PRISM :: Browsing by Author "Belostotski, Leonid"

Browsing by Author "Belostotski, Leonid"

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Open Access
10-Gb/s 0.13-um CMOS Inductorless Modified-RGC Transimpedance Amplifier
(IEEE, 2015-07-17) Taghavi, Mohammad Hossein; Belostotski, Leonid; Haslett, James W.; Ahmadi, Peyman
This paper presents an inductorless 0.13-um CMOS TIA structure that is a modified version of a regulated cascode (RGC) TIA. An immittance converter is incorporated to reduce power consumption while increasing ransimpedance gain. Measured 3-dB bandwidth is 7 GHz, sufficient for 10-Gb/s operation, in the presence of 250 fF capacitance at the TIA input, representative of typical CMOS photodiode capacitance. The transimpedance gain of the single-stage TIA is 50 dB, and the group-delay variation is less than ±19 ps over the 3-dB bandwidth. The circuit occupies an active area of 180um x 90um and consumes 7 mW from a 1.5-V supply. The measured average input-referred current noise of the TIA is 31 pA/sqrt(Hz). Simulations and analysis show that the proposed single-stage TIA architecture is capable of achieving improvement in the transimpedance limit over a single-stage RGC TIA designed for the same data rate and the same input photodiode capacitance. A comparison of measurement results to published TIAs also demonstrates the competitive performance of the proposed TIA in terms of the TIA transimpendance gain, bandwidth, area, and power consumption.
Open Access
300-1500 MHz Broadband LNA for the Canadian Hydrogen Observatory and Radio-transient Detector
(2022-09) Lai, Carlson; Belostotski, Leonid; Nielsen, Jorgen; Abou-Zeid, Hatem
A next generation radio telescope, CHORD is currently being designed and prototyped. This new radio telescope is designed to supersede the CHIME telescope in area, noise and bandwidth. The specifications for this telescope require a bandwidth between 300 MHz to 1500 MHz, along with the lowest possible noise figure at room temperature. To achieve this, a new LNA topology is proposed using a capacitively loaded source degenerated amplifier with a matching network. This topology allows the designer to control the optimum source impedance for low noise independently from the input impedance, such that the two can be conjugates of each other. A matching network is then proposed to approximate the optimum source impedance for broadband power and noise matching. The LNA was designed and measured, with S11 below -8 dB between 320 MHz to 1580 MHz, S21 of 32 dB +/- 1.2 dB, IP1dB greater than -37 dBm, and IIP3 greater than -20 dBm. Noise parameters were measured, with the LNA achieving sub-20 K noise temperatures between 500 MHz to 1400 MHz.
Open Access
400-to-800MHz Low-Noise Amplifier for Radio Astronomy
(2018-04-25) Kulatunga, Thisara; Belostotski, Leonid; Haslett, James; Nielsen, Jorgen; Landecker, Thomas; Belostotski, Leonid; Haslett, James
The Dominion Radio Astrophysical Observatory is interested in investigating the possibility of replacing 408 MHz narrow-band feed antennas with wide-band antennas. Such change would require low-noise amplifiers (LNAs), which would operate over a wider frequency band. This thesis explores the feasibility of using GaAs p-HEMT transistors to implement a wide-band low-noise amplifier for the 400 MHz to 800 MHz frequencies for use in a wide-band antenna array. In order to demonstrate the feasibility, a three-stage cascaded low-noise amplifier was developed and experimentally verified. The GaAs p-HEMT LNA achieves a sub 0.36dB noise figure in the 390MHz to 810MHz frequency region and a beam-equivalent receiver noise temperature of 17.8K to 28.3K within the 390 MHz-to-810MHz frequency region. The LNA demonstrates S21 > 41.1 dB within the 400 MHz-to-800MHz frequency region while consuming 406mW of power. This LNA has P1dB> -32.9 dBm and IIP3 > -22.5 dBm within the frequency region.
