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Computer Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

2013

Computer and Systems Architecture

Hong-Ning Dai

Performance of Wireless Networks

Articles 1 - 3 of 3

Full-Text Articles in Computer Engineering

Connectivity Of Wireless Ad Hoc Networks: Impacts Of Antenna Models, Qiu Wang, Hong-Ning Dai, Qinglin Zhao Dec 2012

Connectivity Of Wireless Ad Hoc Networks: Impacts Of Antenna Models, Qiu Wang, Hong-Ning Dai, Qinglin Zhao

Hong-Ning Dai

This paper concerns the impact of various antenna models on the network connectivity of wireless ad hoc networks. Existing antenna models have their pros and cons in the accuracy reflecting realistic antennas and the computational complexity. We therefore propose a new directional antenna model called Approx-real to balance the accuracy against the complexity. We then run extensive simulations to compare the existing models and the Approx-real model in terms of the network connectivity. The study results show that the Approx-real model can better approximate the best accurate existing antenna models than other simplified antenna models, while introducing no high computational …


An Overview Of Using Directional Antennas In Wireless Networks, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2012

An Overview Of Using Directional Antennas In Wireless Networks, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

Compared with omni-directional antennas, directional antennas have many merits, such as lower interference, better spatial reuse, longer transmission range and the improved network capacity. Directional antennas enable numerous emerging outdoor and indoor applications, which have been addressed in many recent studies. Despite the advances in wireless networks with directional antennas (DAWNs), there are many research challenges in all layers of DAWNs. This paper presents a detailed study on recent advances and open research issues on DAWNs. Firstly, we briefly introduce the classification of directional antennas, antenna radiation patterns, antenna modes as well as the challenges in the physical layer of …


Channel Allocation In Wireless Networks With Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2012

Channel Allocation In Wireless Networks With Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

In this paper, we study the channel allocation in multi-channel wireless ad hoc networks with directional antennas. In particular, we investigate the problem: given a set of wireless nodes equipped with directional antennas, how many channels are needed to ensure collision-free communications? We derive the upper bounds on the number of channels, which heavily depend on the node density and the interference ratio (i.e., the ratio of the interference range to the transmission range). We construct several scenarios to examine the tightness of the derived bounds. We also take the side-lobes and back-lobes as well as the signal path loss …