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A 1-V 2.4 GHz low-spur phase-locked loop (PLL) fractional-N frequency synthesizer with a subsampling charge pump and a randomly selected phase frequency detector is implemented by TSMC 0.18-μm CMOS process. The proposed frequency synthesizer randomizes the periodic ripples on the controlled voltage from the voltage-controlled oscillator to reduce the reference spur at the output of the PLL. A random clock generator is used to perform this random selection control. At 1-V supply voltage, measured results of the proposed prototype achieve the tuning range of 2.235–2.579 GHz, corresponding to 14.3%, a phase noise of −113.17 dBc/Hz at 1 MHz offset frequency from 2.41 GHz, an output power of −4.534 dBm with a reference spur of −70.4 dBc and a power consumption of 9 mW. Including pads, the chip area only occupies 0.695 (0.819 × 0.849) mm2. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:61–66, 2015

A 2.4-GHz integer-N frequency synthesizer is implemented in TSMC 0.18-μm CMOS process. This article proposes a charge pump (CP) linearization technique and uses a current-switching differential Colpitts VCO to lower the phase noise and an averaged varactor circuit to increase the linearity of the VCO tuning range. A three phase sample-hold-reset loop filter that isolates the CP output node from the VCO tuning node, which improves synthesizer spur performance, minimizes phase noise and reduces on-chip capacitors area. At 1.8 V supply voltage, measured results of the proposed prototype achieves a wide tuning range from 2.24 to 2.42 GHz, corresponding to 7.7%, a phase noise of −114.76 dBc/Hz at 1 MHz offset frequency from 2.4 GHz, a power consumption of 13.6 mW and an output power of −8.43 dBm. Including pads, the chip area only occupies 0.849 (0.899 × 0.944) mm2. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2591–2598, 2014

Transmission line gallopingis self-excited vibration of iced conductor with low frequency and largeamplitude, the countries almost all over the world have occurred transmissionline galloping, which caused a great economic loss. Drawing the effectivedistribution map for galloping plays an important role in guiding theanti-galloping design, the key of this work is to establish a scientific methodfor galloping region division. In this paper, several methods for gallopingregion division were introduced: frequency method, coefficient method andmeteorological-geographical method. This paper also compared the applicabilityof various methods and their advantages and disadvantages. It shows that themeteorological-geographical method is the best choice for us to dividegalloping region at the present time. However, in the practical application, weshould take all the applicability of the three methods into consideration toget a reasonable division for galloping region.

So as to decrease the cost and time of the development, it is significance to solve the section instability problem of diameter-expanded conductor during the design stage. The solution is developing a finite-element simulation program for the study of section stability; however, a proper modeling method is not necessary. In this paper, the parametric study on simulation modeling of diameter-expanded conductor is carried out and through the investigation, analysis and verification; a kind of test method has been designed for the study. After a series of test under different tensions, the numbers of sheave, the position of strand jumping, the section states and the indentation states have been gotten. At last, a parametric finite-element program for strand jumping prediction has been simulated and the result shows that the code developed is reliable based on the comparison of the calculated results and the measured ones.

this paper presents the rendering method of galloping distribution plan for power transmission line based on the meteorological geographical model by summarizing theory on division of galloping region, e.g. frequency method and galloping coefficient method. Meteorological geographical method is to account and analyze icing galloping conditions of power transmission line over the years and sum up meteorological and topographic features and laws to create meteorological and topographic model for icing galloping and work out division and classification if galloping region based on running experience so as to establish standard technical system for rendering galloping distribution plan and complete the galloping distribution plan.

Sufficient icing data are very important for the design and operation of power grid in the places with potential accreted ice, meaning that it is necessary to pay due attention to the ice measurement devices. In this paper, the current ice measurement devices are classified into different types according to corresponding classification criteria with the aim of understanding the characteristics of each type of devices. Moreover, the research progress of the manual ice measurement devices are introduced in detail, including the diameter of conductors, the angle between conductor and wind direction. Finally, the existing problems are proposed for the further development of manual ice measurement devices for overhead transmission lines.