Open Access
A 460 GHz CMOS Substrate-Integrated-Waveguide Slot Antenna
(2015-09-25) Xie, Hao; Belostotski, Leonid; Okoniewski, Michal
The design of the Cerro Chajnantor Atacama Telescope (CCAT) is progressing within the international astronomical community. This thesis examines the feasibility of using CMOS technology to implement a 460 GHz SIW slot antenna for the CCAT Heterodyne Array Instrument. A 46 GHz broadband high-gain SIW slot antenna was designed and tested to verify the SIW slot antenna design procedure. That design demonstrated good agreement between the simulated and measured results. The antenna has a measured gain of 7.8 dBi at 46.2 GHz and bandwidth of 4.72 GHz. Then design of a 460 GHz SIW antenna was conducted in a 65 nm CMOS process. Several methods were used to simplify the design and simulations: an inductor identification layer was introduced to minimize the design-rule restrictions, and an equivalent dielectric layer was calculated to reduce the computational resource for 3D electromagnetic simulations. The proposed antenna has a gain of 0.09 dBi, efficiency of 29.1% and bandwidth of 25.3 GHz.
Open Access
A Broadband Variable-Gain Amplifier and a Broadband Self-Calibrated High-Sensitivity Power Detector for the Square Kilometre Array
(2014-12-03) Wu, Ge; Belostotski, Leonid; Haslett, James W.
The Square Kilometre Array (SKA) is an international project to design and construct the next generation ultra-sensitive radio telescope. Depending on the final configuration, the SKA will require millions of receivers ideally fabricated in a low cost semiconductor process. This thesis presents a study of using CMOS technologies, which are themost common and less expensive semiconductor option, to implement a variable gain amplifier (VGA) with a linear-in-dB performance and an RMS power detector (PD) for a mid-frequency SKA receiver. Two linear-in-dB VGAs were designed and experimentally verified in this work. The first VGA meets most of the SKA specifications except bandwidth and linear-in-dB range. The second VGA uses a bandwidth extension technique and a low threshold voltage transistor to achieve a maximum tunable gain range of 34 dB and the linear-in-dB range of 28.5 dB within ±1 dB error, an upper 3 dB cutoff frequency of 2.1 GHz and a power consumption of 1.1mW. Both S11 and S22 are less than -10 dB from 100 MHz up to 4.2 GHz. This VGA achieved the lowest power consumption among comparable VGAs published to date. A differential broadband self-calibrated RMS PD using the MOSFET square-law characteristics was proposed and experimentally verified in this work. After automatically compensating mismatches between all circuit components by adjusting input transistor bulk voltage, the proposed PD circuit showed the highest sensitivity and lowest power consumption of all PDs published prior to this work. The PD operates over an input power range from -48 dBm to -11 dBm with output voltage offset less than 0.95 dB for the SKA midfrequency range with an input-referred P1dB of -11 dBm, 3 dB bandwidth of 1.8 GHz and power consumption of only 1.2 mW. This PD meets all requirements of the mid-frequency SKA receiver. This power detector was embedded within the receiver and fabricated in a TSMC 65nm CMOS process. Measurement results showed an input power range from -40 dBm to -20 dBm with power consumption of 1.5mW.
Open Access
A CMOS Optical Receiver for the Square Kilometer Array Radio Telescope
(2015-06-19) Taghavi, Mohammad Hossein; Belostotski, Leonid
The Square Kilometer Array (SKA) is an international effort to construct the world 's largest radio telescope with an effective area of one square kilometer. By their nature signals arriving from astronomical sources are very weak. An SKA receiver therefore will require a wideband high-frequency gain in the order of 70 dB to condition the signals for data processing. This large wideband gain makes the conventional data transfer through coaxial cables problematic as any amount of signal leaking back into the receiver front-end can either overpower the desired signals and desensitize the receiver and/or cause stability issues. Therefore, optical data transfer is desirable and is being considered in this thesis. This thesis presents a study of using CMOS technologies, which are attractive due to their lower costs, higher integration densities, and lower power consumption, to implement an optical transfer for an SKA receiver. Four different transimpedance amplifiers (TIAs) were designed and experimentally verified in this work. One of these TIAs that employs an immittance converter, which provides both a negative input resistance to increase the input pole frequency and a negative inductance to improve the circuit stability, was chosen as an optical receiver front end. The proposed TIA achieves a 6 GHz 3-dB bandwidth with a 250 fF photodiode capacitance. The transimpedance gain of a single-stage TIA is 54 dBohm, the group-delay variation and average input-referred noise current are 6 ps and 24 pA/sqrt(Hz), respectively, over its entire bandwidth. A fully integrated CMOS optical receiver front end was proposed and experimentally verified in this work. The receiver achieves a transimpedance gain of 77.7 dBohm with a 12-GHz 3-dB bandwidth. With a photodiode, whose responsivity is 0.8 A/W, the simulated sensitivity of the optical receiver at 15 Gb/s is about -12 dBm for a bit error rate (BER) of less than 10^{-12}. A time-to-digital (TDC) converter that utilizes an optimum detection concept was designed and fabricated in a TSMC 65nm CMOS process as an optical receiver back end.
