W/D-Bands single-chip systems in a 0.13μm SiGe BiCMOS technology-dicke radiometer, and frequency extension module for VNAs

Recent advances in silicon-based process technologies have enabled to build low-cost and fully-integrated single-chip millimeter-wave systems with a competitive, sometimes even better, performance with respect to III-V counterparts. As a result of these developments and the increasing demand for the applications in the millimeter-wave frequency range, there is a growing research interest in the field of the design and implementation of the millimeter-wave systems in the recent years. In this thesis, we present two single-chip D-band front-end receivers for passive imaging systems and a single-chip W-band frequency extension module for VNAs, which are implemented in IHP’s 0.13μm SiGe BiCMOS technology, SG13G2, featuring HBTs with ft/fmax of 300GHz/500GHz. First, the designs, implementations, and measurement results of the sub-blocks of the radiometers, which are SPDT switch, low-noise amplifier (LNA), and power detector, are presented. Then, the implementation and experimental test results of the total power and Dicke radiometers are demonstrated. The total power radiometer has a noise equivalent temperature difference (NETD) of 0.11K, assuming an external calibration technique. In addition, the dependence of the NETD of the total power radiometer upon the gain-fluctuation is demonstrated. The NETD of the total power radiometer is 1.3K assuming a gain-fluctuation of %0.1. The front-end receiver of the total power radiometer occupies an area of 1.3 mm2. The Dicke radiometer achieves an NETD of 0.13K, for a Dicke switching of 10 kHz, and its total chip area is about 1.7 mm2. The quiescent power consumptions of the total power and Dicke radiometers are 28.5 mW and 33.8 mW, respectively. The implemented radiometers show the lowest NETD in the literature and the Dicke switching concept is employed for the first time beyond 100 GHz. Second, we present the design methodologies, implementation methods, and results of the sub-blocks of the frequency extension module, such as down-conversion mixer, frequency quadrupler, buffer amplifier, Wilkinson power divider, and dual-directional coupler. Later, the implementation, characterization and experimental test results of the single-chip frequency extension module are demonstrated. The frequency extension module has a dynamic range of about 110 dB, for an IF resolution bandwidth of 10 Hz, with an output power which varies between -4.25 dBm and -0.3 dBm over the W-band. It has an input referred 1-dB compression point of about 1.9 dBm. The directivity of the frequency extension module is better than 10 dB along the entire W-band, and its maximum value is approximately 23 dB at around 75.5 GHz. Finally, the measured s-parameters of a W-band horn-antenna, which are performed by either the designed frequency extension module and a commercial one, are compared. This study is the first demonstration of a single-chip frequency extension module in a silicon-based semiconductor technology

High-frequency silicon-germanium reconfigurable circuits for radar, communication, and radiometry applications

The objective of the proposed research is to create new reconfigurable RF and millimeter-wave circuit topologies that enable significant systems benefits. The market of RF systems has long evolved under a paradigm where once a system is built, performance cannot be changed. Companies have recognized that building flexibility into RF systems and providing mechanisms to reconfigure the RF performance can enable significant benefits, including: the ability support multiple modulation schemes and standards, the reduction of product size and overdesign, the ability to adapt to environmental conditions, the improvement in spectrum utilization, and the ability to calibrate, characterize, and monitor system performance. This work demonstrates X-band LNA designs with the ability to change the frequency of operation, improve linearity, and digitally control the tradeoff between performance and power dissipation. At W-band frequencies, a novel device configuration is developed, which significantly improves state-of-the-art silicon-based switch performance. The excellent switch performance is leveraged to address major issues in current millimeter-wave systems. A front-end built-in-self-test switch topology is developed to facilitate the characterization of millimeter-wave transceivers without expensive millimeter-wave equipment. A highly integrated Dicke radiometer is also created to enable sensitive measurements of thermal noise.Ph.D

MILLIMETER-WAVE QUADRATURE RECEIVERS FOR ATMOSPHERIC SENSING AND RADIOMETRY

The objective of this research is to investigate the design challenges of millimeter wave (mm-wave) quadrature receivers for emerging applications and develop new ideas to ad- dress these challenges. Next-generation wireless networks, satellite communications, atmospheric sensing instruments, autonomous vehicle radars, and body scanners are targeting to operate at mm-wave frequencies, and high-performance electronics are needed to enable these technologies. In this research, we investigate novel circuit topologies to improve the performance of existing mm-wave quadrature receivers, particularly for radiometry and remote sensing applications. A transformer-based front-end switch is co- designed with an LNA where the transformer acts as the input matching network of the LNA, reducing the front-end loss and system noise figure. Broadband and low-loss quadrature signal generation networks are proposed to provide highly balanced quadrature signals to reject the image frequency content. In addition, a high-efficiency frequency multiplier topology is demonstrated, achieving superior performance compared to the state-of-the-art designs. Lastly, the reliability and noise performance of on-chip noise source devices (PN junctions) in a SiGe BiCMOS platform was characterized and compared. To confirm the advantages of our ideas, the measurement and simulation results of all fabricated circuits are presented and discussed.Ph.D

