Antenna Test Research Articles

Compact and simple antenna inspection testing range for 5G smartphones

Abstract Over-the-air antenna performance evaluation in the millimeter-wave band often relies on compact antenna test range systems, which require large reflectors and a substantial measurement range volume. Such setups are impractical for rapid testing in space-constrained environments such as antenna fault diagnosis in smartphone manufacturing facilities. This paper presents a novel design methodology for highly compact antenna inspection testing range utilizing offset parabolic reflectors specifically designed for 5G smartphones. The proposed design system employs three small offset parabolic reflectors configured to account for beam tilting caused by smartphone back covers, eliminating the need to physically reposition the smartphone during testing. By directing electromagnetic fields toward a fixed receiver antenna from multiple angles corresponding to different antenna module positions, the system streamlines the test procedure, significantly reducing measurement time and measurement range volume. The proposed antenna inspection testing range provides a cost-effective and efficient solution for 5G antenna fault diagnosis in manufacturing facilities, ensuring rapid and reliable inspection while minimizing space requirements on the production line.

Realizing Orthogonal Modes in Compact Cavity‐Backed Dual‐Polarized Antenna Through Simple Feeding Structures for Millimeter‐Wave AiP Applications

AbstractThis paper presents a dual‐polarized cavity‐backed antenna designed for mm‐wave applications, featuring simple feeding structures with a high‐isolation for 60 GHz compact AiP applications. The dual‐polarization design relies on two separate feed ports that excite two orthogonal modes within the same resonant cavity, achieving very high port isolation of up to 40 dB over the entire band. We conducted a detail analysis of the antenna, including its working principles and parametric studies. For verification, we fabricated an antenna test kit using standard printed process on substrates and measured the kit from the back‐side of a GSG probing platform. The proposed antenna demonstrates a wide impedance bandwidth, stable radiation patterns, very low cross‐polarization levels, and a high radiation efficiency. The co‐located cavity‐backed design ensures the compactness and facilitates easy integration with ICs in a very small AiP module. These features make the proposed antenna highly suitable for 60 GHz AiP applications, such as high‐data‐rate wireless communication and mmW polarimetric radar systems.

Research on the development trends of vehicular OTA antenna testing technology

Research on the development trends of vehicular OTA antenna testing technology

Automated Gain Measurement System for Wide-Band Antenna Based on Instruments Remote Access Techniques: Direct SCPI Commands

A novel approach to wide-band antenna gain measurement is presented in this article, offering practical solutions to address the challenges posed by traditional measurement methods. The proposed system enhances efficiency, reduces complexity, and improves accuracy, making it a valuable tool for antenna testing in research and industry settings. A discussion of the challenges and complexities involved in measuring the specifications of manufactured antennas is made. We are particularly focusing on wide-band antenna gain measurement. It highlights the need for special equipment and expertise to conduct these tests effectively, especially for wide-band antennas. The proposed automated measurement system aims to simplify and streamline the gain measurement process by remotely driving the necessary instruments and reducing the complexity of the measurement mechanism. The novelty of this new automated measurement system can be divided into two branches. The first branch improves the standard approach of wide-band antenna gain measurement. The second branch modifies the structure of the software of the traditional remote access applications by mixing the operational instructions of the instrument with the direct SCPI commands. The resulting software has the ability to remotely drive many instruments synchronically, reducing the number of experienced people needed to complete the measurement process.

Instrumental test of patch antennas manufactured for C-Band applications

Instrumental test of patch antennas manufactured for C-Band applications

Pattern Correction From Nonideal Compact Antenna Test Range Measurement

Pattern Correction From Nonideal Compact Antenna Test Range Measurement

Design and implementation of high-rigidity and high-precision satellite antenna rotating unit