Open Access
A Computer-Aided Design Assistant Tool for Elementary Linear Circuit Topologies
(2012-12-06) Shahhosseini, Delaram; Belostotski, Leonid; Behjat, Laleh
In this thesis, a CAD tool called analog design assistant (ADA), is developed to help analog circuit designers find new circuit topologies. First, a methodology to automatically generate all analog circuit topologies containing two or three transistors is developed. For each topology, circuit characteristics, such as DC voltage gain, are calculated. The DC voltage gain of each generated circuit is maximized by formulating and solving an optimization problem. After solving the optimization problem, it is shown that over 5,000 out of 56,000 circuits can achieve a DC voltage gain higher than 1. All generated circuit topologies and corresponding characteristics are stored in a database. A GUI is developed to help analog circuit designers search the database and find new topologies. In order to demonstrate the capability of ADA in generating new topologies, a previously unknown high-gain amplifier is selected, and designed in a 0.13-um standard CMOS technology.
Open Access
A Liquid Crystal-Switched Passive Van Atta Array Element for Millimetre-Wave Automobile Radar Target Enhancement and Concurrent Data Modulation in Adverse Weather Conditions
(2017) Dratnal, Anthony Jan; Okoniewski, Michal; Nielsen, Jorgen; Belostotski, Leonid; Messier, Geoffrey
Severe weather challenges drivers by degrading visibility and road conditions. Modern automotive collision avoidance systems also experience degraded performance in bad weather, which reduces the range of car-mounted sensors that detect obstacles on the road, and of communication networks that warn other cars about hazards. Radar systems are resistant to most weather but remain affected by heavy rainfall, due to regulatory constraints on frequency and power. Radar architectures can improve, but this thesis proposes to enhance the detectability of vehicles by increasing their radar cross sections with a new automotive safety device: a conformal retrodirective patch antenna array installed into car bodywork. A millimetre-wave array element with a novel liquid crystal switch is successfully simulated, fabricated, and experimentally shown to sufficiently modulate the retransmitted radar signal to piggyback data. This guarantees safe detection ranges in worst-case rain showers and replaces secondary communication systems, minimizing environmental RF pollution.
Open Access
A Noise-Matched Voltage Controlled Oscillator for Quantum Computing
(2024-08-20) Wong, Gregory; Belostotski, Leonid; Nielsen, Jorgen; Dankers, Arne
The advent of complex optimization problems such as drug synthesis, economic forecasting and cryptography has led to a need for increased computational speeds. Quantum computing offers exponentially faster computation than is capable by current state of the art computers. However, the information they process is extremely susceptible to noise and they require cryogenic environments to function. This necessitates that any electronics required to interface with them must be low noise, to preserve the information of these computers, and low power, to enable them to operate within a cryogenic environment. Voltage controlled oscillators (VCO) are of particular importance as they generate radio-frequency pulses that manipulate the operations of quantum computers. This thesis proposes a noise-matching topology for VCOs that utilizes impedance networks to limit phase noise at the oscillation frequency. Theoretical equations based on small-signal circuit models and impulse sensitivity functions were derived to demonstrate the feasibility and to guide the design procedure. The circuit parameters were then determined using numerical calculations in MATLAB and the optimization tool in Cadence. Two sets of VCOs were fabricated in GlobalFoundries 22nm technology to verify the findings. Tests were conducted in a cryostat at 295K, 200K, 70K and 20K. An 8GHz VCO was built which achieved -134.6dBc/Hz of phase noise at 10MHz offset at 20K while consuming 0.373mW. A 5.5-9GHz tunable VCO was also demonstrated which achieved a best phase noise of -136.2dBc/Hz at 10MHz offset at 20K with 0.678mW of power. Overall, this thesis demonstrates a first step towards building a low noise and low power VCO suitable for quantum computing with the noise matching topology and less than 1mW of power consumption.
