Contactless Testing Research Articles

Hybrid data-driven and mechanism-modeling approaches for online injection rate sensing of dual-fuel co-direct injector under carbon neutral background

This study proposes an innovative concept for online sensing of the injection process. By using the injector inlet as the pressure signal detection point, contactless testing of the injector is achieved, theoretically requiring no structural changes to commercial engines or standard injectors. For the pilot diesel injection, the pressure signal is abstracted as the evolution and transmission of Riemann waves, and the relationship between pressure and mass flow rate is established. Additionally, correction and decoupling methods for system interference and superimposed waves are proposed to extract Riemann single-wave components caused by injection. For the main fuel gas injection process, a data-driven injection mass neural network prediction model is constructed based on the pressure drop characteristic, which achieves quantitative sensing of the injection characteristics. Moreover, concerning gas pressure fluctuation, the interference phenomenon in the first-order differential pressure signal is identified. It is found that gas pressure waves propagate as second-order micro-pressure in the HPDI system, and the columns of pressure waves do not interfere with each other. A qualitative reconstruction method for the injection rate curve is developed based on 1D mechanistic models. In conclusion, this study uses hybrid data-driven and mechanism-modeling approaches to achieve online sensing. By comparing with offline testing methods, it exhibits high accuracy, with errors in the majority of injection parameters remaining within 5.5%.

Testing of chlorine dosage in drinking water using microstrip patch sensor

A new method using microstrip patch sensor is designed, simulated, and measured to detect the dosage of added chlorine to the drinking water using the relation between permittivity and matching impedance. The simulation is done using computer simulation technology-microwave studio software. The proposed sensor is designed on a single FR-4 layer with a low profile, 0.499 GHz bandwidth, center frequency of 2.94 GHz, gain of 6.55 dBi, and a good front to back ratio of 17.84 dB. In this work, the antenna design is started from a conventional patch antenna equation. Then, an optimization process is performed to achieve good parameter values for obtaining the desired objective. The objective is to utilize the microwave frequency to measure the chlorine dosage in water. The measurement results proved that the matching impedance can be used to find out the dosage of chlorine in drinkable water. The proposed method overcomes the open-ended coaxial probe method in terms of experimental time and contactless testing and shows high matching with the latter actual data. Moreover, the proposed method overcomes the conventional methods in terms of continuity and large scale of testing, non-contacting with the samples of water, and no additive chemical materials, which make the water samples not drinkable.

Modelling and analysis of contactless sensor for TSV fault based on resonant inductive coupling

In order to solve the problems of inefficient detection, high cost, and high damage rate of existing Through Silicon Via (TSV) contact detection, contactless testing techniques are urgently needed to eliminate the many problems associated with contact. In this paper, a contactless antenna utilizing resonant inductive coupling is presented. This coupling method, as compared to the conventional capacitive coupling technique allows faults detect from longer distances. The results of 3D full wave simulations in the High Frequency Structure Simulator (HFSS) and Advanced Design System (ADS) show that various faults, such as voids and pinholes, can be detected when the distance between the TSV and the antenna remains about 10 μm. Defective TSVs cause changes in the operating current and voltage pulses at the detection antenna. Simultaneously, changes in the field distribution around the TSVs are used to explain the changes in current and voltage pulses. Furthermore, the effects of antenna parallel movement were also investigated.

Two approaches for the passive charge management of contactless test masses

Free floating test masses (TM) of inertial reference instruments accumulate charge mainly through the triboelectric effect during separation from their housings and, if in the space environment, from cosmic radiation. These charges will degrade the accuracy of high sensitivity accelerometers and drag-free sensors. We demonstrate in ground testing two passive bipolar charge management systems using photoelectrons emitted from gold coated surfaces under illumination by ultraviolet light emitting diodes (UV-LEDs) with 255 nm, 275 nm, and 295 nm central wavelengths. The first method uses fast photoelectrons, generated by two 255 nm UV-LEDs with adjustable-intensity (through fine-tuning of their excitation currents) and illuminating the TM and its housing respectively. A second technique uses slow photoelectrons generated by one UV-LED, of either 275 nm or 295 nm, directed at the TM. Fast and slow electrons are defined as having kinetic energies after photoemission above and below , where is the maximum allowable potential required for normal operation of the TM. In its optimized configurations and following an exposure of <30 s to UV, the fast-photoelectron control system converges to zero TM potential from ±1 V with a drift of ≈1.5 mV/day. The slow-photoelectron system requires about 5 min to converge to zero TM potential from 100 mV, with a similar drift of ≈2.0 mV/day. For reference, for the LISA and LISA pathfinder sensors. Insight into the slow photoelectrons charge control method is provided by our simple Gaussian model of the work function for gold films (that approximates their quasi-triangular measured shape): 4.6 eV center, 0.2 eV standard deviation, and 4.30 eV and 4.90 eV cutoffs. The longest wavelength (lowest energy) photoemission is obtained with the 295 nm LED (11 nm FWHM) at about 285 nm (4.35 eV), where only about 3.5% of the photons have an energy above the photoelectric threshold. While the two-source UV fast photoelectron method is a modification of the LISA Pathfinder approach, the slow photoelectron method is a new passive charge management technique. These two passive techniques were developed for instruments without sensing and activation systems. For instruments with electric fields surrounding the TM and more complex geometries additional adaptations are required.

