GHz Industrial, Scientific And Medical Research Articles

Analysis of muscle implanted antenna performance with the variation of implantation depth

Abstract Implantation depth of Implantable Medical Devices (IMDs) is an important factor of communication quality between implantable antennas in IMDs and external devices. Therefore, it is required to study the effect of implantation depth on implantable antenna performance. In this article, dependence of resonant frequency and scattering parameters of a two-antenna system where one miniaturized meander-line antenna is placed within human muscle tissue layer operating at 2.45 GHz ISM (industrial, scientific and medical) band and a rectangular patch antenna placed outside human body, are tested. Here 15 values of implantation depth ranging over 5–35 mm inside muscle layer are taken and for each case resonant frequency and scattering parameters (S 11 and S 21) of the system are recorded. Statistical analysis has been performed to observe how these performance parameters are dependent on depth of implantation which may be varied at the time of surgery.

A High Performance All-Textile Wearable Antenna for Wristband Application.

A compact, conformal, all-textile wearable antenna is proposed in this paper for the 2.45 GHz ISM (Industrial, Scientific and Medical) band. The integrated design consists of a monopole radiator backed by a 2 × 1 Electromagnetic Band Gap (EBG) array, resulting in a small form factor suitable for wristband applications. An EBG unit cell is optimized to work in the desired operating band, the results of which are further explored to achieve bandwidth maximization via floating EBG ground. A monopole radiator is made to work in association with the EBG layer to produce the resonance in the ISM band with plausible radiation characteristics. The fabricated design is tested for free space performance analysis and subjected to human body loading. The proposed antenna design achieves bandwidth of 2.39 GHz to 2.54 GHz with a compact footprint of 35.4 × 82.4 mm2. The experimental investigations reveal that the reported design adequately retains its performance while operating in close proximity to human beings. The presented Specific Absorption Rate (SAR) analysis reveals 0.297 W/kg calculated at 0.5 W input power, which certifies that the proposed antenna is safe for use in wearable devices.

Cavity Backed Slot Antenna Fed by a Stripline with SIW Structure and Vertical Coaxial Transition for Microwave Solid-State Heating Applications

This paper presents a new approach to feed multimode cavities used as microwave applicators for industrial and domestic microwave ovens using solid-state sources operating in the 2.45 GHz ISM (Industrial, Scientific and Medical) band (commonly used for industrial microwave applications). The feeding structure consists of a slot on the top side of the applicator cavity. The slot is fed by a shielded asymmetric stripline with a Substrate Integrated Waveguide structure (to preserve the stripline Transversal Electro-Magnetic (TEM) operation within the shield) and is N-connectorized. A first design of the antenna was obtained using state-of-the-art antenna theory assuming free-space radiation. Then, it was refined using a commercial simulation tool based on the Finite Element Method in the frequency domain to achieve VSWR values lower than 1.5 in the source bandwidth (from 2.42 to 2.48 GHz) when the antenna radiates into the applicator cavity. The design parameters of all the components making up this feeding structure are discussed throughout the paper. A prototype was built and measured in the laboratory. The experimental results are presented at the end of the paper along with the simulated ones, showing a very good agreement.

Projeto de uma Antena Planar Dipolo Curvado para Aplicação na Comunicação da Indústria 4.0

This article contemplates a qualitative analysis of the operation of a Curved Planar Dipole Antenna, of the line meander type and its applicability in the Internet of Things (IoT). Technology originated in the midst of the intelligent technological development of the current period, considered as the Fourth Industrial Revolution or Industry 4.0 and marked by the improvement of systems that promote automation of tasks, control and data sharing in wireless networks in real time. IoT is associated with facilitated connectivity between the physical and digital world through the internet or miniaturized elements, generating optimization in the manufacturing and routine processes. Particularly, planar antennas stand out in this regard, as they provide the transmission or reception of signals by means of electromagnetic waves, have low manufacturing cost, small volume and weight and are built according to the desired purpose. Thus, the proposed objective was to design, simulate and analyze a meander line antenna that operates in the 2.4GHz ISM (Industrial, Scientific and Medical) frequency range, verifying its effectiveness in the IoT. However, with the aid of the HFSS® software, satisfactory results regarding the resonance frequency and radiation diagram of the studied device are obtained in a computer simulation environment.

