TIME-DIVISION MULTIPLEX MOBILE COMMUNICATION SYSTEM

• US 3,628,147 A
• Filed: 12/09/1969
• Issued: 12/14/1971
• Est. Priority Date: 12/09/1969
• Status: Expired due to Term

• Current Assignee: Makino Kenichi
• Original Assignee: Makino Kenichi
• Inventors: MAKINO KENICHI
• Application Number:
  US04/883,448
• Time in Patent Office: 735 Days
• US Class Current: 370/315
• CPC Class Codes: B61L 27/20 Trackside control of safe travel of vehicle or train, e.g. braking curve calculation
• CPC Class Codes: B61L 3/225 using separate conductors along the route
• CPC Class Codes: H04J 3/08 Intermediate station arrangements, e.g. for branching, for tapping-off

Abstract

A time-division multiplex mobile communication system allowing communications to be made between a plurality of railroad trains travelling on a predetermined railroad line and a central base station through a plurality of repeater stations set up at a substantially equal distance along the line, which comprises means for carrying out communications between the central base station and each repeater station by a series of high-speed timedivision multiplex signals, means for allowing each repeater station to translate series of high-speed pulses included in the signals thus transmitted which is directed to the repeater station into a series of slow pulses and modulating by the translated slow pulses a carrier wave allotted to each train which has as high a frequency as possible and radiating the output signal to each corresponding train through a radiation transmission line, means for allowing the supplied signals to be demodulated at each corresponding train, means for allowing return signals consisting of a series of slow pulses prepared by each train separately from the demodulated signals to be transmitted in a reverse direction to the preceding case, namely, from the radiation transmission line to each repeater station, means for allowing the return signals to the central base station to be translated into a series of high-speed pulses at each corresponding repeater station and inserting the translated highspeed pulses into that of the time slots associated with the series of time-division multiplex pulses which is allotted to other repeater stations so as to be sent back to the central base station and means for bringing a repeater station to be prepared to have communication links between base station and trains existing in adjacent repeater sections and to complete uninterrupted communications at the moment the trains enter said repeater section.

Claims

1. A time-division multiplex mobile communication system allowing communication between movable objects trAvelling on a prescribed service line and a central base station to be conducted through a plurality of repeater stations set up at a substantially equal distance along said service line, which comprises a first means for carrying out communication from said central base station to each repeater station by a series of high-speed time-division multiplex pulse codes, a second means for allowing each repeater station to translate those of said series of high-speed pulse codes supplied thereto which are particularly converted to itself into a series of slow pulse codes, modulate carrier waves having as high a frequency as possible allotted to each movable object in its charge by said slow pulse codes and supply through a radiation transmission line said modulated signals to said movable object, a third means installed in said movable object for demodulating signals thus supplied thereto, a fourth means for allowing return signals consisting of slow pulse codes prepared by each movable object separately from said demodulated signals to be supplied reversely to each repeater station through said radiation transmission line, and a fifth means installed in each repeater station for translating said slow speed signals directed to the central base station into high-speed pulse codes and sending said translated signals back to the central base station.

2. The communication system according to claim 1 wherein said return signals from each repeater station are sent back to the central base station by being inserted into that of the time slots associated with said series of time-division multiplex pulse codes which is allotted to each repeater station and has now become vacant after drop out and demodulation by said second means.

3. The communication system according to claim 1 wherein reception by each repeater station according to said second means of those of a series of time-division multiplex pulse codes transmitted by the central base station which are particularly directed to itself is carried out by controlling the bias voltage of a diode.

4. The communication system according to claim 1 wherein supply of high-speed pulse codes by said second and fourth means is made at a speed corresponding to the code bit frequency forming said series of time-division multiplex pulse codes and supply of said series of slow pulse codes by said two means is conducted at a speed corresponding to a fraction of the total code bits forming a series of signals for each movable object as compared with said series of high-speed pulse codes.

5. The communication system according to claim 2 wherein supply of high-speed pulse codes by said second and fourth means is made at a speed corresponding to the code bit frequency forming said series of time-division multiplex pulse codes and supply of said series of slow pulse codes by said two means is conducted at a speed corresponding to a fraction of the total code bits forming a series of signals for each movable object as compared with said series of high-speed pulse codes.

6. The communication system according to claim 2 wherein return signals from each repeater station to the central base station are inserted into a time slot allotted to each repeater station by controlling the bias voltage of said diode.

7. A time-division multiplex mobile communication system allowing communication between movable objects traveling on a predetermined service line and a central base station to be performed through a plurality of repeater stations set up at a substantially equal distance along said service line, which comprises means for bringing the succeeding one of two adjacent repeater stations to a communicable state at the moment each movable object passes over the junction of two adjacent repeater stations, wherein said means allows the width of a gate for selecting a required one form among a series of time slots previously allotted to each repeater station in a predetermined order to be broadened to an extent corresponding to more than two time slots so aS to permit a given repeater section of movable objects on which each repeater station should give information to overlap the immediately following repeater section.