Hamada Esmaiel

Aswan University | SVU · Department of Electrical Engineering

This paper proposes a double-layer structure RRT* algorithm based on objective bias called DOB-RRT*. The algorithm adopts an initial path with an online optimization structure for motion planning. The first layer of RRT* introduces a feedback-based objective bias strategy with segment forward pruning processing to quickly obtain a smooth initial pa...

Ship-radiated noise is the main basis for ship detection in underwater acoustic environments. Due to the increasing human activity in the ocean, the captured ship noise is usually mixed with or covered by other signals or noise. On the other hand, due to the softening effect of bubbles in the water generated by ships, ship noise undergoes non-negli...

It is very challenging to design an effective wireless communication system. That's because of numerous factors affecting the performance of a typical wireless communication system, such as nonlinear channel distortions and impairments. single carrier frequency division multiple access (SC-FDMA) is a multiple access scheme that is an important part...

Diabetic retinopathy (DR) is a significant cause of vision impairment, emphasizing the critical need for early detection and timely intervention to avert visual deterioration. Diagnosing DR is inherently complex, as it necessitates the meticulous examination of intricate retinal images by experienced specialists. This makes the early diagnosis of D...

The most important function of the deep learning (DL) channel equalization and symbol detection systems is the ability to predict the user’s original transmitted data. Generally, the behavior and performance of the deep artificial neural networks (DANNs) rely on three main aspects: the network structure, the learning algorithms, and the activation...

In recent years, artificial neural networks (ANNs) have grown a lot and helped solve numerous problems in wireless communication systems. We have evaluated the performance of the Bidirectional-Long-Short-Term-Memory (Bi-LSTM) recurrent neural networks (RNNs) for joint blind channel equalization and symbol detection using a variety of activation fun...

Deep learning (DL) algorithms can enhance wireless communication system efficiency and address numerous physical layer challenges. Channel state estimation (CSE) and signal detection (SD) are essential parts of improving the performance of an OFDM wireless system. In this context, we introduce a DL model as an effective alternative for implicit CSE...

In the past decades, researchers/scientists have paid attention to the physical layer of underwater communications (UWCs) due to a variety of scientific, military, and civil tasks completed beneath water. This includes numerous activities critical for communication, such as survey and monitoring of oceans, rescue, and response to disasters under th...

The world population is rapidly increasing, which in turn increases food needs. On the other hand, food production is the main cause of water withdrawal. Precision agriculture, based on the Internet of Underground Things (IoUT), has recently been proposed to reduce water withdrawals. IoUT comprises sensors and communication devices that are partial...

This article presents orthogonal frequency division multiplexing (OFDM) that is based on discrete Hartley transform (DHT) as a modulation transform for underwater acoustic (UWA) communication instead of the conventional discrete Fourier transform (DFT). The proposed DHT-OFDM scheme has the advantages of reducing the pilot overheads required to trac...

Non-orthogonal multiple access (NOMA) is considered a promising multiple access technique for fifth generation (5G) mobile networks and tactical internet due to its high spectral efficiency. Thanks to the high spectral efficiency of NOMA, it can be a strong candidate suitable for the limited channel bandwidth of underwater acoustic communication. T...

The shallow water noise shows obvious impulsive property, which greatly degrades the direction of arrival (DOA) performance due to the conventional design concept based on the Gaussian assumption. In this paper, DOA estimator in presence of impulsive noise utilising variational Bayesian inference is proposed. The Middleton's Class A noise model is...

Due to the high spectral efficiency (SE) and fast synchronization, the time-domain synchronization orthogonal frequency division multiplexing (TDS-OFDM) system has gotten much more attraction of researchers as compared to cyclic-prefix (CP) and zero padding (ZP) OFDM in terrestrial as well as underwater acoustic communication. Inter-block interfere...

The nature of the multipath channel and the peak-to-average power ratio (PAPR) are regarded as the main challenges restricting the design of a multicarrier reliable underwater acoustic (UWA) communication. This paper proposes a new scheme, precoded index modulation orthogonal frequency division modulation spread spectrum (IM-OFDM-SS), for UWA commu...

Abstract: Due to the complexity and unique features of the hydroacoustic channel, ship‐radiated noise (SRN) detected using a passive sonar tends mostly to distort. SRN feature extraction has been pro‐posed to improve the detected passive sonar signal. Unfortunately, the current methods used in SRN feature extraction have many shortcomings. Consider...

