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Showing papers by "Mohammed Abo-Zahhad published in 2019"


Journal ArticleDOI
22 Oct 2019-Sensors
TL;DR: This work presents an effective algorithm for vehicle detection and counting in complex traffic scenes by combining both convolution neural network (CNN) and the optical flow feature tracking-based methods.
Abstract: Automatic vehicle detection and counting are considered vital in improving traffic control and management. This work presents an effective algorithm for vehicle detection and counting in complex traffic scenes by combining both convolution neural network (CNN) and the optical flow feature tracking-based methods. In this algorithm, both the detection and tracking procedures have been linked together to get robust feature points that are updated regularly every fixed number of frames. The proposed algorithm detects moving vehicles based on a background subtraction method using CNN. Then, the vehicle’s robust features are refined and clustered by motion feature points analysis using a combined technique between KLT tracker and K-means clustering. Finally, an efficient strategy is presented using the detected and tracked points information to assign each vehicle label with its corresponding one in the vehicle’s trajectories and truly counted it. The proposed method is evaluated on videos representing challenging environments, and the experimental results showed an average detection and counting precision of 96.3% and 96.8%, respectively, which outperforms other existing approaches.

45 citations


Journal ArticleDOI
TL;DR: An optimization problem for power allocation is formulated and solved to improve the secrecy performance of the network by minimizing the asymptotic SOP for both Col and Non-Col cases.
Abstract: This paper investigates the secrecy performance of a multiuser system that utilizes transmit antenna selection scheme at the base station and adopts threshold-based selection diversity opportunistic scheduling over legitimate nodes. The legitimate transmission suffers from the presence of noncolluding (Non-Col) and colluding (Col) multiple passive eavesdroppers. Both the legitimate and eavesdropping nodes are assumed to suffer from co-channel interference (CCI) signals from independent channels that follow Rayleigh fading. Closed-form expressions for the probability density functions and cumulative density functions of the end-to-end signal-to-interference-plus-noise ratio for both eavesdropping scenarios in the presence of CCI signals are derived. In addition, closed-form expressions for the network secrecy outage probability (SOP) for Non-Col/Col scenarios are derived. At the high signal-to-noise ratio values, closed-form expressions for the asymptotic secrecy outage probabilities are obtained. Following this obtained asymptotic analysis, an optimization problem for power allocation is formulated and solved to improve the secrecy performance of the network by minimizing the asymptotic SOP for both Col and Non-Col cases. The derived analytical expressions are then validated using both simulations and numerical results.

17 citations


Journal ArticleDOI
TL;DR: The designated antenna resembles good candidate for 5G wireless communication systems and is inserted in multiple-input multiple-output (MIMO) system.
Abstract: A dual-band mm-wave compact antenna is proposed in this paper. A quarter-wave half-slot resonator is used instead of a half-wave slot to achieve miniaturization of the antenna size. The antenna consists of two stacked half-slot resonators to radiate at two frequencies, f 1 = 24 GHz and f 2 = 28.5 GHz, with the same microstrip line feed. By using this stacked structure, a dual-band is obtained and the two resonant frequencies become independently matched with a minor effect on each other. Measurements show the proposed antenna has an impedance bandwidths of 6.3% and 15% at f 1 and f 2 , respectively; furthermore, the antenna has good radiation characteristics. The antenna gains in addition to the radiation efficiencies at f 1 and f 2 , are 3.5dBi, 92%, 4dBi, and 95% respectively. The equivalent circuit model for the proposed antenna is introduced to show the electrical behavior of the antenna. Finally, the antenna design is inserted in multiple-input multiple-output (MIMO) system. The proposed antenna is analyzed and optimized using ANSYS HFSS EM simulator and its equivalent circuit is performed by Agilent Advanced Design System (ADS). The simulated as well as measured results show good agreement. The designated antenna resembles good candidate for 5G wireless communication systems.

