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Experimental Facilities for Wireless Sensor Networks the European WISEBED approach Sensor network technology has been under investigation for several years now and has matured to a degree which allows for commercial real-world implementations at a large scale. Before taking the step to deployment, however, it is crucial to evaluate the system, because detecting faults during runtime is extremely costly...
This paper focuses on the Physical Downlink Control Channel (PDCCH) and describes the impact of its realistic constraints on the performance in E-UTRAN LTE TDD system, particularly considering the asymmetric slot resources between downlink and uplink. It is described, when adopting the same PDCCH manager framework in LTE FDD system as in LTE FDD system, the uplink users are not prioritized sufficiently...
This paper concerns modulation recognition for blind modulated signals. We use the decision theory, which is popularly used in most researches, to discriminate eleven analog and digital modulated signals with nine key parameters. The carrier frequency is important to calculate some other key parameters. However, for the blind signals, the carrier frequency is unknown, so we propose a method for estimating...
In this paper, we study the optimal structure of the source precoding matrix and the relay amplifying matrices for multiple-input multiple-output (MIMO) relay communication systems with parallel relay nodes. In particular, a nonlinear decision feedback equalizer (DFE) is used at the destination node, and the minimal mean-squared error (MMSE) criterion is used to detect the transmitted signal at each...
The novel structure of high rate (3,L) regular QC-LDPC codes based on circulant permutation matrices are presented in this paper. The parity-check matrix of the proposed code consists of permutation matrices, their transpose matrices and identity matrices. With this new method, the proposed code is free from girth 4, girth 6, and sometimes girth 8. The construction of parity-check matrix of the proposed...
In this work, we focus on the use of network coding in a wireless sensor network where data is already encoded at the source node with fountain codes, in particular LT or Raptor codes. These codes have a specific degree distribution to follow in order to obtain an efficient decoding process. However, adding a layer of network coding on such packets triggers a distorsion of the degree distribution...
This paper addresses a transmission scheduling for wireless multi-hop network employing physical layer wireless network coding (PL-WNC). With PL-WNC, two distant nodes first transmit packets to an intermediate relay simultaneously, which then amplifies and forwards the received signal. The destination nodes decode the desired signals by using the a priori information which are their own packets or...
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...
To accurately determine the location of every sensor in large wireless sensor networks is normally very computation intensive and hence, is not cost-effective. On the other hand, a coarse estimate of the sensors' location is usually sufficient for many applications. The Area Localization Scheme (ALS) has been proposed as a scheme that estimates the position of every sensor within a certain region...
In this paper, the sensor node deployment schemes are studied for the all optical fiber sensor networks (AOFSN). Sensor node deployment strategy is very crucial to the sensing efficiency in terms of the high sensing accuracy and low sensing cost, etc. High sensing accuracy requires high coverage ratio and low blind ratio, while low sensing cost requires fewer amounts of sensor nodes/switches and low...
This paper proposes a link setup method of “SKYMESH,” which is an ad hoc communication system, temporarily established in the sky by balloons holding communication nodes. The SKYMESH can be used as emergency communication systems when telecommunication infrastructure is damaged for large-scale natural disaster. It was reported that a link between balloons was unstable due to swing of balloons. This...
The proliferation of wireless transceivers and the availability of unlicensed band has given a boost to the deployment of wireless networks, with IEEE802.11/WiFi being the major driver in this arena. We consider a wireless mesh network designed for long distance communication with a typical deployment scenario of a maritime mesh network. This network uses an antenna system made up of multiple fixed-beamwidth...
A negative index metamaterial antenna is presented in this paper for ultra-wideband (UWB) applications; which operates in C and X-bands. The proposed antenna is composed of three-unit cells of left-handed metamaterial (LHM) where these LHM unit cells are composed of a combination of modified octagonal spiral resonator (OSR), octagonal split-ring resonator (OSRR), capacitance-loaded strip (CLS), and...
In order to support development of third generation partnership project long term evolution (3GPP LTE) packet scheduling algorithms, research has been conducted into several radio propagation effects. The radio channels of interest are the downlink (eNodeB to user equipment) of LTE mobile networks. Through network simulator modification and repeated testing the effects of error and delay in reporting...
This paper proposes a protocol proxy scheme that can emulate the open shortest path first (OSPF) protocol in an effective and flexible manner. It is implemented in our developed network emulator, which is used to test network controllers for IP optical network management. In the protocol scheme, OSPF protocol emulation is achieved by combining an OSPF protocol proxy (introduced here) and an OSPF peer...
Multi-region fiber sensing system using high time resolution tunable subpicosecond pulse correlation OTDR has been developed. This pulse correlation OTDR technique uses flexible repetitional rate pulse and intensity partial reflection regions along the long fiber. It can reach to a high time resolution of less than 1 ps and a high spatial resolution of less than 0.2 mm. This system can select the...
In wavelength division multiplexing (WDM) mesh networks, wavelength utilization is limited by the mismatch between the high bandwidth that one wavelength can provide and the relatively low bandwidth request of a single connection. Traffic grooming which grooms multiple connections onto one wavelength is a desirable technique to improve resource utilization. However, with unpredictable traffic demand,...
This paper studies the effects of Single and Dual physical link failures to the stability of WDM networks when deployed as regular 3-degree structures. The failure impact on the source-destination pair connections is evaluated for the different topology scenarios. In this way it is possible to provide an overview of the failure effects and their relation to network metrics such as availability or...
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