phd thesis in millimeter wave

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Millimeter-Wave Electronics Laboratory (MWE)

Phd dissertations.

UC San Diego

Millimeter-Wave Single- and Dual-Polarized 2x2 MIMO Phased Arrays and In-Situ Over-the-Air System-Level Self-Calibration Techniques for 5G Applications

• Nafe, Ahmed
• Advisor(s): Rebeiz, Gabriel M

This dissertation presents two millimeter-wave phased-antenna arrays at 28 GHz for fifth-generation (5G) mobile communication applications as well as techniques for performing in-situ self-test and self-calibration of single- and dual-polarized 5G phased-arrays. First, a scalable 64-element single-polarized transmit/receive phased array is built with 2x2 beamformer chips on a low-cost printed circuit board (PCB). The design emphasis is placed on minimizing the printed circuit board cost, optimizing the cross-polarization performance, and on-grid scalability. The array is capable of scanning +/-50 deg. in azimuth and +/-45deg. in elevation at 29 GHz with cross-polarization rejection better than 20 dB. It achieves an effective isotropic radiated power (EIRP) >50 dBm over a 4 GHz bandwidth from 27 to 31 GHz. Therefore, it is a suitable candidate for Gbps multi-user multiple-input multiple-output (MU-MIMO) base-station applications.

Second, a 2x64-element dual-polarized dual-beam phased array for 5G polarization MIMO is built. The phased-array has two 1:16 dual Wilkinson networks and microstrip antennas with rotated feeds for cross-polarization cancellation. The array demonstrates a measured effective isotropic radiated power (EIRP) at Psat of 52 dBm for each beam and is capable of scanning +/-50 deg.in azimuth and +/-25 deg. in elevation with >28-dB cross-polarization rejection. Simultaneous dual-beam operation is demonstrated with near-ideal patterns for each beam. The array demonstrates independent simultaneously transmitted 2x16-quadrature amplitude modulation (QAM) and 2x64- QAM data streams delivering an aggregate maximum data rate of 2x20 and 2x30 Gb/s, respectively.

Next, the problem of phased-array calibration is considered. Two calibration techniques

are developed and tested for calibrating single and dual-polarized 5G phased arrays at 28 GHz.The first technique addresses the calibration of single-polarized phased-arrays in a MU-MIMO hybrid beamforming base station system. The procedure, labeled Quad-BIST, enables built-in self-test (BIST) and self-calibration of the arrays in-situ without having to remove the array from the field. Quad-BIST relies on mutual coupling between antennas in neighboring arrays arranged in Quad-fashion to extract the calibration coefficients and perform channel characterization. Quad-BIST was successfully applied to 5G 28 GHz arrays with 4x4 and 8x8 elements in each quadrant. The results show that Quad-BIST predicts the channel states (gain and phase control) with rms errors of 0.2 dB/2 deg. and 0.4 dB/2.5 deg. for the 4x4 and 8x8 quadrants, respectively, as compared to far-field techniques. The relative channel ratios are found to be within rms errors of0.8 dB/7.5deg.. Near-ideal patterns are attained using the quadrant-level calibration for both arrays with side-lobe level’s below -20 dB over scan.

The second technique is for the calibration of dual-polarized dual-beam phased arrays. The procedure, labeled (DP-BIST), exploits the mutual coupling between different antennas of orthogonally polarized beams sharing the same aperture to enable in-situ self-calibration and self-test of the phased array channels of each beam. DP-BIST was applied to a 16-element dual-polarized dual-beam linear phased-array at 29 GHz, and predicted the relative channel states (gain and phase control) with rms errors better than 0.3 dB /3 deg. and the relative channel offsets with rms errors of 0.8 dB /6 deg. over a wide-bandwidth. These results demonstrate its feasibility for

use in 5G polarization MIMO phased arrays.

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Over-the-air characterization of millimeter-wave integrated antenna systems

• Electromagnetics

Research output : Thesis › Phd Thesis 1 (Research TU/e / Graduation TU/e)

Bibliographical note

Access to document.

• 20201111_Biggelaar Final published version, 7.4 MB

T1 - Over-the-air characterization of millimeter-wave integrated antenna systems

AU - van den Biggelaar, A.J. (Teun)

N1 - Proefschrift.

