New challenges in wireless and free space optical communications

AbstractThis manuscript presents a survey on new challenges in wireless communication systems and discusses recent approaches to address some recently raised problems by the wireless community. At first a historical background is briefly introduced. Challenges based on modern and real life applications are then described. Up to date research fields to solve limitations of existing systems and emerging new technologies are discussed. Theoretical and experimental results based on several research projects or studies are briefly provided. Essential, basic and many self references are cited. Future researcher axes are briefly introduced

Aperture-Coupled Beam-Scanning Patch Array With Parasitic Elements Using a Reconfigurable Series-Fed Phase-Shifting Structure

In this letter, we propose a reconfigurable series-fed phase-shifting structure with movable metal plate for active millimeter wave beam-scanning application. The proposed phase-shifting structure can be equivalent to a certain number of phase shifters in the series-fed network. It can be easily controlled with only one metal plate, which further simplify the design of control system for phase shifters and reduce the cost. A prototype of 1-D aperture-coupled patch array with parasitic elements at 28GHz is designed, fabricated and measured for verifying the performance of the proposed phase-shifting structure. The measurement results at 28 GHz show 1-D beam-steering capability with maximum steering angle of ∼22 deg at H-plane can be achieved, revealing great potentials for developing the simple control and cost-effective active phased array for millimeter wave wireless power transmission application

Automatic RADAR Target Recognition System at THz Frequency Band. A Review

The development of technology for communication in the THz frequency band has seen rapid progress recently. Due to the wider bandwidth a THz frequency RADAR provides the possibility of higher precision imaging compared to conventional RADARs. A high resolution RADAR operating at THz frequency can be used for automatically detecting and segmenting concealed objects. Recent advancements in THz circuit integration have opened up a wide range of possibilities for on chip applications, like of security and surveillance. The development of various sources and detectors for generation and detection of THz frequency has been driven by other techniques such as spectroscopy, imaging and impulse ranging. One of the central vision of this type of security system aims at ambient intelligence: the computation and communication carried out intelligently. The need for higher mobility with limited size and power consumption has led to development of nanotechnology based THz generators. In addition to this some of the soft computing tools are used for detection of radar target automatically based on some algorithms named as ANN, RNN, Neuro-Fuzzy and Genetic algorithms. This review article includes UWB radar for THz signal, its characteristics and application, Nanotechnology for THz generation and issues related to ATR

ENHANCING MARITIME DOMAIN AWARENESS (MDA) THROUGH THE DEPLOYMENT OF INTELLIGENT AUTONOMOUS SYSTEMS (IAS) USING COMMERCIAL 5G TECHNOLOGY

The United States Navy has been the dominate force of the sea in the last half century, but advancements in technology have given other nations the ability to narrow the gap and, in some cases, threaten U.S. superiority. The U.S. Navy, Marine Corps, and the Coast Guard are the triad forces for maritime domain protection. One area of potential vulnerability is in the littoral environment. However, emerging commercial technologies, like 5G, can expand the footprint of systems and capabilities within that environment for naval services to utilize. The private sector already has the lead in developing 5G state-of-the-art resources, which has enabled manned and unmanned systems to accomplish more tasks. One long-standing obstacle for the naval services to implement commercially available systems was the Department of Defense’s desire to be the owner and operator of any systems it employed. One benefit of utilizing existing commercial systems in naval operations would be to enhance capabilities without developing a completely new system. This thesis explores current and projected abilities of a commercial 5G technology for employment by U.S. naval services. Testing of 5G millimeter wave was conducted for this research. This thesis also examines a theorized new system that integrates commercial systems to satisfy naval requirements.Lieutenant Commander, United States NavyApproved for public release. Distribution is unlimited

Multi-layer Utilization of Beamforming in Millimeter Wave MIMO Systems

mmWave frequencies ranging between (30-300GHz) have been considered the perfect solution to the scarcity of bandwidth in the traditional sub-6GHz band and to the ever increasing demand of many emerging applications in today\u27s era. 5G and beyond standards are all considering the mmWave as an essential part of there networks. Beamforming is one of the most important enabling technologies for the mmWave to compensate for the huge propagation lose of these frequencies compared to the sub-6GHz frequencies and to ensure better spatial and spectral utilization of the mmWave channel space. In this work, we tried to develop different techniques to improve the performance of the systems that use mmWave. In the physical layer, we suggested several hybrid beamforming architectures that both are relatively simple and spectrally efficient by achieving fully digital like spectral efficiency (bits/sec/Hz). For the mobility management, we derived the expected degradation that can affect the performance of a special type of beamforming that is called the Random Beamforming (RBF) and optimized the tunable parameters for such systems when working in different environments. Finally, in the networking layer, we first studied the effect of using mmWave frequencies on the routing performance comparing to the performance achieved when using sub-6 GHz frequencies. Then we developed a novel opportunistic routing protocol for Mobile Ad-Hoc Networks (MANET) that uses a modified version of the Random Beamforming (RBF) to achieve better end to end performance and to reduce the overall delay in delivering data from transmitting nodes to the intended receiving nodes. From all these designs and studies, we conclude that mmWave frequencies and their enabling technologies (i.e. Beamforming, massive MIMO, ...etc.) are indeed the future of wireless communicatons in a high demanding world of Internet of Things (IoT), Augmented Reality (AR), Virtual Reality (VR), and self driving cars