Safety challenges experienced by driver license examiners and related safety measures

Driver license examiners serve as the “gatekeepers” to the world of driving. These examiners administer driving tests and issue driver licenses to prospective drivers that demonstrate driving competency. Unfortunately, this community of workers is vulnerable to experiencing safety incidents as they test prospective drivers with limited driving proficiency. Understanding the safety challenges these workers experience professionally is fundamental to identifying and adopting relevant safety measures. Towards achieving this goal, interviews were conducted with driver license examiners in North Carolina to compile the safety challenges they professionally experience. Additionally, safety management measures that they adopt regularly and others that they recommend for possible future adoption were gathered. The reported safety challenges include prospective drivers reporting for testing and retesting without sufficient training, the existence of communication and language barriers, prospective drivers adopting driving customs learned in other countries, and experiences of entering unclean vehicles. Safety measures that the driver license examiners adopt regularly include the use of widely adopted terms and hand gestures to overcome communication challenges, being prepared to take control over the vehicle steering, encouraging prospective drivers to hold the learner’s permit and gain additional experience, and others. Suggested safety measures for possible future adoption include empowering examiners to terminate the test when appropriate, enforcing a limited wait time following the issuance of a learner’s permit prior to attempting the driving test, and the regular adoption of contactless testing methods popularized during the COVID-19 pandemic. The study findings can be leveraged to enhance the safety of driver license examiners.

Use Of A Disposable At-Home System To Support Contactless Sleep Apnea Testing & Therapy Initiation In A HF Clinic During The Covid-19 Pandemic

Background: The COVID pandemic presented many challenges to providing care to our HF patients. One of our challenges was the closure of our sleep lab for sleep apnea testing and CPAP titration. We also encountered patient reluctance to perform sleep testing with re-usable home equipment. In attempt to address these issues, we employed the WatchPATTM ONE device (Itamar Medical) - a disposable Bluetooth-enabled technology that uses peripheral arterial tonometry - to assess patients for sleep-disordered breathing (SDB) without an in-person visit or a facemask. At-home CPAP initiation and auto-titration was performed in appropriate patients to create a fully contactless testing and treatment program.Methods: From March 2020 - March 2021 patients with suspected SDB during a virtual HF Clinic visit were referred for home sleep testing using the WatchPATTM ONE device. Suspicion for SDB breathing was based on meeting at least 1 of 5 screening criteria used in our HF Clinic and a STOP-BANG score > 3. After insurance approval, a device was mailed to the patient for overnight testing. Results were uploaded into the CloudPAT platform and read by our Center's sleep cardiologist. Patients without complex SDB, underwent remote device fitting via an online DME company followed by CPAP auto-titration. Time to therapy and compliance with CPAP was assessed using the cloud-based system.Cone Health SDB Screening CriteriaPoorly-controlled HTNRecurrent/refractory AFFrequent PVCsFatigue out of proportion to HF severityBMI > 35Results:Patients tested111Positive for SDB (AHI ≥ 5)81 (73%)Patients with significant central SA (cAHI > 5)20%Patients with successful remote CPAP initiation24 (30%)Mean time from virtual visit to therapy53dConclusions:• Sleep apnea is a common comorbidity in HF patients • The WatchPATTM ONE system was an effective way to continue to test our HF patients for SDB in a virtual setting with a disease prevalence similar to standard in-lab testing and had the ability to discern between obstructive and central sleep apnea • In our initial virtual sleep apnea program, nearly 1/3 of patients with SDB went onto CPAP treatment via a remote DME Turnkey service with a favorable time to treatment and a completely contactless workflow

Contactless testing of insulation damages distribution of the underground pipelines

The results of practical inspections of the underground pipelines insulation damages distribution and the use of the method of non-contact current measurements are presented. Based on the mathematical model of magnetic field of the underground pipeline (taking into account the leakage of current into the environment), it is possible to distinguish local insulation damages, which is located at a distance greater than the depth of the pipeline.

