Hitachi, Ltd.

Kenji Imamoto

Naoki Shibata

Dai Watanabe

Yoshihito Sato

Keiji Maekawa

Yoichi Sugita

Keiichi Katsuta

Yoshinori Okura

Yusuke Nakanishi

Motonari Suzuki

Takayoshi Nishino

Kazuhiro Sanjo

Kenichi Sakai

In a railway signalling system which transmits a control order to an on-board signalling system by a trackside signalling system, the on-board signalling system being mounted on a train running on a line and the control order being compliant with a signalling system of the line, the present invention allows the train to run through into lines with different signalling systems using a single on-board signalling system. When the train enters a line with a different signalling system from a current line, the on-board signalling system installs a train control application program compliant with the signalling system of the entering line. Then, the on-board signalling system executes the train control application program, allowing the train to be controlled on the entering line according to a control order created by the trackside signalling system of the entering line.

Railway signalling system and on-board signalling system

A technique is offered which is adapted for optimization computations and which makes it possible to carry out an estimation of the state of propagation of radio waves quickly and accurately during a search for the locations of wireless stations. During the optimization computations, sending points and receiving points are set using a parameter search technique. Propagation paths are computed using a far-field approximation technique for Maxwell's equations. A propagation path leading to a local area where the accuracy is low with the far-field approximation technique is extracted from the computed paths. The state of scattering previously calculated using a numerical analysis technique for Maxwell's equations is reflected in the extracted path to modify the propagation path. The communication characteristics of the modified path are evaluated. The steps S-Sare performed repeatedly a given number of times. A sending point and a receiving point producing optimum communication characteristics are output.

Apparatus and method for searching for wireless station locations

Growing community of inventors

Hitachi, Japan

Kenji Imamoto