PY - 2020/11/11

Y1 - 2020/11/11

M3 - Phd Thesis 1 (Research TU/e / Graduation TU/e)

SN - 978-90-386-5125-5

PB - Technische Universiteit Eindhoven

CY - Eindhoven

Graduate Thesis Or Dissertation

Millimeter-wave gan mmic integration with additive manufacturing public deposited.

This thesis addresses the analysis, design, integration and test of microwave and millimeter-wave monolithic microwave integrated circuits (MMIC or MMICs). Recent and ongoing progress in semiconductor device fabrication and MMIC processing technology has pushed the upper limit in MMIC frequencies from millimeter-wave (30 - 300 GHz) to terahertz (300 - 3000 GHz). MMIC components operating at these frequencies will be used to improve the sensitivity and performance of radiometers, receivers for communication systems, passive remote sensing systems, transceivers for radar instruments and radio astronomy systems. However, a serious hurdle in the utilization of these MMIC components, and a main topic presented in this thesis, is the development and reliable fabrication of practical packaging techniques.

The focus of this thesis is the investigation of first, the design and analysis of microwave and millimeter-wave GaN MMICs and second, the integration of those MMICs into usable waveguide components. The analysis, design and testing of various X-band (8-12 GHz) thru H-band (170-260 GHz) GaN MMIC power amplifier (PA or PAs), including a V-band (40-75 GHz) voltage controlled oscillator, is the majority of this work. Several PA designs utilizing high-efficiency techniques are analyzed, designed and tested. These examples include a 2 nd harmonic injection amplifier, a Class-E amplifier fabricated with a GaN-on-SiC 300 GHz f T process, and an example of the applicability of supply-modulation with a Doherty power amplifier, all operating at 10 GHz. Two H-band GaN MMIC PAs are designed, one with integrated CPW-to-waveguide transitions for integration. The analysis of PA stability is especially important for wideband, high- f T  devices and a new way of analyzing stability is explored and experimentally validated.

Last, the challenges of integrating MMICs operating at millimeter-wave frequencies are discussed and assemblies using additive and traditional manufacturing are demonstrated.

• Coffey, Michael
• Electrical, Computer and Energy Engineering (ECEE)
• Popovic, Zoya
• Filipovic, Dejan
• Campbell, Charles
• Micovic, Miroslav
• DeLisio, Michael
• University of Colorado Boulder
• semiconductor device fabrication
• microwave and millimeter-wave monolithic microwave integrated circuits (MMIC or MMICs)
• Dissertation
• In Copyright
• English [eng]

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A precision millimeter-wave measurement of the Rydberg frequency

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Modeling of dispersive millimeter-wave GaN HEMT devices for high power amplifier design

electronic devices & materials

electronics: Circuits & components

computer-aided design

scalable state-space transistor model

large-signal response

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Precoding Schemes for Millimeter Wave Massive MIMO Systems

--> Gautam, Prabhat Raj (2023) Precoding Schemes for Millimeter Wave Massive MIMO Systems. PhD thesis, University of Leeds.

In an effort to cut high cost and power consumption of radio frequency (RF) chains, millimeter wave (mmWave) multiple input multiple output (MIMO) deploys hybrid architecture in which precoding is implemented as a combination of digital precoding and analog precoding, accomplished by using a smaller number of RF chains and a network of phase shifters respectively. The mmWave MIMO, which usually suffers from blockages, needs to be supported by Reconfigurable Intelligent Surface (RIS) to make communication possible. Along with the hybrid precoding in mmWave MIMO, the passive precoding of Reconfigurable Intelligent Surface (RIS) is investigated in a downlink RIS-assisted mmWave MIMO. The hybrid precoding and passive precoding are challenged by the unit modulus constraints on the elements of analog precoding matrix and passive precoding vector. The coupling of analog and digital precoders further complicates the hybrid precoding. One of the approaches taken in proposed hybrid precoding algorithms is the use of alternating optimization in which analog precoder and digital precoder are optimized alternately keeping the other fixed. Analog precoder is determined by solving a semidefinite programming problem, and from the unconstrained least squares solution during each iteration. In another approach taken in the proposed methods, the hybrid precoding is split into separate analog and digital precoding subproblems. The analog precoding subproblems are simplified using some approximations, and solved by using iterative power method and employing a truncated singular value decomposition method in two different hybrid precoding algorithms. In the prooposed codebook-based precoder, analog precoder is constructed by choosing precoding vectors from a codebook to maximize signal-to-leakage-and-noise ratio (SLNR). The passive precoding at the RIS in a single user MIMO is designed to minimize mean square error between the transmit signal and the estimate of received signal by using an iterative algorithm that solves the joint optimization problem of precoding, passive precoding and combiner. The problem of designing energy efficient RIS is solved by maximizing energy efficiency which is a joint optimization problem involving precoder, passive precoding matrix and power allocation matrix. The proposed hybrid precoding and passive precoding algorithms deliver very good performances and prove to be computationally efficient.

