A physics-based dipole moment source reconstruction is proposed to estimate the near-field coupling between a liquid crystal display panel cellphone's cellular antenna. Based on understanding of current distribution source, magnetic reconstructed replace real radiation that located at edge flexible printed circuit board. To characterize from equivalent victim antenna, noise transfer coefficient proposed. The can be calculated scanning and direct measurements using wideband source. are...

In radio frequency interference study, equivalent dipole moments are widely used to reconstruct real radiation noise sources. Previous reconstruction methods, such as least square method (LSQ) and optimization affected by parameter selections, number locations of choices initial values. this paper, a new machine learning based source is developed extract the more accurately reliably. Based on near-field patterns, proposed can determine minimal their corresponding locations. Furthermore,...

In near-held scanning using H-held probes, E-held coupling is a major concern. suppression performance must be characterized before an probe can used for scanning. Common method of measurement involves measuring the in same location where strongest occurs. microstrip line traces, it assumed that this occurs right above center trace and less at all other locations across line. paper, we show maximum slightly offset from center. The to shielded such position leads differential-mode coupling,...

A method to optimize the IC placement in mobile devices from RF interference perspective is proposed. The coupling an antenna estimated by combining equivalent dipole moment source and reciprocity, which facilitates understanding of physics design insight for devices. Based on proposed method, optimal place noisy ICs can be quantitatively determined each frequency interest.

Ahstract- In this paper, the dipole-moment based reciprocity method is used to perform desense prediction and mitigation from DDR noise source nearby RF antenna. The signals between application processor memory IC. Radiation physics of analyzed by understanding current flow. Firstly, random nature using measurement data. Based on data, setup near field scanning further determined. procedures are decomposed into two steps: forward problem reverse problem. problem, approximately regarded as a...

Dipole moment model is widely used to represent real noise source estimate near field coupling between and the victim antenna. However, direct full wave simulation of large number dipole often very time-consuming. Also, another set needed if parameters change. A more scalable approach needed. In this paper, a transfer function based proposed solve issue. The method only needs one-time simulation. results obtained from can be reused for other cases same antenna structure used. will use...

As more compact designs and assembled function modules are utilized in modern electronic devices, radio-frequency interference (RFI) source reconstruction is becoming challenging because different noise sources may contribute simultaneously. This article presents a novel methodology to reconstruct multiple random on real-world product, including several double-data-rate (DDR) memory high-speed connector. The DDR located beneath heatsink cause noise-like signals, which renders phase...

Multiple digital ICs sharing ground plane have potential problems of noise interference to each other. Current distribution on the can introduce intra-system EMC issues, which possibly result in receiver desensitization issue wireless devices. In this paper, a method moment (MoM) based current reconstruction is proposed estimate plane. This requires phased resolved near field data for accurate reconstruction. The validated by numerical example. reconstructed from compared with simulation...

A transfer function based calculation method is proposed to estimate radio frequency interference (RFI) problems. The closed-form equations are analytically derived from Maxwell's and the reciprocity theorem. can clearly decompose RFI problem into two parts: noise source coupling antenna. Based on derivations, a concept quantify coefficient each unit dipole moment victim functions be easily obtained S-parameter measurements. validated through numeric simulations real cellphone experiments....

A method of moment (MoM)-based current reconstruction is proposed to estimate the surface density on ground plane. Current continuity property automatically enforced with Rao-Wilton-Glisson basis function. Both least square and optimization are utilized solve inverse problem obtain current. The successfully validated numeric simulations also a real-world measurement example. reconstructed distribution plane further used in typical radio frequency interference (RFI) example perform RFI...

In this paper, a de-embedding method is proposed to measure the impedance of an innovative O-shape spring contact, for frequency up 30 GHz. To allow be applied in practical situations, both conductor loss and discontinuity associated with junction are taken into account. Results obtained from validated using full wave simulation. simulation model, contact cut two pieces based on current flow paths, providing straightforward way understand why resonance exists profile connector. Lastly,...

The dipole moment-based reciprocity to model intra-system electromagnetic interference (EMI) in wireless devices is proposed this paper. In model, the decomposition method based on used calculate coupling voltage victim antenna. original noise source replaced by equivalent moments forward problem while fields locations of are scanned reverse problem. has been validated with full-wave simulations and measurements; it provides not only convenience estimate radio-frequency (RFI), but also...

