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Article
Publication date: 29 May 2020

Anton V. Ubaychin, Tilekbek Abdirasul Uulu and Grigory Zhuk

This paper aims to describe a new microwave radiometer designed for sensing natural mediums to solve various applied scientific problems. The research findings enable to…

Abstract

Purpose

This paper aims to describe a new microwave radiometer designed for sensing natural mediums to solve various applied scientific problems. The research findings enable to make assertions about high efficiency of the described microwave radiometer being a part of mobile sensor systems with self-contained power supplies.

Design/methodology/approach

A new microwave radiometer is based on the modification of the null method. Modification of the null method has been implemented by using two reference noise generators. The first reference noise generator is passive and its implementation is based on the matched load. A low-noise amplifier is used as the second reference noise generator. The use of the low-noise amplifier as the reference noise generator is based on the noise wave generation effect at its input whereby the waves form low-temperature noise.

Findings

The use of the low-noise amplifier as the reference noise generator in the modified microwave radiometer has made it possible to simplify the device design at the system level while reducing the weight and power consumption and increasing sensitivity.

Originality/value

The novelty of the modified radiometer lies in the modification of the null method and the removal of high-temperature reference noise generators based on avalanche transit-time diodes. Further, the novelty lies in the invariance of measurement results toward changes in the receiver’s own noise and transmission factor while the design of the device has been simplified.

Details

Sensor Review, vol. 40 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 5 December 2019

Deepak Balodi, Arunima Verma and Ananta Govindacharyulu Paravastu

The paper aims to present the novel design approach for a low power LC-voltage-controlled oscillators (VCO) design with low phase noise that too targeted at the most…

Abstract

Purpose

The paper aims to present the novel design approach for a low power LC-voltage-controlled oscillators (VCO) design with low phase noise that too targeted at the most sought band of Bluetooth applications. Owing to their crucial role in a wide variety of modern applications, VCO and phase-locked loop (PLL) frequency synthesizers have been the subject of extensive research in recent years. In fact, VCO is one of the key components being used in a modern PLL to provide local frequency signal since a few decades. The complicated synthesizer requirements imposed by cellular phone applications have been a key driver for PLL research.

Design/methodology/approach

This paper first opted to present the recent developments on implemented techniques of LC-VCO designs in popular RF bands. An LC-VCO with a differential (cross-coupled) MOS structure is then presented which has aimed to compensate the losses of an on-chip inductor implemented in UMC’s 130 nm RF-CMOS process. The LC-VCO is finally targeted to embed onto the synthesizer chip, to address the narrowband (S-Band) applications where Bluetooth has been the most sought one. The stacked inductor topology has been adopted to get the benefit of its on-chip compatibility and low noise. The active differential architecture, which basically is a cross-coupled NMOS structure, has been then envisaged for the gain which counters the losses completely. Three major areas of LC-VCO design are considered and worked upon for the optimum design parameters, which includes Bluetooth coverage range of 2.410 GHz to 2.490 GHz, better linearity and high sensitivity and finally the most sought phase noise performance for an LC-VCO.

Findings

The work provides the complete design aspect of a novel LC-VCO design for low phase noise narrowband applications such as Bluetooth. Using tuned MOS varactor, in 130 nm-RF CMOS process, a high gain sensitivity of 194 MHz/Volt was obtained. Thus, the entire frequency range of 2415-2500 MHz for Bluetooth applications, supporting multiple standards from 3G to 5G, was covered by voltage tuning of 0.7-1.0 V. To achieve the low power dissipation, low bias (1.2 V) cross-coupled differential structure was adopted, which completely paid for the losses occurred in the LC resonator. The power dissipation comes out to be 8.56 mW which is a remarkably small value for such a high gain and low noise VCO. For the VCO frequencies in the presented LO-plan, the tank inductor was allowed to have a moderate value of inductance (8 nH), while maintaining a very high Q factor. The LC-VCO of the proposed LO-generator achieved extremely low phase noise of −140 dBc/Hz @ 1 MHz, as compared to the contemporary designs.

Research limitations/implications

Though a professional tool for inductor and circuit design (ADS-by Keysight Technologies) has been chosen, actual inductor and circuit implementation on silicon may still lead to various parasitic evolutions; therefore, one must have that margin pre-considered while finalizing the design and testing it.

Practical implications

The proposed LC-VCO architecture presented in this work shows low phase noise and wide tuning range with high gain sensitivity in S-Band, low power dissipation and narrowband nature of wireless applications.

Originality/value

The on-chip stacked inductor has uniquely been designed with the provided dimensions and other parameters. Though active design is in a conventional manner, its sizing and bias current selection are unique. The pool of results obtained completely preserves the originally to the full extent.

Details

Circuit World, vol. 46 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 January 1972

JOHN W. LEVERTON, MScEng and BTech

SINCE in the context of this article it is the civil air transport application of rotorcraft which is of interest, only large passenger carrying rotorcraft are considered.

Abstract

SINCE in the context of this article it is the civil air transport application of rotorcraft which is of interest, only large passenger carrying rotorcraft are considered.

