Shunichi Futatsumori

A Novel Assessment Methodology for the EMI Occurrence in Implantable Medical Devices Based Upon Magnetic Flux Distribution of RFID Reader/writers

With respect to the EMI affecting implantable medical devices caused by radio frequency identification reader/writers (RFID R/W), experimental investigations are conducted to develop a risk assessment methodology based upon the measurement of the EMF distribution around RFID R/W. First, fundamental EMI occurrence mechanisms of implantable- cardiac pacemakers and -cardioverter-defibrillators (ICD) are described. Secondly, the characteristics of the radio wave emitted by the RFID R/W are described. Next, EMI test experiments and measurements of the field distributions are performed. Then, a novel experimental assessment methodology is proposed. The EMI characteristics derived from magnetic flux distributions are compared with the experimental results to confirm the effectiveness of the proposed methodology. Finally, it is shown that the probability of EMI occurrence can be estimated using the statistical processing of the proposed methodology.

76.5 GHz millimeter-wave radar for foreign objects debris detection on airport runways

The paper is a joint work between the LEAT (France) and the ENRI (Japan) in the framework of a Sakura project supported by the JSPS and the French Ministry of Foreign Affairs. The purpose is the study of a FOD (Foreign Object Debris) detection system on airport runways. A FM-CW mm-Wave radar working between 76.25 and 76.75 GHz is used together with a high directivity printed reflectarray. Measurement results show detection capabilities of a -20 tlBsm cylinder up to 35 m which is 10 m less than the FAA recommendations. Antenna improvements are discussed for reaching the requirements and system performance as well as the use of calibration objects.

In vitro Assessment of Electromagnetic Interference due to Low-Band RFID reader/writers on Active Implantable Medical Devices

Introduction: The electromagnetic interference (EMI) of active implantable medical devices (AIMDs) due to 125–135 kHz and HF (13.56MHz) radio‐frequency identification (RFID) reader/writers are discussed based on in vitro experiments. The purpose of this paper is to clarify the detailed EMI occurrence conditions of both implantable cardiac pacemakers and implantable cardioverter defibrillators (ICDs) when used in proximity to commercial lowband RFID reader/writers.

Design and Field Feasibility Evaluation of Distributed-Type 96 GHz FMCW Millimeter-Wave Radar Based on Radio-Over-Fiber and Optical Frequency Multiplier

Foreign object debris (FOD) on airport runways must be removed immediately. To detect small debris, we proposed and developed an optically-connected distributed-type 96 GHz millimeter-wave radar system based on radio-over-fiber (RoF) technology and an optical fiber network. The proposed distributed-type radar system offers both improved FOD detection characteristics and cost performance. This paper details the design and field feasibility evaluation of the 96 GHz frequency-modulated continuous wave radar system that uses RoF and an optical frequency multiplier. Firstly, the problem of long distance RoF transmission, which limits the practical use of the RoF networked radar system in the airport environment, is discussed. Secondly, the concept and architecture of the millimeter-wave radar system are discussed and demonstrated focusing on its use in actual airports. Then, the results of a field experiment are shown to confirm the feasibility of the radar system. Finally, the effectiveness of the high-speed signal processing and generation circuits inside the central unit is evaluated at an actual airport based on the results of non-coherent and coherent signal integration.

Microwave shielding and polarization characteristics of carbon fiber reinforced plastic laminates with unidirectional materials

The electromagnetic shielding and polarization characteristics of carbon fiber reinforce plastics (CFRP) based on unidirectional (UD) materials are determined by experiments. The UD CFRP laminates have single direction carbon fibers, which behave the same as wire-grid structures. The measured transmission coefficient for the 1 ply UD CFRP laminate is about -2dB, when the direction of the carbon fiber is perpendicular to the incident wave. The polarization ratio is more than 20dB for most frequency points. In addition, it is confirmed that the transmission coefficient can be controlled by rotating the UD CFRP laminates.

