An optical bus type communication system

Claim 2

An optical bus type communication system comprising; a first bus type transmission line (20) consisting of optical fiber, a light source (10), provides at the one end of said bus type transmission line (20), for sending an optical signal of at least constant level to said bus type transmission line (20), a plurality of optical switches (11 - 1n) inserted to said bus type transmission line (20), a plurality of terminal interfaces (1 - n), provided at corresponding optical switches (11 - 1n), respectively, for digitally modulating optical signals of constant level which passes through said bus type transmission line (20) by switching control of said optical switches (11 - 1n) corresponding to the data to be sent to said bus type transmission line (20), and a main station (41), provided at the other end of said bus type transmission line (20), having a receiving means (42) for receiving said digitally modulated optical signal.

Claim 3

An optical bus type communication system according to claim 1, further comprising; a second bus type transmission line (40) consisting of an optical fiber, and sending means (43), provided at said main station (41), for sending an optical signal from the other end of said second bus type transmission line (40), a plurality of first optical couplers (21 - 2n), inserted to said second bus type transmission line (40) corresponding to said terminal interface (1 - n), respectively, said terminal interfaces (1 - n) receive the optical signal being transmitted through said second bus type transmission line (40) via corresponding first optical couplers (21 - 2n).

Claim 4

An optical bus type communication system according to claim 2, wherein said optical signal on said first and second transmission lines (20, 40) are signal in unit of frame including the frame synchronous pattern and monitor bit, and said master station (41) has a return means for loading the monitor bit received from said first bus type transmission line (20) to the monitor bit of said second bus type transmission line (40).

Claim 5

An optical bus type communication system according to claim 3, wherein said terminal interfaces (1 - n) have control means for controlling the corresponding optical switches (21 - 2n) and for loading specific pattern to said monitor bit when said terminal interfaces (1 - n) make access to the frame of said first bus type transmission line (20), and compare means for receiving the monitor bit returned to the second transmission line (40) from said main station (41) and for comparing said monitor bit with said specific pattern.

Claim 6

An optical bus type communiation system according to claim 4, wherein said terminal interfaces (1 - n) discriminate whether the right to use said frame can be obtained or not from the comparison result of said comparison means.

Claim 7

An optical bus type communication system according to claim 3, further comprising; a receive means (51), provided at the other end of said second bus type transmission line (40), for receiving the optical signal transmitted from said main station (41), and a return means (51), provided at the other end of said second bus type transmission line (40), for modulating said light source with the frame synchronous pattern of the received optical signal and for returning said frame synchronous pattern to said first transmission line (20).

Claim 8

An optical bus type communication system according to claim 6, further comprising; a plurality of second optical couplers (31 - 3n), inserted to the first bus type transmission line (20) corresponding to said terminal interfaces (1 - n).

Claim 9

An optical bus type communication system according to claim 7, wherein each of said second optical couplers (31 - 3n) is inserted in the side of said light source of each optical switch (11 - 1n), and said terminal interfaces (1 - n) have synchronization means for synchronizing with the frame synchronous pattern, on said second transmission line (40), received through said first optical coupler (21 - 2n), and for synchronizing with the frame synchronous pattern, on said first transmission line (20), received through said second optical coupler (31 - 3n), and timing control means for switching said optical switches based on the timing signal from said synchronization means.

Claim 10

An optical bus type communication system comprising; a bus type transmission line consisting of optical fiber, a sending/receiving means, provided at the one end of said bus type transmission line, having a receive means for receiving first optical signal from said bus type transmission line and a send means for sending second optical signal of at least constant level to said bus type transmission line, a main station, provided at the other end of said bus type communiation line, having a receive means for receiving second optical signal from said bus type transmission line and a send means for sending first optical signal to said bus type transmission line, a plurality of optical switches inserted to said bus type transmission line, a plurality of first optical couplers inserted to said bus type transmission line, and terminal interfaces having modulation means for digitally modulating the second optical signal of constant level passing through said bus type transmiss­ion line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and receive means for receiving the first optical signals on said bus type transmission line through said optical couplers; whereby transmiss­ion of the first and the second optical signal is realized on the time division basis.

Claim 11

An optical bus type communication system comprising; a bus type transmission line consisting of optical fiber, a sending/receiving means, provided at the one end of said bus type transmission line, having a receive means for receiving first optical signal from said bus type transmission line and a send means for sending second optical signal of at least constant level to said bus type transmission line, a main station, provided at the other end of said bus type communiation line, having a receive means for receiving second optical signal from said bus type transmission line and a send means for sending first optical signal to said bus type transmission line, a plurality of optical switches inserted to said bus type transmission line, a plurality of first optical couplers inserted to said bus type transmission line, and terminal interfaces having modulation means for digitally modulating the second optical signal of constant level passing through said bus type transmiss­ion line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and receive means for receiving the first optical signals on said bus type transmission line through said optical couplers; whereby transmiss­ion of the first and the second optical signal is realized on the time division basis.