Diotic and Antiphasic Digits-in-noise Testing as a Hearing Screening and Triage Tool to Classify Type of Hearing Loss.

The digits-in-noise test (DIN) is a popular self-test measure that has traditionally been used to screen for hearing loss by providing either a pass or refer result. Standard approaches either tested each ear monaurally or used a binaural diotic version where identical digits and noise were presented simultaneously to both ears. Recently, a dichotic, antiphasic version was developed, increasing sensitivity of the DIN to unilateral or asymmetric sensorineural hearing loss (SNHL) and conductive hearing loss (CHL). The purpose of this study was to determine predictors and normative ranges of the antiphasic and diotic DIN and to determine if a combination of diotic and antiphasic DIN could accurately categorize hearing into (1) normal, (2) bilateral SNHL, or (3) unilateral SNHL or CHL. The analytical sample consisted of 489 participants between the ages of 18 and 92 years with varying types, symmetry, and degrees of hearing loss. Degree and type of hearing loss were determined based on standard clinical four-frequency (0.5-4 kHz) pure-tone air and bone conduction threshold averages. The sample consisted of bilateral normal hearing (n = 293), bilateral SNHL (n = 172), unilateral SNHL (n = 42), and CHL (n = 32). All participants (n = 489) first completed an antiphasic DIN (digit stimuli 180° out-of-phase between ears), while 393 of the sample also completed a diotic DIN. Two procedures were assessed for their ability to categorize hearing into one of the three hearing groups. The first used a fixed antiphasic cutoff combined with a cutoff formed by a linear combination of antiphasic and diotic speech recognition threshold (SRT) or binaural intelligibility-level difference. Poorer ear pure-tone average was the strongest predictor of antiphasic DIN score, whereas better ear pure-tone average explained more of the variance in diotic SRT. The antiphasic DIN sensitivity and specificity was 90% and 84%, respectively, for detecting hearing loss, with outstanding area under the receiver operating characteristics values exceeding 0.93 to identify hearing loss in the poorer ear. The first fixed SRT cutoff procedure could categorize 75% of all participants correctly, while the second procedure increased correct categorization to 79%. False negative rates for both procedures were below 10%. A sequential antiphasic and diotic DIN could categorize hearing to a reasonable degree into three groups of (1) normal hearing; (2) bilateral SNHL; and (3) unilateral asymmetric SNHL or CHL. This type of approach could optimize care pathways using remote and contactless testing, by identifying unilateral SNHL and CHL as cases requiring medical referral. In contrast, bilateral SNHL cases could be referred directly to an audiologist, or nontraditional models like OTC hearing aids.

ПІДВИЩЕННЯ ЕФЕКТИВНОСТІ ДІАГНОСТИКИ ШИХТОВАНИХ ОСЕРДЬ ТА ВИЗНАЧЕННЯ ПОТОЧНОГО СТАНУ СИНХРОННИХ ДВИГУНІВ

Topicality. Today a large number of synchronous motors with long mean-time-between-failures operate under the conditions of industrial enterprises. They are mainly characterized by difference from the published electromagnetic parameters and degraded energy and reliability indicators, increased heating of the windings and electromagnetic vibrations, which causes a reduction in power on the shaft. Among other reasons, this is due to changes in the properties of laminated stator cores, which is the main structural element that is not replaced during repairs. Purpose. Determination of the main set of independent diagnostic parameters that would reliably distinguish the main types of defects of stator cores, first of all loosening and shorting, during their local testing using induction method and features of artificial neural networks in problems of video identification of core surface and determination of the state of synchronous motors. Metodology. The research methods of theoretical calculations of nonlinear electric circuits with non-sinusoidal power supply and methods of video identification for determination of diagnostic parameters and defects of laminated cores and the theory of neural networks in determining the current state of cores and synchronous motors in general were used during the research. Results. The obtained results specify the conditions of local testing of laminated cores from the standpoint of determining the required set of diagnostic parameters sensitive to the main types of defects, using a contactless test method, reveal the features of the use of neural network analyzers to determine the defects of the tooth zone by video identification and substantiate the principles of application of artificial neural networks in problems of predicting the states of major structural units and synchronous motors in general, due to changing properties of stator cores. Originality. The obtained results allow determining the state of the stator core and taking into account the influence of its change on the current state of synchronous motors with long or intensive operation. Practical value. The research results make it possible to assess the changes in the main parameters and characteristics of synchronous motors, determined by the actual state of the laminated stator cores and take into account their impact on energy efficiency, reliability and other operating parameters of synchronous motors. References 10, figures 7.