Open Access
An Active-Loaded Phase-Conjugating Rotman Lens for Intelligent Transportation System Backscattering Applications
(2018-12-10) Keshavarzian, Pouyan; Okoniewski, Michal M.; Nielsen, Jorgen; Fear, Elise C.; Belostotski, Leonid; Knight, A. M.
Retro-directive backscattering is useful for improving link-budget in communication systems, localization and radar cross-section enhancement. Many existing technologies have limitations in terms of overall gain and scalability to higher frequencies. This thesis presents a new active retro-directive array architecture for Intelligent Transportation System applications such as automotive radar. The topology involves designing a phase-conjugating Rotman lens with reflection amplifiers for increased gain. Components of this architecture can be scaled to mm-wave. A reflection amplifier is prototyped and tested to have a maximum gain of 17.1 dB at 5.3 GHz. The circuit is then augmented onto a phase-conjugating Rotman lens. The amplifiers are tuned to ~ 6.5 dB gain at 5.15 GHz and the overall phase-conjugating performance is assessed. The active eleven element lens has a calculated backscattering gain of 19.2-25.4 dB across the scanning range of ±32 ˚ . Keywords: rotman lens, retro-directivity, phase-conjugation, ITS
Open Access
Advanced Delta-Sigma Transmitter Architectures for High Performance Wireless Applications
(2017) Jouzdani, Maryam; Ghannouchi, Fadhel M.; Helaoui, Mohamed; Belostotski, Leonid; Fear, Elise; Baudoin, Geneviève; Nowicki, Edwin
To satisfy the wireless market’s growing demand for higher data rates services and to maximize the bandwidth spectral efficiency, modern modulation schemes have been developed. Transmitting spectrally efficient non-constant envelope signals modulated by modern schemes necessitates designing highly linear and efficient transmitter systems for reaching the signal-to-noise ratio (SNDR) requirements and longer battery life. Delta-sigma modulator (DSM) based transmitters have the potential of good linearity performance and re-configurability for multi-standard applications. They also enable the use of high efficiency switching power amplifiers (PAs). This thesis was dedicated to enhancing the performance of DSM based transmitters. The first part of the thesis will focus on the design and evaluation of a novel high-pass (HP) DSM- based digital-IF transmitter architecture to address the in-band quantization noise problem and low coding efficiency in Cartesian HP and band-pass (BP) counterparts. As the most power consuming part of the transmitters, the design of highly efficient RF PAs has been the subject of several studies with different techniques being proposed to overcome this challenge. Dynamic control of the load impedance of the amplifier is a promising technique used in pulsed load modulation (PLM) PAs. Digital load modulation is realized in PLM PAs with the aid of the envelope delta-sigma modulator (EDSM) to enhance the efficiency in larger power back-off region while preserving the quality of the signal. The design and fabrication of a PLM PA with gate bias modulation for high power applications is the subject of the second part of this thesis. Employing the designed PLM PA, a digital DSM-based transmitter topology was realised for base-band applications. The transmitter was successfully tested with standard signals showing promising results. In the next step, it is shown that to further increase the efficiency of the PLM PA-based transmitters, it is possible to reduce the delta-sigma quantization noise and thus, the quality of the encoded signal by replacing the EDSM by a complex delta sigma modulator (CDSM). Based on this method, a novel transmitter architecture is proposed which benefits from CDSMs and PLM PAs for reaching the SNDR requirements and high efficiency performance at the same time.
Open Access
Advanced Doherty Transmitter Architectures for Wireless Communication Systems
(2021-02-02) Zhao, Yulong; Ghannouchi, Fadhel M.; Helaoui, Mohamed; Belostotski, Leonid; Okoniewski, Michal M.
