Series LC Resonator Research Articles

Electrical and plasma characterization of a hybrid plasma source combined with inductively coupled and capacitively coupled plasmas for O atom generation

We developed a hybrid plasma source combined with an inductively coupled plasma (ICP) antenna and a capacitively coupled plasma (CCP) electrode. The ICP antenna and the CCP electrode are connected to a single RF power generator in parallel and a variable capacitor Cv is connected to the ICP antenna in series. The currents flowing through each source and the CCP electrode voltage are measured for analysis of the electrical characteristics, and the ion densities are measured while adjusting the capacitance of the Cv. Interestingly, when a series LC resonance occurs between the inductance of the ICP antenna and the capacitance of the Cv, different trends are observed depending on the discharge mode. In capacitive mode (E-mode), the ion density is minimized and is controlled by the CCP current. On the other hand, in inductive mode (H-mode), the ion density is maximized and is affected by the ICP current. The change of the ion density can be explained by the balance between the total power absorption and power dissipation. It is also in good qualitative agreement with the calculated plasma density from the power balance equation. By adjusting the Cv, linear control of the ion density can be achieved. To evaluate the proposed source in terms of O atom generation, the number density ratio of O atom nO to Ar nAr is obtained by using the optical emission spectroscopy actinometry method. These results show that nO/nAr is controlled. Our source can be applied to plasma processing, in which ion density and O atom generation controls are important factors.

In brief

PAGE 1072 Chinese researchers demonstrate an eight-channel hybrid-integrated laser light source with 100 GHz channel spacing. Side mode suppression ratios of better than 40 dB were obtained via grating couplers under eight-channel simultaneous operation at a continuous wave current of 600 mA and 25°C. PAGE 1056 A robust and efficient long-term tracker based on local feature matching and density clustering is proposed by Chinese researchers for use in UAV-based tracking systems. The tracker used a novel density-based clustering method to locate an occluded target by using local collected features. Experiments show favourable performance of the algorithm compared to other related trackers. Schematic of 8-channel hybrid-integrated laser array. PAGE 1036 A collaboration of researchers from Malaysia and Bangladesh present a single switched-capacitor and series LC resonant converted based active voltage balancing circuit. The balancing circuit directly transfers energy from higher capacitive energy storage cells to lower energy storage cells. Experimental analysis demonstrates the performance of the system. The overall framework of the proposed tracker. The tracking module and re-detection module are shown in blue and red, respectively. PAGE 1091 Researchers from Mexico have developed a new subcarrier allocation scheme for NOMA systems based on the evaluation of the instantaneous behaviour of wireless channels using the condition number of the channel matrix. Simulation results reveal that the proposed scheme increases the total sum rate of the system compared to previous methods. Proposed balancing circuit schematic diagram. PAGE 1065 Researchers from the Republic of Korea present a wideband on-chip Wilkinson power divider (WPD) using lumped-element transition lines with 2-port negative capacitance circuits providing phase response with a positive slope and broadband port impedance. Experimental comparisons against other similar devices show the superior performance of this WPD. Evaluation process. Fabricated WPD chip.

LC resonant circuits based matching networks for continuous mode MMIC power amplifiers

AbstractThis article presents a practical design methodology to construct output matching networks for broadband continuous mode monolithic microwave integrated circuit (MMIC) power amplifiers (PAs). Unlike conventional harmonic manipulation approaches, combinations of parallel and series LC resonant circuits are utilized to build the matching networks as it can generate frequency‐dependent components and locate the varying impedance of continuous mode. With a proper design, the impedance variation in frequency domain can be mapped to the frequency response of the matching network at the fundamental frequency and the second harmonic simultaneously. Matching network design procedures are demonstrated and results show that the frequency response of the network has very good approximation with the desired continuous mode conditions. A prototype PA is implemented on 0.25‐μm gallium nitride (GaN) MMIC process, and tested with both continuous‐wave and modulated signals. Measurement results show 50.82% maximum drain efficiency and 8.5 dB gain can be achieved across the operation bandwidth of 5.4 to 6.4 GHz.

Active voltage balancing circuit using single switched‐capacitor and series LC resonant energy carrier

Single switched-capacitor and series LC resonant converter-based active voltage balancing circuit are presented in this Letter. This converter is proposed to balance the cell voltage in series-connected electrochemical energy storage devices namely battery or supercapacitor. This balancing circuit directly transfers the energy from higher capacitive energy storage cells to lower energy storage cells in the string. It realises the maximum energy recovery and zero voltage gap between the cells and overcomes the drawback of switching loss, conduction loss, balancing time duration, and the voltage difference between the cells of conventional switched-capacitor as well as single LC converter. The details of the balancing circuit operation, theoretical, and mathematical analysis are presented. The experimental result demonstrated that the balancing circuit result where the voltage difference is 451–0 mV in 124 min for two 12 V, 4.5 Ah lead-acid batteries.