In this letter, a new method on the ${K}$ -factor estimation is proposed for wireless communications over Rician frequency-flat fading channels. Firstly, the mean and variance of the squared envelope of the received signal are respectively derived. Then, we employ them to further derive the closed-form expression for the ${K}$ -factor and final...

This letter presents a new scheme to solve the issue of high redundant energy in Unique Word Orthogonal Frequency Division Multiplexing (UW-OFDM). The proposed scheme, called Low-Redundant Energy UW-OFDM (LRE-UW-OFDM), is suitable for time-varied harsh channels such as the Underwater Acoustic (UWA) channel were inserting the UW data in the time dom...

Time-domain synchronous orthogonal frequency division multiplexing (TDS-OFDM) is presented to enhance the spectral and energy efficiency over the conventional cyclic prefix OFDM and zero padding OFDM, but the interbloc interference (IBI) between the data block and adjacent pilot symbols deteriorates its performance. The IBI is considered as the mai...

The compressive sensing (CS) technique is widely used in the field of radio-frequency channel estimation. However, in optical wireless channel (OWC) estimation, CS needed to be adapted to cope with the nonlinear distortion resultant from the electrical-to-optical and optical-to-electrical conversion process of the OWC. Therefore, a robust CS channe...

The Multiuser Direct Sequence Spread Spectrum (DSSS) has been proposed for the autonomous underwater vehicles (AUV) communication systems in a long transmission distance to transmit multiple users over the same channel bandwidth. Unfortunately, the DSSS data rate is limited by four users as a maximum due to the extensive multipath arrivals. This pa...

The limitation of the available channel bandwidth and availability of a sustainable energy source for battery feed sensor nodes are the main challenges in the underwater acoustic communication. Unlike terrestrial's communication, using multi-input multi-output (MIMO) technologies to overcome the bandwidth limitation problem is highly restricted in...

The acoustic signal transmission over the underwater channel has a limited sum rate and it consumes high power due to the properties of the underwater environment. This study attempts to use the non-orthogonal multiple access (NOMA) technologies for underwater communications. NOMA can be an attractive candidate for underwater communication due to i...

Underwater acoustic localization is a useful technique applied to any military and civilian applications. Among the range-based underwater acoustic localization methods, the time difference of arrival (TDOA) has received much attention because it is easy to implement and relatively less affected by the underwater environment. This paper proposes a...

The ubiquitous commercial Wi-Fi has brought unlimited possibilities to the smart city and the Internet of Things. Wi-Fi device-free sensing technology has received more and more attention in recent years. Counting the people in queuing is an uneasy task due to labile information. Most current counting schemes have existed in an ideal environment wi...

Due to the complexity and variability of underwater acoustic channels, ship-radiated noise (SRN) detected using the passive sonar is prone to be distorted. The entropy-based feature extraction method can improve this situation, to some extent. However, it is impractical to directly extract the entropy feature for the detected SRN signals. In additi...

Mode selection is normally used in conjunction with Device-to-Device (D2D) millimeter wave (mmWave) communications in 5G networks to overcome the low coverage area, poor reliability and vulnerable to path blocking of mmWave transmissions. Thus, producing a high-efficient D2D mmWave using mode selection based on select the optimal mode with low comp...

Mode selection is normally used in conjunction with Device-to-Device (D2D) millimeter wave (mmWave) communications in 5G networks to overcome the low coverage area, poor reliability and vulnerable to path blocking of mmWave transmissions. Thus, producing a high-efficient D2D mmWave using mode selection based on select the optimal mode with low comp...

In wireless communication systems, Rice factor ratio (RFR) defined as K/(1+K) is a key parameter not only to evaluate the quality of communication channel since it can reveal the severity of the small-scale fading, but also to be employed as a priori information for estimation of other parameters such as frequency. Consequently, its estimation is i...

In this letter, we propose a new orthogonal coding-based modulation (OCBM) scheme, in which all available transmitting subcarriers and antennas are activated at a time instant to transmit the data constellation symbols, and the indices of the activated subcarriers and antennas are also harnessed to carry information bits. Our OCBM especially addres...

Immigration to the millimeter wave (mmWave) bands has got the attention of both industry and academia for playing a crucial role in the future 5G wireless networks. Unlike the traditional sub 6 GHz bands, large segments of contiguous spectrum are available at the mmWave bands allowing multi-gigabit data rates transmission. However, signals at mmWav...

