155 research outputs found
Electromagnetic Waves Scattering Characteristics of Metasurfaces
No full textAlmost extreme control of electromagnetic fields is achievable using metamaterial and metasurfaces. This chapter details design techniques, challenges, and possible solutions of diffraction type, transmitted, specular, and absorptive type of metasurfaces in an attempt to achieve extraordinary device performance for a particular application. In metasurfaces, the transmission can also involve scattering using the phenomenon of diffraction, which is directly defined by the properties of the metasurface. Electromagnetic wave scattering patterns dependent on the incident polarization can be tailored by the encoded metasurfaces with regular sequences. On contrast, polarization-insensitive diffusion-like scattering can also be successfully achieved by digital metasurface encoded with randomly distributed coding sequences leading to substantial suppression of backward scattering in a broadband microwave frequency. It is believed that controlling the electromagnetic waves reflected from and transmitted through intelligently designed metasurfaces can shape the future of the communication industry.<br/
Beamformer development challenges for 5G and beyond
No full textIn this chapter, we first discussed the definitions that are vital to understand the working of a beamformer. We then classified the beamformer based on the architecture, frequency of operation and a use case. These clarifications are done keeping in mind the future technological advancements in the communication industry. Beamformer architectures are further divided into purely analog, digital and hybrid types, when each one of them has a specific need in specialized communication standards. Frequency bands of operations are divided into the well-known 5G sub bands that are sub-6-GHz and mmWave bands. We further discussed the ways in which a beamformer function differs when they are operating at different frequency bands. Lastly, we classified beamformers in terms of their utility as a fixed or mobile radio in a communication system. State-of-the-art beamformer examples are comparatively analyzed to better predict the most suitable choice for a given classification of beamformers in the 5G and beyond applications
Target Location Using Dual Beam Directional Modulated Circular Array
No full textData underpinning Fusco, V., Chepala, A., and Abbasi, M. in 'Target Location Using Dual Beam Directional Modulated Circular Array' in IEEE Transactions on Antennas and Propagation, 2018
Performance of a 28 GHz Two–Stage Rotman Lens Beamformer for Millimeter Wave Cellular Systems
No full textData underpinning Abbasi, M., Tataria, H., Fusco, V., and Matthaiou, M. 'Performance of a 28 GHz Two–Stage Rotman Lens Beamformer for Millimeter Wave Cellular Systems' in Proceedings of European Conference on Antennas and Propagation (EuCAP), 201
Constant–εr Lens Beamformer for Low–Complexity Millimeter–Wave Hybrid MIMO
No full textData underpinning Abbasi, M., Fusco, V., Tataria, H., and Matthaiou, M. Constant–εr Lens Beamformer for Low–Complexity Millimeter–Wave Hybrid MIMO in IEEE Transactions on Microwave Theory and Techniques, 2019
Robust Estimator for Lens-based Hybrid MIMO with Low-Resolution Sampling
No full textData Underpinning Vlachos, E., Thompson, J., Abbasi, M. and Fusco, V. 'Robust Estimator for Lens-based Hybrid MIMO with Low-Resolution Sampling' in Proceedings of 19th IEEE International Workshop On Signal Proceedings Advances in Wireless Communications (2019
Lens–Based Beamformer for Low–Complexity Millimeter–Wave Cellular Systems
No full textData underpinning Abbasi, M., Fusco, V., Tataria, H., and Matthaiou, M. 'Lens–Based Beamformer for Low–Complexity Millimeter–Wave Cellular Systems' in Proceedings of ESA Workshop on Millimetre-Wave Technology and Applications, 201
Receiver Array Thinning Using Digitally Assisted Mills Cross
No full textData underpinning Abbasi, M. and Fusco, V. in 'Receiver Array Thinning Using Digitally Assisted Mills Cross' (2018), Proceedings of the the 12th European Conference on Antennas and Propagation (EuCAP 2018
Development challenges of millimetre-wave 5G beamformers
No full textBeamforming is the central concept that can make millimeter‐wave (mmWave) a viable solution by solving challenges of link‐budget, cost, power, form factor, complexity, regulatory constraint, and so on. Before deployment of mmWave beamforming solution for 5G, and possibly beyond, several fundamental questions need to be answered. Some of them include hardware constraints, performance matrices, realistic propagation channel models including impairments due to obstacles such as body, blockages due to casings, phase noise, a model for spatial‐temporal variations in channels, and advanced MIMO techniques for multi‐carrier and multiuser communications. The site constraints and massive non‐line‐of‐sight transmission within the urban environment are severely questioning the conventional terrestrial low power node deployments that used to work well at low operational frequencies (sub‐6 GHz). In addition to this, in beamforming technology using massive antenna arrays, the coordination of the users and beams at the transmitter and receiver end within a large network are very challenging. In this article, we comprehensively investigate some of the most prominent and best practice solutions that attempted to answer these challenging questions
On the Impact of Spillover Losses in 28 GHz Rotman Lens Arrays for 5G
No full textData underpinning Abbasi, M., Tataria, H., Fusco, V., and Matthaiou, M. 'On the Impact of Spillover Losses in 28 GHz Rotman Lens Arrays for 5G' in IEEE MTT-S International Microwave Workshop Series on 5G Hardware and System Technology (IMWS-5G), 201
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