scholarly journals Optimization-Based Antenna Miniaturization Using Adaptively Adjusted Penalty Factors

Electronics ◽  
2021 ◽  
Vol 10 (15) ◽  
pp. 1751
Author(s):  
Marzieh Mahrokh ◽  
Slawomir Koziel

The continuing trend for miniaturization of electronic devices necessitates size reduction of the comprising components and circuitry. Specifically, integrated circuit-antenna modules therein require compact radiators in applications such as 5G communications, implantable and on-body devices, or internet of things (IoT). The conflict between the demands for compact size and electrical and field performance can be mitigated by means of constrained numerical optimization. Evaluation of performance-related constraints requires expensive electromagnetic (EM) analysis of the system at hand; therefore, their explicit handling is inconvenient. A workaround is the penalty function approach where the primary objective (typically, antenna size) is complemented by additional terms quantifying possible constraint violations. The penalty coefficients that determine contributions of these terms are normally adjusted manually, which hinders precise control over antenna performance figures and often leads to inferior results in terms of achieved miniaturization rates. This paper proposes a novel algorithm featuring an automated adjustment of the penalty factors throughout the optimization process. Our methodology is validated using three broadband antenna structures. The obtained results demonstrate that the presented adaptive adjustment permits a precise control over the constraint violations while leading to better miniaturization rates as compared to manual penalty term setup.

Author(s):  
Asmaa Zugari ◽  
Wael Abd Ellatif Ali ◽  
Mohammad Ahmad Salamin ◽  
El Mokhtar Hamham

In this paper, a compact reconfigurable tri-band/quad-band monopole antenna is presented. To achieve the multi-band behavior, two right-angled triangles were etched in a conventional rectangular patch, and a partial ground plane is used. Moreover, the proposed multi-band antenna is printed on a low cost FR4 epoxy with compact dimensions of 0.23[Formula: see text], where [Formula: see text] is calculated at the lowest resonance frequency. To provide frequency agility, a metal strip which acts as PIN diode was embedded in the frame of the modified patch. The tri-band/quad-band antenna performance in terms of reflection coefficient, radiation patterns, peak gain and efficiency was studied. The measured results are consistent with the simulated results for both cases. The simple structure and the compact size of the proposed antenna could make it a good candidate for multi-band wireless applications.


1992 ◽  
Vol 279 ◽  
Author(s):  
Yasuhiro Miyakawa ◽  
Jun Hashimoto ◽  
Naokatsu Ikegami ◽  
Jun Kanamori

ABSTRACTPrecise control of critical dimension(CD) loss (defined as the length of the top of contact hole minus the bottom of resist in this paper) and etched profile of contact holes is a key technology in the fabrication of Ultra Large Scaled Integrated Circuit(ULSI). In case of fine contact hole etching, small CD loss and vertical profile is essential. We have found out that N2 addition to Ar/CHF3/CF4 sharpens etched profile with CD loss kept small. And N2 addition also increases etch rate without a heavy deterioration of selectivity of SiO2 versus heavily doped n-type poly cry stall ine Si(n+ poly Si). Mechanisms of changes in etching characteristics have been investigated and discussed with the emphasis on adlayer formed on etched surface.


1995 ◽  
Vol 06 (01) ◽  
pp. 91-124
Author(s):  
INDER J. BAHL

Advanced military microwave systems are demanding increased integration, reliability, radiation hardness, compact size and lower cost when produced in large volume, whereas the microwave commercial market, including wireless communications, mandates low cost circuits. Monolithic Microwave Integrated Circuit (MMIC) technology provides an economically viable approach to meeting these needs. In this paper the design considerations for several types of MMICs and their performance status are presented. Multi-function integrated circuits that advance the MMIC technology are described, including integrated microwave/digital functions and a highly integrated transceiver at C-band.


1985 ◽  
Vol 28 (6) ◽  
pp. 24-26
Author(s):  
Michael Bustamante ◽  
Garrett Hicks

This paper describes the methods used by Chrysler Huntsville Automotive Electronics to obtain the quality, durability and reliability characteristics needed to fulfill the 193,200-km (120,000 mile) field performance requirements for Chrysler engine controls, radios and other electronic feature products. The paper will describe a case history, including the steps taken by both Chrysler Huntsville Automotive Electronics plant and one of their integrated circuit suppliers to attain certain quality levels.


2016 ◽  
Vol 9 (5) ◽  
pp. 1191-1196 ◽  
Author(s):  
Yogesh Kumar Choukiker ◽  
Jagadish Chandra Mudiganti

A compact size hybrid fractal antenna is proposed for the application in wideband frequency range. The proposed antenna structure is the combination of Koch curve and self-affine fractal geometries. The Koch curve and self-affine geometries are optimized to achieve a wide bandwidth. The feed circuit is a microstrip line with a matching section over a rectangular ground plane. The measured impedance matching fractal bandwidth (S11 ≤ −10 dB) is 72.37% from 1.6 to 3.4 GHz. An acceptable agreement is obtained from the simulated and measured antenna performance parameters.


