Antenna For Biomedical Applications Research Articles

MULTIBAND FLEXIBLE ULTRA-WIDEBAND ANTENNA FOR WEARABLE ELECTRONICS AND BIOMEDICAL APPLICATIONS

This article proposes a flexible ultra-wideband (UWB) antenna for wearable electronics and biomedical applications. The antenna presented for this work is fabricated on a Kapton polyimide (PI) substrate, and the operating frequency ranges from 2.4 GHz to 7.1 GHz. The footprint of the proposed antenna is 35 × 45 mm with an elliptical radiating element fed by coplanar waveguide (CPW), which achieves improved impedance matching characteristics. The choice of substrate, design constraints, fabrication process, and bending test of the proposed flexible UWB antenna are explained in detail in this paper. A comparative study on the choice of substrate is performed and the Kapton PI is chosen as the substrate material, which makes the antenna less susceptible to degradation in antenna performance that arises due to bending effects. The measurement and simulated results of the fabricated antenna show a good degree of agreement. The return loss performance of the proposed antenna is greater than -10 dB in all the operating bands with improved gain and directivity. The flexible nature with multiple frequency bands of operation and good bending performance makes the proposed antenna appropriate for wearable electronic and biomedical applications.

Wearable Polarization Conversion Metasurface MIMO Antenna for Biomedical Applications in 5 GHz WBAN

This paper presents a wearable metasurface multiple-input multiple-output (MIMO) antenna for biomedical applications in a 5 GHz wireless body area network (WBAN) with broadband, circular polarization (CP), and high gain. The physical properties of the MIMO antenna element and the principles of polarization conversion are analyzed in-depth using characteristic mode analysis. For the proposed MIMO antenna, the measured -10 dB impedance bandwidth is 34.87% (4.76-6.77 GHz), and the 3 dB axial ratio bandwidth is 22.94% (4.9-6.17 GHz). By adding an isolation strip, the measured isolation of the two antenna elements is greater than 19.85 dB. The overall size of the MIMO antenna is 1.67λ0 × 0.81λ0 × 0.07λ0 at 5.6 GHz, and the maximum gain is 7.95 dBic. The envelope correlation coefficient (ECC) is less than 0.007, with the maximum diversity gain greater than 9.98 dB, and the channel capacity loss is less than 0.29 b/s/Hz. The specific absorption rate (SAR) of the wearable MIMO antenna is simulated by the human tissue model, which proves that the proposed antenna conforms to international standards and is harmless to humans. The proposed wearable metasurface MIMO antenna has CP, broadband, high gain, low ECC, and low SAR, which can be used in wearable devices for biomedical applications.

A compact implantable MIMO antenna with high isolation and wide bandwidth

ABSTRACT A compact wideband three-unit implantable multiple-in-multiple-out (MIMO) antenna for biomedical applications is proposed in this paper. By loading a “Y” slots on the radiation patch, and a metallized via between the radiation patch and the ground plane, they are jointly designed to reduce the Q value of the antenna unit and improve its bandwidth. At same time, three “wolf-teeth club “ slots with filtering characteristics are introduced into the ground plane to isolate the coupling of ground surface current at feed ports of antenna units, so as to improve the isolation between feed ports. The 10 dB bandwidth of the MIMO antenna unit is 1.21 GHz-1.66 GHz, covering the commonly used Wireless Medical Telemetry Services (WMTS) band (1.427–1.432 GHz). And the isolation between units is more than 29 dB in the whole 450 MHz bandwidth, among which the isolation in WMTS band are more than 31 dB. Compared with other implantable MIMO antennas, this design not only integrates more MIMO antenna units in a small area but also each MIMO unit has broadband characteristics.