Autonomous Scan Patterns for Laser Voltage Imaging

The semiconductor industry ramping up design capabilities for emerging technologies is facing new test quality and yield management challenges. To facilitate debugging of the first silicon, diagnosis of yield issues, and to enable repair processes, an accurate defect isolation is needed with support of advanced test, diagnostic, and yield analysis tools. Laser voltage imaging (LVI), laser voltage probing (LVP), and electron-beam testing are popular diagnostic techniques for scan chain failures. As scan remains instrumental in developing more advanced DFT technologies, its reliable operations are essential for test pattern bring-up, failure analysis, and yield learning. Running LVI tests at early stages of a design process involves a sophisticated infrastructure to offer a nanometer diagnostic resolution with a non-destructive failure isolation. However, as the use of external testers may not be feasible besides providing power and clock signals, the paper demonstrates how to reuse on-chip EDT compression environment to generate and apply LVI-aware scan patterns for advanced contactless test procedures. The presented approach avoids the repetitive loading of scan chains, requires no seed patterns to encode LVI tests, has virtually no area overhead, and offers a flexible selection of non-toggling scan chains in a low power test mode. Furthermore, there are no constraints or requirements imposed by designs that could limit the applicability of the scheme. The proposed solution does not compromise the test compression performance, marked by test data reduction ratios, test coverage, and test time. Hence, there are no modifications needed in existing flows and tools to implement the method besides the use of recommended polynomials.

TSV fault contactless testing method based on group delay

ABSTRACT As through silicon via (TSV) in three-dimensional (3-D) stacked integrated circuit (IC) has become micro-nanosized, the conventional wafer probe technology cannot fulfil the current detection requirements, so new testing techniques are urgently needed. In this paper, we present amethod for TSV contactless testing based on group delay. The group delay-based mixed testing stimulus is applied to the pending testing TSV through acontactless probe, and then output response is obtained by adetector. The crest factor (CF) is measured and calculated, and fault diagnosis is performed according to the CF difference between faultless and faulty TSV. The void fault of the signal-ground-TSV (SG-TSV) is also detected by the contactless testing method, and its fault function is obtained. The result shows that aresistive open circuit fault as small as several ohms can be detected through this approach. Finally, the fault testing resolution is improved by adjusting the modulation mode of the multi-tone signal.

Robot deployed Laser-Ultrasonic NDT system for inspection of large aircraft structures

The mandatory Non-Destructive Testing (NDT) by the aerospace industry for both present and future generation hybrid aircraft using thick composite structures poses many challenges for traditional inspection techniques. Laser Ultrasonic Testing (LUT) deployed by a robot for inspection of modern aerospace composite components shows good promise. It is a non-contact method offering the possibility of fast scan times without the need for couplant. This paper presents the latest work-in-progress for the design and development of the system developed by the ACCURATe consortium. ACCURATe is an ongoing H2020 Clean Sky 2 part funded project to develop a laser ultrasound based NDT system prototype for fast and contactless testing of large carbon fibre reinforced polymer (CFRP) aircraft structures.The approach is based on a non-contact laser generated and detected pulsed ultrasound technique with delivery of both the laser ultrasound excitation and detection pulses through flexible optical fibres. The backscattered light from the lasers is also collected into a fibre. The measurement head, which contains the two beam outputs and the light collection optics is raster scanned over the surface by a 6-axis robot arm. A balanced two wave mixing interferometer (B-TWM) is used for the demodulation of the ultrasonic waves.The system has recently been used to scan a reference panel, and a scrap panel of fuselage, the latest test results are presented and show promising progress against the project objectives.

