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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 sought band…

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

Keywords

Article
Publication date: 1 April 2003

Patrick Bell, Nils Hoivik, Victor Bright and Zoya Popovic

A frequency tunable half‐wave resonator at 3 GHz is presented with a microelectromechanical systems (MEMS) variable capacitor as the tuning element. The capacitor is fabricated…

Abstract

A frequency tunable half‐wave resonator at 3 GHz is presented with a microelectromechanical systems (MEMS) variable capacitor as the tuning element. The capacitor is fabricated using the multi‐user MEMS process (MUMPs) technology provided by JDS/Cronos, and transferred to an alumina substrate by an in‐house developed flip‐chip process. This capacitor is electrostatically actuated. The resulting CV response is linear with a slope of 0.05 pF/V for a wide range of actuation voltages. The MEMS device has a capacitance ratio of 3:1 for 0‐70 V bias, with a Q‐factor of 140 measured at 1 GHz. A half‐wave tunable microstrip resonator with bias lines is designed to include this MEMS device, which exhibits linear tuning over 180 MHz (6 percent) centered around 3 GHz with a constant 3 dB bandwidth of 160 MHz over the entire tuning range. The power consumption of the MEMS device was measured to be negligible.

Details

Microelectronics International, vol. 20 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 27 July 2012

Siti Maisurah Mohd Hassan, Mohd Azmi Ismail, Nazif Emran Farid, Norman Fadhil Idham Muhammad and Ahmad Ismat Abdul Rahim

The purpose of this paper is to design and implement a fully integrated low‐phase noise and large tuning range dual‐band LC voltage‐controlled oscillator (VCO) in 0.13 μm…

Abstract

Purpose

The purpose of this paper is to design and implement a fully integrated low‐phase noise and large tuning range dual‐band LC voltage‐controlled oscillator (VCO) in 0.13 μm complementary metal oxide semiconductor (CMOS) technology.

Design/methodology/approach

Two parallel‐connected single‐band VCOs are designed to implement the proposed VCO. Adopting a simple and straight‐forward architecture, the dual‐band VCO is configured to operate at two frequency bands, which are from 1.48 GHz to 1.78 GHz and from 2.08 GHz to 2.45 GHz. A band selection circuit is designed to perform band selection process based on the controlling input signal.

Findings

The proposed VCO features phase noise of −104.7 dBc/Hz and −108.8 dBc/Hz at 1 MHz offset frequency for both low corner and high corner end of the low‐band operation. For high‐band operation, phase‐noise performance of −101.1 dBc/Hz and −110.4 dBc/Hz at 1 MHz offset frequency are achieved. The measured output power of the dual‐band VCO ranges from −8.4 dBm to −5.8 dBm and from −9.6 dBm to −8.0 dBm for low‐band and high‐band operation, respectively. It was also observed that the power differences between the fundamental spectrum and the nearby spurious tone range from −67.5 dBc to −47.7 dBc.

Originality/value

The paper is useful to both the academic and industrial fields since it promotes the concept of multi‐band or multi‐standard system which is currently in demand in the telecommunication industry.

Article
Publication date: 7 July 2023

Vinayambika S. Bhat, Thirunavukkarasu Indiran, Shanmuga Priya Selvanathan and Shreeranga Bhat

The purpose of this paper is to propose and validate a robust industrial control system. The aim is to design a Multivariable Proportional Integral controller that accommodates…

92

Abstract

Purpose

The purpose of this paper is to propose and validate a robust industrial control system. The aim is to design a Multivariable Proportional Integral controller that accommodates multiple responses while considering the process's control and noise parameters. In addition, this paper intended to develop a multidisciplinary approach by combining computational science, control engineering and statistical methodologies to ensure a resilient process with the best use of available resources.

Design/methodology/approach

Taguchi's robust design methodology and multi-response optimisation approaches are adopted to meet the research aims. Two-Input-Two-Output transfer function model of the distillation column system is investigated. In designing the control system, the Steady State Gain Matrix and process factors such as time constant (t) and time delay (?) are also used. The unique methodology is implemented and validated using the pilot plant's distillation column. To determine the robustness of the proposed control system, a simulation study, statistical analysis and real-time experimentation are conducted. In addition, the outcomes are compared to different control algorithms.

Findings

Research indicates that integral control parameters (Ki) affect outputs substantially more than proportional control parameters (Kp). The results of this paper show that control and noise parameters must be considered to make the control system robust. In addition, Taguchi's approach, in conjunction with multi-response optimisation, ensures robust controller design with optimal use of resources. Eventually, this research shows that the best outcomes for all the performance indices are achieved when Kp11 = 1.6859, Kp12 = −2.061, Kp21 = 3.1846, Kp22 = −1.2176, Ki11 = 1.0628, Ki12 = −1.2989, Ki21 = 2.454 and Ki22 = −0.7676.

