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In order to result the problem of low-power routing for wireless sensor networks, a data aggregation routing protocol with minimum transmission cost spanning tree was proposed, Data from sensor nodes was transmitted to the root node to sink node within the same sensor area. Data aggregation and transmission to the in-network sink along the shortest path is in accordance with principles of least energy...
In this paper, several multi-user multiple-input multiple-output (MU-MIMO) linear precoding schemes with both perfect and imperfect channel state information (CSI) for downlink transmission are proposed. Compared to nonlinear precoding schemes which need perfect CSI to achieve the channel capacity, we focus on systems which are restricted to use only linear precoding schemes due to complexity constraints...
GPS is widely used in vehicle location. But it has many restrictions in underground parking or built-up place. So, we proposed an dual-mode approach based on GPS and GPSOne. At first, we make researching on the dual-mode switch positioning technology, and then set the judging criteria. Finally, provide the method of switching by engineering mathematics. It provide a good way to solve the blind spot...
The packer switching service of the third-generation mobile communication network (3G) has provide a broader range of services, while wireless local area network (WLAN) has a faster speed in information transmission, thus making these two complementary functionally. However, with the improvement of technology and increasing of mobile users, it has a significant impact on network communication when...
Ubiquitous Network Society (UNS) is viewed as the next general Information and Communication Technology (ICT) development destination by many developed countries (regions). And many countries such as China are following the successful cases to develop UNS strategy. Firstly, the content, characteristics, and significance together with strategic framework of UNS in the developed countries (regions)...
With the development of expressway, the vehicle path recognition based on RFID is designed and an Electronic Toll Collection system of expressway will be implemented. It uses a passive RFID tag as carrier to identify Actual vehicle path in loop road. The ETC system will toll collection without parking, also census traffic flow and audit road maintenance fees. It is necessary to improve expressway...
Wireless sensor networks consist of various sensor nodes which operate in a memory, energy and bandwidth constrained environment. Target tracking is an important application in wireless sensor networks and in this paper we propose an energy aware target tracking (EATT) algorithm. Energy efficiency is obtained due to the novel concept of tracking being performed in a collaborative manner by different...
This paper analyzes the energy consuming characteristics of data acquisition in wireless sensor network node. The impaction of node's data acquisition subsystem design is addressed. Schemes to improve energy saving of data acquisition are presented with precondition of guaranteeing performance, which includes choosing and setting working parameters of sensors, setting working parameters of the DC/DC...
In this paper we develop a discrete and distributed optimization framework that maximizes the overall spectral efficiency of heterogeneous networks while ensuring a minimum fairness among users. We split the problem into two subproblems: the first one is handled by the users and consists in a transmission by each user of a minimum rate requirement to the base stations and the second is the resource...
We propose advanced compressive estimators of doubly dispersive channels within multicarrier communication systems (including classical OFDM systems). The performance of compressive channel estimation has been shown to be limited by leakage components impairing the channel's effective delay-Doppler sparsity. We demonstrate a group sparse structure of these leakage components and apply recently proposed...
The statistical properties of the capacity of narrowband double Hoyt fading channels are studied. Toward this end, analytical expressions for the probability density function (PDF) and cumulative distribution function (CDF) of the instantaneous channel capacity process are derived. Furthermore, for the characterization of the dynamical behavior of the time-varying channel capacity, expressions are...
In this paper, we deal with the time slot allocation in time-hopping ultra-wide band (TH-UWB) ad-hoc networks in order to maximize the total sum rate. This problem is known to be a discrete NP-hard optimization problem and hence cannot be solved with a computationally efficient algorithm. Moreover, the sum rate maximization often leads to starvation of links experiencing bad channel conditions. Our...
We consider cooperative relaying systems employing amplify-and-forward (AF) distributed space-time block codes (DSTBCs) in which only backward channel-state-information (CSI) is known at relays and destination. For such systems, we study the particular case where, in order to minimize overhead, each of N relays decide independently whether to join the cooperation with basis on the received signal...
Optimal power allocation for pure relay networks utilizing repetition codes has drawn a great deal of attention. However, power allocation in a cooperative network, where users who act as relays for each other and who utilize non-trivial codes, remains a challenge. With the aid of theoretical frame error rate expressions, we explore the performance of adaptive power control for decode-and-forward...
This standard specifies the electronic payment service layer and profile for Payment and Identity authentication, and Payment Data transfer for Dedicated Short Range Communication (DSRC) based applications in Wireless Access in Vehicular Environments. This standard defines a basic level of technical interoperability (vehicle-to-roadside) for electronic payment equipment, i.e. onboard unit (OBU) and...
Wireless sensor networks (WSNs) have wide applications due to these sensor nodes ease of deployment.But the security of WSNs is still an important issue. Some existed approaches mainly rely on cryptography to ensure data authentication and integrity. These approaches only address part of the problem of security in WSNs. However, these approaches are not sufficient for the unique characteristics and...
As a new application model of e-government, mobile e-government provides a new approach to improve government's efficiency, effectiveness and economy of public services. This paper deals with the current development of China's mobile e-government. We first discusses the concept of m-government, introduces relevant technologies and application fields of mobile communication technology in government,...
Self-healing key distribution schemes are particularly useful when there is no network infrastructure or such infrastructure has been destroyed. A self-healing mechanism can allow group users to recover lost session keys and is therefore quite suitable establishing group keys over an unreliable network where broadcast messages loss may occur frequently. Many self-healing key distribution schemes are...
The wireless local area network (WLAN) technology has a rapid development because its advantages of fast and high-efficient, flexible and easy in net building. Wireless network brings users convenient network service, but it also hides many security problems that hinder WLAN's development. This paper combines the accountability of IP address with trust routing to a second mechanism applied in WLAN...
Recently, the demanding requirements and use for wireless communication are increased and continue to grow. WiBro is trying to compete with Wi-Fi in coverage and data rate, while the inexpensive Wi-Fi still very popular in both personal and business use. This paper designs and implements Fixed Mobile Convergence (FMC) terminal system supported IEEE802.11 b/g/n Wi-Fi and WiBro. Terminal system of this...
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