Ultra-low-power wideband NMOS LC-VCO design for autonomous connected objects

In this paper, a fully integrated sub threshold LC voltage controlled oscillator (VCO) is presented. A design methodology is also proposed to find the optimal parameters lowering the power consumption. This methodology has been applied to design oscillators for different frequency bands. Furthermore, an adaptive body biasing technique has been used to improve the startup constrains and allows a high immunity to PVT (process, voltage and temperature) variations. A VCO operating in 5 GHz ISM (Industrial, Scientific and Medical) band has been realized with the proposed methodology in 0.13 μm CMOS. It consumes only 468 μW from 0.39 V supply voltage. This makes it possible to meet the required specifications of autonomous connected objects and IoT applications. The measured oscillation frequency can be tuned from 5.14 to 5.44 GHz. The obtained phase noise is approximately equal to − 112 dBc/Hz in post-layout simulation (PLS) and − 104.5 dBc/Hz in measure.

Design Architectures of the CMOS Power Amplifier for 2.4 GHz ISM Band Applications: An Overview

Power amplifiers (PAs) are among the most crucial functional blocks in the radio frequency (RF) frontend for reliable wireless communication. PAs amplify and boost the input signal to the required output power. The signal is amplified to make it sufficiently high for the transmitter to propagate the required distance to the receiver. Attempted advancements of PA have focused on attaining high-performance RF signals for transmitters. Such PAs are expected to require low power consumption while producing a relatively high output power with a high efficiency. However, current PA designs in nanometer and micrometer complementary metal–oxide semiconductor (CMOS) technology present inevitable drawbacks, such as oxide breakdown and hot electron effect. A well-defined architecture, including a linear and simple functional block synthesis, is critical in designing CMOS PA for various applications. This article describes the different state-of-the art design architectures of CMOS PA, including their circuit operations, and analyzes the performance of PAs for 2.4 GHz ISM (industrial, scientific, and medical) band applications.

A Modified Meander Line Microstrip Patch Antenna With Enhanced Bandwidth for 2.4 GHz ISM-Band Internet of Things (IoT) Applications

Internet of Things (IoT) based application requires integration with the wireless communication technology to make the application data readily available. In this paper, a modified meander shape microstrip patch antenna has been proposed for IoT applications at 2.4 GHz ISM (Industrial, Scientific and Medical) band. The dimension of the antenna is 40×10×1.6 mm 3 . The antenna design is comprised of an inverse S-shape meander line connected with a slotted rectangular box. A capacitive load (C-load) and parasitic patch with the shaped ground are applied to the design. Investigations show that the antenna designed with an inverse S-shape patch and connecting rectangular box in the microstrip line has a higher efficiency and gain compare to the conventional meander shape antenna. The C-load is applied to the feed line to match the impedance. Moreover, parametric studies are carried out to investigate the flexibility of the antenna. Results show that, the gain and efficiency can be improved through adjusting the rectangular box with applying parasitic element and the shaped ground. The parasitic element has high impact on the bandwidth of the antenna of 12.5%. The finalized antenna has a peak gain of -0.256 dBi (measured) and 1.347 dBi (Simulated) with 79% radiation efficiency at 2.4 GHz. To prove the efficiency and eligibility in IoT applications, the measurement of the power delivered and received by the antenna at 2.4 GHz is performed and compared with the results of a dipole antenna. The antenna is integrated with 2.4 GHz radio frequency module and IoT sensors to validate the performance. The antenna novelty relies on the size compactness with high fractional bandwidth that is validated through the IoT application environment.

