Mitsubishi Denki Kabushiki Kaisha

Other

Tadamasa Fukae

Tadatomi Ishigami

Toyofumi Tani

Norihiro Tamiya

Hiroshi Sato

Takashi Kawakami

Hiroshi Noda

Yoshihiko Utsui

Hiroyuki Somiya

Kenji Morihara

An obstacle detection system includes a leaky transmission path, a leaky receiving path opposite to the leaky transmission path, a spread spectrum signal generator connected to an end of the leaky transmission path and generating a spread spectrum signal for radiation from the leaky transmission path to detect an obstacle. A correlator is connected to an end of the leaky receiving path to calculate a level of correlation between a reference spread spectrum signal and a spread spectrum signal received by the leaky receiving path. A detector detects an obstacle in accordance with a change in the level of correlation calculated by the correlator.

Obstacle detection device and obstacle detection system

A vehicle borne transmitter transmits a spread spectrum transmit signal which is pseudo (PN) encoded. The transmitted signal is reflected off of a reflector on known position which may be a highway guardrail, tunnel wall, or the like. The reflected signal is detected by a receiver in the vehicle and a pseudo noise code (PN code) is synchronized to the reflected signal to accomplish maximum correlation. The phase delay between the transmitted PN code and received PN code is thereby utilized to determine the distance between the vehicle and reflector to maintain the vehicle in the center of a roadway lane. Roadway transponders may be periodically located adjacent the roadway and will be responsive to the vehicle borne interrogation signal. The periodically located transducers produce a reply signal including a PN code and imbedded data which data may represent transponder ID and position, roadway or map data, or other data which is desirable to transmit between the transducer and the vehicle travelling the highway.

Automated highway tracking and communication system and method

In an automated roadway system having transponders or data-stations spaced at known positions along the roadway, a vehicle mounted system determines the position of a vehicle moving along the roadway. A vehicle borne transmitter transmits a spread spectrum transmit signal which is pseudo (PN) encoded. The transmitted signal is received by the transponder which emits a reply signal back to a vehicle borne receiver. The receiver also receives a second signal which may be a reply signal from the same transponder or a reply signal from an adjacent transponder. The system then measures a time difference between transmission of the vehicle originated interrogation signal and receipt of its corresponding reply signal to determine the distance between the vehicle and the transponder or reflector. Based on the determined distances, the positions of the transponders and the distance that the vehicle has traveled during its communications, the position of a vehicle is determined using triangulation methods. The interrogation signals may be spread spectrum signals that are pseudo-random (PN) encoded. When the signal is detected by a receiver in the transponder or in the vehicle receiver, the PN code is synchronized to the incoming signal to accomplish maximum correlation. The phase delay between the transmitted PN code and received PN code is used to determine the distances between the vehicle and the transponder. The periodically located transponders produce a reply signal including a PN code and embedded data which represents the transponder identification and its position, or other data which is desirable to transmit between the transponder and the vehicle traveling the roadway.

Moving object high-accuracy position locating method and system

A combined diversity receiving apparatus comprises first mixers for mixing receiving signals from plural antennas with a signal from a feedback circuit, band-pass filters connected to outputs of the first mixers and having a band width to pass a random phase component due to fading and a main component of a modulation signal among received signals, second mixers for mixing output signals of the band-pass filters with the received signals, a coupler for combining outputs of the second mixers, and a feedback circuit for feeding back the output signal of the coupler to the first mixers.

Combined diversity receiving apparatus

Growing community of inventors

Tokyo, Japan

Tadamasa Fukae