An In Vitro Evaluation of the Biocidal Effect of Oregano and Cloves’ Volatile Compounds against Microorganisms Colonizing an Oil Painting—A Pioneer Study

In this study, the biocidal activity of two plant derivatives (oregano and cloves’ essential oils—EOs) was evaluated, as a potential innovative and eco-friendly cleaning method for canvas paintings. The object of the study was the oil painting on canvas entitled “Studio di nudo” (Giovanni Maria Mossa, 1921), showing stains caused by microorganisms. The research focused on: (1) isolation and identification of microorganisms associated with discolorations on the obverse and reverse sides of the canvas; (2) evaluation of biocidal activity of selected EOs against fungal and bacterial collections. The phylogenetic identification was conducted with both cultivation and molecular methods. The canvas was mainly colonized by Penicillium, Aspergillus, and Cephaloteca fungal genera and by bacteria of the Bacillus genus. To evaluate the biocidal effect of the EOs’ volatile components only, an antibiogram assay (agar disc diffusion method) and a customized assay (named the contactless test) were conducted. Tested EOs showed antimicrobial activity on fungi and bacteria. However, compared to cloves, oregano EO exhibited a better inhibition activity both in contact and contactless tests. The work is pioneering for the use of EOs’ volatile compounds against oil painting biodeteriogens, and gives insights into possible extended, innovative and eco-friendly cleaning methods for painting control procedures.

Cluster Analysis of IR Thermography Data for Differentiating Glass Types in Historical Leaded-Glass Windows

Infrared thermography is a fast, non-destructive and contactless testing technique which is increasingly used in heritage science. The aim of this study was to assess the ability of infrared thermography, in combination with a data clustering approach, to differentiate between the different types of historical glass that were included in a colorless leaded-glass windows during previous restoration interventions. Inspection of the thermograms and the application of two data mining techniques on the thermal data, i.e., k-means clustering and hierarchical clustering, allowed identifying different groups of window panes that show a different thermal behavior. Both clustering approaches arrive at similar groupings of the glass with a clear separation of three types. However, the lead cames that hold the glass panes appear to have a substantial impact on the thermal behavior of the surrounding glass, thus preventing classification of the smallest glass panes. For the larger panes, this was not a critical issue as the center of the glass remained unaffected. Subtle visual color differences between panes, implying a variation in coloring metal ions, was not always distinguished by IRT. Nevertheless, data clustering assisted infrared thermography shows potential as an efficient and swift method for documenting the material intervention history of leaded-glass windows during or in preparation of conservation treatments.

Induction brazing of cermets to steel and eddy current testing of joint quality

The principal aim of the study was to demonstrate the feasibility of induction brazing of TiC-based cermets with Fe- and Ni-alloy binders under ambient atmosphere. A secondary aim was to investigate the possibility of using an innovative rapid non-destructive contactless testing method based on eddy current measurement for the evaluation of joint quality. Ag- and Cu-based filler metals and suitable fluxes developed for brazing of cemented carbides (WC-Co) to steels were employed. Results of the microstructure study and testing of shear strength enabled us to conclude that TiC-based cermets (TiC-FeCr and TiC-NiMo) can be successfully brazed under ambient atmosphere using filler metals and fluxes developed for WC-based cemented carbides. The shear strength of joints over 200 MPa can be achieved. Under similar brazing conditions, TiC-FeCr/steel joints compare favourably with TiC-NiMo/steel joints in terms of shear strength. The shear strength of TiC cermet/steel joints brazed with silver-based filler metal (Ag449) slightly increases (~13%) after prolonged heating at elevated temperature (250 °C). It was found that eddy current testing is prospective for rapid assessment of brazed joints quality with identical dimensions and chemical composition of multilayer structures. The differentiation of measurement results is the best at frequencies in the range of 10 … 100 kHz.

A Compact High-Resolution Resonance-Based Capacitive Sensor for Defects Detection on PCBAs

Increased density of printed circuit board assembles (PCBAs) is diminishing physical contact test access of the in-circuit testing (ICT) solutions for defects detection. As a result, it is necessary to design contactless test solutions with high spatial resolution to overcome the current test limitations. In this paper, a compact contactless sensor is presented for monitoring the fabrication quality of PCBAs. The sensor consists of an inductor-capacitor-(LC)-based resonant circuit and it can detect defects on metallic traces of PCBAs in close proximity without a contact. The sensor is designed such that, strong electric field is confined around the sensor tip, which creates strong capacitive coupling between the sensor tip and devices under test (DUTs) within a small region for sensing, i.e. high resolution sensing. The sensitivity of the proposed sensor is verified by the simulated and experimental 2D surface mapping results with sample DUTs, and it shows that the sensor can detect the open or short defects with a size as small as 0.15 mm × 0.2 mm. Circuit models are proposed to predict the sensing behavior and for guiding the design. The proposed sensor shows great potential to be used in the real-time monitoring of defects along the manufacturing supply chain.