Improvement of Novel Wearable Antenna for Biomedical Applications and Investigations On Their Concert Under Flexible Condition

Improvement of Novel Wearable Antenna for Biomedical Applications and Investigations On Their Concert Under Flexible Condition

Improvement of Novel Wearable Antenna for Biomedical Applications and Investigations On Their Concert Under Flexible Condition

Improvement of Novel Wearable Antenna for Biomedical Applications and Investigations On Their Concert Under Flexible Condition

Effect of A Superstrate on On-Head Matched Antennas for Biomedical Applications

The effect of using a superstrate dielectric layer on an on-head matched antenna for biomedical diagnosis applications is investigated. Two on-head matched antennas are considered with different length meandered lines ensuring operation around 0.9 GHz frequency. The first antenna’s conductive radiating structure is in direct contact with the head phantom, whereas the second one utilises a 0.5 mm thick superstrate layer on top of the conducting layer as a buffer. The lateral dimensions of both antennas are held constant at 30 × 30 mm2. The electric and magnetic field distribution is analysed and the power penetration, 50 mm inside the head phantom, is derived from the electromagnetic field surrounding the antennas. Both homogeneous and inhomogeneous head phantoms are considered while evaluating the antennas in terms of their reflection coefficient, current distribution, electric field, magnetic field, specific absorption rate (SAR) and power penetration inside the head. The antennas are fabricated and measured utilizing an inhomogeneous phantom to validate the proposed performance improvement using a superstrate. It is shown that the superstrate antenna achieves a ~8 dB increase in power penetration inside the head phantom along with a 0.0731 W/kg decrease in SAR compared to the antenna without a superstrate.

On body e-shaped patch antenna for biomedical application

An E-shaped micro strip patch antenna is designed and analyzed in this paper which operates in MICS (402.0-406.0MHz) band. The Performance has been observed on a body of human phantom model as well as in free space with different conducting material for the designed antenna. The height of this antenna is taken 1.5mm from the ground plane. At resonance frequency of 405 MHz the S11 parameter is obtained in free space is -23.26dB for conducting material of aluminum and -17.96dB is measured on human phantom body at 405 MHz of resonance frequency. FR4 is used as substrate material. The Specific Absorption Rate (SAR) is found to be 0.3562 W/kg by placing the antanna on human phantom model. VSWR and directivity has been analyzed also.

Implantable CPW fed M Shaped Antenna for Biomedical Applications

Implantable medical device has become very popular in medical sector for proper diagnosis and treatment. If, this devices are wireless, then it will very effective for remote communication. For this wireless communication, antenna is a suitable thing. So, this paper presents the design Implantable CPW fed M-shaped antenna for biomedical applications. Coplanar waveguide fed technique is used with ground plane in this antenna. The antenna is designed by Alumina ceramic (Al2O3) substrate and Copper ground plane with dimensions (8mm × 7mm × 0.85mm) and Silicon material of 0.1mm thickness is used as a coating for human body safety. This antenna works under 2.42 GHz resonate frequency of ISM band (2.40-2.48 GHz). The bandwidth percent of the antenna at -10dB is 7.66%. The return loss characteristic of the antenna is -56.96 dB. Based on the conductivity and permittivity of different tissue (such as: Muscle, Fat. Skin) a simple 3D human body phantom structure is designed for implantation of CPW fed antenna. The antenna is designed and simulated with the help of CST software. The antenna parameters such as: Return loss, Smith Chart, VSWR, Gain, SAR have been discussed in the paper.

Efficient compact monopole antenna for on‐body applications

AbstractThis research paper presents the design and implementation of low profile printed monopole antenna for Bio medical applications. The proposed antenna is designed for industrial, scientific, and medical frequency band (2.4–2.48 GHz). Four different patch geometries are considered and their performance is analyzed. The various parameter studies on ground length and slot width is performed and the precise dimensions are chosen. The slotted geometry along with stepped ground plane increases the current path and reduces the antenna size. To alleviate the impedance matching, proposed structure is endowed with stub tuning and hence minimum return loss −31 dB is attained. The proposed antenna is built on FR4 substrate and overall dimension (l, w, h) of this antenna is 20 mm × 20 mm × 1.6 mm. Antenna simulations are performed using ADS. The performance parameters of the proposed antenna is examined through simulations and verified with measured data. The measured result shows good concurrence with the simulated results. The proposed antenna exhibits good isolation of −35 dB between co‐ and cross‐polarization. It has stable gain of 2.92 dBi over the frequency range of 2.4–2.48 GHz and achieves 98.6% radiation efficiency.

