Showing papers by "Mohammed Abo-Zahhad published in 2020"

Efficient vehicle detection and tracking strategy in aerial videos by employing morphological operations and feature points motion analysis

Abstract: Real-time automatic detection and tracking of moving vehicles in videos acquired by airborne cameras is a challenging problem due to vehicle occlusion, camera movement, and high computational cost. This paper presents an efficient and robust real-time approach for automatic vehicle detection and tracking in aerial videos that employ both detections and tracking features to enhance the final decision. The use of Top-hat and Bottom-hat transformation aided by the morphological operation in the detection phase has been adopted. After detection, background regions are eliminated by motion feature points’ analysis of the obtained object regions using a combined technique between KLT tracker and K-means clustering. Obtained object features are clustered into separate objects based on their motion characteristic. Finally, an efficient connecting algorithm is introduced to assign the vehicle labels with their corresponding cluster trajectories. The proposed method was tested on videos taken in different scenarios. The experimental results showed that the recall, precision, and tracking accuracy of the proposed method were about 95.1 %, 97.5%, and 95.2%, respectively. The method also achieves a fast processing speed. Thus, the proposed approach has superior overall performance compared to newly published approaches.

Analysis and Implementation of High- Q CT Inductor for Compact and Wide- Tuning Range Ku -Band VCO

Abstract: This work presents a new structure of center tap (CT) inductor to improve the performance of Ku -band voltage-controlled oscillators (VCOs). Conventional CT inductor provided by the foundry suffers from a poor-quality ( $Q$ -) factor large area and low self-resonance frequency. These problems are solved by introducing a coupling structure. For the proposed CT inductor, despite its size is miniaturized by 51%, the $Q$ -factor is increased by 41% in the frequency range of 5–30 GHz compared to a conventional CT inductor. The measured differential inductance and quality factor of the proposed inductor are 385 pH and 22 at 12 GHz. The proposed CT inductor is used to design a compact and wide-tuning-range VCO at Ku -band in 0.18- $\mu \text{m}$ complementary metal–oxide–semiconductor (CMOS) technology, and this leads to 5.8 dB phase noise improvement compared to the use of a conventional CT inductor. The fabricated VCO has a compact core size of 140 $\mu \text{m}\,\,\times400\,\,\mu \text{m}$ only. The VCO chip oscillates from 11.7 to 13.7 GHz. The measured phase noise is −107.7 dBc/Hz at 1-MHz offset frequency at a carrier frequency of 13.7 GHz, and the dc power consumption of the VCO core is 4 mW which results in a figure of merit (FoM) normalized to the die area (FoM $_{\mathrm {A}}$ ) to be −197 dBc/Hz.

Dual-band CPW rectenna for low input power energy harvesting applications

Abstract: A dual-frequency band low input power rectenna is proposed in this study. The rectenna is comprised of a co-planar waveguide (CPW) rectifier integrated with a rectangular split ring antenna loaded by a spiral strip line. A single diode series connection topology is used to miniaturise the losses at low input power. A spiral coil in addition to two short circuit stubs are used as a matching network for maximum power transfer between the antenna and the rectifying circuit. The proposed rectenna operates at low input power with relatively high measured RF-DC conversion efficiency up to 74 % at input power of − 6.5 dBm at the first resonant frequency f 1 = 700 MHz and 70 % at − 4.5 dBm at the second operating frequency f 2 = 1.4 GHz with a resistive load of 1.9 k Ω . The measured rectenna sensitivity (the rectenna ability to receive low power with acceptable conversion efficiency) reaches up to − 20 dBm with a conversion efficiency of 47 and 36 % at f 1 and f 2 , respectively, and a DC output voltage of 0.18 V . The measured efficiency is over 50 % from − 18 to − 3.5 dBm and from − 15 to − 1.5 dBm at f 1 and f 2 , respectively.

A Comprehensive Survey of Intelligent-Based Hierarchical Routing Protocols for Wireless Sensor Networks

Abstract: Routing protocols are responsible for discovering and maintaining energy-efficient routes in wireless sensor networks (WSNs) to make reliable and efficient communication. The main aim of the routing protocol design is collecting data of the sensor field efficiently. In general, routing in WSNs can be classified into three groups: flat routing, hierarchical routing, and location routing. According to the literature, hierarchical routing has more advantages compared to other types, for example, hierarchical routing reduces the redundant data transmission and balances the load among the sensor nodes in an efficient way. Recently, many intelligent-based hierarchical routing protocols are developed for controlling the consumption power of WSNs. Selecting an appropriate routing protocol for specific applications is an important and difficult task for the designer of WSNs. Therefore, this chapter presents a comprehensive survey of the recently intelligent-based hierarchical routing protocols that are developed based on Particle Swarm Optimization, Ant Colony Optimization, Fuzzy Logic, Genetic Algorithm, and Artificial Immune Algorithm. These protocols will review in detail according to different metrics such as WSN type, node deployment, control manner, network architecture, clustering attributes, protocol operation, path establishment, communication paradigm, energy model, protocol objectives, and applications. Moreover, a comparison between the reviewed protocols is investigated here depending on delay, network size, energy efficiency, and scalability with mentioning the advantages and drawbacks of each protocol.

A wideband dielectric resonator antenna with switchable diversity patterns

Abstract: In this paper, a reduced-size dielectric resonator antenna with switchable diversity patterns is proposed. Ring- and linear-shaped slots are etched in the ground plane of the antenna so as to generate two modes $TE_{\delta 11}^x$ and $TE_{\delta 12}^x$ at a center frequency of 19 GHz. Moreover, two groups of PIN diodes are integrated into these slots to short one group of slots, and let the other group generates the required mode. Thus, the antenna is able to generate two switchable patterns with an envelope correlation coefficient of 0.4. Furthermore, the antenna size is reduced to half of its original size by placing a copper sheet over certain plane of the antenna structure. The antenna achieves wide bandwidths of 17.6–20.9 GHz (17.1 $\percnt $ ) and 18.3–21.6 GHz (13.8 $\percnt $ ) in cases of exciting $TE_{\delta 11}^x$ and $TE_{\delta 12}^x$ modes, respectively. The antenna also attainsa high gain of 7.1 and 3.2 dB at the center frequency.

Detection of Primary User in Wide-band Cognitive Radio Networks over Fading Channel using Compressed Sensing

Abstract: In wideband cognitive radio networks, Nyquist sampling rate is very challenging problem. It required expensive high speed analog to digital converter and large storage spaces. Lately, compressive sensing has been emerged as significant solution to crack the conventional sampling rate requirements. It proved the ability to sample below Shannan-Nyquist criteria and reconstructing back the signal after considerable dimensional reduction. Mostly in cognitive radio networks, energy detection is widely used due to its simple implementation and blind detection property. However, regardless that energy detection is subject to noise uncertainty as well as shadowing and fading which deteriorate its detection performance. Several articles have been published to improve energy detection performance using large number of measurements. In this paper, since, the detection performance using small number of measurements or compressed measurements achieved significant performance using energy detection under additive white Gaussian noise channel. This motivated us to investigate the performance of compressed measurements-based detection over fading channels which has not been studied yet. The proposed algorithm has been implemented using MATLAB. We also studied the tradeoff between the compression ratios and using fraction of transmitted signal and its impact on detection performance and threshold choice. In comparison with the ordinary compressed energy detection over the Rayleigh fading channel the results reveal that the proposed enhanced compressed measurements-based energy detection is better in performance of detection.