Power amplifier (PA) is a critical and energy-consuming building block in wireless communication transmitters. Base stations need to be efficient to minimize the electricity consumption. The wasted energy in wireless transmitters is converted to heat, which degrades the reliability of the system. Over the years, many efficiency enhanced PA architectures have been developed. Due to its good performance and simple structure, the Doherty PA (DPA) has been widely used in base station applications. However, conventional DPA focuses on the design of the amplifier module itself and the needed quarter wavelength transmission line limits the bandwidth of the DPA. In this thesis, first, the high efficiency Doherty transmitter based on the array antenna is proposed and its dynamic load modulation scheme is investigated. The design equations are derived based on the impedance matrix of the generalized load modulation network. The antenna array is then proposed and optimized to achieve the required impedance matrix. The measured results show good performances, which successfully verify the proposed theory and design equations. Second, the dual-branch dynamic reverse load modulation (RMDB) PA is analyzed. Different from the conventional DPA, the carrier PA is a current biased transistor and the peaking amplifier is a voltage biased transistor in the RMDB PA. The working principle of the dynamic load modulation is thoroughly analyzed. To verify the design theory, a Monolithic Microwave Integrated Circuit (MMIC) PA is designed and fabricated using the United Monolithic Semiconductors GH25 process. It is also the first reported MMIC that covers both 4th generation and 5th generation wireless communication frequency bands. Third, to further increase the efficiency of the RMDB PA, the harmonic control technique is implemented in a second MMIC PA design. The constraints of implementing harmonic control in RMDB MMIC PA are thoroughly discussed. By introducing extra offset lines in the carrier and peaking amplifier branches, the second harmonic control was successfully realized. Finally, optimal fundamental load modulation design space for Class-X harmonically tuned power amplifiers (PAs) was studied. Optimal fundamental load trajectories with different sets of second and third harmonic impedances are calculated and verified with harmonic load-pull measurement.
Open Access
Antenna-Array Network Model
(IEEE, 2020-03) De Silva, Supun; Okoniewski, Michal; Belostotski, Leonid
An antenna can be modeled as a two-port network using S-parameters. However, having individual antenna S-parameters is not sufficient for modeling an array of antennas as antennas exhibit mutual coupling. This article proposes a network model to represent an antenna array with mutual coupling. Using the proposed model, an N-element antenna array is modeled as a combination of two-port networks representing each element and an N-port network representing mutual coupling. Two techniques to calculate mutual coupling S-parameters are presented: a primary method using numerical solutions and an approximate method using approximate expressions. The proposed model was validated using four monopole arrays having different inter-element spacings, the number of elements, and non-identical antennas.
Open Access
Arrays of Superconducting Resonators Exhibiting Kinetic Inductance for Parametric Amplification at Cryogenic Temperatures
(2024-01-25) Tabesh, Alireza; Belostotski, Leonid; Barzanjeh, Shabir; Belostotski, Leonid; Barzanjeh, Shabir; Nielsen, Jorgen S.; Janitz, Erika
Over the past decade, numerous reputable companies, including IBM, Google, Microsoft, and various startups, have invested substantial resources in industrial research on quantum computing and the development of quantum computers. These quantum computers rely on qubits, or quantum bits, as their fundamental components, with information transmission facilitated by low-power microwave fields. Consequently, achieving ultra-low-noise microwave amplification is of paramount importance for accurately measuring these microwave fields and determining qubit state information. Parametric amplification emerges as a highly effective technique for conducting precise microwave measurements on quantum circuits. Parametric amplification, featuring Josephson Junctions, has been a well-established method for some time. However, recent advancements have introduced kinetic inductance as a non-linear superconducting phenomenon, leading to improved parametric amplifier designs. This thesis delves into a study of superconducting resonators, which serve as the core component of kinetic-inductance parametric amplifiers.
Open Access
Automated Noise-Parameter Measurements of Cryogenic LNAs
(IEEE, 2021-06-25) Sheldon, Alexander; Belostotski, Leonid; Mani, Hamdi; Groppi, Christopher E.; Warnick, Karl F.
This paper addresses the need for measured cryogenic noise parameters. The measurement process is discussed and an analysis of the measurement uncertainty is performed. To verify proper operation of the measurement system, measurements of a 1-to-2-GHz radio-astronomy low-noise amplifier (LNA) at 20, 75, and 296 K are presented. In these measurements, the typical 1$\sigma$ measurement uncertainty in noise temperatures and minimum noise temperatures is < 10%.
Open Access
Channel Characteristics and Receiver Performance Analysis of Mud Pulse Telemetry System
(2019-08-02) Nath, Santosh; Messier, Geoffrey G.; Belostotski, Leonid; Shor, Roman J.; Nielsen, Jorgen
Improving the data rate has been a major challenge in mud pulse telemetry. One of the reasons for the confinement in lower data rate is due to the lack of knowledge of the mud communication channel. Furthermore, the mud property, drill string geometry, interferers from the mud pumps and noise affect the pressure wave propagation. This thesis provides a novel mathematical characterization of a mud communication channel and uses several signal processing techniques to enhance the performance of a mud pulse receiver. By introducing a fluid transmission line model, the attenuation of the pressure wave is characterised and is verified with the experimental results found in the literature. Based on this model, a transfer function of the mud communication channel including the effect of reflections from the multiple junctions has been derived. Finally, the receiver performance is evaluated by cancelling out the narrow-band interferers and equalizing the mud channel.