The remote Photoplethysmograph (rPPG) is recently used in evaluating heart rate (HR) from registered skin color differences through a camera. It is based on extracting HR from the small periodic color difference in the skin due to heartbeats. Selection of Region of Interest (ROI) is a critical process and its necessity includes as many skin pixels...

Quadrature spatial modulation (QSM) is one of the most prevalent transmission techniques for future wireless mobile network due to its high spectral efficiency (SE) and low complexity. However, it is restrictive to downlink of the cellular network deployments. Therefore, this paper proposes QSM for the multiuser uplink data transmission that increa...

A spatial modulation (SM) scheme has been developed as a hopeful candidate for spectral and energy-efficient wireless communication systems, as it provides a great judgment for the system performance, data transmission rate, receiver complexity, and energy/spectrum efficiency. In SM, the data is conveyed by both habitual M-ary signal constellations...

As a communication system for maritime monitoring and navigation, automatic identification system (AIS) has been employed for many years, but its service range is limited in 40 nautical miles. Fortunately, an updated service navigation system named as space-based AIS has been presented in recent years, which can provide global coverage service. How...

Analogue beamforming is normally used in conjunction with millimetre wave (mmWave) communications to overcome the high propagation and penetration losses inherent in mmWave transmissions. Thus, producing a high-efficient mmWave beamforming using low beamforming training (BT) complexity turns to be a big challenge towards ubiquitous mmWave communica...

Spatial Modulation Technologies (SMTs) are schemes that reduce inter-carrier interference (ICI), inter-channel interference, inter-antenna synchronization (IAS), and system complexity for multiple-input multiple-output (MIMO) communication systems. Moreover, high spectral and energy efficiency have rendered SMTs attractive to underwater acoustic (U...

Millimeter wave (mmWave) is a promising technology nowadays because it provides users with ultra-high data rate links with low latency time. Hence, internet of things, tactile internet and cloud computing applications which becomes an essential matter in 5G networks can be supported using it. mmWave standard, IEEE 802.11 ad, proposed using schedule...

Abstract: A full design of the Internet of Underwater Things (IoUT) with a high data rate is one of the greatest underwater communication difficulties due to the unavailability of a sustainable power source for the battery supplies of sensor nodes, electromagnetic spread weakness, and limited acoustic waves channel bandwidth. This paper presents a...

Space modulation techniques (SMTs) have emerged as promising candidates for spectral- and energy-efficient wireless communication systems since they strike a good balance among error performance, power efficiency, spectrum efficiency, and receiver complexity. In SMTs, the information is not only conveyed by the habitual M-ary signal constellatio...

Time division synchronization orthogonal frequency division multiplexing (TDS-OFDM) has been attractive due to its fast synchronization and efficient spectral efficiency over conventional cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) and zero padding orthogonal frequency division multiplexing (ZP-OFDM). However, inter-block int...

This paper proposed a new OFDM scheme called damped zero-pseudorandom noise orthogonal frequency division multiplexing (DZPN-OFDM) scheme. In the proposed scheme, ZPN-OFDM non-zero part is damped to reduce its energy, thus the mutual interference power in-between the data and training blocks with conservative the pseudo-noise conventional propertie...

Integration of the promising Millimeter wave (mmWave) technology into the legacy cellular network is one of the main challenges towards a unified 5G cellular network. However, directly controlling the access of mmWave small cells (SCs) via the LTE eNB using the conventional LTE/WLANs interworking seems to be an inefficient solution. This is due to...

Higher spectral efficiency and fast synchronization can be achieved by using time domain synchronous OFDM (TDS-OFDM). But unfortunately, it suffers from low bit error rate performance in long delay spread channels and its performance loss over fast time-varying vehicular channel. This paper proposed TDS-OFDM as a strong candidate for vehicle-to-veh...

In recent years, underwater communication (UWC) systems have been attractive in the development of civilian and military applications. However, there are many challenging issues surrounding such communication systems due to severe channel conditions such as ambient noise, frequency selectivity, multi-path with significant tap delays and Doppler shi...

This paper proposes new scheme for efficient rate allocation in conjunction with reducing peak-to-average power ratio (PAPR) in orthogonal frequency-division multiplexing (OFDM) systems. Modification of the set partitioning in hierarchical trees (SPIHT) image coder is proposed to generate four different groups of bit-stream relative to its signific...

ecently, generalized light emitting diode (LED) index modulation scheme orthogonal frequency division multiplexing (GLIM-OFDM) was suggested to Li-Fi technology. GLIM-OFDM use channel state information in its estimator and consider channel known, which is not practical assumption. In this paper, considering the Li-Fi channel as a semi-static channe...