Originality/value

This paper provides a step-by-step strategy for designing and validating a multi-response control system that accommodates controllable and uncontrollable parameters (noise parameters). The methodology can be used in any industrial Multi-Input-Multi-Output system to ensure process robustness. In addition, this paper proposes a multidisciplinary approach to industrial controller design that academics and industry can refine and improve.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 September 1965

Details of Electrical and Electronic Apparatus with Applications in the Maintenance and Operation of Aircraft, Missiles and Space Vehicles. A new type of tuneable magnetron, by…

Abstract

Details of Electrical and Electronic Apparatus with Applications in the Maintenance and Operation of Aircraft, Missiles and Space Vehicles. A new type of tuneable magnetron, by Milliard Ltd., is designed to provide the rapid and yet simple controlled frequency jumping required by diversity radar systems. Two versions are being marketed initially, the 80kW JPS9‐80, which is now in production, and the 200kW JPS9‐200, which is available as development samples. Both are in the X‐band frequency range.

Details

Aircraft Engineering and Aerospace Technology, vol. 37 no. 9
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 25 September 2020

Christof Naumzik and Stefan Feuerriegel

Trading on electricity markets occurs such that the price settlement takes place before delivery, often day-ahead. In practice, these prices are highly volatile as they largely…

Abstract

Purpose

Trading on electricity markets occurs such that the price settlement takes place before delivery, often day-ahead. In practice, these prices are highly volatile as they largely depend upon a range of variables such as electricity demand and the feed-in from renewable energy sources. Hence, the purpose of this paper is to provide accurate forecasts..

Design/methodology/approach

This paper aims at comparing different predictors stemming from supply-side (solar and wind power generation), demand-side, fuel-related and economic influences. For this reason, this paper implements a broad range of non-linear models from machine learning and draw upon the information-fusion-based sensitivity analysis.

Findings

This study disentangles the respective relevance of each predictor. This study shows that external predictors altogether decrease root mean squared errors by up to 21.96%. A Diebold-Mariano test statistically proves that the forecasting accuracy of the proposed machine learning models is superior.

Research limitations/implications

The performance gain from including more predictors might be larger than from a better model. Future research should place attention on expanding the data basis in electricity price forecasting.

Practical implications

When developing pricing models, practitioners can achieve reasonable performance with a simple model (e.g. seasonal-autoregressive moving-average) that is built upon a wide range of predictors.

Originality/value

The benefit of adding further predictors has only recently received traction; however, little is known about how the individual variables contribute to improving forecasts in machine learning.

Details

International Journal of Energy Sector Management, vol. 15 no. 1
Type: Research Article
ISSN: 1750-6220

Keywords

Article
Publication date: 26 January 2010

Harikrishnan Ramiah, Tun Zainal Azni Zulkifli and Noramalia Sapiee

The purpose of this paper is to design and realize a low‐phase noise, high‐output power, and high‐tuning range, fully integrated source injection parallel coupled (SIPC)‐based…

Abstract

Purpose

The purpose of this paper is to design and realize a low‐phase noise, high‐output power, and high‐tuning range, fully integrated source injection parallel coupled (SIPC)‐based inductor‐capacitor (LC)‐quadrature voltage controlled oscillator (QVCO) covering WiMAX frequency range in 0.18‐μm deep submicron CMOS technology.

Design/methodology/approach

A pMOS based‐SIPC LC‐QVCO topology is realized with the center frequency of 2.58 GHz. On chip spiral inductor is integrated with substantial quality factor, Q coupled with underlying pattern ground shield (PGS) shielding. An enhanced tuning range is achieved by integrating the diode connected MOS‐based varactors. The CMOS‐based autonomous SIPC LC‐QVCO circuit was characterized for its output phase noise, tuning range and power spectrum response via wafer probing, utilizing a signal source analyzer (Agilent E5052 A).

Findings

A quadrature oscillator catering to the needs of local oscillator (LO) generation covering the frequency range of WiMAX is realized. The parallel coupled architecture adapts direct source coupling, bypassing the LC resonator tank and relaxes the close in phase noise up‐conversion. The design consumes 2.19 mm2 of active chip area and measures a phase noise of −114.34 dBc/Hz at 1 MHz of offset frequency with 2.67 GHz of output frequency at 0.9 V of input tuning voltage. The corresponding output power measures to be −10.1 dBm, well suited for mixer hard switching. The design is realized in one poly, six metal 0.18‐μm standard CMOS technology.

Research limitations/implications

Owing to convergence discrepancy in the analysis, a diode‐connected MOS varactor is adapted in contrary to the accumulation mode MOS varactors with superior tuning range.

Practical implications

The designed SIPC LC‐QVCO is of need in the generation of low‐phase noise, highly matched quadrature LO generation covering the WiMAX frequency range. The adapted parallel coupling also relaxes the voltage headroom limitation.