Open Access
Characterizing Star Forming Clumps in the Galaxy: A Comparison of JCMT and Herschel Observations
(2018-08-23) Tahani, Kianoosh; Plume, René; Jackel, Brian J.; Moazzen-Ahmadi, N.; Belostotski, Leonid; Naylor, David A.
We present the first comparison between the Herschel Infrared Galactic plane survey (Hi-GAL) at 500 µm and the James Clerk Maxwell Telescope (JCMT) Plane Survey (JPS) using SCUBA-2 at 450 µm. The JCMT data were taken as a part of a follow up project for the JPS - circular regions with a radius of ∼ 0.8◦ at ` = 10◦ & ` = 30◦ . Given the higher resolution of the JPS 450 µm observations we were able to determine the number of clumps identified in the Hi-GAL 500 µm data (PLW), that are actually composed of multiple, smaller clumps (i.e. the fragmentation). At ` = 10◦ , we find that 35% of the PLW clumps fragment into smaller pieces and at ` = 30◦ this multiplicity number is 23%. While there is no apparent correlation with the radius or mass of the PLW clumps, there are weak trends with flux and density. PLW clumps with densities greater than 104 cm−3 seem to always fragment into smaller clumps, and PLW clumps with integrated flux greater than 50 Jy, have a 50% chance of fragmenting (and all PLW clumps with an integrated flux of > 200 Jy fragment). Pixel-by-pixel and clump-by-clump comparisons between the PLW 500 µm and JPS 450 µm datasets reveal good agreement in the flux levels for compact bright regions suggesting that the JPS calibration at 450 µm is good. The amount of missing flux in the JPS 450 µm data at different spatial scales is investigated quantitatively via a power spectrum analysis and suggests that observations with SCUBA-2 are, in general, able to fully recover the flux for structures with sizes smaller than ∼ 1 arcmin. Moreover, we present the results of our SED fitting to the combined datasets by extracting the clumps from five Hi-GAL bands, two JPS bands, and counterpart data at ∼20 µm. We determine the current physical conditions (i.e. temperature, luminosity, mass, density, etc.) of the star forming clumps in these Galactic coordinates. Our work identifies that 30 of these clumps had a Class 0 characteristics and 52 of them are compatible with Class I or II stars. We investigate how SFE calculated for the monolithic Hi-GAL clumps changes when the multiplicity fraction is incorporated. The average SFE is observed to increase from 8% to 13% once the clump multiplicity was taken into account. Our simulations suggest that the low SFE in the most massive clumps is most likely due to the formation of massive stars. We then determine the SFE and investigate differences/similarities in these two galactic longitudes. The average SFE at ` = 10◦ is 16% while at ` = 30◦ the average SFE is 9%. We propose that the turbulence at ` = 30◦ is supporting this region against gravitational collapse, which potentially results in formation of more massive cores/stars and therefore lower SFE.
Open Access
CMOS Laser Diode Drivers for Supercontinuum Generation
(2016) He, Yuting; Yadid-Pecht, Orly; Barclay, Paul; Belostotski, Leonid
There have been intense research efforts on developing compact and low-cost supercontinuum generation (SCG) systems, which have various application areas including telecommunications, spectroscopy, and optical coherence tomography. This research employs complementary metal–oxide–semiconductor (CMOS) technology to design and implement two integrated laser diode drivers for reducing the size and cost of SCG systems. A continuous-wave CMOS driver with a maximum output current of 600 mA is developed for driving a laser diode in an erbium-doped fiber amplifier (EDFA). A picosecond pulsed CMOS driver is designed and applied for gain-switching a laser diode to produce optical pulses with a pulse width of 200 ps and a repetition rate of 5.6 MHz. The gain-switched laser diode output is amplified by an EDFA and then launched into a highly nonlinear fiber for SCG. The generated supercontinuum has an average power of 62 mW and a spectral bandwidth of 806 nm.