2019 ◽  
Vol 8 (2) ◽  
pp. 596-603
Author(s):  
Nur Hamizah Muhamad Mokhtar ◽  
Norun Abdul Malek ◽  
Ahmad Zamani Jusoh ◽  
Khamis Ali ◽  
Farah Nadia Mohd Isa ◽  
...  

The interest for compact antennas in wireless communication increase due to the portability and mobility of the communication devices. Generally, an antenna at low frequency exhibits in large physical size. This project investigates the design of an antenna at 400 MHz. The simulation of the antenna has been performed using CST MWS. Since medical applications are dealing with low frequency, it will lead to large size of antenna which brings a challenge for wireless personal area network (WPAN). It is well known that the antenna performance decreases (according to Chu’s equation) as the size of antenna decreases. Therefore, antenna miniaturization using Meander Line (ML) will be taking place to overcome the challenges. Thus, this paper presents a comparison between i) printed dipole antenna without meander line technique, ii) printed dipole with meander line technique and iii) printed monopole antenna with meander line technique. The results show that an estimation of reduction size by 50% can be achieved using Meander Line technique.


Telecom ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 285-301
Author(s):  
Mariella Särestöniemi ◽  
Marko Sonkki ◽  
Sami Myllymäki ◽  
Carlos Pomalaza-Raez

This paper describes the development and evaluation of an on-body flexible antenna designed for an in-body application, as well as on-body communications at ISM and UWB frequency bands. The evaluation is performed via electromagnetic simulations using the Dassault Simulia CST Studio Suite. A planar tissue layer model, as well as a human voxel model from the human abdominal area, are used to study the antenna characteristics next to human tissues. Power flow analysis is presented to understand the power flow on the body surface as well as within the tissues. Simulation results show that this wearable flexible antenna is suitable for in-body communications in the intestinal area, e.g., for capsule endoscopy, in the industrial, scientific, and medical (ISM) band and at lower ultra-wideband (UWB). At higher frequencies, the antenna is suitable for on-body communications as well as in-body communications with lower propagation depth requirements. Additionally, an antenna prototype has been prepared and the antenna performance is verified with several on-body measurements. The measurement results show a good match with the simulation results. The novelty of the proposed antenna is a compact size and the flexible substrate material, which makes it feasible and practical for several different medical diagnosis and monitoring applications.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Enze Zhang ◽  
Jinghui Qiu

A four-port dual-band dual circularly polarized (CP) stack-up patch antenna is introduced for multiple-input-multiple-output (MIMO) RFID application. The proposed antenna adopts two FR 4 substrates and one Rogers Ro4350b substrates. Two pairs of isolated ports work at FCC UHF/MW-RFID bands (0.902–0.928 and 2.4–2.485 GHz) with port isolations of 20 dB and 25 dB, respectively. Four inverted-F radiating elements fed with a 90° phase-delay feeding network realize the CP radiation at the FCC UHF-RFID band (0.902–0.928 GHz). The corner-truncated square slot and patch are implemented to obtain CP modes at the MW-RFID band. The relative impedance bandwidths in the FCC UHF and MW band are 10.9% and 9.4%, respectively, with peak gains of 4.1 and 7.2 dBic. The antenna’s MIMO performance of envelope correlation coefficient (ECC) is lower than 0.01, and diversity gain (DG) is close to 10 dB. Thanks to the stack-up configuration, the dual-band RFID antenna realizes good antenna performance with a compact size of 0.6 × 0.6 × 0.07 λ3.


Author(s):  
J. Michael Bertsch ◽  
Stephen P. Gent

Abstract Recent advancements in wearable medical technologies have streamlined health monitoring with simple, non-invasive measurements. These devices, however, are rarely capable of monitoring all the necessary parameters for an accurate measure of health, such as blood pressure, and can cost the user hundreds to thousands of dollars. The objective of this project was to design an affordable, user-friendly, wearable device capable of monitoring multiple parameters: body temperature, blood pressure, heart rate, blood oxygen, and body positioning. By combining wearable sensors with Inter-Integrated Circuit (I2C) technology, the data from many sensors can be transmitted while maintaining a compact size for a wearable. In parallel with this device, a mobile application was designed as an interface to receive real-time comprehensive measurements. This device could be used to reduce monitor application time in emergency medical settings and monitor patients in rural communities who are often hours away from the nearest medical centers.


2018 ◽  
Vol 19 ◽  
pp. 01037
Author(s):  
Łukasz Knypiński ◽  
Krzysztof Kowalski ◽  
Lech Nowak

In the paper the way of adaptation of the penalty function method to the genetic algorithm is presented. In case of application of the external penalty function, the penalty term may exceed the value of the primary objective function. This means, that the value of the modified objective function is negative, while in genetic algorithm the adaptation must be of positive value, especially it in the selection procedure utilizes the roulette method. The sigmoidal transformation is applied to solve this problem. The computer software is developed in the Delphi environment. The proposed approach is applied to optimization of the electromagnetic linear actuator.


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