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Open access

Ramya Jothikumar and Nakkeeran Rangaswamy

Abstract

The breadth first signal decoder (BSIDE) is well known for its optimal maximum likelihood (ML) performance with lesser complexity. In this paper, we analyze a multiple-input multiple-output (MIMO) detection scheme that combines; column norm based ordering minimum mean square error (MMSE) and BSIDE detection methods. The investigation is carried out with a breadth first tree traversal technique, where the computational complexity encountered at the lower layers of the tree is high. This can be eliminated by carrying detection in the lower half of the tree structure using MMSE and upper half using BSIDE, after rearranging the column of the channel using norm calculation. The simulation results show that this approach achieves 22% of complexity reduction for 2×2 and 50% for 4×4 MIMO systems without any degradation in the performance.

Open access

Budi Setiyanto, Risanuri Hidayat, I Wayan Mustika and Sunarno

Abstract

Deep-fading can decline the quality of the received signal to below threshold, and interrupts the reception-success (generating an outage or time-out). In DVB-T2 (Digital Video Broadcasting Terrestrial Second Generation) receiver, such interruption can be identified from the displayed-picture. Multiple-antenna is one of techniques to mitigate such problem. This paper presents a multiple-antenna method for receiving the DVB-T2 signal. At any time, one of antennas is selected where the selection action is controlled by the recovered-picture. In case of using two antennas, field-measurement was conducted to collect the real data, later used in the simulation of the proposed algorithm. The result showed its capability to increase the portion of cumulative reception-success duration up to approximately 1.53 times with respect to its equivalent single-antenna.

Open access

Syed Shakeel Hashmi, Syed Abdul Sattar and K. Soundararajan

Abstract

Fairness provisioning in heterogeneous networks is a prime issue for high-rate data flow, wherein the inter-connectivity property among different communication devices provides higher throughput. In Hetnet, optimal resource utilization is required for efficient resource usage. Proper resource allocation in such a network led to higher data flow performance for real-time applications. In view of optimal resource allocation, a resource utilization approach for a reconfigurable cognitive device with spectrum sensing capability is proposed in this paper. The allocation of the data flow rate at device level is proposed for optimization of network fairness in a heterogeneous network. A dynamic approach of rate-inference optimization is proposed to provide fairness in dynamic data traffic conditions. The simulation results validate the improvement in offered quality in comparison to multi-attribute optimization.

Open access

Ehsan Panahifar and Alireza Hassanzadeh

Abstract

In this paper a modified signal feed-through pulsed flip-flop has been presented for low power applications. Signal feed-through flip-flop uses a pass transistor to feed input data directly to the output. Feed through transistor and feedback signals have been modified for delay, static and dynamic power reduction. HSPICE simulation shows 22% reduction in leakage power and 8% of dynamic power. Delay has been reduced by 14% using TSMC 90nm technology parameters. The proposed pulsed flip-flop has the lowest PDP (Power Delay Product) among other pulsed flip-flops discussed.

Open access

Huanqing Zhang, Hongwei Ge and Jinlong Yang

Abstract

Probability hypothesis density (PHD) filter is a suboptimal Bayesian multi-target filter based on random finite set. The Gaussian mixture PHD filter is an analytic solution to the PHD filter for linear Gaussian multi-target models. However, when targets move near each other, the GM-PHD filter cannot correctly estimate the number of targets and their states. To solve the problem, a novel reweighting scheme for closely spaced targets is proposed under the framework of the GM-PHD filter, which can be able to correctly redistribute the weights of closely spaced targets, and effectively improve the multiple target state estimation precision. Simulation results demonstrate that the proposed algorithm can accurately estimate the number of targets and their states, and effectively improve the performance of multi-target tracking algorithm.