Details

Aircraft Engineering and Aerospace Technology, vol. 44 no. 1
Type: Research Article
ISSN: 0002-2667

Abstract

Details

Urban Transport and the Environment
Type: Book
ISBN: 978-0-08-047029-0

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Article
Publication date: 9 March 2015

Nikki Bell, Jennifer Lunt, Jennifer Webster and Tim Ward

The purpose of this paper is to investigate the dimensions that distinguish high from low performing manufacturing companies in Great Britain with respect to controlling…

Abstract

Purpose

The purpose of this paper is to investigate the dimensions that distinguish high from low performing manufacturing companies in Great Britain with respect to controlling noise. The findings should assist regulators and industry to develop interventions that help organisations to effectively manage noise, particularly amongst the low performers.

Design/methodology/approach

The research uses quantitative and qualitative methods. Survey data was obtained from 215 manufacturers and supplemented with 15 qualitative interviews to assess performance and individual, social, environmental and organisational influences on duty holders' decision making for controlling noise.

Findings

Relative to low performers, decision makers from high performing companies had: greater in-depth knowledge of noise risks and controls; taken steps to promote positive health and safety attitudes and values; were large companies; and faced fewer resource barriers (time, costs, staffing). Managers in small, low performing companies sought simple interventions with a practical focus.

Research limitations/implications

The differences reported between high and low performing companies showed a small magnitude of effect but these are considered significant in a health and safety context.

Practical implications

Improvements in training and education, and addressing workplace health and safety culture, are recommended as offering most potential to raise the standard of noise control.

Originality/value

To the authors’ knowledge, this is the first study to systematically assess the specific knowledge, attitudes, values and beliefs that employers hold about noise and the influence of social, environmental and organisational factors on manager’s decisions about noise controls.

Details

International Journal of Workplace Health Management, vol. 8 no. 1
Type: Research Article
ISSN: 1753-8351

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Article
Publication date: 1 June 2015

Adam Witold Stadler, Andrzej Kolek, Krzysztof Mleczko, Zbigniew Zawiślak, Andrzej Dziedzic and Wojciech Stęplewski

The paper aims to get the knowledge about electrical properties, including noise, of modern polymer thick-film resistors (TFRs) in a wide range of temperature values, i.e…

Abstract

Purpose

The paper aims to get the knowledge about electrical properties, including noise, of modern polymer thick-film resistors (TFRs) in a wide range of temperature values, i.e. from 77 K up to room temperature. The sample resistors have been made of different combinations of resistive compositions, either ED7100 or MINICO (M2013, M2010), and conducting pastes (for contacts) Cu- or Au-based, deposited on FR-4 laminate.

Design/methodology/approach

The paper opted for an experimental study using either current noise index measurement in room temperature for large batch of samples or noise spectra measurement in temperature range 77-300 K for selected samples. Obtained noise maps, i.e. plots of power spectral density of voltage fluctuations vs frequency and temperature, have been used for evaluation of noise describing parameters like material noise intensity C and figure of merit K, for TFRs made of different combinations of resistive/conductive materials. Comparison of the parameters gives the information about the quality of the technology and matching the conductive/resistive materials.

Findings

Experiments confirmed that the main noise component is 1/f resistance noise. However, low-frequency noise spectroscopy revealed that also noise components of Lorentzian shape, associated with thermally activated noise sources exist. Their activation energies have been found to be of a few tenths of eV.

Research limitations/implications

The noise intensity of polymer TFRs depends on technology process and/or contacts materials. The use of Au contacts leads to better noise properties of the resistors. The results of the studies might be helpful for further improvement of thick-film technology, especially for manufacturing low-noise, stable and reliable TFRs.

Practical implications

The paper includes indications for the materials selection for thick-film technology to manufacture low-noise, reliable and stable TFRs.

Originality/value

Experimental studies of electrical properties of polymer TFRs by means of noise spectra measurements in wide range of temperature is rare. They give fundamental knowledge about noise sources in the modern passive electronic components as well as practical indications of selection material for thick-film technology, to obtain high performance components and get technological advantage.

Details

Soldering & Surface Mount Technology, vol. 27 no. 3
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 4 May 2012

Mei‐Ling Yeh, Yao‐Chian Lin and Wei‐Chieh Chang

The purpose of this paper is to design a low phase noise and high figure of merit, fully integrated, voltage‐controlled oscillator (VCO) which was fabricated in TSMC CMOS…

Abstract

Purpose

The purpose of this paper is to design a low phase noise and high figure of merit, fully integrated, voltage‐controlled oscillator (VCO) which was fabricated in TSMC CMOS 0.18‐μm 1P6M process.

Design/methodology/approach

A differential PMOS cross‐coupled architecture VCO with the capacitive feedback technology was designed to increase the linearity of frequency tuning range and decrease the phase noise. Varactor determining the performance of tuning range is also a key component in the design of VCO. The authors adopt the accumulation‐mode MOS varactor. The output spectrum and the phase noise are measured by E5052A spectrum analyzer.