The satellite antenna rotating unit is an important component that drives the satellite antenna to rotate in orbit, mainly composed of a stepper motor, harmonic reducer, and rotating transformer. This type of rotating unit has the advantages of small size, lightweight, high-rated output torque, and long rotating life. The high-stiffness and high-precision satellite antenna rotation unit is based on the existing antenna rotation unit. Through comprehensive improvement design, the measured closed-loop control has a rotation accuracy of better than 0.005°, a torsional stiffness of better than 6.5 Nm/(Å), a rotation accuracy of 6 times higher than the existing antenna rotation unit, a torsional stiffness increase of 13 times, and a rated output torque increase of 2.4 times. The article introduces the development of components, measurement of torsional stiffness, and measurement of rotational accuracy for the high-stiffness and high-precision satellite antenna rotating unit. Finally, the development conclusion is given. The successful development of a high-stiffness and high-precision satellite-borne antenna rotation unit can not only meet the precise pointing control requirements of the mechanical movable antennas and terahertz antennas of the narrow beam with a width of 0.2° but also solve practical problems such as jitter in ground testing of data transmission or relay antennas and unstable pointing of point beam antennas in orbit.

Microstrip antenna with reflector and air gap for short range communication in 900 MHz band

This paper proposes a microstrip antenna that was made of a microstrip fed slot with a complimentary stub on a single dielectric medium. This antenna was integrated with a reflector and air gap for the application of short range communication (SRC) in a 900 MHz band. Analyses were made on the dimension of the reflector and the height of the air gap towards the antenna performance. Besides, an antenna field test was done for the propagation distance of the proposed antenna. As a result, with the antenna size of 13,770 mm2 , the measured return loss was -10.79 dB and the directivity gain was 7.44 dBi. Besides, with the effective isotropic radiated power (EIRP) of 7.44 dBm, it was predicted that at 100 m, the received signal would be around 60 to 70 dBm. Therefore, a high gain was produced by using a reflector with air gap and a compact size was achieved if compared to conventional high gain antenna designs such as Yagi Uda. Thus, it is suitable for a communication device such as the SRC application.

Forming Technology of a High-Frequency Conical Spiral Antenna

This paper introduces the integrated stereo forming technology of high-frequency conical spiral antenna, focusing on the material selection and processing of the supporting substrate, the surface metallization technology of the substrate, the establishment of spiral CNC machining models, and the control of CNC machining difficulties. The technology has been successfully applied in engineering, ensuring the continuity and consistency of three-dimensional microstrip in space. It also resolves the offset address problems of docking ends and ports asymmetry caused by microstrip splicing technology. The advantages of this technology include high processing accuracy, good consistency, high stability, and short processing cycle. The high-frequency conical spiral antenna produced has been verified by antenna testing, adaptability tests of mechanical environment and temperature environment, and its performance is stable, which can meet the requirement of the design and application. It has been successfully applied to electronic countermeasures equipment. The test results indicate that the high-frequency conical spiral antenna has good electrical performance and consistency. So the integrated stereo forming technology for high-frequency conical spiral antenna is feasible and reliable. This provides a useful reference for the research on the similar products processability.

Polarization Agile Reconfigurable Rectangular Patch Antenna for Biomedical Applications

A polarization agile patch antenna resonating at 2.4 GHz ISM band is presented. The antenna is based on a rectangular radiating element along with reconfigurable parasitic patches located at its periphery of the radiating element. Two switching diodes are used to reconfigure the geometry of the radiating element. Upon proper biasing of the switching diodes the antenna attains linear or circular (LHCP/RHCP) polarization states. The entire antenna is modelled using a high-frequency structure simulator and is validated using an Agilent network analyser (N9925A) and antenna test systems for measuring impedance and radiation characteristics. Over the entire operating band, the antenna shows better impedance matching and achieves −10 dB impedance bandwidth of 100 MHz (2.40-2.5 GHz) in linear state and 85 MHz (2.41-2.495 GHz) in the circularly polarization states along with peak gain of 5.61 dBi for LP state and 4.98 dBi for CP state in the operatingrange.

