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Experimental Investigation of Decoupling Effect on the Nonlinearity of Power Amplifiers in transmitter array

APPLIED COMPUTATIONAL ELECTROMAGNETICS SOCIETY JOURNAL 2023年第1期38卷 7-14页

作者： Peng, Fangyun Yang, Fei Liu, Bo Chen, Xiaoming Xi An Jiao Tong Univ Sch Informat & Commun Engn Xian 710049 Peoples R China China Acad Space Technol Xian 711049 Peoples R China

In a practical compact massive multiple-input multiple-output (MIMO) transmitter array, each antenna or subarray is connected to an independent power amplifier (PA) with a modest power capacity in order to avoid the challenging demand of high-power capacity of a single PA for the whole array and to facilitate the power dissipation of the transmitter array. In this case, there is simply not enough space for an isolator between the antenna and the PA. As a result, the array mutual coupling changes the load impedances of the PAs and thus further increases the MIMO transmitter's nonlinearity. In this work, the decoupling effect on the transmitter array's linearity is investigated experimentally by using an array prototype with PAs. The mutual coupling of the array ent frequencies are injected into the PAs, and the output signal of each PA is measured via a coupler. The meaenhanced by up to 10 db.

关键词： mutual coupling nonlinearity power amplifier transmitter array

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Long-range measurement system using ultrasonic range sensor with high-power transmitter array in air

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ULTRASONICS 2017年 74卷 186-195页

作者： Kumar, Sandev Furuhashi, Hideo Aichi Inst Technol Dept Elect & Elect Engn 1247 YachigusaYakusa Cho Toyota 4700392 Japan

A long-range measurement system comprising an ultrasonic range sensor with a high-power ultrasonic transmitter array in air was investigated. The system is simple in construction and can be used under adverse conditions such as fog, rain, darkness, and smoke. However, due to ultrasonic waves are well absorbed by air molecules, the measurable range is limited to a few meters. Therefore, we developed a high-power ultrasonic transmitter array consisting of 144 transmitting elements. All elements are arranged in the form of a 12 x 12 array pattern. The sound pressure level at 5 m from the transmitter array was >30 dB higher than that of a single element. A measuring range of over 25 m was achieved using this transmitter array in conjunction with a receiver array having 32 receiving elements. The characteristics of the transmitter array and range sensor system are discussed by comparing simulation and experimental results. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Ultrasonic sensor Range image transmitter array Receiver array Pulse modulation

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Rotation-Tolerant Wireless Power Transmission Scheme with Smart Positioning for Cognitive Research on Moving Animals

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IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2024年第1期18卷 123-130页

作者： Pahlavan, Saeideh Ashtiani, Shahin Jafarabadi Univ Tehran Coll Engn Sch Elect & Comp Engn Tehran 14395515 Iran

This article presents a novel wireless power transmission scheme designed for moving loads. Specifically focused on compensating for the tilt misalignment of the receiver. By utilizing phase-shifted excitation signals from an array of transmitters, the proposed scheme effectively mitigates the impact of misalignment, locally. The application of this scheme holds particular relevance for studying the behavior of moving animals in cognitive research. The system incorporates a cage with two transmitter arrays positioned on the top and bottom sides. To smart determining the receiver's position, the proposed structure utilizes current feedback from the driving circuits and employs SVM (Support Vector Machine) classification algorithms for positioning. Furthermore, when the receiver coil is tilted, a phase shift mechanism significantly enhances the power delivered to the receiver. Additionally, the use of an overlapped transmitter array enhances rotation tolerance and improves the uniformity of the magnetic fields for moving objects. The performance of the proposed scheme is validated through extensive simulations and measurements using a fabricated prototype. Notably, the designed system achieves a power delivery of 296 mW to the load at a 90 degrees angular misalignment, compared to 1.67 mu W delivered by conventional array system.

关键词： Classification algorithm free-positioning phase shift transmitter array wireless power transfer

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Electromagnetic Modelling of a 2D Transmit array for Polar Over-the-Horizon Radar

Electromagnetic Modelling of a 2D Transmit Array for Polar O...

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International Radar Conference (RADAR)

作者： Frazer, Gordon J. Williams, Charlie G. FrazerLab Pty Ltd Adelaide SA Australia Gadzooks Pty Ltd Melbourne Vic Australia

ISBN: (纸本)9781728126609

The paper highlights results from an electromagnetic modelling study into the properties of a two-dimensional transmitter array proposed by Riddolls for over-the-horizon radar in the polar region. The modelling indicates that the total radiated power efficiency of the array is low and total radiated power is likely to be insufficient for target detection and tracking in an operational OTHR. Overall radiated power efficiency is at least 10dB less than established OTHR transmitter systems. The limited array size and the need for extreme steer from the array normal mean that there is little capacity to steer the array beams in elevation, so the array design is likely to be ineffective for clutter mitigation using elevation spatial selectivity or nulling.

关键词： HF radar transmitter array mutual coupling over-the-horizon radar polar OTHR two-dimensional array

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A Selectable Regional Charging Platform for Wireless Power Transfer 45

A Selectable Regional Charging Platform for Wireless Power T...