ANALYSIS OF SURFACE MICROGEOMETRY AND STRUCTURE OF LAYERED BIOMATERIALS USED FOR PROSTHETIC CONSTRUCTIONS IN DIGITAL TECHNOLOGIES

Veneering layers of prosthetic substructures are responsible for tribological cooperation with opposite teeth in the stomatognathic system (SS). Investigations of microgeometry and structure of veneering layers are aimed at checking to what extent these layers replicate enamel parameters, which, under complex load conditions, are characterized by the phenomenon of resistance to tribological wear. Ceramic veneering layers are dedicated for substructures made in digital technologies from factory fittings by milling and laser sintering of metal powders. Using a confocal microscope, contactless tests of the surface layer stereometry were performed and surface roughness parameters were determined on samples of ceramics veneering of prosthetic substructures. The analysis was performed in comparison to the natural enamel of premolars and molars. The shaping of the surface of materials veneering the substructures is similar to the regularity determined in the statistical analysis of the enamel roughness. Layers facing samples from milling technology are characterized by lower values of roughness parameters than layers created on substructures made of SLM technology.

A 3D fluid-solid interaction model of the air puff test in the human cornea

We present a numerical model of a contactless test commonly used to assess the biomechanics of the human cornea. The test, consisting in a rapid air jet applied to the anterior surface of the cornea, is controversial. Although the numerous studies documented in the literature have not been able yet to clarify its relevance as a diagnostic tool, the test has the potential to be combined with inverse analysis procedures to characterize the parameters of numerical models of the cornea. With the final goal of employing the air puff test in advanced material identification algorithms, here we propose to model the cornea with standard finite elements and the fluids filling the anterior chamber of the eye with a meshfree discretization. The interaction between moving fluids and deforming cornea is accounted for by modifying the interface boundary conditions of both fluid and solid. The proposed model represents the first fully 3D example of an aqueous-cornea fluid-solid interaction analysis which uses a robust meshfree approach for the fluid. Although we restrict our scope to isotropic nonlinear materials, numerical results confirm the undeniable importance of including internal fluids in the simulation of the air puff test. Thus the proposed approach stands as a procedural paradigm for the identification of the mechanical parameters of the human cornea.

Air Ultrasonic Signal Localization with a Beamforming Microphone Array

Nondestructive testing methods are used to inspect and test materials and components for discontinuities or differences in mechanical characteristics. Phased array signal processing techniques have been widely used in different applications, but less research has been conducted on contactless nondestructive testing with passive arrays. This paper presents an application of beamforming techniques analysis using a passive synthetic microphone array to calculate the origin and intensity of sound waves in the ultrasonic frequency range. Acoustic cameras operating in the audible frequency range are well known. In order to conduct measurements in higher frequencies, the arrangement of microphones in an array has to be taken into consideration. This arrangement has a strong influence on the array properties, such as its beam pattern, its dynamics, and its susceptibility to spatial aliasing. Based on simulations, optimized configurations with 16, 32, and 48 microphones and 20 cm diameter were implemented in real experiments to investigate the array resolution and localize ultrasonic sources at 75 kHz signal frequency. The results show that development of an ultrasonic camera to localize ultrasonic sound sources is beneficial.

Wafer-Level Contactless Testing Based on UHF RFID Tags With Post-Process On-Chip Antennas

This brief demonstrates a fully contactless wafer-level testing based on UHF radio identification (RFID) technology enriched by high-quality on-chip antenna. The antenna, which uses exactly the same tag IC area (i.e., 0.45 mm2), exploits a low-cost post-process consisting of a thick dielectric layer and a copper metal, thus significantly improving the quality factor with respect to a standard CMOS implementation. Contactless wafer-level testing of a tag array is performed by simultaneous inductive coupling with a customized near-field reader. With a 27-dBm standard UHF RFID reader, a reading range up to 2.5 mm is demonstrated at 865 MHz. Anti-collision algorithm and memorized x–y device coordinates allow IC identification on the wafer under test to be achieved. Thanks to its cost-effectiveness, the proposed approach can be easily extended to general purpose IC contactless testing.