Precise Measurement of IMD Behavior in 5-GHz HTS Resonators and Evaluation of Nonlinear Microwave Characteristics

The intermodulation distortion (IMD) of a 5-GHz HTS resonator is precisely measured and a nonlinear analysis is conducted. When designing a radio communication system that uses an HTS microwave device, the devices IMD characteristic is one of the most important problems that must be quantitatively evaluated. The amplitudes of third-order IMD (IMD3) and higher-order IMD, which are generated in an HTS resonator given a two-tone fundamental signal, are measured in detail using a fundamental signal cancellation circuit. Moreover, the relative phase of IMD3 is obtained by using a novel measurement system constructed around a reference IMD3 generator. The measured IMD3 phase shows a drastic change in a relatively low IMD3 amplitude region. In addition, the measured resonator exhibits strong higher-order IMD. A nonlinear evaluation using complex power series representation confirms that the drastic phase change may be due to the higher-order distortions present in IMD3.

Design and construction methodology of 96 GHz FMCW millimeter-wave radar based on radio-over-fiber and optical frequency doubler

To detect small debris on the airport surface, the optically-connected distributed-type 96 GHz millimeter-wave radar system, which is based on radio-over-fiber (RoF) technology and an optical fiber network, has been proposed and developed. Such foreign object debris (FOD) is required to be removed immediately. The distributed-type radar system enables the improvement of both the FOD detection and cost performance. In this paper, design and construction methodology of the 96 GHz frequency-modulated continuous wave radar system based on the RoF and optical frequency doubler is discussed. The architecture of the millimeter-wave radar system, which is designed to enable a long distance RoF transmission, is demonstrated. In addition, the effectiveness of the high-speed signal processing circuit inside the central unit is evaluated at an actual airport.

Experimental feasibility study of 96 GHz FMCW millimeter-wave radar based upon radio-over-fiber technology-fundamental radar reflector detection test on the Sendai airport surface-

Based on radio-over-fiber (RoF) technology, we have proposed a novel architecture foreign object debris (FOD) detection system. The FODs on the airport surface may cause damage to aircraft and must be immediately removed. The optically-connected millimeter-wave radar with separated front-ends enables both low-cost and high-detection performance. In this paper, the feasibility and effectiveness of the 96 GHz optically-connected millimeter-wave radar is experimentally confirmed through the target detection test on the airport surface. The distributed millimeter-wave radar system, which is connected by the RoF converter, is fabricated. In addition, the radar reflectors, which are located on the apron of the Sendai airport, are successfully detected by the radar system.

Evaluation of microwave shielding characteristics of quasi-isotropic carbon fiber reinforced plastic laminates based on unidirectional materials

The microwave shielding characteristics of quasi-isotropic carbon fiber reinforced plastics (CFRP) based on unidirectional (UD) materials are experimentally evaluated. First, fundamental characteristics of a UD CFRP laminate and a quasi-isotropic CFRP laminate are discussed. Second, shielding and polarization characteristics of a simple UD CFRP laminate are measured between 400 MHz and 6 GHz. The UD CFRP laminate, which has a same fiber direction, operates as a wire-grid and has more than 30 dB polarization ratio. Then, the dielectric constants of the fabricated CFRP laminate are measured by using the impedance analyzer. However, it was not suitable to describe whole wire-grid characteristics of the UD CFRP laminates. Finally, the measurement result of the quasi-isotropic CFRP laminate shows more than 40 dB shielding characteristics, which is almost the same as the dynamic range of the measurement system.

An experimental validation of a detailed numerical model for predicting implantable medical devices EMI due to low-band RFID reader/writers

The numerical assessment methodology of RFID/IMD-EMI was confirmed based on the result of the in-vitro experiments and the numerical analyses. The maximum interference distances obtained by the experiments and the FDTD analysis agreed very well. The good repeatability of the experiments and detailed modeling in the analyses achieve this high accuracy estimation. These results clarify the interference voltages due to the magnetic field generated around the low-band RFID reader/writer and they can be estimated by using precise and detailed analysis.