Development of a wideband microwave reactor with a coaxial cable structure

A wideband microwave reactor with an output that includes the 915MHz and 2.45GHz ISM (Industrial, Scientific and Medical) bands was designed and fabricated. The reactor structure incorporated a coaxial cable, and a liquid sample was placed in the space between the inner and outer conductors. Insertion of a truncated cone-shaped polytetrafluoroethylene (PTFE) device was used as a method to reduce microwave reflection over a wide frequency range. The reactor had a volume of 360ml and was designed employing a 3D electromagnetic simulation. Ultrapure water and a 0.1M NaOH solution were selected as the liquid samples and experimentally measured permittivity data for these liquids were employed during the reactor simulations. The measured reflection ratio exhibited the same trend as the simulation results between 800MHz and 2.7GHz. The reflection ratio was especially low in the case of the NaOH solution (less than 2%), although this value increased to more than 40% upon removal of the PTFE insert. Microwave heating tests demonstrated that this reactor was able to heat liquid samples at 915MHz, 1.7GHz and 2.45GHz, with estimated microwave absorption efficiencies varying between 28% and 66% depending on the frequency, sample type and heating duration. The reflection ratio and heating data demonstrated that this reactor functioned over a wide frequency range between 800MHz and 2.7GHz. A non-uniform temperature distribution in the sample remained a challenge that must be addressed in future work.

TelG Mote: a green wireless sensor node platform for smart home and ambient assisted living

The wireless sensor network (WSN) consists of sensor nodes that interact with each other to collectively monitor environmental or physical conditions at different locations for the intended users. One of its potential deployments is in the form of smart home and ambient assisted living (SHAAL) to measure patients or elderly physiological signals, control home appliances, and monitor home. This paper focuses on the development of a wireless sensor node platform for SHAAL application over WSN which complies with the IEEE 802.15.4 standard and operates in 2.4 GHz ISM (industrial, scientific, and medical) band. The initial stage of SHAAL application development is the design of the wireless sensor node named TelG mote. The main features of TelG mote contributing to the green communications include low power consumption, wearable, flexible, user-friendly, and small sizes. It is then embedded with a self-built operating system named WiseOS to support customized operation. The node can achieve a packet reception rate (PRR) above 80 for a distance of up to 8 m. The designed TelG mote is also comparable with the existing wireless sensor nodes available in the market.

Design of Hexagon Shape Bow-Tie Patch Antenna for Implantable Bio-Medical Application

In this paper presents the patch antenna in the shape of hexagon bow-tie antenna for implantable bio-medical application in the frequency range of 2.4–2.48GHz ISM (industrial, scientific and medical) band. The patch antenna designed with CPW feed for high frequency response. The proposed system is designed with the material of Alumina ceramic substrate (Al2O3), the value of dielectric constant is 9.8 with thickness of 1mm. The total size of the antenna is 10*10*1 mm. The main advantage of proposed system is it consumes very low size and the accuracy of the system is increased. The designed antenna is analyzed with human tissues like skin, fat and muscle and the parameters of the antenna like return loss, VSWR, radiation pattern and gain etc, are measured. The return loss of proposed antenna is-29dB achieved. So the proposed hexagon shape bow-tie antenna is used for several implantable applications.

Performance Evaluation of the Effect of Noise Power Jammer on the Mobile Bluetooth Network

Network jammers can uncover the reliability of the wireless networks, where the position of the jammer node permit the network to cope with jamming leveraging varieties of defence strategies. Wireless Bluetooth network is a short range network, where the Bluetooth transceiver is operating in the 2.4 GHz ISM (industrial, scientific and medical) radio band, and a special type of frequency hopping pattern was included with the specification of the Bluetooth technology to offer the necessity requirement for the matching Radio Frequency RF channels. This paper calculates and evaluates the effect of noise power jammer and follower jammer on the Personal Area Network (PAN) Bluetooth network. The results prove that the effect on the Bluetooth network depends on many factors such as power density, distance and immunity technique, which is used in many Bluetooth networks.

Design and Analysis of a Multiple-Input Receiver for Mimo Wireless Applications

In this article, we present multiple-input receiver architecture for MIMO (Multiple-Input Multiple-Output) wireless communication applications. The proposed implementation is provided by a defined number of identical receiver units that are fed by a RF modulated signal on specific carrier frequency, power strength and initial phase. These units carry out the corresponding amplification, filtering and demodulation procedures. Details on design and implementation of this Printed-Circuit-Board are introduced and further discussed. Experimental results are also presented, allowing the validation of investigation on the performance of the current receiver architecture. Besides, these measurements indicate that the proposed device, combining with a suitable antenna array, provides a versatile receiver platform for baseband signal processing. The incoming RF modulated signals have frequencies on the range of 2.4 GHz, several phases, magnitudes and modulation modes. From these, it seems that the proposed receiver implementation supports MIMO communication and multiple port channel characterization applications at 2.4 GHz ISM (Industrial, Scientific and Medical) band.