Open Access
CMOS Parametric Receiver Design for Short-Range and High Data-Rate Wireless Communication
(2021-02-03) Zhao, Zhixing; Magierowski, Sebastian; Belostotski, Leonid; Okoniewski, Michal; Helaoui, Mohamed; Barzanjeh, Shabir; Saavedra, Carlos
With the advent of 5G era, millimeter-wave technologies are drawing increased attention for fast-data-rate communication. Massive RF nodes deployments in 5G require inexpensive RF solutions. Recent RF developments associated with CMOS technologies promise to fulfill such requirements. However, millimeter-wave circuitry on CMOS is still expensive because achieving sufficient power gain requires advanced and costly CMOS nodes. In addition, the conventional way of seeking performance improvements, i.e. reliance on Moore’s law, is approaching its physical limits. In this thesis, parametric circuitry, as an alternative to RF performance enhancement at less-advanced nodes, is investigated. The parametric circuitry exploits varying capacitance to channel RF signal power from one frequency to another. During this frequency translation, an oscillator signal (known as Pump) power is added to the RF signal of interest so that the power gain is realized. The method is unlike a conventional transistor-based amplifier, which is essentially a DC-to-AC power converter. In addition to frequencies, the power gain of the parametric circuit can be tuned by the Pump signal as well. In this thesis, firstly the key technology, i.e. a variable capacitor, on CMOS technology is introduced and discussed. Then, the linearity of a CMOS 1-to-36 GHz parametric upconverter is analyzed. The agreement of the measurement and simulation results with the outcome of the analytic analysis demonstrates that the proposed harmonic analysis method can be relied on for the first-order analysis and quick grasp of design insights. Later, a sub-6GHz parametric downconverter is presented with a power gain of 24 dB. This circuit design shows a promising means to deploy parametric circuits at low-frequency bands.
Open Access
A Completely Integrated Warm-IF Receiver and a 10GS/s Analog-Delay Pipeline ADC for Radio-Telescope Applications
(2019-05-22) Zailer, Eugene; Belostotski, Leonid; Plume, René; Helaoui, Mohamed; Vyas, Rushi J.; Brown, Jo C.; Saavedra, Carlos E.
The Cerro Chajnantor Atacama Telescope (CCAT) Heterodyne Array Instrument (CHAI) radio-telescope is a large international effort involving University of Calgary, Kölner Observatorium für Sub-Millimeter Astronomie (KOSMA), University of Bonn, McGill University, and many others. The goal of the CHAI project is to upgrade the existing telescope capabilities to receive high-resolution images specifically in the 460 GHz and 830 GHz bands. The intended receiver system will have 128 (up to 256) antenna elements each requiring 128 independent receivers to be used. The Square Kilometer Array (SKA) is another major global effort to create the most sensitive radio telescope ever attempted. This radio telescope involves more than a hundred universities as well as industry. The SKA will potentially require millions of antenna elements, each requiring a cost-effective receiver to be implemented. This thesis presents a study of using a cost-effective CMOS technology to implement a complete receiver integrated on a single chip for CHAI and SKA telescopes. A receiver including a low-noise amplifier (LNA), a voltage-controlled oscillator (VCO), a mixer, and a variable-gain amplifier (VGA), based on CHAI design requirements, was implemented in 0.13 μm complementary metal-oxide semiconductor (CMOS) technology. An analog-to-digital converter (ADC) was implemented, based on the design requirements of the SKA, in 65 nm CMOS technology. A novel method for LNA wide-band noise optimization is developed and implemented in 0.13 μm CMOS technology. The design of the LNA is verified experimentally and meets the design requirements set by the CCAT project specifications. The LNA achieves a noise figure (NF) of <2.4 dB over the intended band of 4 GHz to 8 GHz with a gain of 18 dB. A novel method for VCO phase-noise (PN) optimization that simultaneously reduces VCO die-area and increases the available tuning range, was developed. The VCO is implemented in 0.13 μm CMOS technology and the novel optimization method is verified experimentally. The measured PN at 8 GHz is -134.3 dBc/Hz at a 1 MHz offset with a figure-of-merit (FOM) of 204 dBc/Hz. The ADC is developed using a novel topology that improves the speed performance of sub-ranging ADCs by removing the bottleneck and allowing both ADCs to run at full speed.