Active cell balancing of Li-Ion batteries using single capacitor and single LC series resonant circuit

In this paper a novel single series resonant tank and capacitor converter based voltage balancing circuit for series supercapacitor string and battery cells string is presented. It recognizes the balancing circuit which recovered the maximum energy and zero voltage gap between cells in a series supercapacitor system or battery system. This balancing circuit not only inherits the improvement of conventional single series resonant converter based balancing system, but also recovers the drawback of switching loss, conduction loss and voltage gap between cell strings. All MOSFET switches are controlled by a pair of complementary PWM signals. Also the resonant tank and parallel capacitor operate between the two mode of charging and discharging. This voltage balancing circuit has shown promising result to be used in battery management system.

Analysis and Design of Series LC Resonance-Pulse Based Zero-Current-Switching Current-Fed Half-Bridge DC–DC Converter

This article investigates upon partial resonance in current-fed converter using series LC resonant circuit to attain zero-current-switching (ZCS) of the semiconductor devices. A resonance pulse appears during overlap conduction time of the semiconductor devices causing natural current reduction in an outgoing device to zero before the gating signal is forced-off achieving ZCS commutation of the devices. Soft device turn-off eliminates the turn-off switching losses and more importantly, avoids the traditional requirement of additional snubber to clamp the voltage across the semiconductor devices in current-fed converters. Partial resonance reduces the circulating current and so rms current through the devices limiting the conduction losses. The proposed idea is analyzed and implemented on current-fed half-bridge isolated voltage doubler topology. It has been experimentally demonstrated to achieve wide range ZCS operation along with high efficiency.

Output Voltage Analysis of Inductive Wireless Power Ttransfer with Series LC and LLC Resonance Operations Depending on Coupling Condition

This paper analyzes the output voltage of an inductive wireless power transfer (WPT) depending on coupling conditions. When the optimum efficiency and maximum output power are obtained, it is called critical coupling, so the receiving coil and the transmitting coil should be separated by a certain distance. When the distance between the transmitting coil and receiving coil is very short, it is called over coupling, and output power decreases with the optimal operating state of the critical coupling condition. To design the entire circuit system for the inductive WPT depending on the coupling condition, it is beneficial to analyze the output voltage according to a load variation, an input voltage, and an operating frequency. Therefore, the output voltage depending on the coupling condition in the inductive WPT is analyzed in this paper. The output voltage gain in critical coupling condition is greater than one and is not affected by a load variation by a series LC resonant operation. The reduced output power in an over coupling condition can be recovered by a series LLC resonant operation. In addition, the output voltage gain is almost one and is affected by the load variation in the over coupling condition. A 5W prototype is implemented with the wireless power consortium standard coils and experimental results are shown to verify theoretical analysis and operation.

Research of LC Series Resonant Bidrectional DC/DC Converter

Research of LC Series Resonant Bidrectional DC/DC Converter

Active narrowband filter based on inductance and capacitance for low-frequency applications.

Most analog filter solutions operating in the kilohertz frequency range are based on RC elements. However, it is not possible to design a very narrow filter (high q-factor around 1000) by using this architecture. In this article, we would like to show a filter implemented based on a simple series LC resonance circuit (consisting of just an inductor and a capacitor) and an analog circuit. The designed filter based on these elements can be more selective than a typical active filter based on RC elements (resistor and capacitor). Performed measurements confirmed the correct operation of the filter, where the designed filter q-factor was ∼591 at a resonant frequency of 4.73 kHz.

An 550-650 MHz Digitally-Tunable Bandpass Filter: Design and Implementation

In this paper, a digitally-tunable band-pass filter is designed and implemented for applications of Cognitive Radio in middle Ultra high frequency television band from 550 to 650 MHz. This design is based on the 3th-order Chebyshev filter model in the combination with impedance inverters and series LC resonators, where capacitors are replaced by varactor diodes. The central frequency is tuned by means of a digital control board to adjust DC bias voltages of the diodes. Theoretical analysis, numerical simulation, and hardware implementation are described and carried out. The RF board is fabricated using SMV1736 varactor diodes with FR4-0.8mm material. The results show good match between simulations and measurements in terms of return loss, insertion loss, and fractional bandwidth over the operating range.