ADVANCED ULTRAWIDEBAND PATCH ANTENNA FOR WEARABLE AND WBAN APPLICATIONS

Present communication devices are adopting an application-centric approach with the integration of electronic gadgets into wearable accessories in recent years. This paper presents a wearable antenna with a flexible textile substrate. The design comprises a low-profile, textile-based UWB (3.1-10.6 GHz) antenna of 25 × 20 × 1 mm<sup>3</sup> size with a defected ground structure. Design antenna performance characteristics have been simulated in Computer Simulation Technology studio. It offers a gain of 4.204 dBi at 5.11 GHz frequency and 2.993 dBi at 7.39 GHz frequency using a cotton substrate with a 1.6 dielectric constant. A simulated testing of the design antenna on a human body phantom has resulted in a gain of 0.697 dBi with a return loss of -30.863dB and 1.058 VSWR at 5.3125 GHz frequency. A specific absorption rate value of 1.64 W/kg of the designed antenna for 10 g tissue shows that it is safe for the human body. The patch antenna of the paper is promising for wearable, medical imaging, tumor detection, and other wireless body area network (WBAN) biomedical applications.

An Accurate Analytical Method to Determine the Range of Quiet Zone in Compact Antenna Test Range

An Accurate Analytical Method to Determine the Range of Quiet Zone in Compact Antenna Test Range

Resistance frequency selection surface framed reflector antenna for 5G OTA measurement

AbstractIndirect far field (IFF) over‐the‐air (OTA) test could be one of the most applicable test methods for 5G mmWave devices. The compact antenna test range (CATR) method has been introduced to the OTA test by 3GPP. Conventional metallic parabolic reflectors without edge treatment can lead to serious edge diffraction which results in high noise and low accuracy. The serrated reflector improves edge diffraction but performs poorly at low frequencies. Reflector antenna with a resistance frequency selection surface (RFSS) frame is proposed for 5G OTA CATR measurement at millimeter frequency, which collimates spherical incident waves into quasi‐plane waves in a relatively short distance, thus forming a quiet zone (QZ) in which large devices under test can be measured in small chamber. In this paper, the reflector with RFSS is investigated through the numerical and experimental methods, it is found that serrated RFSS frame with low edge diffraction could achieve the excellent QZ, which could be helpful in miniaturing CATR chambers for 5G OTA measurement.

Quadband Petal Reflector Antenna for Ground Communications: Combining four frequency bands into one innovative and reliable design

Future protected communications require soldiers on the ground to carry several antennas integrated with their manpacks to provide secure and reliable communications at a number of frequency bands. This article describes a novel quadband petal reflector antenna (QPRA) that combines four frequency bands into one using a quadruplexer. A dual-reflector antenna utilizing an axially displaced ellipsoid subreflector being fed with a quad-ridged horn provides communications at Ku-band transmit (Ku-Tx), Ku-band receive (Ku-Rx), K-band receive (K-Rx), and Ka-band transmit (Ka-Tx) frequencies simultaneously. The main reflector is made of six identical petals that can be quickly assembled and disassembled in the battlefield. The antenna is mounted on a lightweight gimbal to provide beam scanning over a hemispherical coverage. The antenna is mounted on a tripod structure for field operations and uses commercial off the shelf (COTS) components and 3D manufactured parts to minimize cost and mass. The novelty of the antenna presented in this article includes a wide bandwidth capability of 73%, the use of a petal reflector, a 3D manufactured quad-ridged horn, a high-performance quadruplexer, and the use of COTS gimbals for beam scanning. Antenna design, analyses, hardware, and test results are presented in this article. The measured results of the antenna agree well with the computed results validating the QPRA design.

A Survey of the Thermal Analysis of Implanted Antennas for Wireless Biomedical Devices.

Wireless implantable biomedical devices (IBDs) are emerging technologies used to enhance patient treatment and monitoring. The performance of wireless IBDs mainly relies on their antennas. Concerns have emerged regarding the potential of wireless IBDs to unintentionally cause tissue heating, leading to potential harm to surrounding tissue. The previous literature examined temperature estimations and specific absorption rates (SAR) related to IBDs, mainly within the context of thermal therapy applications. Often, these studies consider system parameters such as frequency, input power, and treatment duration without isolating their individual impacts. This paper provides an extensive literature review, focusing on key antenna design parameters affecting heat distribution in IBDs. These parameters encompass antenna design, treatment settings, testing conditions, and thermal modeling. The research highlights that input power has the most significant impact on localized temperature, with operating frequency ranked as the second most influential factor. While emphasizing the importance of understanding tissue heating and optimizing antennas for improved power transfer, these studies also illuminate existing knowledge gaps. Excessive tissue heat can lead to harmful effects such as vaporization, carbonization, and irreversible tissue changes. To ensure patient safety and reduce expenses linked to clinical trials, employing simulation-driven approaches for IBD antenna design and optimization is essential.

