6 research outputs found
Multipath effect on the WCDMA uplink capacity of highways cigar-shaped microcells with users within cars and buses
The final publication is available at Springer via http://dx.doi.org/10.1007/s11277-012-0900-3In this work, the effect of the multipath on the capacity and the interference statistics of the sectors of the highways cigar-shaped W-CDMA microcells is studied. A model of five microcells is used to analyze the uplink. The capacity and the interference statistics of the microcell are studied for different antenna sidelobe levels and different sector ranges. In the study, imperfect power control and limited transmitted power are assumed. Users are assumed to be within equally spaced buses and cars. The uplink capacity of the sector is studied assuming three types of services, namely, voice, 3G data and 3.75G data (representing the High Speed Uplink Packet Access). It is shown that, the sector uplink capacity depends on the buses and cars density within the sector. The capacity is also given as a function of the number of buses and cars within the sector
WCDMA Uplink Capacity of a Long Tunnel Cigar-shaped Microcells for Underground Train Service
In this paper, the capacity and the interference statistics of the sectors of the cigar-shaped WCDMA microcells are studied using the hybrid model of propagation. A model of nine microcells in a metro tunnel is used to analyze the uplink capacity and the interference statistics. The capacity and the interference statistics of the microcells in metro tunnels are studied in this work for different propagation parameters, antenna side lobe levels, sector ranges and bends losses
Energy Efficiency in Hybrid Mobile and Wireless Networks
Wireless Internet access is almost pervasive nowadays, and many types of wireless
networks can be used to access the Internet. However, along with this growth,
there is an even greater concern about the energy consumption and efficiency of mobile
devices as well as of the supporting networks, triggering the appearance of the
concept of green communication. While some efforts have been made towards this
direction, challenges still exist and need to be tackled from diverse perspectives.
Cellular networks, WLANs, and ad hoc networks in the form of wireless mesh
networks are the most popular technologies for wireless Internet access. The availability
of such a variety of access networks has also paved the way to explore synergistic
approaches for Internet access, leading to the concept of hybrid networks
and relay communications. In addition, many mobile devices are being equipped
with multiple interfaces, enabling them to operate in hybrid networks. In contrast,
the improvements in the battery technology itself have not matched the pace of the
emerging mobile applications. The situation becomes more sophisticated when a
mobile device functions also as a relay node to forward other station’s data. In the
literature, energy efficiency of mobile devices has been addressed from various perspectives
such as protocol-level efforts, battery management efforts, etc. However,
there is little work on energy efficiency in hybrid mobile and wireless networks
and devices with heterogeneous connections. For example, when there are multiple
networks available to a mobile device, how to achieve optimum long-term energy
consumption of such a device is an open question.
Furthermore, in today’s cellular networks, micro-, pico-, and femto-cells are the
most popular network topologies in order to support high data rate services and
high user density. With the growth of such small-cell solutions, the energy consumption
of these networks is also becoming an important concern for operators.
Towards this direction, various solutions have been proposed, ranging from deployment
strategies for base stations to cooperative techniques etc. However, as base
stations have the largest share in a network’s energy consumption, methods that allow
lightly-loaded base stations sleep or be switched off are possible means as a
feasible step towards green communications.
In this dissertation, we tackle the above mentioned problems from two perspectives,
i.e., mobile station’s and operator’s perspectives. More specifically, by taking
into account the amount of transferred data in uplinks and downlinks individually
for various components in a hybrid network, strategies are proposed to reduce mobile
station’s battery energy consumption. For this purpose, other parameters such as link distance and remaining battery energy can also be considered for handover
decision making, in order to maximize energy efficiency of the mobile station. To
optimize long-term energy consumption of the mobile stations operated in such
scenarios, a Markov decision process-based methodology is proposed as our contribution
to this topic. Moreover, from operator’s perspective, a network energy
conservation scheme which may switch off a base station is proposed for micro- or
pico-cells scenarios. Both deterministic and probabilistic schemes are proposed for
network energy conservation. The problems considered and the solutions proposed
in this dissertation advance the frontiers of the research work within the theme of energy
efficiency for mobile devices as well as hybrid mobile and wireless networks
Advanced Trends in Wireless Communications
Physical limitations on wireless communication channels impose huge challenges to reliable communication. Bandwidth limitations, propagation loss, noise and interference make the wireless channel a narrow pipe that does not readily accommodate rapid flow of data. Thus, researches aim to design systems that are suitable to operate in such channels, in order to have high performance quality of service. Also, the mobility of the communication systems requires further investigations to reduce the complexity and the power consumption of the receiver. This book aims to provide highlights of the current research in the field of wireless communications. The subjects discussed are very valuable to communication researchers rather than researchers in the wireless related areas. The book chapters cover a wide range of wireless communication topics
Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress
Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018
Understanding Quantum Technologies 2022
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October 2021.Comment: 1132 pages, 920 figures, Letter forma