Mitsubishi Electric

About: Mitsubishi Electric is a company organization based out in Ratingen, Germany. It is known for research contribution in the topics: Signal & Voltage. The organization has 23024 authors who have published 27591 publications receiving 255671 citations. The organization is also known as: Mitsubishi Electric Corporation & Mitsubishi Denki K.K..

Enhancement of spectral separation performance for ASTER/SWIR

Abstract: The mechanism of the crosstalk phenomena in the ASTER/SWIR subsystem, which has six bands in the wavelength of 1.6 - 2.43 micrometers region, is investigated. It is found that the incident light to a detector array of the band 4 of the SWIR subsystem is reflected at an electrical wiring at the focal plane. It is transported to detectors of other bands by multiple reflections through the bandpass filter in front of detectors. By analyzing SWIR images around islands and peninsulas, crosstalk components in images are estimated. For this purpose, the crosstalk correction software is developed. Parameters of the crosstalk phenomena, i.e., the amount of stray light and the influential area of stray light, are determined by image analysis. It is found that the spectral separation performance of the SWIR subsystem is enhanced using the correction software in this study, which leads to more accurate spectral studies of SWIR images and is promising in exploiting natural resources.

A half-pel precision MPEG2 motion-estimation processor with concurrent three-vector search

Abstract: A half-pel precision MPEG2 motion estimation processor using a 0.5 /spl mu/m CMOS technology supports all prediction modes in MPEG2 including frame, field and dual-prime prediction, and estimates three vectors concurrently. The multiple processor configuration allows a search range expansion by /spl plusmn/127.5, keeping bus traffic constant. It integrates 850 K transistors in a 13.85 mm/spl times/13.55 mm silicon die. The observed maximum operating frequency is 75 MHz. At 40 MHz for NTSC, the peak computational power is 20 GOPS and the power dissipation is 1.9 W.

Smith–Purcell radiation experiment using a field-emission array cathode

Abstract: We have recently started an experiment on visible Smith–Purcell (SP) radiation to examine practical applicability of a field-emission array (FEA) cathode to compact free electron lasers, placing emphasis on safe operation of the cathode as well as beam quality. The electron beam was generated by a 5 cm long triode which employed either a single- or double-gated FEA. Accelerating voltages of up to −40 and −100 kV were applied to the cathode by a regulated power supply and a small Van der Graaff generator, respectively. A 25 μA beam of up to 45 keV was routinely produced and a 5 μA 80 keV beam was also attained. The beam passed through a 1 mm wide slit in the anode and grazed the surface of a 2.5 cm long replica grating with a period of either 0.56 or 0.83 μm. The SP radiation has not been identified owing to irrelevant luminescence caused by the beam at the grating. Still it was confirmed that the FEA cathode is adequately durable and electron beams generated therefrom are sufficiently stable to be used for systematic measurements of radiation.

Refrigerating/air conditioning system having refrigerant learage detecting function, refrigerator/air conditioner and method for detecting leakage of refrigerant

Abstract: A refrigerating/air conditioning system and a method for detecting leakage of refrigerant which can detect leakage of a trace of refrigerant automatically while performing air conditioning operation regardless of environmental conditions or installation conditions. The refrigerating/air conditioning system, where a refrigeration cycle is constituted by connecting an outdoor unit having a compressor, an outdoor heat exchanger and a restrictor with one or a plurality of indoor units having an indoor heat exchanger and a restrictor through interconnection piping, is provided with a means for judging leakage of refrigerant of the refrigeration cycle based on the past data about the quantity of refrigerant of the refrigeration cycle in the past, and new data about the quantity of refrigerant after performing stop and start of the refrigeration cycle a plurality of times since a moment in time in the past.

Space voltage vector-based new PWM method for large capacity three-level GTO inverter

Abstract: A novel pulse-width-modulation (PWM) method for a three-level inverter based on space voltage vectors is presented. This PWM method can minimize the harmonic components of the output voltage under the minimum pulse-width limitation gate turn-off thyristors (GTOs) and can also suppress the fluctuation of the neural point DC voltage. Experimental results demonstrate that the proposed PWM method is suitable for a large-capacity three-level GTO inverter applied to motor drives for steel rolling mills, railcars, etc. >