17 citations


Proceedings ArticleDOI
01 Oct 2019
TL;DR: Simulation results show that the used matching algorithm for users admission is of low complexity as well as the existence of a Walrasian equilibrium point for the channels allocation problem.
Abstract: The introduction of cognitive radio technology in licensed 5G networks could significantly enhance the overall system capacity and number of served users. In this context, this work discusses the admission of new cognitive radio secondary users (SUs) in the fifth generation (5G) Heterogeneous Networks (HetNets) as well as the allocation of the channels over the secondary cognitive network, using a many-to-one matching game and auctions theory. Simulation results show that the used matching algorithm for users admission is of low complexity as well as the existence of a Walrasian equilibrium point for the channels allocation problem.

4 citations


Proceedings ArticleDOI
01 Apr 2019
TL;DR: This paper considers a dynamic spectrum sensing system consisting of both non-cooperative mobile cognitive radio(CR) secondary users and mobile non-cognitive radio primary users, and two mobility models are adopted.
Abstract: Spectrum sensing is an essential operation in cognitive radio networks. In this paper, we consider a dynamic spectrum sensing system consisting of both non-cooperative mobile cognitive radio(CR) secondary users and mobile non-cognitive radio primary users. Key performance metrics such as detection capability and sensing capacity are evaluated. Two mobility models are adopted for both secondary and primary users. The relative distance distribution associating the independent mobile users is analyzed and given in both 1- and 2-dimensions. Expressions for both performance metrics are derived, and simulations are performed to validate the theoretical analyses.

2 citations


Proceedings ArticleDOI
01 Oct 2019
TL;DR: It is shown that better spectrum sensing performance can be achieved with a high probability of detection for a random mobility model and for pseudo-static movements having pause time factor, the detection performance increases.
Abstract: Spectrum sensing task is an essential operation in cognitive radio networks. As such, this paper considers the impact of primary mobile users whose location and dynamic spectrum use can be tracked and sensed by collaborative secondary users. We evaluate the probability of detection for two simplistic random mobility models by acquiring compressed signal measurements at the fusion center. The collaborative signal acquisition is to reduce the computation at the secondary user side. Combined with the recovered signal via compressed sensing, a localization technique by Kalman filtering is used to track a primary mobile user in the network region. For a random mobility model, it is shown that better spectrum sensing performance can be achieved with a high probability of detection. Further, for pseudo-static movements having pause time factor, the detection performance increases. Simulation results are given to corroborate the approach used in the evaluation.

Proceedings ArticleDOI
01 Dec 2019
TL;DR: In this article, the dynamic range of the conventional differential drive rectifier is enhanced based on leakage current reduction technique, to solve the narrow dynamic range problem of the input power and improve the output rectifier performance.
Abstract: In this paper, the dynamic range of the conventional differential drive rectifier is enhanced based on leakage current reduction technique, to solve the narrow dynamic range problem of the input power and improve the output rectifier performance. The proposed design uses auxiliary transistors to control the conductivity of the rectifying PMOS devices dynamically to reduce the reverse leakage current. Post layout simulations have been performed using 0.18 μm CMOS technology at 402 MHz with 10kΩ load resistor. The proposed rectifier increases the range of the RF input power about ten times compared to a conventional rectifier's dynamic range and reduces the reverse leakage current from ‒98 μA to ‒22 μA. It also boosts the output average voltage at high input power. In addition, the developed rectifier exhibits good performance over wide band of input frequencies up to 2.4 GHz. The proposed rectifier has a small area of about 0.19 mm2.

Proceedings ArticleDOI
01 Oct 2019
TL;DR: The results show that the increase in the number of independent mobile users following a random mobility model has an impact on the total sensing capacity over unoccupied bands.
Abstract: In this paper, we investigate the mutual mobility effect for independent multiple primary users and numerous secondary users on the spectrum sensing capability of secondary users. The proposed system model adopts two different mobility models; namely, the random walk (RWL) model and random waypoint (RWP) model with varying numbers of primary mobile users and secondary mobile users in the network. Closed-form expressions for the detection capability and normalized sensing capacity were derived. The results show that the increase in the number of independent mobile users following a random mobility model has an impact on the total sensing capacity over unoccupied bands.