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This paper investigates the effect of bringing together a triangular tip edge and tapered tip edge at the longest arm split gap of a circular split ring and its effect towards the electric and magnetic field. Conducted using tetrahedral mesh type frequency based numerical simulation by modeling the behavior of the circular rings located centered wise in a standard WR159 waveguide in comparison to...
This paper proposes the LCX-MIMO antenna system, which can multiplex multiple antennas on a Leaky Coaxial Cable (LCX). To multiplex antennas, the delay and phase coded slots on a LCX is proposed. Different code is assigned to every LCX-MIMO antenna. In the paper, the configuration of an LCX-MIMO system, theoretical analysis and design methods are described. Analytical results and simulation calculation...
This paper presents error vector magnitude (EVM) impact on the transmission performance of OFDM using a higher order modulation scheme such as 256- and 1024-QAM by link-level simulations. BER performance is highlighted as parameters of coding rates for 256- and 1024-QAM in the presence of EVM degradation. Using these results, we clarify the relation of spectral efficiency and channel quality, such...
WAIC (Wireless Avionics Intra Communications) is a wireless communication system connecting the avionics in the aircraft. This system is currently researched by AVSI (Aerospace Vehicle Systems Institute), ICAO (International Civil Aviation Organization), and ITU (International Telecommunication Union) to substitute cable redundancy in the avionics system. Current stage of the development is to determine...
This articles presents several new and simple closed-form asymptotic approximations for the average symbol error rate (ASER) performance measure of digital communication systems (with/without diversity transceivers) impaired by additive white Gaussian noise (AWGN) and multipath fading. In particular, a new class of asymptotic approximations for the ASER is derived by utilizing a normalized asymptotic...
This paper presents a printed electrically small monopole antenna for outdoor parking wireless car detector. The system relies on a network of wireless sensors (one for each parking space) to transmit whether or not a space is occupied using the 868 MHz and 915 MHz ISM bands. In parking, the maximum distance separating two cars doesn't exceed 5m. However, the wireless detector has to communicate with...
IP mobility becomes more important with the emergence of various wireless communication technologies. Users move within the same wireless communication technologies or between different wireless communication technologies. Therefore, Internet Engineering Task Force (IETF) introduced Proxy Mobile IPv6 (PMIPv6) to cope with the IP mobility problem. PMIPv6 is a network-based mobility management where...
Maximum target coverage with minimum number of sensor nodes, known as MCMS problem, is an important problem in Directional Sensor Networks (DSNs). Existing solutions allow individual sensor nodes to determine the sensing direction for maximum target coverage which causes sensing coverage redundancy as well as high energy consumption. Gathering nodes into clusters might provide a better solution to...
Although, ZigBee [21] provided a table-free Tree routing algorithm together with an addressing scheme for resource constrained IEEE 802.15.4 [15] devices, it is applicable for symmetric limited-sized tree networks only [6, 7, 8, 9]. This paper has presented an efficient routing algorithm and a flexible, variable-length addressing scheme based on prefix code. The scheme eliminates routing tables and...
Applications in wireless sensor networks (WSNs) sometimes cannot deliver the quality required by users due to packet loss and node leaving. There is a trade-off between energy and quality: increasing quality requires energy, and decreasing energy invites a lack of quality. To adjust the trade-off, actions which make changes to the energy and quality condition are required. There has been previous...
This paper investigates the indoor activity recognition issue and proposes a novel recognition framework by exploring WiFi ambient signals. The key idea is to use data mining techniques to abstract footprints of different activities on the radio signal strength (RSS) data. Our experiments show that even using a single feature and the common k-NN classifier activities such as walking, sitting and standing...
Sustaining the operation of street lights incurs substantial financial and environmental cost. Consequently, adaptive lighting systems have been proposed incorporating ad-hoc networking, sensing, and data processing, in order to better manage the street lights and their energy demands. Evaluating the efficiency and effectiveness of these complex systems requires the modelling of vehicles, road networks,...
The demand for high data rate and reliable quality of service has increased in nowadays. Multi-user will induce other cells interference which severely degrades the system performance. In this paper, the interference alignment (IA) techniques in uplink (UL) coordinated multipoint (CoMP) system with three different dynamic information selection (DIS) schemes are proposed to enhance the performance...
We propose a model for predicting the path loss of a sloped area in a microcell service area of a mobile communication system. This is the prediction model to be proposed that targets a microcell. For practical use, a model requires parameters such as the base station height, angle of the sloped area, and distance from the base station to the sloped area. The proposed model uses a correction method...
This paper describes the design of the power amplifier (PA) for 5GHz WLAN transmitter. In order to realize the high power added efficiency (PAE), impedance matching circuit is calculated by using the load-pull method. In this case, output impedance of the PA is different from 50 ohm. Our proposed 5 GHz class-A PA matched to the impedance of maximum PAE is designed. This PA has 9.82 dB of gain and...
Wireless communication systems often require accurate channel state information (CSI) at the receiver side. Typically, the CSI can be obtained from channel impulse response (CIR). Measurements have shown that the CIR of wideband channels are often sparse. To this end, the least mean square (LMS)-based algorithms have been used to estimate the CIR at the receiver side, which unfortunately is not able...
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