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45th Annual Conference of the IEEE Industrial Electronics Society (IECON)

作者： Huang, Yongcan Liu, Chunhua Liu, Senyi Xiao, Yang City Univ Hong Kong Sch Energy & Environm Hong Kong Peoples R China

ISBN: (纸本)9781728148786

This paper presents a new selectable regional charging wireless power transfer (SRC-WPT) system, which can charge multiple receivers simultaneously. Meanwhile, they are put on the charging area of the system. This SRC-WPT system employs a transmitter array for WPT, which rows are controlled by relays. Furthermore, the transmitters in each row have different frequency characteristics, which can be used as the natural switches. Thus, this SRC-WPT system can selectively activate the charging region for the receivers through the different frequencies and relays. Besides, when compared with the existing multi-to-multi WPT designs, the proposed control method of the SRC-WPT system is much more simple and reliable. Finally, a model is built to verify the performances of the proposed system and the corresponding control method.

关键词： Selectable regional charging wireless power transfer transmitter array multi-to-multi charging

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A 16-Element W-Band Phased-array Transceiver Chipset With Flip-Chip PCB Integrated Antennas for Multi-Gigabit Wireless Data Links

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IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2018年第7期66卷 3389-3402页

作者： Shahramian, S. Holyoak, M. J. Baeyens, Yves Bell Labs Murray Hill NJ 07974 USA

This paper describes the design and implementation of a W-band phased-array system with printed circuit board (PCB) integrated antennas in two polarizations capable of multi-gigabit spectrally efficient wireless communication. The chipset is manufactured in a 0.18-mu m SiGe BiCMOS technology with f(T)/f(MAX) of 240-/270-GHz and is flip-chipped onto a low-cost organic PCB with integrated antenna arrays. Each chip is equipped with 16-transmit/4-receive or 16-receive/4-transmit calibrated phase shifter elements and direct up-and downconverters plus a half-rate phase-locked loop. The different system tradeoffs required to establish a multi-Gb/s wireless link at millimeter waves are carefully studied. Built-in element failure detectors, power detectors, and digital interface enable factory calibration and self-test capability. Each transceiver chip operates from 1.5- and 2.5-V supplies and consumes 5.5 and 4.5 W in transmit and receive mode, respectively. The peak transmitter effective isotropic radiation power is 34 dBm in each polarization with a measured receiver noise figure of 6.5 dB at 94 GHz. At a distance of 1 m, a maximum wireless data rate of 30 Gb/s (per polarization) using 64-QAM can be achieved and at 20 m, 8 Gb/s (dual polarization) can be established using QPSK modulation.

关键词： 5G wireless die on printed circuit board (PCB) direct conversion downconverter E-band integrated antenna millimeter wave monolithic microwave integrated circuit multi-gigabit wireless link phase-locked loop (PLL) phased-array calibration QAM constellation receiver array SiGe BiCMOS transmitter array upconverter W-band wireless link analysis

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Influence of antenna configuration on mm-wave MIMO performance in a subway-like tunnel

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IET MICROWAVES ANTENNAS & PROPAGATION 2018年第15期12卷 2395-2401页

作者： Yin, Xiaoyu Zheng, Guoxin Saleem, Asad Shanghai Univ Key Lab Specialty Fibre Opt & Opt Access Networks Joint Int Res Lab Specialty Fibre Opt & Adv Commu Shanghai Inst Adv Commun & Data Sci Shanghai Peoples R China

This study investigates the channel performance of a 28GHz multiple-input-multiple-output (MIMO) system in a subway tunnel, using ray-tracing-based simulations and experimental measurements in a realistic tunnel environment. The transmitter (Tx) array was deployed at three positions, i.e. in the centre of the tunnel, close to the sidewalls and under the ceiling. The performance was significantly better in the centre and sidewall positions. Good agreement is obtained between simulation and measurement results. Furthermore, it is inferred that the MIMO channel capacity for the Tx-receiver distance of 60m is higher than that of 15m. The angular spread calculated for the 60m case is also larger than that of the 15m case.

关键词： MIMO communication transmitting antennas microwave antenna arrays tunnels ray tracing channel capacity millimetre wave antenna arrays millimetre wave communication antenna configuration mm-wave MIMO performance subway-like tunnel multiple-input-multiple-output system ray-tracing-based simulations realistic tunnel environment experimental measurements transmitter array sidewall positions MIMO channel capacity Tx-receiver frequency 28 GHz distance 60 m

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Digital beamforming antenna array with polarisation multiplexing for mobile highspeed satellite terminals at Ka-band

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JOURNAL OF ENGINEERING-JOE 2016年第6期2016卷 180-188页

作者： Rohrdantz, Benjamin Kuhlmann, Karsten Stark, Alexander Geise, Alexander Jacob, Arne F. Tech Univ Hamburg Inst Hochfrequenztech D-21073 Hamburg Germany PTB Hochfrequenzmesstech D-38116 Braunschweig Germany OHB Syst AG D-28359 Bremen Germany Airbus Def & Space GmbH Compact Range & Test Serv D-82024 Taufkirchen Germany

