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An Overview of Smart Antenna Technology for Wireless Communication
Published in Prashant Ranjan, Ram Shringar Rao, Krishna Kumar, Pankaj Sharma, Wireless Communication, 2023
Prashant Ranjan, Ram Shringar Rao, Krishna Kumar, Pankaj Sharma
The control unit can be called the brain of a smart antenna. It contains a digital signal processor (DSP), an antenna controller and a smart scanning receiver. Output of a smart scanning receiver is connected to the input of a digital signal processor (DSP), and input of the antenna controller is connected through the output of a digital signal processor (DSP). Based on several inputs, antenna feedings are controlled by the processor using optimization of the communications channel. Depending on the nature of a smart antenna system, different techniques of optimization can be used to update receive/transmit radiation patterns, automatically. The smart scanning receiver applies an adaptive algorithm to calculate complex weighting factors, which provide the analytic signal at each radiating element of the array [8]. Smart antennas can be used for signal reception as well as for the signal transmissions.
S
Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
smart antenna a set of antennas used in an intelligent way in one receiver to improve the performance of a communication link. See also beamforming, spatial diversity, spatial division multiple access. smart card credit-card-sized device containing a microcomputer, used for security-intensive functions such as debit transactions. smart material one of a class of materials and/or composite media having inherent intelligence together with self-adaptive capabilities to external stimuli applied in proportion to a sensed material response. Also called intelligent material. smart pixel an element in an array of light detectors that contains electronic signal processing circuitry in addition to the light detector; a spatial light modulator in which each pixel is controlled by a local electronic circuit. Smart pixels are fabricated with VLSI technology. Each light modulating pixel is connected to its own tiny electronic circuit adjacent to the pixel. The circuit may consist of detector, switching or logic circuit, memory, and source or additional shutter. It is an advanced, optically addressed spatial light modulator and still immature. smart sensor sensor with inherent intelligence via built-in electronics. smart structural material material in which the mechanical (elastic) properties can be modified adaptively through the application of external stimuli.
Blind Channel Identification and Source Separation in Space Division Multiple Access Systems
Published in Lal Chand Godara, Handbook of Antennas in Wireless Communications, 2018
Victor Barroso, João Xavier, José M. F. Moura
We also consider space division multiple access (SDMA) systems. These systems utilize the geographic diversity of the user’s location in a given cell at a given time interval. Suppose that the antenna of the cell base station has a fixed multibeam beam pattern. Then, for practical purposes, users illuminated by beam i do not interfere with those illuminated by beam j, even if the users in both beams transmit at the same time, and share simultaneously the same frequency band and/or the same set of orthogonal codes. In this case, a cell with a four beam antenna has its capacity increased by a factor that is ideally four. This basic idea of sectoring a cell in several spatially disjoint smaller cells based on a single-fixed multibeam base station antenna can be translated with considerable gains into a more evolved and flexible system architecture. This relies on the concept of smart antennas and gives rise to what can be denoted smart SDMA systems, as illustrated in Fig. 21.1. A smart antenna is an antenna array with a beam pattern that is controlled electronically and/or numerically so as to illuminate the desired sources and cancel out the interferences. Usually, this is done by pointing the beam into the direction of arrival (DOA) of the desired wavefront(s), while forcing deep nulls of the beam pattern at the interference DOAs. Classically, this concept of smart antenna involves well-known DOA estimation and adaptive/blind beamforming algorithms [43, 31, 20] and [11, 12, 27, 21]. In addition, we consider a different approach, which is clarified in Subsection 21.1.1, where we set up the model of the antenna array observations data. Before doing that, we introduce notation adopted in the chapter.
Antenna Array Pattern Synthesis Using Metaheuristic Algorithms: A Review
Published in IETE Technical Review, 2023
An antenna is an aerial, sensor, or transducer that transmits or receives electromagnetic waves and is an essential component of the wireless communication system. In today’s digital world, there are billions of users who are accessing the wireless services through smart phones, laptops, iPad, and other smart internet of things (IoT) devices. Most of the developed countries are focusing on establishing 5G communication network so as to provide higher bandwidth and smooth internet services to their citizens. With the exponential increase in data traffic, researchers across the world are exploring new technologies such as cognitive radios and multiple-input–multi-output (MIMO) [1] antenna to meet the requirement of the present wireless communication system. MIMO uses antenna arrays to best utilize the spectral resources of millimeter-wave technology and provides more throughput, lower latency, and spectral diversity. Smart antenna [2] uses antenna array for estimating the direction of users and thereafter directing the beam in the desired direction also known as adaptive beamforming.
A Novel Adaptive Beamforming Technology for Mobile Communication
Published in IETE Journal of Research, 2023
Rekha R. S., M. C. Parameshwara, Veerendra Dakulagi
Smart Antennas improve the signal quality, coverage, and capacity of 5G, 5GNR, and 6G and beyond by offering adaptive beamforming. This key technique of the smart antennas forms the major beam in the user direction and the nulls and sidelobes in the not-required signals’ directions. A highly directed beam ensures high directivity and optimal bandwidth which are key requirements of various wireless communication systems including radar, sonar, satellite, and mobile phones [1–6].