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Despite the fact that cooperative localization approaches stand well in Wireless Sensor Networks (WSNs), they impose challenge of increased energy consumption resulting from the important communication overhead required to accomplish the localization task. In this paper, we developed an Energy Aware Cooperative Localization approach (EACL) based on using a recursive localization system. Obviously,...
Detection of spectrum holes in Cognitive Radio Networks (CRNs) is possible using theory of compressive sensing (CS). At the same time, these unlicensed Cognitive secondary users (SUs) must reliably detect the presence of licensed users or owners of spectrum holes to avoid interference. Precise localization of the transmitting nodes is a complicated but important problem for operation of Cognitive...
Cognitive Radio (CR) technology constitutes a new paradigm where wireless devices can access the spectrum left unused by licensed or primary users in an opportunistic way. At the same time, these unlicensed secondary users (SUs) must reliably detect the presence of licensed primary transmission to avoid interfering with them. Information about primary users (PUs) locations are very important in Cognitive...
With the discontinuity of Selective Availability (SA) by U.S government, obtaining accuracies upto tens of meters by GPS system became simpler. Though the performance level reached to millimeter level accuracy, it is only restricted to military domains and is provided under Precise Positioning Service (PPS) standards. The two different GPS services include PPS and Standard Positioning Service (SPS)...
In this paper an infrared (IR) indoor local positioning system (LPS) is presented. The most relevant low level design aspects are addressed. Using sinusoidal amplitude-modulation (AM) of an infrared carrier, differential distances between a mobile emitter, the position of which is to be obtained, and fixed receivers are measured. The system may yield accuracies at the level of a few cm and addresses...
Existing techniques for measuring available bandwidth measure the available bandwidth at bottlenecks along the path, and most of them do not specify the bottleneck location. In this paper, we propose an end-to-end measurement method for the hop-by-hop available bandwidth along a network path. Such a technique can facilitate advanced traffic control, especially in heterogeneous network environments...
While wireless localization technology has rapid development in recent years, the need for a certain number of beacons to accomplish localization and guarantee adequate accuracy is a key challenge. For example, approaches that based on trilateration or AOA (Angle Of Arrival), at least three beacons are needed and adding the number of beacons can improve localization accuracy to some extent. However,...
This paper analyzes the observability of estimating simultaneously the initial position and velocity of a constant velocity source by two fixed receivers using TDOA measurements observed many a time. From the geometrical means of vector operations, it arrives at the conclusion that the conditions are similar to those in the general source localization by multi-receivers using TDOA. Then the Cramer-Rao...
In this paper a new high resolution GPS-based system for indoor is presented. The common systems used for this purpose are not very accurate and usually expensive. The proposed approach allows to obtain systems which are both very accurate and low cost. It is based on the wideband spread spectrum technique at 24 GHz, and achieves an accuracy better than 0.5 millimeter even when the target is moving...
The deployment of Galileo and the modernization GPS will provide additional signals with increasingly complex modulations and multiplexing schemes, enabling performance enhancements in terms of availability, accuracy, and robustness. With the Galileo Initial Operational Capability (IOC) scheduled around mid-decade with fourteen satellites already ordered in January 2010, 4 additional ordered in 2012...
This paper examines the performance of locating a mobile station (MS) at a GSM network based on received signal strength (RSS) of practical measurements. Each mobile station can scan RSS measurements of the downlink control channels transmitted by its surrounding base stations. Then these measurements can be used to obtain the MS location by means of calculating algorithm [1]. We measured the received...
Spectrum sensing is used to detect the unexploited sub-bands in the radio environment. In order to improve the accuracy of the spectrum sensing, the cooperative spectrum sensing method is assumed to be the best method to be used. However, it consumes power by exchanging the sensing results among the participating nodes. An efficient cooperative spectrum sensing method is proposed in this paper to...
The concept of cooperative vehicle safety (CVS) is based on cooperation of vehicles in achieving real-time situation awareness for the purpose of safer (and possibly autonomous) driving. Since CVS is a safety system, situation awareness has to be real-time with high accuracy. Cooperation in the context of CVS is achieved through vehicular networks that are tuned to the purpose of vehicle state tracking...
The available bandwidth on an end-to-end network path is an important metric for detecting network congestion, adapting transmission rate, configuring paths and topologies on overlay networks, and so on. The existing available bandwidth measurement techniques aimed only at knowing available bandwidth of the bottleneck part on the path and most of them do not specify where is the bottleneck, and they...
Radar networks show an interesting potential for safety and comfortable applications such as indoor monitoring or short-range automotive monitoring system. This paper presents our novel estimation algorithm of a target position. Especially we evaluate the performance about estimation accuracy and resistance to ghost targets under multipath environment. In above applications, the robust estimation...
Classic localization methods in conventional radar cannot be used to multiple-input multiple-output radar directly. In this paper, we proposed a new localization model for MIMO radar system, which make hyperbolic location method can be extended to MIMO radar. TOAs equations are build from multipath between transmitters and receivers to estimate the target position. The equations are redundant since...
Global Navigation Satellite Systems (GNSS) provide positioning service to civil applications. At the end user's side, these positioning services will have different position accuracy levels when satellite signal configurations and receiver noise levels are different. In this paper, a position error modeling is presented using a black-box approach. Using this approach, end users will treat the entire...
This article proposes a new method of maintaining synchronization for the correlation receiver. I use PSK of fifth phase for this telecommunication system. However, we can use this method for the correlation receiver of any other demodulation. As usual method for the internal synchronization, there is DDL (Delay Lock Loop). But I thought that we can directly calculate the value of phase difference,...
In this paper, a computational function based on the CORDIC algorithm for location estimation is proposed. Position awareness is a desirable feature for many applications of Wireless Sensor Networks. The Received Signal Strength Indicator (RSSI) values provide a feasible way for relative position estimation. The relationship of precision to bit length for IEEE 754 is discussed. Finally, the hardware...
In this paper, we show the characteristics of the threshold-based IR-UWB location positioning system by experiment. We found that this system provides distance-dependent accuracy because the arrival time of the pulse is detected by threshold using 1-bit ADC (Analog to Digital Convertor). We also propose a simple compensation method based on measurement to improve positioning accuracy. The proposed...
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