Methods of control and measurements of components of the onboard radio engineering complex

Background. The relevance of the topic of this work is due to the need to increase the reliability and quality of the results of measuring control of modules of various levels and antenna arrays that are part of the onboard radio engineering complex, as well as to increase the reliability and parametric efficiency of the radio engineering complex. Aim. Development of a method and methodology for integrated control of radio frequency modules of the 1st, 2nd, and 3rd levels in the process of design, production and testing based on modern automation tools and processes. Methods. Full-scale experiment, computer modeling, programming, expert assessments, research, autonomous and acceptance tests were used. Results. The choice of a working control model was made. Based on it, an automated workplace has been developed. It includes integrated control and measuring equipment controlled by special software, a software package with a common operator interface. To control the testing process, a software package has been developed that automatically sets the necessary operating modes of the modules and provides a stimulating signal from the vector network analyzer in accordance with the specified parameters. After the end of testing, a test report is generated and printed. If the modules are tested for compliance with technical specifications, the protocol is formed in accordance with GOST. The test sequence is developed using the NI TestStand automated testing environment, and the routines that control the operating modes of the products are developed using C/C++ and NI LabVIEW graphical development tools. The automated workplace implements the following functions: functional electronic control of circuits and nodes of radio frequency modules and the product as a whole, electrical integrity control of circuits and nodes of frequency modules, programming of digital components, conducting complex tests of frequency modules, conducting complex tests of antennas and antenna arrays. The developed algorithm includes a stage of self-testing of the automated workplace hardware. After entering the necessary information, a step-by-step cycle of monitoring the module parameters is started. It begins with the connection of the device under test to the automated workplace and ends with the preparation of a test report and a message about the validity or unfitness of the totality of the measured parameter values. The final conclusion about the operability of the control object is made automatically after the measurement of all parameters is completed in the form of a pop-up dialog box. It contains one of two mutually exclusive statements: «Control successfully passed», «Control failed». Conclusion. The algorithm and methodology of automated control and tuning have been developed, which allows to increase the reliability and accuracy (by 5–15 %) of the measurement results of the electrical parameters of the PPM at the stages of tuning and testing. A software package for automated control has been developed. An automated control workplace has been developed.

Design and Construction of 2.4 Ghz Omnidirectional Antenna as Wireless LAN Transmitter (Case Study at Bukit Indah Campus, Malikussaleh University)

Communication with a wireless system is one of the mainstay communications so that communication integration is achieved. For this reason, Malikussaleh University provides a wifi network on each campus, one of which is the Bukit Indah campus. So that the achievement of wifi access points on mobile devices needs to be improved so that it is achieved properly. Therefore it is necessary to optimize the placement of access points on the Malikussaleh University wifi network. Modeling an omnidirectional antenna that has a range of 360 ° is one solution. The method applied is to design and build an omnidirectional antenna on the Bukit Indah Campus of Malikussaleh University. Based on simulations on Mobile Radio, the largest network pathloss is 116.2 dB and the smallest is 102.0 dB. The results of omidirectional antenna testing conducted 5 times obtained the largest download speed worth 3.18 Mbps with 314ms ping at a distance of 30 meters and the smallest download speed worth 0.55Mbps with 195ms ping at a distance of 150 meters. The farther the distance of the antenna the lower the ping and packet loss, from the test results obtained an average ping of 267.8ms and the largest packet loss percentage of 0.4%. The ideal distance for this antenna is 30 to 110 meters and can even get a longer distance provided there are no obstacles. With this distance it is ideal for an assembled antenna with makeshift materials that we often encounter in everyday life.

