741 research outputs found
Design and Analysis of Low-power Millimeter-Wave SiGe BiCMOS Circuits with Application to Network Measurement Systems
Interest in millimeter (mm-) wave frequencies covering the spectrum of 30-300 GHz has been steadily increasing. Advantages such as larger absolute bandwidth and smaller form-factor have made this frequency region attractive for numerous applications, including high-speed wireless communication, sensing, material science, health, automotive radar, and space exploration. Continuous development of silicon-germanium heterojunction bipolar transistor (SiGe HBT) and associated BiCMOS technology has achieved transistors with fT/fmax of 505/720 GHz and integration with 55 nm CMOS. Such accomplishment and predictions of beyond THz performance have made SiGe BiCMOS technology the most competitive candidate for addressing the aforementioned applications.
Especially for mobile applications, a critical demand for future mm-wave applications will be low DC power consumption (Pdc), which requires a substantial reduction of supply voltage and current. Conventionally, reducing the supply voltage will lead to HBTs operating close to or in the saturation region, which is typically avoided in mm-wave circuits due to expectated performance degradation and often inaccurate models. However, due to only moderate speed reduction at the forward-biased base-collector voltage (VBC) up to 0.5 V and the accuracy of the compact model HICUM/L2 also in saturation, low-power mm-wave circuits with SiGe HBTs operating in saturation offer intriguing benefits, which have been explored in this thesis based on 130 nm SiGe BiCMOS technologies:
• Different low-power mm-wave circuit blocks are discussed in detail, including low-noise amplifiers (LNAs), down-conversion mixers, and various frequency multipliers covering a wide frequency range from V-band (50-75 GHz) to G-band (140-220 GHz).
• Aiming at realizing a better trade-off between Pdc and RF performance, a drastic decrease in supply voltage is realized with forward-biased VBC, forcing transistors of the circuits to operate in saturation.
• Discussions contain the theoretical analysis of the key figure of merits (FoMs), topology and bias selection, device sizing, and performance enhancement techniques.
• A 173-207 GHz low-power amplifier with 23 dB gain and 3.2 mW Pdc, and a 72-108 GHz low-power tunable amplifier with 10-23 dB gain and 4-21 mW Pdc were designed.
• A 97 GHz low-power down-conversion mixer was presented with 9.6 dB conversion gain (CG) and 12 mW Pdc.
• For multipliers, a 56-66 GHz low-power frequency quadrupler with -3.6 dB peak CG and 12 mW Pdc, and a 172-201 GHz low-power frequency tripler with -4 dB peak CG and 10.5 mW Pdc were realized. By cascading these two circuits, also a 176-193 GHz low-power ×12 multiplier was designed, achieving -11 dBm output power with only 26 mW Pdc.
• An integrated 190 GHz low-power receiver was designed as one receiving channel of a G-band frequency extender specifically for a VNA-based measurement system. Another goal of this receiver is to explore the lowest possible Pdc while keeping its highly competitive RF performance for general applications requiring a wide LO tuning range. Apart from the low-power design method of circuit blocks, the careful analysis and distribution of the receiver FoMs are also applied for further reduction of the overall Pdc. Along this line, this receiver achieved a peak CG of 49 dB with a 14 dB tunning range, consuming only 29 mW static Pdc for the core part and 171 mW overall Pdc, including the LO chain.
• All designs presented in this thesis were fabricated and characterized on-wafer. Thanks to the accurate compact model HICUM/L2, first-pass access was achieved for all circuits, and simulation results show excellent agreement with measurements.
• Compared with recently published work, most of the designs in this thesis show extremely low Pdc with highly competitive key FoMs regarding gain, bandwidth, and noise figure.