Open access

Andrzej Skorupski

Abstract

This paper presents a new approach to designing reversible circuits. Reversible circuits can decrease energy dissipation theoretically to zero. This feature is a base to build quantum computers. The main problem of reversible logic is designing optimal reversible circuits i.e. circuits with minimal gates number implementing the given reversible function. There are many types of reversible gates. Most popular library is a set of three types of gates so called CNT (Control, NOT and Toffoli). The method presented in this paper is based only on the Toffoli gates. A graphical representation of the reversible function called s-maps is introduced in the paper. This representation allows to find optimal reversible circuits. The paper is organized as follows. Section 1 recalls basic concepts of reversible logic. In Section 2 a graphical representation of the reversible functions is presented. Section 3 describes the algorithm whereby all optimal solutions of the given function could be obtained.

Open access

Pawel Linczuk, Rafal D. Krawczyk, Wojciech Zabolotny, Andrzej Wojenski, Piotr Kolasinski, Krzysztof T. Pozniak, Grzegorz Kasprowicz, Maryna Chernyshova and Tomasz Czarski

Abstract

We present a feasibility study of fast events parameters estimation algorithms regarding their execution time. It is the first stage of procedure used on data gathered from gas electron multiplier (GEM) detector for diagnostic of plasma impurities. Measured execution times are estimates of achievable times for future and more complex algorithms. The work covers usage of Intel Xeon and Intel Xeon Phi - high-performance computing (HPC) devices as a possible replacement for FPGA with highlighted advantages and disadvantages. Results show that less than 10 ms feedback loop can be obtained with the usage of 25% hardware resources in Intel Xeon or 10% resources in Intel Xeon Phi which leaves space for future increase of algorithms complexity. Moreover, this work contains a simplified overview of basic problems in actual measurement systems for diagnostic of plasma impurities, and emerging trends in developed solutions.

Open access

Emansa Hasri Putra, Risanuri Hidayat, Widyawan and I Wayan Mustika

Abstract

Wireless Multimedia Sensor Networks (WMSNs) advances can route multimedia applications from source nodes to a sink. However, they require energy efficiency and network lifetime due to limited power resources in the sensor nodes. This paper proposes an energy-efficient routing optimization for multimedia transmission in WMSNs. The optimization utilizes a routing algorithm based on the dynamic programming. The routing optimization algorithm selects intermediary nodes which have minimum energy above 60%. Then, the priority selection of paths immediately finds neighboring nodes which have the greatest energy minimum. If there is the same minimum energy between the neighboring nodes, then the second priority selection is based on smaller link cost.

Open access

Adil El Abboubi, Fouzia Elbahhar, Marc Heddebaut and Yassin Elhillali

Abstract

this paper, an energy consumption model is developed and exploited to evaluate the electrical energy consumption of ultra-wideband impulse radio (UWB-IR) systems. We develop the energy consumption models and our comparative study, on the one hand, for a system based single-input singleoutput (SISO) configuration and a multiple-input single-output (MISO) and, on the other hand, for a time reversal TR-MISO configuration and for MISO alone configuration. We consider an indoor propagation environment based on the 802.15.4a channel model. The results show very different behaviors depending on the propagation conditions, the number of antennas used, or on the number of transmitted symbols. Using such a model, a radiofrequency designer can obtain significant inputs to optimally select an adequate configuration to design an adaptive energyaware UWB-IR system.

Open access

C. Suganthi Evangeline and S. Appu

Abstract

A special type of Mobile Ad-hoc Networks (MANETs) which has frequent changes of topology and higher mobility is known as Vehicular Ad-hoc Networks (VANETs). In order to divide the network into groups of mobile vehicles and improve routing, data gathering, clustering is applied in VANETs. A stable clustering scheme based on adaptive multiple metric combining both the features of static and dynamic clustering methods is proposed in this work. Based on a new multiple metric method, a cluster head is selected among the cluster members which is taken from the mobility metrics such as position and time to leave the road segment, relative speed and Quality of Service metrics which includes neighborhood degree, link quality of the RSU and bandwidth. A higher QoS and cluster stability are achieved through the adaptive multiple metric. The results are simulated using NS2 and shows that this technique provides more stable cluster structured with the other methods.