A Comprehensive Review of In-Body Biomedical Antennas: Design, Challenges and Applications.

In-body biomedical devices (IBBDs) are receiving significant attention in the discovery of solutions to complex medical conditions. Biomedical devices, which can be ingested, injected or implanted in the human body, have made it viable to screen the physiological signs of a patient wirelessly, without regular hospital appointments and routine check-ups, where the antenna is a mandatory element for transferring bio-data from the IBBDs to the external world. However, the design of an in-body antenna is challenging due to the dispersion of the dielectric constant of the tissues and unpredictability of the organ structures of the human body, which can absorb most of the antenna radiation. Therefore, various factors must be considered for an in-body antenna, such as miniaturization, link budget, patient safety, biocompatibility, low power consumption and the ability to work effectively within acceptable medical frequency bands. This paper presents a comprehensive overview of the major facets associated with the design and challenges of in-body antennas. The review comprises surveying the design specifications and implementation methodology, simulation software and testing of in-body biomedical antennas. This work aims to summarize the recent in-body antenna innovations for biomedical applications and indicates the key research challenges.

Electroceramic based on Ca3-xBaxZrSi2O9 solid solutions for microwave and radiofrequency application

The structural and dielectric characterization of the Ca3ZrSi2O9 (CZS) ceramic compound and the Ca3-xBaxZrSi2O9 (BaCZS) solid solution were investigated for their application in radiofrequency (RF) and microwave (MW) antenna devices. All of the samples were synthesized using the solid-state route. The structural characterization of the samples was performed by X-ray powder diffraction pattern. Infrared and Raman spectroscopy were used to correlate the absorption bands of the main chemical bonds in the materials. Scanning electron microscopy was used to examine the surface and microstructure of the samples. Dielectric properties at MW and RF ranges were analyzed using the Hakki-Coleman and Silva-Fernandes-Sombra methods. The CZS electrocemaric showed a dielectric relative permittivity (ε’) of 10.96, a dielectric loss (tan δ) of 8.28 × 10−4 at 10.20 GHz, and a resonant frequency temperature coefficient (τf) of −44.30 ppm °C−1. The influence of Ba ions on the CZS phase was evaluated using molar ratio variations (x = 0.15, 0.30, and 0.45), denotated as Ca2.85Ba0.15ZrSi2O9, (0.15BaCZS), Ca2.70Ba0.30ZrSi2O9, (0.30BaCZS), and Ca2.55Ba0.45ZrSi2O9 (0.45BaCZS), respectively. Among these samples, 0.45BaCZS showed a τƒ of approximately zero (−5.78 ppm °C−1), demonstrating an improvement in the material with the addition of Ba. Preliminary tests at MW and RF showed that the permittivity values and dielectric losses varied accordingly with the increase in the proportion of barium, as well as τƒ. For the dielectric resonator antenna (DRA) tests, the samples operated below −10 dB, between 6.57 and 7.7 GHz, behaving like materials used in microwaves devices for C-Band applications.

Design and analyses of shipborne multifunctional Automatic Identification System (AIS) antenna

ABSTRACT This paper is introducing analyses of new design of the automatic identification system (AIS) ships antenna that will serve for both VHF-band radio and satellite tracking and identification system for maritime applications. The current AIS network is an automatic tracking system used by ships of vessel traffic service for identification and location of vessels by electronically exchanging data between nearby ships and on-shore base station. In the AIS system for the electronic data exchange, the very high frequency (VHF) range is used. Utilizing of the VHF range makes the AIS as short-range communication, identification and collision avoidance system between AIS equipped ships and base station is possible in the antennas line-of-sight . In order to widen the range of the AIS from short range up to long or global range, AIS communication should be used via a satellite. In order to provide communication via satellite as well should be designed multifunctional antenna for both radio AIS (R-AIS) and satellite AIS (S-AIS) communication antenna. The analyses and design of a new multifunctional antenna, calculation and development, including implementation and testing of helical VHF antenna for R-AIS and S-AIS equipment are discussed.