Millimeter-Wave Band Pass Distributed Amplifier for Low-Cost Active Multi-Beam Antennas

Recently, there have been a great interest in the millimeter-wave (mmW) and terahertz (THz) bands due to the unique features they provide for various applications. For example, the mmW is not significantly affected by the atmospheric constraints and it can penetrate through clothing and other dielectric materials. Therefore, it is suitable for a vast range of imaging applications such as vision, safety, health, environmental studies, security and non-destructive testing. Millimeter-wave imaging systems have been conventionally used for high end applications implementing sophisticated and expensive technologies. Recent advancements in the silicon integrated and low loss material passive technologies have created a great opportunity to study the feasibility of low cost mmW imaging systems. However, there are several challenges to be addressed first. Examples are modeling of active and passive devices and their low performance, highly attenuated channel and poor signal to noise ratio in the mmW. The main objective of this thesis is to investigate and develop new technologies enabling cost-effective implementation of mmW and sub-mmW imaging systems. To achieve this goal, an integrated active Rotman lens architecture is proposed as an ultimate solution to combine the unique properties of a Rotman lens with the superiority of CMOS technology for fabrication of cost effective integrated mmW systems. However, due to the limited sensitivity of on-chip detectors in the mmW, a large number of high gain, wide-band and miniaturized mmW Low Noise Amplifiers (LNA) are required to implement the proposed integrated Rotman lens architecture. A unique solution presented in this thesis is the novel Band Pass Distributed Amplifier (BPDA) topology. In this new topology, by short circuiting the line terminations in a Conventional Distributed Amplifier (CDA), standing waves are created in its artificial transmission lines. Conventionally, standing waves are strongly avoided by carefully matching these lines to 50 Ω in order to prevent instability of the amplifier. This causes that a large portion of the signal be absorbed in these resistive terminations. In this thesis, it is shown that due to presence of highly lossy parasitics of CMOS transistor at the mmW the amplifier stability is inherently achieved. Moreover, by eliminating these lossy and noise terminations in the CDA, the amplifier gain is boosted and its noise figure is reduced. In addition, a considerable decrease in the number of elements enables low power realization of many amplifiers in a small chip area. Using the lumped element model of the transistor, the transfer function of a single stage BPDAs is derived and compared to its conventional counter part. A methodology to design a single stage BPDA to achieve all the design goals is presented. Using the presented design guidelines, amplifiers for different mmW frequencies have been designed, fabricated and tested. Using only 4 transistors, a 60 GHz amplifier is fabricated on a very small chip area of 0.105 mm2 by a low-cost 130 nm CMOS technology. A peak gain of 14.7 dB and a noise figure of 6 dB are measured for this fabricated amplifier. oreover, it is shown that by further circuit optimization, high gain amplification can be realized at frequencies above the cut-off frequency of the transistor. Simulations show 32 and 28 dB gain can be obtained by implementing only 6 transistors using this CMOS technology at 60 and 77 GHz. A 4-stage 85 GHz amplifier is also designed and fabricated and a measured gain of 10 dB at 82 GHz is achieved with a 3 dB bandwidth of 11 GHz from 80 to 91 GHz. A good agreement between the simulated and measured results verifies the accuracy of the design procedure. In addition, a multi-stage wide-band BPDA has been designed to show the ability of the proposed topology for design of wide band mmW amplifiers using the CMOS technology. Simulated gain of 20.5 dB with a considerable 3 dB bandwidth of 38 GHz from 30 to 68 GHz is achieved while the noise figure is less than 6 dB in the whole bandwidth. An amplifier figure of merit is defined in terms of gain, noise figure, chip area, band width and power consumption. The results are compared to those of the state of the art to demonstrate the advantages of the proposed circuit topology and presented design techniques. Finally, a Rotman lens is designed and optimized by choosing a very small Focal Lens Ratio (FL), and a high measured efficiency of greater than 30% is achieved while the lens dimensions are less than 6 mm. The lens is designed and implemented using a low cost Alumina substrate and conventional microstrip lines to ease its integration with the active parts of the system.1 yea

Performance assessment of W-Band radiometers: direct versus heterodyne detections