• The observed excellent measurement-simulation agreement enables the sensitivity analysis of each design for obtaining a deeper insight into the impact of transistor-related physical effects on critical circuit performance parameters. Such studies provide meaningful feedback for process improvement and modeling development.:Table of Contents
Kurzfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
1 Introduction 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
List of symbols and acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Technology 7
2.1 Fabrication Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1.1 SiGe HBT performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1.2 B11HFC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.3 SG13G2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.4 SG13D7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2 Commonly Used Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.2.1 Grounded-sidewall-shielded microstrip line . . . . . . . . . . . . . . . . . . 12
2.2.2 Zero-impedance Transmission Line . . . . . . . . . . . . . . . . . . . . . . 15
2.2.3 Balun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.3.1 Active Balun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.2.3.2 Passive Balun . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3 Low-power Low-noise Amplifiers 25
3.1 173-207 GHz Ultra-low-power Amplifier . . . . . . . . . . . . . . . . . . . . . . . 25
3.1.1 Topology Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.1.2 Bias Dependency of the Small-signal Performance . . . . . . . . . . . . . 27
3.1.2.1 Bias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.1.2.2 Bias vs Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.1.2.3 Bias vs Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.1.2.4 Bias vs Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.1.3 Bias selection and Device sizing . . . . . . . . . . . . . . . . . . . . . . . . 36
3.1.3.1 Bias Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.1.3.2 Device Sizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.1.4 Performance Enhancement Technologies . . . . . . . . . . . . . . . . . . . 41
3.1.4.1 Gm-boosting Inductors . . . . . . . . . . . . . . . . . . . . . . . 41
3.1.4.2 Stability Enhancement . . . . . . . . . . . . . . . . . . . . . . . 43
3.1.4.3 Noise Improvement . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.1.5 Circuit Realization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.1.5.1 Layout Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.1.5.2 Inductors Design . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
3.1.5.3 Dual-band Matching Network . . . . . . . . . . . . . . . . . . . 48
3.1.5.4 Circuit Implementation . . . . . . . . . . . . . . . . . . . . . . . 50
3.1.6 Results and Discussions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
3.1.6.1 Measurement Setup . . . . . . . . . . . . . . . . . . . . . . . . . 51
3.1.6.2 Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . 51
3.1.6.3 Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
3.2 72-108 GHz Low-Power Tunable Amplifier . . . . . . . . . . . . . . . . . . . . . . 55
3.2.1 Configuration, Sizing, and Bias Tuning Range . . . . . . . . . . . . . . . . 55
3.2.2 Regional Matching Network . . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.2.2.1 Impedance Variation . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.2.2.2 Regional Matching Network Design . . . . . . . . . . . . . . . . 60
3.2.3 Circuit Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
3.2.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
3.2.4.1 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
3.2.4.2 Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
3.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
4 Low-power Down-conversion Mixers 73
4.1 97 GHz Low-power Down-conversion Mixer . . . . . . . . . . . . . . . . . . . . . 74
4.1.1 Mixer Design and Implementation . . . . . . . . . . . . . . . . . . . . . . 74
4.1.1.1 Mixer Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.1.1.2 Bias Selection and Device Sizing . . . . . . . . . . . . . . . . . . 77
4.1.1.3 Mixer Implementation . . . . . . . . . . . . . . . . . . . . . . . . 79
4.1.2 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
4.1.2.1 Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . 80
4.1.2.2 Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
4.2 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
5 Low-power Multipliers 87
5.1 General Design Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
5.2 56-66 GHz Low-power Frequency Quadrupler . . . . . . . . . . . . . . . . . . . . 89
5.3 172-201 GHz Low-power Frequency Tripler . . . . . . . . . . . . . . . . . . . . . 93
5.4 176-193 GHz Low-power Ă—12 Frequency Multiplier . . . . . . . . . . . . . . . . . 96
5.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
6 Low-power Receivers 101
6.1 Receiver Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
6.2 LO Chain (Ă—12) Integrated 190 GHz Low-Power Receiver . . . . . . . . . . . . . 104
6.2.1 Receiver Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
6.2.2 Low-power Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
6.2.3 Building Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
6.2.3.1 LNA and LO DA . . . . . . . . . . . . . . . . . . . . . . . . . . 108
6.2.3.2 Tunable Mixer and IF BA . . . . . . . . . . . . . . . . . . . . . 111
6.2.3.3 65 GHz (V-band) Quadrupler . . . . . . . . . . . . . . . . . . . 116
6.2.3.4 G-band Tripler . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
6.2.4 Receiver Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . 123
6.2.5 Measurement Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
6.2.6 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
6.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
7 Conclusions 133
7.1 Summaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7.2 Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Bibliography 135
List of Figures 149
List of Tables 157
A Derivation of the Gm 159
A.1 Gm of standard cascode stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
A.2 Gm of cascode stage with Lcas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
A.3 Gm of cascode stage with Lb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
B Derivation of Yin in the stability analysis 163
C Derivation of Zin and Zout 165
C.1 Zin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
C.2 Zout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
D Derivation of the cascaded oP1dB 169
E Table of element values for the designed circuits 17
International Experience and Enlightenment of Microcredit Pattern
The success of microcredit within the international range depends on the use of the group credit, dynamic incentive, regular payment, Center meeting system, guarantee substitute and many other kinds of technologies to solve the problems effectively in the process of loan which are difficult to enforce, not easy to supervise. According to the different economic backgrounds, we should draw into and create new loan mechanisms and technologies.Key words: Microcredit; Pattern; International experienc