Ultrahigh-Sensitivity Microwave Sensor for Microfluidic Complex Permittivity Measurement

The conventional resonant-type microwave microfluidic sensors made of planar resonators suffer from limited sensitivities. This is due to the existence of several distributed capacitors in their structure, where just one of them acts as a sensing element. This article proposes a very high-sensitivity microwave sensor made of a microstrip transmission line loaded with a shunt-connected series LC resonator. A large sensitivity for dielectric loadings is achieved by incorporating just one capacitor in the resonator structure. Applying sample liquids to the microfluidic channel implemented in the capacitive gap area of the sensor modifies the capacitor value. This is translated to a resonance frequency shift from which the liquid sample is characterized. The sensor performance and working principle are described through a circuit model analysis. Finally, a device prototype is fabricated, and experimental measurements using water/ethanol solutions are presented for verification of the sensing principle.

The equivalent circuit imitating wave scattering by arrays of split-ring resonators

The scattering of waves by a periodic chain of series resonant LC circuits in a two-dimensional lattice of lumped elements is considered, that imitates the scattering of electromagnetic waves by a periodic lattice of split-ring resonators. Using the translation symmetry of this chain we transformed the scattering problem into the problem of wave propagation along the strip with a single LC circuit. This problem was solved analytically presenting the transmittance as a sum of partial transmittances, corresponding to the frequency mini-bands of the strip. It is shown that the transmittance as a function of the incident wave frequency demonstrates two types of resonances with different resonant frequency dependence on the distance between neighbouring LC circuits.

Possibility of Acoustic Resonance in Hair Cells in Human's Auditory System.

Apart from Von Békésy's traveling wave theory, this paper introduces our new comprehension on auditory system based on acoustic resonance in hair cells. Focusing on a rootlet inductance L and a membrane capacitance C of the hair cell, a real-sized cell model is designed so as to form a series LC resonant circuit for the incident soundwaves. In simulation, acoustic resonance is observed successfully at 1120 Hz together with 148-times sound pressure enhancement inside the cell. This model is useful to explain OAE responses, frequency shifts of absolute pitch for aging, pure-tone tinnitus, and even apoptosis of outer hair cells by huge sound exposure.

A Series Resonant Energy Storage Cell Voltage Balancing Circuit

A novel cell voltage equalizer using a series LC resonant converter is proposed for series-connected energy storage devices, namely, battery or super (or ultra)-capacitor cells. The proposed circuit is an active voltage equalization circuit for energy storage devices that is low cost, small in size, and equalizes the voltages quickly. Compared to the state-of-the-art solutions, the proposed series LC resonant circuit eliminates the complexity of multiwinding transformers, and it can balance series-connected energy storage devices in a short time by transporting energy successively between the cells having highest voltage difference. The detailed circuit operation and theoretical analysis are provided. Simulation and experimental results are presented to demonstrate the voltage equalization process from an initial voltage difference of 527 mV to a final difference of 10 mV in 900 s for three series-connected supercapacitor cells.

A SiGe BiCMOS Concurrent K/V Dual-Band 16-Way Power Divider and Combiner

A new dual-band 16-way power divider and combiner on a 0.18- ${\mu }\text{m}$ SiGe BiCMOS process that works concurrently over 18–26 GHz (K-band) and 57–64 GHz (V-band) is presented. The 16-way K/V dual-band power divider integrates a two-way K/V dual-band Wilkinson-based power divider with a high-pass filter and multiple broad-band two-way lumped-element and transmission-line Wilkinson power dividers. The two-way dual-band power divider is designed by employing a slow-wave transmission line and two shunt-connected series LC resonators in each arm, leading to miniaturization and low loss with dual-band transmission in K- and V-band, decent return losses, and good isolation of larger than 20 dB over the dual-band. The developed 16-way K/V dual-band power divider possesses good performance over the dual-band. Specifically, it achieves measured insertion losses of 18.4 and 21 dB at 24 and 60 GHz, respectively, with good return losses. Furthermore, it also exhibits measured isolation larger than 20.1 and 17.7 dB between any two output ports at 24 and 60 GHz, respectively.

An analysis of a DGS‐inserted stub resonator and its application to an optimum BSF

AbstractA novel defected ground structure (DGS)‐inserted stub (DIS) resonator is proposed. The proposed DIS resonator features a typical dumbbell‐shaped DGS inserted into an conventional open‐circuited stub (OCS) resonator, and it is modeled by a series LC resonator. The inserted DGS can suppress a harmonic and extend an upper passband. Therefore, the proposed DIS resonator to generate a resonance at 2.0 GHz keeps the upper passband up to 8.0 GHz or higher, while the OCS resonator with the same resonance gives rise to the harmonic at 5.78 GHz. These properties are investigated through EM simulation. Moreover, in order to verify the applicability of the proposed DIS resonator to microwave filters, two optimum bandstop filters (BSFs) with the same stopband at 2.0 GHz using the proposed DIS and OCS resonators are fabricated and measured, respectively. Compared to the optimum BSF using the OCS resonator, the optimum BSF using the proposed DIS resonator shows two notable improvements: a 50% increase in the upper passband and a 15% reduction in the size.