Design and simulation‐based performance evaluation of a miniaturised implantable antenna for biomedical applications

Biomedical telemetry is an emerging field of research which enables the formation of a transmission link from inside a living body to an external device. Implantable medical devices are now one of such valuable advancement in the field of biomedical telemetry. Implantable patch antennas are gaining attention and are becoming more of a choice for implantable medical devices that uses mostly RF telemetry. In this work, a state-of-the-art design for a rectangular implantable flexible patch antenna is proposed. The operation band for the antenna is chosen in the Industrial, Scientific and Medical (ISM) band (2.4-2.4835 GHz). The tiny dimension of the antenna, including the 9.45 μm thickness of the patch itself allows the antenna to be highly flexible and provides excellent results even at extreme bent conditions. For simulation environment, a three-layer human tissue model was used, where the antenna was encapsulated between the fat and skin layer. CST Microwave Studio was chosen to design and simulate the antenna. Several performance parameters were simulated, such as the operating resonant frequency, the return loss, radiation pattern, specific absorption rate and also sensitivity of the antenna when introduced to bending.

Design and Performance Measurement of a Miniaturized Implantable PIFA Antenna for Biomedical Applications

An implantable PIFA (Planar Inverted F Antenna) antenna for biomedical applications is proposed in this study. The main notability of this design refers to its subtle dimension, flexibility and subordinate thickness that makes it perfectly suitable for implementing inside human or animal tissues for Wireless Body Area Networks (WBAN). The antenna is aimed to operate in the Industrial, Scientific and Medical (ISM) band (2.4–2.4835 GHz). The thickness of this antenna is only 0.735 mm, which implies that this antenna is suitable to perform under bent conditions. The antenna offers a compact design with a dimension of 9.48 mm × 7.8 mm × .735 mm (54.348 mm3). Copper and Rogers R03010 are chosen as the patch material and substrate material accordingly. The antenna is encapsulated inside biocompatible material Rogers R03010 for safety concern inside skin or muscle tissues. Several types of analysis and performance measurement of this antenna have been done by using CST Microwave studio in both planar and bent conditions by maintaining the electrical properties of human skin tissues. Specific Absorption Rate (SAR) and thermal loss are evaluated to comply with the antenna safety issues. For proving biocompatibility and versatility of this antenna, performance analysis by changing different patch materials and substrate materials have been done after putting the antenna inside different human tissue models. Finally, the antenna is fabricated on to a FR4 substrate and its performance is measured using Agilent Technologies E5071C Network Analyzer.

Antennas for biomedical applications

Biomedical engineering today holds a prominent place as a means of improving medical diagnosis and treatment, and as an academic discipline. Today glucose monitoring, insulin pumps, deep brain simulations and endoscopy are a few examples of the medical applications that can take advantage of remote monitoring system and body implantable unit. Body implantable devices are widely researched for humans, in the applications such as monitoring blood pressure and temperature, tracking dependent people or lost pets, wirelessly transferring diagnostic information from an electronic device implanted in the human body for human care and safety, such as a pacemaker, to an external RF receiver. Antennas can be implanted into human bodies or can just be mounted over the torso (skin-fat-muscle) to form a bio-communication system between medical devices and exterior instruments for short range biotelemetry applications. In addition to the clear benefits to the healthcare system provided by body implanted devices, economical aspects are also relevant. Remote monitoring systems facilitate the diagnosis of diseases and favor the hospital at home by reducing the hospitalization period.

Simplified nonresonant perturbation method of measuring aspects of performance of UHF and microwave antennas for biomedical applications

A simplified form of the nonresonant perturbation technique is described which is suitable for measuring aspects of the performance of commonly used types of UHF and microwave antenna for biomedical radiometry and hyperthermia induction.

Microstrip microslot antennas for biomedical applications: frequency analysis of different parameters of this type of applicator

A new type of microstrip slot applicator with a circular aperture has been designed for clinical applications in microwave hyperthermia treatment and microwave radiometry for temperature measurement. We present the frequency study of the microwave performance of this new applicator, measured on a lossy medium according to its parameters (substrate, circular aperture etc.).