A Probe Into the Sustainable Development of Petty Loan Companies
The petty loan companies in China have been in good performance since taken the pilot demonstration, which effectively relieves the rural funds and financing difficulties of SMEs. However, the petty loan companies in the business development also face many problems, such as the unreasonable legal status, the limited sources of funding, the heavy tax burden, high cost, and operational risks, and so on. These issues will be restricted to the sustainable development of petty loan companies. This thesis is in-depth analysis of the problems of petty loan companies in terms of sustainable development, and puts forward suggestions to promote the sustainable development of petty loan companies
The Analysis of Government's Role in the Development of Scientific and Technological Finance: Illustrated by the Case of liaoning Province
The development of sci-tech finance is largely dependent on the participation and support of the government, for it effectively supplements the insufficient by the invisible hand which includes the externalities of science and technology innovation and financial market failure, etc. Thereby, the government plays a Leading role in the process of enterprise independent innovation. The government’s effects are composed of policies support, investment guide, market system construction and perfect the related law. At this stage, the government should play an important role in innovating the way of fiscal expenditure on science and technology and perfecting implementation of the preferential tax policy
A 185-215-GHz Subharmonic Resistive Graphene FET Integrated Mixer on Silicon
A 200-GHz integrated resistive subharmonic mixer based on a single chemical vapor deposition graphene field-effect transistor (G-FET) is demonstrated experimentally. This device has a gate length of 0.5 μm and a gate width of 2x40 μm. The G-FET channel is patterned into an array of bow-tie-shaped nanoconstrictions, resulting in the device impedance levels of ~50 Ω and the ON-OFF ratios of ≥4. The integrated mixer circuit is implemented in coplanar waveguide technology and realized on a 100-μm-thick highly resistive silicon substrate. The mixer conversion loss is measured to be 29 ± 2 dB across the 185-210-GHz band with 12.5-11.5 dBm of local oscillator (LO) pump power and >15-dB LO-RF isolation. The estimated 3-dB IF bandwidth is 15 GHz
Phosphorus Recovery by Struvite Crystallization from Livestock Wastewater and Reuse as Fertilizer: A Review
In China, the intensive livestock farming produces massive livestock wastewater with high concentration of phosphorus. Discharge of these compounds to surface water not only causes water eutrophication but also wastes phosphorus resources for plant growth. Therefore, it’s necessary combining the removal of phosphorus from livestock wastewater with its recovery and reuse as fertilizer. As a valuable slow-release mineral fertilizer, struvite crystallization has become a focus in phosphorus recovery. In this chapter, struvite crystallization mechanism, reaction factors, crystallizers, and the applications of struvite as fertilizer are discussed. Two steps of nucleation and crystal growth for struvite crystallization from generation to growth are introduced. The reaction factors, including molar ratio of magnesium and phosphate, solution pH, coexisting substances, and seeding assist, of struvite crystallization are summarized. Several innovate types of crystallizer, which relate to the shape and size of harvest struvite to realize the phosphorus recycling, are demonstrated. Due to the influence of toxic or harmful impurities in struvite on its reuse as fertilizer, the environmental risk evaluation of struvite application is introduced. In conclusion, struvite crystallization is a promising tool for recovering phosphorus from livestock wastewater
The Adversarial Attack and Detection under the Fisher Information Metric
Many deep learning models are vulnerable to the adversarial attack, i.e.,
imperceptible but intentionally-designed perturbations to the input can cause
incorrect output of the networks. In this paper, using information geometry, we
provide a reasonable explanation for the vulnerability of deep learning models.
By considering the data space as a non-linear space with the Fisher information
metric induced from a neural network, we first propose an adversarial attack
algorithm termed one-step spectral attack (OSSA). The method is described by a
constrained quadratic form of the Fisher information matrix, where the optimal
adversarial perturbation is given by the first eigenvector, and the model
vulnerability is reflected by the eigenvalues. The larger an eigenvalue is, the
more vulnerable the model is to be attacked by the corresponding eigenvector.
Taking advantage of the property, we also propose an adversarial detection
method with the eigenvalues serving as characteristics. Both our attack and
detection algorithms are numerically optimized to work efficiently on large
datasets. Our evaluations show superior performance compared with other
methods, implying that the Fisher information is a promising approach to
investigate the adversarial attacks and defenses.Comment: Accepted as an AAAI-2019 oral pape
Biochar Adsorption Treatment for Typical Pollutants Removal in Livestock Wastewater: A Review
Biochar, as an high efficiency, environmental friendly, and low-cost adsorbent, is usually used as soil conditioner, bio-fuel, and carbon sequestration regent. Recently, biochar has attracted much attention in wastewater treatment field. There are plenty of studies about application of biochar to adsorb pollutants in wastewater, because of its low-cost preparation, high surface area, large pore volume, plentiful functional groups, and environmental stability. Furthermore, it can be reused due to their high treatment efficiency and resource recovery potential. As biochar can be used for adsorption of typical pollutants in livestock wastewater, it becomes a promising method to treat livestock wastewater. The preparation methods, including pyrolysis, hydrothermal carbonization, and gasification, were introduced. The applications of biochar to adsorb typical pollutants, such as organic pollutants, heavy metals, and nutrients, in livestock wastewater were present. The organic structures, surface functional groups, surface electricity, and mineral component of biochar were investigated to explain the adsorption mechanism of organic pollutants, heavy metals, and nutrients in wastewater. Finally, outlooks were made for the better use of biochar in future. The relationship of preparation parameters, structures, and adsorption performance of biochar should be discussed. The quantitative analysis for the adsorption of organic structures, surface functional groups, surface electricity, and mineral component should be performed. The disposal of post-sorption biochar should be investigated
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