Originality/value

This paper shows how a fully integrated CMOS‐based SIPC LC‐QVCO architecture is adapted with low‐output phase noise and low voltage headroom consumption covering the WiMAX frequency range.

Details

Microelectronics International, vol. 27 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 3 April 2018

Muhammad Awais, Harikrishnan Ramiah, Chee-Cheow Lim and Joon Huang Chuah

The purpose of this work in designing a wideband ring voltage-controlled oscillator (VCO) based on programmable current topology. It occupies a very tiny area yet achieving a good…

Abstract

Purpose

The purpose of this work in designing a wideband ring voltage-controlled oscillator (VCO) based on programmable current topology. It occupies a very tiny area yet achieving a good phase noise performance, which is suitable to be implemented in cost-effective and wideband frequency synthesizers.

Design/methodology/approach

The tuning range and gain are improved by dividing the VCO tuning curve into multiple curves controlled by programmable current sources without introducing additional parasitic capacitance.

Findings

Fabricated in 130-nm standard complementary metal oxide semiconductor technology and occupying an area of 0.079 mm2, the VCO is tunable from 2.05 to 4.19 GHz, with a tuning percentage of 68.5 per cent. The VCO measures a phase noise performance of −96.7 dBc/Hz at an offset of 1 MHz from a 4.19 GHz carrier while consuming an average current of 6.5 mA, achieving figure of merit (FoM) and FoMT of −158.9 and −175.6 dBc/Hz, respectively.

Originality/value

The proposed design uses programmable current topology without introducing parasitic capacitance, hence achieving wideband operation. It also occupies a tiny area and achieves a good phase noise performance.

Details

Microelectronics International, vol. 35 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 6 May 2020

Vikas Balikai and Harish Kittur

Biomedical radio frequency (RF) transceivers require miniaturized forms with long battery life and low power consumption. The medical implant communication service (MICS) band in…

Abstract

Purpose

Biomedical radio frequency (RF) transceivers require miniaturized forms with long battery life and low power consumption. The medical implant communication service (MICS) band in the frequency range of 402–405 MHz is widely used for medical RF transceivers because the MICS band signals have reasonable propagation characteristics and are suited to achieve good results. The implementation of the RF front-end for medical devices has many challenges as these dictate low power consumption. In particular, phase-locked loop is one of the most critical blocks of the RF front-end. The purpose of this paper is to the design of controller-based all-digital phase-locked loop (ADPLL) in a 45 nm CMOS process.

Design/methodology/approach

Initially, an open-loop architecture phase frequency detector (PFD) is designed. Then based on the concept of differential buffer, a differential ring oscillator (RO) is built using capacitive boosting technique. After that, the frequency controller block is built by proper mathematical modeling that does the job of loop filter, which behaves like a phase interpolator. Frequency controller block has tuning register block, tuning word register. The tuning block is built using the Metal Oxide Semiconductor (MOS) caps. Finally, the integration of all the blocks is done and the ADPLL architecture that locks at 402 MHz is achieved.

Findings

The designed PFD is dead zone free that operates at 1 GHz. The differential RO oscillates at 495 MHz. The proposed ADPLL operates at 402 MHz with measured phase noise of −98.36 at 1-MHz offset. This ADPLL exhibits rms jitter of 4.626 ps with a total power consumption of 216.5 µW.

Research limitations/implications

A time to digital converter (TDC)-less controller-based low power ADPLL covering the MICS frequency band for biomedical applications has been designed in 45 nm/0.68 V CMOS technology. The ADPLL proposed in this draft uses differential oscillator with capacitively boosted technique which reduced the operating voltage to as low as 0.68 V. This ADPLL has a bandwidth of 20 kHz and works at reference frequency of 20 MHz consumed power of 216.5 µW, while generating an output frequency of 402 MHz. The tuning range is from 375 to 428 MHz. With the phase noise of −98.36 dbc/Hz at 1 MHz, a frequency controller block replaces the usage of TDC.

Social implications

The designed ADPLL will definitely pave way to greater research arena in the field of biomedical field. This ADPLL is a unique combination that combines electronics and biomedical field. The designed ADPLL is itself a broader application to biomedical field that will have a positive impact on the society.

Originality/value

The implementation of open-loop PFD and RO using the capacitive boosting technique is a unique combination. This is comprehended well with frequency controller block that eliminates the usage of TDC and behaves as phase interpolator. The entire design of ADPLL which suits the application of MICS band of frequency has been designed carefully to work at low power.

Details

Circuit World, vol. 47 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 December 1942

THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.

Abstract

THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.

Details

Aircraft Engineering and Aerospace Technology, vol. 14 no. 12
Type: Research Article
ISSN: 0002-2667

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