Standing up from a supine position or sitting down from standing is an important and simple human activity of day life. It is of equal importance for a humanoid robot, but it is not simple work to be completed for the robot. This paper presents the concept of generalized function set, and researches on the characteristics of lying state using the generalize function (GF) set, and gets the interested end effectors (EEs), which is instructional in the next detailed motion planning. Then the work presents the lying state classification of the humanoid robot SJTU-HR1.

The type synthesis of torsional mass dampers (TMDs for short) as anti-galloping devices is very import for the safe operation of power grid. In this paper, the TMDs are considered as passive robotic manipulators, with the aim of introducing planar four-bar mechanisms into the synthesis of TMDs. By utilizing one planar four-bar mechanism or two planar four-bar mechanisms in a single TMDs, 6 TMDs with symmetrical structures and 18 TMDs with non-symmetrical structures are synthesized, which may improve the reasonable applications of the TMDs for the solving the anti-galloping issue of power grid.

A 2.4 GHz integer-N frequency synthesizer is implemented in tsmc 0.18-μm CMOS process. This paper proposes a new supply regulated LC-VCO that reduces the impact of process variations and temperature on current consumption and phase noise is proposed, as well as a new single-ended charge pump architecture that offers very high output impedance over a wide output voltage range. This frequency synthesizer dedicated to implantable smart medical devices, optimized for ultra-low power operation, is being integrated in the transceiver of an implantable wireless sensing microsystem (IWSM), which is dedicated to in vivo monitoring of biological parameters such as PPG, ECG (Electrocardiography) and EMG. At 1.8 V supply voltage, measured results of the proposed prototype achieves a wide tuning range from 2.24 to 2.42 GHz, corresponding to 7.7%, a phase noise of-114.76 dBc/Hz at 1 MHz offset frequency from 2.4 GHz, a power consumption of 13.6 mW and an output power of-8.43 dBm for microsystem application.

A 5.6-GHz 1-V wide tuning range frequency synthesizer with a gain-boosting Colpitts voltage-controlled oscillator (VCO) is fabricated in TSMC 0.18 um CMOS process. In this prototype, there are two important features. First, a 1-V gain-boosting Colpitts LC VCO circuit is adopted to reduce phase noise and power consumption. Second, a class-AB current mode logic (CML) circuit is utilized in first divider stage to deal with the high frequency signal. At the supply voltages of 1-V for VCO and 1.8-V for digital circuits, measured results achieve that the VCO output frequency is tunable from 5.13∼5.98 GHz corresponding to 15.4% and the locked phase noise is −105.83 dBc/Hz at 1MHz from 5.15 GHz. The power consumption is 5.6 mW and including pads, the chip area is 0.632 (0.89 × 0.71) mm2. This chip design low power consumption for biomedical application.

A 5.8-GHz frequency synthesizer is implemented in TSMC 0.18-μm CMOS process. This paper proposes a dynamic current-matching charge pump linearization technique and uses a current-switching differential Colpitts VCO to lower the phase noise and an averaged varactor circuit to increase the linearity of the VCO tuning range. At the supply voltage of 1.8 V, measured results achieve the locked tuning frequency from 5.55 to 5.94 GHz, corresponding to 6.8 % and the phase noise of −105.83 dBc/Hz at 1 MHz offset frequency from 5.8 GHz. The overall power consumption is 21.6 mW. Including pads, the chip area is 0.729 (0.961 × 0.761) mm2.

The making of regional ice-load maps is crucial to the effective anti-icing design for overhead transmission lines. And it is a complex work and has different properties in different countries. A systematic method to create regional ice-load maps for transmission lines is proposed based on the actual conditions in China. The process includes the collection of meteorological observation data and icing accident data, calculation of the equivalent radial ice thickness, numerical simulation of ice accretion, spatial interpolation for ice data, correction on altitude, map drawing and development of visualization software system. The maps obtained by this method are more effective and accurate, especially for the region where the historical observation data are shortage. And finally, a visualization software system is obtained, which is easily accessed for ice data and conveniently implemented for realtime update of ice maps with the increase of observed data.