Findings

The VCO is successfully fabricated in TSMC RF CMOS 0.18um 1P6M process. The measured tuning range is from 10.875 GHz ∼ 11.1 GHz with control voltage from 0 to 1.5 V. The measured phase noise is as low as −120.42 dBc/Hz at 1 MHz offset and the high FOM is −189.5 dBc/Hz. The output spectrum is −10.51dBm with center oscillator frequency of 10.942 GHz. The core circuit without buffer consumes power of 15 mW from a 1.8 V supply voltage.

Originality/value

This paper shows a fully integrated CMOS LCVCO architecture using capacitive feedback technology with low phase noise and high figure of merit for OC‐192 SONET applications.

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Article
Publication date: 16 November 2018

Michael J. McCord, Sean MacIntyre, Paul Bidanset, Daniel Lo and Peadar Davis

Air quality, noise and proximity to urban infrastructure can arguably have an important impact on the quality of life. Environmental quality (the price of good health) has…

Abstract

Purpose

Air quality, noise and proximity to urban infrastructure can arguably have an important impact on the quality of life. Environmental quality (the price of good health) has become a central tenet for consumer choice in urban locales when deciding on a residential neighbourhood. Unlike the market for most tangible goods, the market for environmental quality does not yield an observable per unit price effect. As no explicit price exists for a unit of environmental quality, this paper aims to use the housing market to derive its implicit price and test whether these constituent elements of health and well-being are indeed capitalised into property prices and thus implicitly priced in the market place.

Design/methodology/approach

A considerable number of studies have used hedonic pricing models by incorporating spatial effects to assess the impact of air quality, noise and proximity to noise pollutants on property market pricing. This study presents a spatial analysis of air quality and noise pollution and their association with house prices, using 2,501 sale transactions for the period 2013. To assess the impact of the pollutants, three different spatial modelling approaches are used, namely, ordinary least squares using spatial dummies, a geographically weighted regression (GWR) and a spatial lag model (SLM).

Findings

The findings suggest that air quality pollutants have an adverse impact on house prices, which fluctuate across the urban area. The analysis suggests that the noise level does matter, although this varies significantly over the urban setting and varies by source.

Originality/value

Air quality and environmental noise pollution are important concerns for health and well-being. Noise impact seems to depend not only on the noise intensity to which dwellings are exposed but also on the nature of the noise source. This may suggest the presence of other externalities that arouse social aversion. This research presents an original study utilising advanced spatial modelling approaches. The research has value in further understanding the market impact of environmental factors and in providing findings to support local air zone management strategies, noise abatement and management strategies and is of value to the wider urban planning and public health disciplines.

Details

Journal of European Real Estate Research, vol. 11 no. 3
Type: Research Article
ISSN: 1753-9269

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Article
Publication date: 26 July 2013

Joon Huang Chuah and David Holburn

The purpose of this paper is to design a very lownoise transimpedance amplifier (TIA) for a novel multi‐pixel CMOS photon detector which performs secondary electron (SE…

Abstract

Purpose

The purpose of this paper is to design a very lownoise transimpedance amplifier (TIA) for a novel multi‐pixel CMOS photon detector which performs secondary electron (SE) detection in the scanning electron microscope (SEM).

Design/methodology/approach

The TIA, which is implemented with three‐stage push‐pull inverters, is optimised using a nomograph technique developed in MATLAB. SPICE simulations are conducted to verify the results generated from MATLAB. Important performance figures are obtained experimentally and these measurements are compared with simulation results.

Findings

A lownoise TIA fabricated in a standard 0.35 μm CMOS technology was tested. Experimental results obtained show that the TIA connected to a photodiode with a junction capacitance of 0.8 pF can carry out its task effectively with a transimpedance gain of 126.9 dBΩ, a bandwidth of 9.8 MHz, an input‐referred noise of 2.50×10−13 A/√Hz and an SNR of 12.8. The power consumption of the TIA was 49.3 mW. These encouraging results have exhibited the potential of the circuit for use in the CMOS photon detector.

Originality/value

This paper presents a lownoise transimpedance amplifier that is highly suitable to be used as a critical constituent block for the CMOS photon detector which aims to take over the role of photomultiplier tube in SE detection in the SEM. Solid‐state approaches have recently been reinvigorated for improving certain aspects of SE detection in scanning electron microscopy and this work has supported and contributed to the trend.

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Article
Publication date: 1 February 1967

F.B. Greatrex and R. Bridge

DURING the 1950s noise around airports increased steadily with increasing traffic and size of aircraft. With the introduction of heavy jet transports the very different…

Abstract

DURING the 1950s noise around airports increased steadily with increasing traffic and size of aircraft. With the introduction of heavy jet transports the very different quality of noise (compared to piston engines) highlighted the problem and the upward trend had to be halted. This led to a considerable increase in effort to investigate the noise of turbojet engines.

Details

Aircraft Engineering and Aerospace Technology, vol. 39 no. 2
Type: Research Article
ISSN: 0002-2667

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