Topology bandpass filters in coplanar strip lines

We report a new bandpass filter on coplanar strip (CPS) lines for RF and microwave applications. The filter is implemented as electrode topology on the CPS electrodes. The topology consists of basic electrode patterns that emulate inductors and capacitors in a two-port filter section. In the design process, equivalent circuit model is used to identify the initial topology, which is then fine tuned using full wave analysis. The bandpass filter is very compact in size and planar in structure. It does not use quarter-wavelength sections, vias, or bonding wires. It can be fabricated without incurring additional cost. Bandpass filters for the 2.4 GHz ISM (Industrial, Scientific, and Medical) band were designed, fabricated, and measured. The measurement responses agree well with the full-wave simulation results. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.

Sendust와 Mn-Zn Ferrite를 이용한 PCB로부터의 전자파 방사 억제용 전파흡수체 개발

본 논문에서는 Sendust와 Mn-Zn ferrite를 이용하여 2.4 GHz ISM 대역 PCB 노이즈 제거용 전파흡수체를 설계 및 제작하였다. Sendust와 Mn-Zn ferrite를 바인더인 CPE와 혼합하여 조성비별 전파흡수체 샘플을 제작하였고, 이를 분석한 결과 최적의 조성비가 Sendust : Mn-Zn ferrite : CPE=70:5:20 wt.%임을 확인하였다. 전파흡수체 샘플로부터 계산되어진 재료 정수를 이용하여 두께에 따른 흡수능의 변화를 시뮬레이션 하였으며, 시뮬레이션 결과를 토대로 전파흡수체를 실제작하여 전파 흡수능을 비교, 분석하였다. 그 결과, 시뮬레이션 결과와 실측정 결과는 잘 일치하였으며, 중심 주파수 2.4 GHz에서 흡수능 5.4 dB, 1.4<TEX>$\sim$</TEX>4.1 GHz 대역에서 3 dB 이상의 흡수능을 보였으며, 이때 두께는 0.85 mm이었다. In this paper, we designed and fabricated the EM wave absorber consists of Sendust and Mn-Zn ferrite for suppressing EM wave noise from PCB in ISM(Industrial, Scientific and Medical) band of 2.4 GHz. We fabricated several samples in different ratios of Sendust to Mn-Zn ferrite with CPE(Chlorinated Ploy-ethylene) as binder and confirmed that optimum composition ratio of absorbing materials was Sendust. Mn-Zn ferrite : CPE=70:5:20 wt.%. The absorbing abilities were simulated according to different thickness of EM wave absorber as the function of material constants calculated by measured data. Measured absorption ability was analyzed and compared with simulated result. The simulated result agree well with the measured ones. As a result, the developed EM wave absorber with thickness of 0.85 mm has absorption ability of 5.4 dB at 2.4 GHz and over 3 dB in frequency rage of 1.4<TEX>$\sim$</TEX>4.1 GHz.

Compact bandpass filters in coplanar strip lines

The authors describe a compact bandpass filter design implemented in asymmetric coplanar strip lines. For initial demonstration, it was built on print circuit boards using modified two-pole Butterworth bandpass filter topology. The novel filter design does not use bonding wires, vias or any interconnecting structure. It is not based on quarter wavelength sections either. It uses the creation of an electrode pattern on the coplanar strip electrodes to emulate an equivalent circuit. The pattern is fine-tuned using full-wave simulations. Bandpass filters for 2.4 GHz ISM (Industrial, Scientific and Medical) and 5.15–5.85 GHz UNII (Unlicensed National Information Infrastructure) bands were designed, fabricated and measured. Measurement responses agree well with full-wave simulation results. The electrode pattern can be scaled for different centre frequency and improved with fine-tuning procedure. For chip-level implementation, the filter size can be greatly reduced because of much smaller minimum electrode width.