering algorithm is very important in heterogeneous wireless ad-hoc networks, but the widely used AOW algorithm has certain limitations. Combined with the emergency communication environment, this article first analyzes the importance of clustering algorithm in improving network throughput, and secondly introduces and analyzes the two shortcomings of the AOW algorithm. On this basis, an enhanced adaptive on-demand weighted clustering algorithm (EAOW) is proposed. In the EAOW algorithm, each weight factor is dimensionlessly processed, and the properties of the nodes are added to the heterogeneous network. The simulation results show that compared with the AOW algorithm, the EAOW algorithm has an obvious progress in the number of cluster heads and the network throughput.

Design of Enhanced RTP-RTCP Protocols for Heterogeneous Wireless Ad-hoc Networks to Enhance Channel Coverage and Capacity

Design of Enhanced RTP-RTCP Protocols for Heterogeneous Wireless Ad-hoc Networks to Enhance Channel Coverage and Capacity

Maximal Independent Sets in Heterogeneous Wireless Ad Hoc Networks

In ad hoc wireless networks, a Connected Dominating Set (CDS) has been extensively used as a Virtual Backbone (VB) for routing. The majority of approximation algorithms for constructing a small CDS in wireless ad hoc networks follow a general two-phased approach. The first phase is to construct a Dominating Set (DS) and the second phase is to connect the nodes in it. Generally, in the first phase, a Maximum Independent Set (MIS) is used as the DS. The relation between the size of a Maximum Independent Set and a Minimum Connected Dominating Set (MCDS) plays the key role in the performance analyses of these two-phased algorithms. In homogeneous wireless ad hoc networks modeled as Unit Disk Graphs (UDG) and Unit Ball Graphs (UBG), the relation between them has been well studied. However, in heterogeneous wireless networks which generally modeled as Disk Graphs with Bidirectional links (DGB) and Ball Graphs with Bidirectional links (BGB), upper bounds for the size of MISs have seldom been studied. In this paper, we give tighter upper bounds for the size of MISs in heterogeneous wireless ad hoc networks. When the maximum and minimum transmission range are relatively close, our result is much better. In DGB, when the transmission range ratio is (1,1.152], (1.152,1.307], (1.307,1.407], (1.407,1.462], (1.462,1.515], (1.515,1.618], (1.618,1.932], we prove that the size of any Maximal Independent Set (MIS) is upper bounded by 6opt + 1, 7opt + 1, 8opt + 1, 9opt + 1, 10opt + 1, 11opt + 1, 16.7778opt + 1.2222, where opt denotes the size of an optimal solution of the CDS problem.

Error Control for Local Broadcasting in Heterogeneous Wireless Ad Hoc Networks

Local (single-hop) broadcasting is widely employed in distributed protocols (e.g., neighbor discovery, local information exchange in distributed network optimization and gossip-based algorithms) in wireless ad hoc networks. The performance of local broadcasting is characterized by the mean number of neighbors and the probability distribution of the number of neighbors of a broadcasting node. In this paper, we study the performance of local broadcasting in heterogeneous wireless ad hoc networks in which inter-system interference dominates signal reception quality, considering general fading distributions of both the desired signal and the interfering signals. In addition, we investigate the impacts of different error control techniques (e.g., simple retransmission, Chase combining, and incremental redundancy) on the performance of local broadcasting. The increase in the mean number of neighbors of a broadcasting node with respect to the number of retransmissions of a message is clarified, facilitating QoS provisioning in reliable local broadcasting in interference-limited heterogeneous wireless ad hoc networks.

Introduction to the Special Issue on Heterogeneous Wireless Ad Hoc and Sensor Networks

Introduction to the Special Issue on Heterogeneous Wireless Ad Hoc and Sensor Networks