This article proposes a novel radio frequency interference (RFI) mitigation method and applies it to real consumer electronic device. Through near-field scanning, an equivalent dipole moment of the noise source containing CPU DDR memory chip is reconstructed. The components victim Wi-Fi antenna are measured obtain transfer function. By determining relationship between near field, rotated by certain angle reduce RFI. Rotating RFI implemented in such way that does not compromise signal...

Infinitesimal electric and magnetic dipoles are widely used as an equivalent radiating source model in far field radiated emissions near coupling scenarios. In this paper, a hybrid method for physical dipole extraction based on genetic algorithm linear least square is proposed. It offers automatic flow to extract the without prior decision of type, position, orientation number dipoles. Compared with conventional method, can which close original minimize reduces optimization time more robust....

Heatsinks are widely used to dissipate heat in electronic devices. RF emission from heatsinks and ICs can cause radio frequency interference (RFI) issues. The existence of the heatsink affects coupling noise source victim antenna. In this paper, RFI problems analyzed by two methods using reciprocity theorem. first method, effect is combined with antenna derive transfer function. second be characterized both side on a closed 6-surface box. physical insights comparisons estimation based...

When a wireless device is connected to networks such as Wi-Fi and GSM, annoying noise in audible frequency range, named buzz noise, can appear the audio system. The characterization quantification of provide theoretical fundamental for solving this problem. It has been discovered that converted from radio (RF) signal through unexpected square-law demodulation microphone. Based on generation mechanism, paper developed two-port network model quantify RF coupling path conversion noise. results...

In a near-field scanning system, each element of the measurement chain contributes to thermal noise power density: probe, cables, amplifiers, and measuring instrument. The signal-to-noise ratio (SNR) is strongly affected by source output impedance, temperature, lossy transmission lines between probe amplifier noise, gain. By minimizing loss using ultralow-noise amplifiers (noise figure (NF) <; 0.5 dB), SNR improves >10 dB, compared setup 1-m cable 3-dB NF amplifier. A resonant that cooled...

When a device is communicating through wireless connections such as GSM or Wi-Fi, noise in audible range, called buzz noise, often generated an audio system and disturbs the signal quality. While problem has been found devices for long time, there little understanding of generation mechanism. In this paper, model proposed considering demodulation transfer function microphone IC front-end. The verified several experiments using recorded data tablet. Especially, caused by real Wi-Fi signals...

Unintended Electromagnetic interference (EMI) is a common occurrence in all consumer electronics, which can often fail compliance margins of FCC and/or CE, when best practices grounding, shielding and overall system integration are not followed. The measurement EMI for regulatory has been studied extensively there standard test labs certifies EMI. However, predicting the radiation from electronic device through simulation very challenging due to complexities involved modeling noise source....

In this paper, a dipole-moment based reciprocity method is applied to consumer electronic device. The dipole moment then used predict radio-frequency interference (RFI) from high-speed connector two nearby RF antennas. has 3D structure with data pins vertically-oriented, for which the near H field pattern around shows half magnetic pattern. This different typical complete patterns over planar printed PCB (printed circuit board) structures. To tackle problem, placed in full-wave simulation...

In modern mobile electronic systems, USB connector has been identified as one of the dominant noise sources for desense issues. this paper, coupled to Wi-Fi antenna from a is investigated. With assistance full-wave simulations, root cause non-ideal electrical connection between metal chassis and receptacle shell where it installed. The proposed radiation mechanism validated through measurements real tablet device, 15 dB level reduction observed with better grounding structure.

Equivalent dipole moments are widely used for noise source reconstruction in radio frequency interference (RFI) study. The equivalent sources usually extracted from measured near-field pattern. This paper introduces a machine learning based method to extract the moments. A convolutional neural network is trained perform multi-label classification determine type of locations obtained global averaging pooling layer. Then magnitude and phase dipoles can be calculated least square (LSQ)...

In this paper, an equivalent dipole moment method and full wave simulation are proposed to predict radiated spurious emissions (RSE). The is utilized in design of a practical electronic device. Based on near field patterns, the radiation physics 2.4GHz Wi-Fi transmitter harmonics device identified be magnetic moment. Reduction loop size proved effective reduce RSE 2.4 GHz. addition, 5 GHz simulated using solver methods discussed. Measured results also shown validate prediction mitigation methods.

Non-ideal ground structures in flexible printed circuit board, such as the meshed or discrete nets, can cause severe RFI to nearby antennas. Those RF radiators be modeled a set of equivalent dipole moment(s) when they are electrically small. Then, moment based reciprocity theorem applied estimate noise coupling level. In this article, practical methodology using is proposed identify multiple radiation sources real cellphone product. Multiple moments constructed with one-to-one correspondence...