In this contribution, a planar antenna array terminal for mobile satellite communications at Ka-band is proposed. This Earth station on mobile platform uses separate transmit and receive apertures to obtain a flat design well suited for aeronautical applications. Digital beam-forming is applied for fast beam scanning, tracking, and enhanced post-processing capabilities. The active antenna elements exhibit dual polarisation to comply with a four-colour spot beam arrangement commonly used by high-throughput satellites. Advanced frontend packaging concepts for a high integration density enable half wavelength element spacing. This prevents grating lobes and yields a large scanning range. A modular approach allows to flexibly adapt the array size to the application specific needs. An 8 x 8 receiver (Rx) array at 20 GHz and a 16 x 3 transmitter array at 30 GHz are demonstrated. The measured results obtained in conjunction with inter-element decoupling validate the approach. The principal suitability of the Rx array for the intended application is tested in a field experiment.

关键词： array signal processing mobile radio satellite communication planar antenna arrays inter-element decoupling transmitter array receiver array large scanning range grating lobes advanced frontend packaging frequency 30 GHz frequency 20 GHz digital beamforming antenna array polarisation multiplexing mobile high-speed satellite terminals Ka-band planar antenna array terminal mobile satellite communications Earth station mobile platform aeronautical applications beam scanning post-processing capabilities dual polarisation four-colour spot beam high-throughput satellites

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500 GHz Sensor System in SiGe for Gas Spectroscopy 40

500 GHz Sensor System in SiGe for Gas Spectroscopy

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40th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)

作者： Schmalz, K. Neumaier, P. Wang, R. Borngraeber, J. Debski, W. Kaynak, M. Kissinger, D. Huebers, H. -W. IHP D-15236 Frankfurt Oder Germany Deutsch Zentrum Luft & Raumfahrt DLR D-12489 Berlin Germany Silicon Radar D-15236 Frankfurt Oder Germany Humboldt Univ D-12489 Berlin Germany

ISBN: (纸本)9781479982721

A 500 GHz sensor system for gas spectroscopy is presented, which includes a SiGe transmitter (TX) array and a SiGe receiver (RX). The integrated local oscillators of the TX-array and RX chips are controlled by two external phase-locked loops (PLL). The reference frequency of the TX-array PLL is modulated for 2f absorption spectroscopy (second harmonic detection). The performance of the sensor system is demonstrated by detecting the 2f absorption spectra of methanol and acetonitrile.

关键词： Ge-Si alloys gas sensors organic compounds radio transceivers semiconductor materials submillimetre wave spectroscopy 2f absorption spectroscopy RX chips SiGe TX array acetonitrile external phase-locked loops frequency 500 GHz gas spectroscopy integrated local oscillators methanol receiver reference frequency second harmonic detection sensor system transmitter array Absorption arrays Frequency modulation Phase locked loops Sensor systems Silicon germanium Spectroscopy

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Effects of mobile rotational movements in wireless propagation channels

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IET COMMUNICATIONS 2008年第9期2卷 1109-1117页

作者： Rad, H. Saligheh Gazor, S. Harvard Univ Sch Engn & Appl Sci Cambridge MA 02138 USA Queens Univ Dept Elect & Comp Engn Kingston ON K7L 3N6 Canada

The impact of non-straight movements of a mobile station ( MS), for example rotation of the MS, on the statistics of a wireless propagation channel needs to be studied in the modern literature of wireless channel modelling. The authors formulate the effects of MS rotation on a cross-correlation model for a multiple-input multiple-output Rayleigh fading channel in a two-dimensional (2D) multipath propagation medium. The authors consider communication over a non-isotropic wave propagation environment employing directional antenna propagation patterns (APPs) at both transmitter and receiver arrays. The cross-correlation function (CCF) is computed when the MS rotates with a constant angular velocity and moves with a constant linear speed on the 2D plane. It is shown that the angular movement of the MS results in a cyclostationary channel process. In such a situation, the authors analyse the derived CCF using the continuous-time Fourier series in terms of the MS angular velocity, the parameters of the propagation environment and the employed antennas. The numerical evaluation shows that the energy dispersion in different frequencies is significantly influenced by the type of the directional APP, the distribution of scatterers and the angular Doppler shift. Furthermore, the authors establish an approximate relationship between the coherence-time and the MS angular velocity using a numerical curve fitting.

关键词： mobile station directional antenna propagation patterns cross-correlation function MIMO systems wireless channels directive antennas multiple-input multiple-output Rayleigh fading channel electromagnetic wave propagation angular Doppler shift continuous-time Fourier series multipath channels cyclostationary channel process wireless channel modelling energy dispersion angular velocity transmitter array cross-correlation model Rayleigh channels multipath propagation medium curve fitting nonstraight movements wireless propagation channels receiver array mobile rotational movements Doppler shift angular movement numerical curve fitting antenna radiation patterns non-isotropic wave propagation environment linear speed

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