Modeling and Optimization of Inductively Coupled Wireless Bio-Pressure Sensor System Using the Design of Experiments Method

This paper presents an approach for modeling and design of inductively coupled wireless bio-pressure sensor system for chronic intracardiac pressure monitoring. Making use of recent advances in microelectromechanical systems and semiconductor technology, bio-pressure sensor is developed as a series LC resonant circuit with a featured pressure-dependent capacitance working at the medical implant communication service band of 402–405 MHz for wireless sensing without power consumption. The microfabricated sensor consists of a planar spiral gold (Au) coil, a series capacitor, an SU-8-based frame structure, and an encapsulated bio-compatible PDMS membrane. Bio-pressure sensor is designed with a small footprint of 3.2 mm $\times $ 3.2 mm for reducing the bleeding and infection risks in surgery. With a limited footprint and desired working frequency, there are many mutually dependent geometry parameters with numerous combined groups of values involved in the full optimization of the system. In order to maximize the performance of system under the design requirements, RF characteristics that affect inductive sensitivity and pressure sensitivity are theoretically analyzed first, and then design of experiments method is applied to model and optimize 3-D electromagnetic models of sensor and sensor system on the derived RF characteristics. The large number of combined groups of values in factorial simulations is thus reduced to a few performance-related design factors. By monitoring the induced peak impedance of the readout coil, the pressure-dependent resonant frequency of the sensor can be detected and measured. The experimental results show that the optimized wireless sensor system has a relatively high average pressure sensitivity of 5.3 KHz/mm Hg at a telemetry distance of 10 mm demonstrating its potential for intracardiac pressure monitoring.

Reconfigurable resonant module for multi‐band antenna design

Novel resonant modules for constructing multi-band mobile antennas are proposed in this study. The basic configuration of the module, named as the prototype module, is designed based on a series LC resonant circuit. By adding a varactor to the module, it can be transformed into a reconfigurable module. By introducing an extra resonant mode with capacitive coupling to enhance the bandwidth, a wide-band module can be obtained. These modules have different frequency ranges, and can be combined into multi-band antennas for various applications. The proposed modules are demonstrated by constructing a 4G-LTE antenna. The reconfigurable module, which is of 20 × 20 mm2, is designed to switch between LTE700 (698–787 MHz) and GSM850 (824–960 MHz) bands. The wide-band module, which is of 10 × 10 mm2 and 49.3% bandwidth, is designed for GSM1800/GSM1900/UMTS/LTE2300/LTE2500 (1.71–2.59 GHz) applications. All designs have been realised and measured for validation. The proposed antenna modules, which are simple and convenient to use, can provide flexibility, especially in antenna deployment, in multi-band mobile antenna designs.

Holistic design strategy for high‐selectivity low‐loss integrated millimetre‐wave image‐reject filters

To alleviate practical limitations in the design of millimetre-wave on-chip image-reject filters, systematic design methodologies are presented. Three low-order filters with high-selectivity and low-loss characteristics are designed and compared. Transmission zeroes are created by means of a quarter-wave transmission line (filter 1) and a series LC resonator (filters 2 and 3). Implemented on silicon germanium, the filters occupy 0.125, 0.064 and 0.079 mm2 chip area including pads. The measured transmission losses across 81–86 GHz E-band frequency range are 3.6–5.2 dB for filter 1, 3.1–4.7 dB for filter 2 and 3.6–5 dB for filter 3 where rejection levels at the image band are >30 dB.

An on‐wafer embedded passive device using chip‐in‐substrate packaging technology

ABSTRACTIn this article, a new packaging technology called chip‐in‐substrate packaging (CiSP) technology, which embeds passive components such as inductors and capacitors on silicon substrates, is arranged for a three‐dimensional structure. As the parasitic capacitance of the inductors and capacitors are increased by CiSP, a lower self‐resonance frequency compared with bare chips can be avoided using a printed circuit board with low thickness and low permittivity. To verify CiSP on the circuit level, a diplexer circuit is simulated from measured components and is composed of two series LC resonators to apply a GSM band (880–960 MHz) and a DCS band (1.71–1.88 GHz). An insertion loss of 0.76 dB at 0.96 GHz for GSM and 0.772 dB at 1.71 GHz for DCS are realized by CiSP technology. Moreover, the minimum rejections of 19.1 dB at 1.71 GHz for GSM and 20.8 dB at 0.96 GHz for DCS are realized with the maximum rejections for the DCS and GSM bands of 37.6 and 33.7 dB, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2060–2067, 2015