W-Band radiometers using intermediate frequency down-conversion (super-heterodyne) and direct detection are compared. Both receivers consist of two W-band low noise amplifiers and an 80-to-101 GHz filter, which conforms to the reception frequency band, in the front-end module. The back-end module of the first receiver comprises a subharmonic mixer, intermediate frequency (IF) amplification and a square-law detector. For direct detection, a W-Band detector replaces the mixer and the intermediate frequency detection stages. The performance of the whole receivers has been simulated requiring special techniques, based on data from the experimental characterization of each subsystem. In the super-heterodyne implementation a local oscillator at 27.1 GHz (with 8 dBm) with a x3 frequency multiplier is used, exhibiting an overall conversion gain around 48 dB, a noise figure around 4 dB, and an effective bandwidth over 10 GHz. In the direct detection scheme, slightly better noise performance is obtained, with a wider bandwidth, around 20 GHz, since there is no IF bandwidth limitation (~15 GHz), and even using the same 80-to-101 GHz filter, the detector can operate through the whole W-band. Moreover, W-band detector has higher sensitivity than the IF detector, increasing slightly the gain. In both cases, the receiver performance is characterized when a broadband noise input signal is applied. The radiometer characteristics have been obtained working as a total power radiometer and as a Dicke radiometer when an optical chopper is used to modulate the incoming signal. Combining this particular super-heterodyne or direct detection topologies and total power or Dicke modes of operation, four different cases are compared and discussed, achieving similar sensitivities, but better performances in terms of equivalent bandwidth and noise for the direct detection radiometer. It should be noted that this conclusion comes from a particular set of components, which we could consider as typical, but we cannot exclude other conclusions for different components, particularly for different mixers and detectors.This research was funded by the Spanish Ministry of Science and Innovation through the grant: PID2019-110610RB-C22 and by the Spanish Ministry of Economy and Competitiveness, Program CONSOLIDER-INGENIO reference CSD2010-00064, CONSOLIDER-SPATEK Network of Excellence and University of Cantabria, Industrial Doctorate reference 12.DI05.648

ANALYSIS AND DESIGN OF SILICON-BASED MILLIMETER-WAVE AMPLIFIERS

Ph.DDOCTOR OF PHILOSOPH

Millimeter and sub-millimeter wave radiometers for atmospheric remote sensing from CubeSat platforms

2018 Fall.Includes bibliographical references.To view the abstract, please see the full text of the document

High-Resolution Radiometer for Remote Sensing of Solar Flare Activity from Low Earth Orbit Satellites

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause.For this Article Withdrawal Statement, please click on: https://ojs.bilpublishing.com/index.php/jasr/article/view/621Abstract: Solar flares, intense bursts of radiation, can disrupt the atmosphere and potentially affect communication, navigation and electrical systems. A newly developed miniaturised microwave radiometer used on a space-borne platform should offer astronomers unprecedented understanding of the largest explosive phenomena in our solar system. In this paper the activity and results of the EU funded research project FLARES are presented. Objective of FLARES has been the study, analysis and design of millimetre-wave (mm-wave) system-on-chip (SoC) radiometer for space-borne detection of solar flares. The proposed approach has contributed to reduce significantly the power consumption and weight with respect to the existing instruments for the observation and study of solar flares. In particular, the proposed SoC Dicke radiometer can achieve one order of magnitude improvement in terms of resolution, so allowing the detection of solar flares with relatively low intensity, i.e. about 100 times lower than those currently detected by the existing systems, owing to space-borne operations and the microchip-level miniaturization through silicon technology under space qualification

Millimeter-wave and terahertz imaging techniques

This thesis presents the development and assessment of imaging techniques in the millimeterwave (mmW) and terahertz frequency bands. In the first part of the thesis, the development of a 94 GHz passive screener based on a total-power radiometer (TPR) with mechanical beamscanning is presented. Several images have been acquired with the TPR screener demonstrator, either in indoor and outdoor environments, serving as a testbed to acquire the know-how required to perform the research presented in the following parts of the thesis. In the second part of the thesis, a theoretical research on the performance of near-field passive screeners is described. This part stands out the tradeoff between spatial and radiometric resolutions taking into account the image distortion produced by placing the scenario in the near-field range of the radiometer array. In addition, the impact of the decorrelation effect in the image has been also studied simulating the reconstruction technique of a synthetic aperture radiometer. Guidelines to choose the proper radiometer depending on the application, the scenario, the acquisition speed and the tolerated image distortion are given in this part. In the third part of the thesis, the development of a correlation technique with optical processing applicable to millimeter-wave interferometric radiometers is described. The technique is capable of correlating wide-bandwidth signals in the optical domain with no loss of radiometric sensitivity. The theoretical development of the method as well as measurements validating the suitability to correlate radiometric signals are presented in this part. In the final part of the thesis, the frequency band of the imaging problem is increased to frequencies beyond 100 GHz, covering the THz band. In this case the research is centered in tomographic techniques that include spectral information of the samples in the reconstructed images. The tomographic algorithm can provide detection and identification of chemical compounds that present a certain spectral footprint in the THz frequency band.Postprint (published version