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Filename: Gautam_PR_Electronic&Electrical_PhD_2023.pdf

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Fullwave simulation of millimeter wave plasma diagnostics

Millimeter wave diagostics are essentiell for fusion plasmas, since they work without plasma contact.

Both reflectometry and scattering diagnostics greatly benefit from fullwave simulation of the interaction between plasma and wave.

The fullwave code IPF-FD3D is a synthetic Doppler reflectometer on top of plasma turbulence simulations. IPF-FD3D is a 2D or 3D finite difference time domain code for cold magnetised plasmas. It is written in C, with post-processing done in python.

Possible Topics

• Improvement and extension of the existing code and application to new problems of Doppler reflectometry and other millimeter wave diagnostics.
• Development of new solvers of higher order in time and space
• Adaptation of kernels to vector computers or GPU accelerators
• Explore stability issues with X mode and large density gradients
• Scaling of scattering results with turbulence strength
• Impact of higher order scattering
• Poloidal correlation reflectometry

Prerequisites

• Physics Master
• For code development, good programming skills in C
• Knowledge of python, numpy, scipy

Carsten Lechte

Leader, Microwave Technology

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Multi-parameter illumination techniques for millimeter wave imaging

Lixiao Zhang

• Vrije Universiteit Brussel

Research output : Thesis › PhD Thesis

• Millimeter Wave Imaging

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• Millimeter waves Engineering & Materials Science 100%
• Lighting Engineering & Materials Science 80%
• Imaging techniques Engineering & Materials Science 77%
• Speckle Engineering & Materials Science 70%
• Imaging systems Engineering & Materials Science 64%
• Optics Engineering & Materials Science 20%
• Airports Engineering & Materials Science 20%
• Aviation Engineering & Materials Science 19%

Multi-parameter illumination techniques for millimeter wave imaging. / Zhang, Lixiao.

T1 - Multi-parameter illumination techniques for millimeter wave imaging

AU - Zhang, Lixiao

N2 - Millimeter wave imaging is a very promising technology for concealed weapon detection that is becoming a compulsory measure to enhance aviation security. Millimeter wave imaging has two fundamental realizations, passive and active. In indoor environments, such as the airports, active imaging has the advantage of high image contrast over passive imaging; however it suffers from coherent artifacts of glint and speckle. In this work, we study material phenomenology, component technologies, quasi-optics design, and imaging system architectures, which need to be understood for building an imaging system. We present experimental imaging systems capable of providing multi-parameter, frequency, angle and phase, illumination. Through theoretical analyses and experiments, we investigate the cause of glint and speckle (interference noise), and show how multi-parameter illumination techniques can reduce these artifacts. As far as we know, this work is the first to experimentally prove the angle and phase diversity concepts for speckle reduction in millimeter wave imaging field. We also find that processing multispectral millimeter wave images can extract extra scene features and enhance object appearance, resulting in greatly improved image quality.

AB - Millimeter wave imaging is a very promising technology for concealed weapon detection that is becoming a compulsory measure to enhance aviation security. Millimeter wave imaging has two fundamental realizations, passive and active. In indoor environments, such as the airports, active imaging has the advantage of high image contrast over passive imaging; however it suffers from coherent artifacts of glint and speckle. In this work, we study material phenomenology, component technologies, quasi-optics design, and imaging system architectures, which need to be understood for building an imaging system. We present experimental imaging systems capable of providing multi-parameter, frequency, angle and phase, illumination. Through theoretical analyses and experiments, we investigate the cause of glint and speckle (interference noise), and show how multi-parameter illumination techniques can reduce these artifacts. As far as we know, this work is the first to experimentally prove the angle and phase diversity concepts for speckle reduction in millimeter wave imaging field. We also find that processing multispectral millimeter wave images can extract extra scene features and enhance object appearance, resulting in greatly improved image quality.

KW - Millimeter Wave Imaging

M3 - PhD Thesis

CY - Brussels