Owing to the underwater (UW) acoustic channel characteristic (i.e. low bandwidth and the multipath spreading) the real time multimedia (i.e. image and video) transmission over underwater acoustic (UWA) channel is a very tough task. Therefore, in this paper, an acoustic millimeter-wave (mmWave) communication channel is proposed to replace the conven...

A novel transmission scheme called fully generalised spatial modulation (FGSM) is proposed for underwater communication, where any subset of available transmitting antennas (Nt) is activated at a time instant to transmit the data constellation symbol and the index of the active antenna is also harnessed to carry information. The FGSM offers better...

Underwater wireless communications (UWCs) play a major role in both civilian and military applications. The features of the underwater transmission media are big challenges towards the design of efficient and robust UWCs. Many types of propagation waves have been investigated for UWCs such as acoustic, electromagnetic, optical and magnetic inductio...

This paper presents a comparative study on millimeter wave (mmWave) location-based analog beamforming (BF) techniques based on channel estimation. Localization and compressive sensing (CS) effectively reduces mmWave BF complexity and enhance the performance of mmWave system comparable to the conventional mmWave analog BF techniques. BF techniques b...

In this letter, a novel millimeter wave (mmWave) multi-level beamforming (BF) is proposed. User positioning is used for roughly defining the area within which the mobile station (MS) is properly located. Based on this, a multi-level beam search is conducted using compressive sensing (CS) based channel estimation to find out the transmit (TX)/receiv...

Time domain synchronization orthogonal frequency division multiplexing technique (TDS-OFDM) can offer better efficiency in spectrum and energy use than standard cyclic prefix and zero padding schemes by replacing the guard interval with a pseudorandom noise sequence. In this paper, a type of frequency domain pseudorandom noise training sequence is...

This paper develops a location based analog beamforming (BF) technique using compressive sensing (CS) to be feasible for millimeter wave (mmWave) wireless communication systems. The proposed scheme is based on exploiting the benefits of CS and localization to reduce mmWave beamforming (BF) complexity and enhance its performance compared with conven...

Millimeter wave (mmWave) communication is considered as the most promising solution for future 5G cellular networks. However, it suffers from a severe propagation loss causing dramatic link quality degradation and limiting its coverage area. Antenna beamforming appears to be a suitable solution to overcome this problem and provides longer transmiss...

Time-reversed orthogonal frequency division multiplexing (TR-OFDM) has recently received attention as a promising spectral efficient scheme for single-input multiple-output communications over time-dispersive fading channels. For TR-OFDM, passive time reversal processing is used as a simple means for channel time dispersion reduction. In particular...

A novel transmission scheme called zero-pseudorandom noise training sequence orthogonal frequency division multiplexing (ZPN-OFDM) is proposed, where the frame structure of dual-pseudorandom noise (PN) padding time domain synchronous OFDM is modified by replacing the first PN sequence by a zero sequence. The new ZPN-OFDM system offers better energy...

In this paper, image transmission in underwater channels is considered. The images are encoded with forward error correction using an unequal error protection technique together with the Reed-Solomon codes and dynamic bit-rate allocation before transmitted. This paper proposes a novel rate allocation scheme for efficient image bit stream transmissi...

Due to multipath propagation and frequency selective fading, there are many obstacles for reliable and high data rate underwater acoustic (UWA) communication. The effective use of OFDM in underwater channel also suffers from its high sensitivity to carrier frequency offset, which distorts the orthogonality between subcarriers due to Inter-Carrier I...

Performance of underwater acoustic communication system is influenced on channel characteristic. Especially, an important feature of the underwater acoustic communication is multipath propagation and Doppler spread cause by the surface and bottom reflections. In this paper, we study the application of high speed image transmission using multi-carri...

Set Partitioning in Hierarchical Trees (SPIHT) is an efficient wavelet-based progressive image-compression technique, designed to minimize the mean-squared error (MSE) between the original and decoded imagery. Since underwater acoustic channel suffer from highly significant bit error rates, some mechanism to protect the encoded image required. In t...

In past decades, there has been a growing interest in the discussion and study of using underwater acoustic channel as the physical layer for communication systems, ranging from point-to-point communications to underwater multicarrier modulation networks. A series of review papers were already available to provide a history of the development of th...