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To avoid a trial and error adjustment for designing EMI filters, clarifying load impedance of operating condition, i.e., dynamic impedance of equipment is very useful. Therefore the need to a non-contact measurement method of the impedance connected to a wire harness is increasing rapidly. A measurement method using a network analyzer with two current probes was previously proposed. However, it was confirmed only up to 30 MHz. Many radio equipment operate above 30 MHz such as FM receivers and GPS receivers installed in vehicles. So increasing the measurement frequency is necessary in the auto industry. At first, we tried to expand the applicable frequency to 100 MHz, i.e., FM band. In this study, we applied the transmission line theory using the non-contact measurement method. Furthermore, in order to use the theory, the characteristic impedance and phase constant of the wire harness are required. So we made an additional measurement to estimate them.

Reducing the loss of the power control unit (PCU) in a hybrid vehicle (HV) is an important part of improving HV fuel efficiency. Furthermore the loss of power devices (insulated gate bipolar transistors (IGBTs) and diodes) used in the PCU must be reduced since this amounts to approximately 20% of the total electrical loss in an HV. One of the issues for reducing loss is the trade-off relationship with reducing voltage surge. To restrict voltage surge, it is necessary to slow down the switching speed of the IGBT. In contrast, the loss reduction requires the high speed switching. One widely known method to improve this trade-off relationship is to increase the gate voltage in two stages. However, accurate and high-speed operation of the IGBT gate control circuit is difficult to accomplish. This research clarifies a better condition of the two-stage control and designed a circuit that improves this trade-off relationship by increasing the speed of feedback control.

In gasoline direct injection (GDI) systems, various injection types are needed to reduce emissions and improve fuel consumption. This requires high-precision injection in the region in which the amount of injection is small. Achieving injection of a small amount of fuel using GDI solenoid injectors requires the use of the half-lift region. In this region, however, the variation in the injection amount tends to increase due to the variation in the lift behavior of the injectors, posing the problem of how to achieve high-precision injection. To reduce the variation, we analyzed the lift timing out of the injector current and voltage signal with the ECU in an attempt to adjust the amount of injection.

In the last decade, radar-based Advanced Driver Assistance Systems (ADAS) have improved safety of transportation. Today, the standardization of ADAS established by New Car Assessment Program (NCAP) is expected to expand its market globally. One of the key technologies of ADAS is the rear-side monitoring system such as Blind Spot Warning (BSW) and Closing Vehicle Warning (CVW). It is required to expand its detection range so that it can monitor not only nearside targets for BSW, but farther targets for CVW. These applications can be achieved using two radar sensors installed at rear-side corner of the vehicle. However, the expanded detection range causes undesirable target detections and decreases target recognition performance. In this paper, a novel solution to improve the performance using DCMP(Directional-Constrained Minimization of Power)-based Beamspace technology using Two-frequency continuous wave (2FCW also known as FSK) is introduced.

It is important that Advanced Driver Assistance Systems (ADAS) and Automated Driving Systems (AD) detect on-road objects, road vehicles and pedestrians. The typical detection devices mounted on ADAS and AD include a camera, a millimeter-wave radar and a Light Detection And Ranging (LiDAR). Since LiDAR can obtain accurate distance and fine spatial resolution due to its short wavelength, it is expected that small objects such as a tire can be detected. However, the conventional LiDAR is equipped with multiple light transmitters and light receivers such as avalanche photo diodes. This causes LiDAR system to be expensive and large in size. Aiming to reduce the cost and size of LiDAR, we employed Single-Photon Avalanche Diode (SPAD) which can be fabricated by CMOS process and easily arrayed. We also developed “Single Chip SPAD Array“ in which the two-dimensional array of SPAD and a signal processing block of range calculation were integrated into a single chip.

An important function of an Automated Driving (AD) system is to detect objects including vehicles and pedestrians on the road. Typical devices for detecting those objects include cameras, millimeter-wave RADAR, and light detection and ranging (LiDAR). LiDAR uses the flight time of a short-wavelength electromagnetic wave. Because of that LiDAR is expected to find even small objects such as tire fragments on a road in high resolution. The detection performance required for LiDAR depends on the operational design domain (ODD). For example, while a vehicle is travelling at high speeds, LiDAR needs to detect apparently small objects at long distances, and while it is travelling at low speeds, LiDAR has to detect objects over a wide angular range. Conventional LiDAR is developed to satisfy all requirements, providing performance including detection distance, resolution, and angle of view tends to expose issues such as cost and size when it is mounted onboard.

A Rear Cross Traffic Auto Brake (RCTAB) system has been developed that uses radar sensors to detect vehicles approaching from the right or left at the rear of the driver’s vehicle, and then performs braking control if the system judges that a collision may occur. This system predicts the intersecting course of approaching vehicles and uses the calculated time-to-collision (TTC) to control the timing of automatic braking with the aim of helping prevent unnecessary operation while ensuring system performance.

The adaptive cruise control (ACC) system reduces the workload of the driver. Lower cost and more precise control are the keys to successfully creating a market with the ACC system. A system that eliminates unexpected acceleration or deceleration caused by incorrect judgment is in high demand. From 1997, the laser radar ACC system has been produced for the domestic version of the Lexus LS400. It provides high recognition capability with a two-dimensional scanning system at an affordable price. Th millimeter wave radar ACC system can perform with better recognition capability, but is quite expensive. While many companies are developing millimeter wave radar ACC systems, we think our laser radar ACC system is superior.

The EMI, electromagnetic interference, is tested for automobiles and components by the method defined in the international standard, CISPR 25. Regarding the automobile test, the EMI from the component installed in the automobile is measured by the antenna of an automobile. On the other hand on the component test, the EMI from the component is measured by a mono-pole antenna set forward of the component. However, components sometimes fail the automobile test even if its passed the component test due to the difference of the method. In this case, the component has to be designed again to pass the automobile test. Therefore, the prediction method of the automobile test result is required. In this paper, we tried to modify the standard component test configuration to predict the automobile test result for a fuel pump system in AM frequency band.