Claim 12

An optical bus type communication system according to claim 9, wherein said sending/receiving means is provided with LED used as the send means and the receive means in common.

Claim 13

An optical bus type communication system according to claim 9, wherein said main station is provided with the LED used as the send means and the receive means in common.

Claim 14

An optical bus type communication system according to claim 9, wherein said optical couplers branch optical signal sent from the main station to said terminals and also branch optical signal sent from said send/receive means to said terminals.

Claim 15

An optical bus type communication system according to claim 9, wherein said first and second optical signals on said bus type transmission line are signals in unit of frame including the frame synchro­nous pattern and monitor bit, and said master station has return means for loading the monitor bit of the second optical signal to the monitor bit of the first optical signal.

Claim 16

An optical bus type communication system according to claim 13, wherein said terminal inter­faces have control means for controlling the corresponding optical switches and for loading specific pattern to said monitor bit of the second optical signal when said terminal interfaces make access to the frame of the second optical signal, and compare means for receiving the monitor bit of the first optical signal returned from said main station and for compar­ing said monitor bit with said specific pattern.

Claim 17

An optical bus type communication system according to claim 14, wherein said terminal inter­faces discriminate whether the right to use said frame of the second optical signal can be obtained or not from the comparison result of said comparison means.

Claim 18

An optical bus type communication system according to clailm 13, wherein said sending/receiving means further comprises a return means for modulating said second optical signal with the frame synchronous pattern of the first optical signal and for loading said frame synchronous pattern on said second optical signal transmission line.

Claim 19

An optical bus type communication system according to clailm 13, wherein said sending/receiving means further comprises a return means for modulating said second optical signal with the frame synchronous pattern of the first optical signal and for loading said frame synchronous pattern on said second optical signal transmission line.

Claim 20

An optical bus type communication system according to claim 16, further comprising; a plurality of second optical couplers, inserted to the bus type transmission line corresponding to said terminal interfaces.

Claim 21

An optical bus type communication system according to claim 17, wherein each of said second optical couplers is inserted in the side of said send­ing/receiving means of each optical switches and said terminal interfaces have synchronization means for synchronizing with the frame synchronous pattern of said first optical signal, received through said first optical coupler, and for synchronizing with the frame synchronous pattern of said second optical signal, received through said second optical coupler, and timing control means for switching said optical switches based on the timing signal from said synchro­nization means.

Claim 22

An optical bus type communication system com­prising; a bus type transmission line consisting of optical fiber, a sending/receiving means, provided at the one end of said bus type transmission line, having receive means for receiving first optical signal from said bus type transmission line in the first mode and send means for sending second optical signal of at least constant level to said bus type communication line in the second mdoe, a main station, provided at the other end of said bus type communication line, having receive means for receiving second optical signal from said bus type transmission line in the second mode and send means for sending first optical signal of at least constant level to said bus type transmission line in the first mode, a plurality of optical switches inserted to said bus type transmission line, a plurality of first optical couplers inseted to said bus type transmission line, and terminal interfaces having modulation means for digitally modulating the second optical signal of constant level passing through said bus type transmiss­ion line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and receive means for receiving the first optical signals on said bus type transmission line through said optical couplers; said first and second modes are on the time division basis, said first and second optical signals are signals in unit of frame including the frame synchronizing pattern and channel for communication between said terminal interfaces, each of said terminal interfaces loads sending data, for the terminal interfaces at down the bus type transmission line there from in the first or second mode on said channel by controlling corresponding optical switches, and said terminal interfaces at down the bus type transmission line receive said sending data on said channel via corresponding optical couplers.

Claim 23

An optical bus type communication system com­prising; a bus type transmission line consisting of optical fiber, a sending/receiving means, provided at the one end of said bus type transmission line, having receive means for receiving first optical signal from said bus type transmission line in the first mode and send means for sending second optical signal of at least constant level to said bus type communication line in the second mdoe, a main station, provided at the other end of said bus type communication line, having receive means for receiving second optical signal from said bus type transmission line in the second mode and send means for sending first optical signal of at least constant level to said bus type transmission line in the first mode, a plurality of optical switches inserted to said bus type transmission line, a plurality of first optical couplers inseted to said bus type transmission line, and terminal interfaces having modulation means for digitally modulating the second optical signal of constant level passing through said bus type transmiss­ion line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and receive means for receiving the first optical signals on said bus type transmission line through said optical couplers; said first and second modes are on the time division basis, said first and second optical signals are signals in unit of frame including the frame synchronizing pattern and channel for communication between said terminal interfaces, each of said terminal interfaces loads sending data, for the terminal interfaces at down the bus type transmission line there from in the first or second mode on said channel by controlling corresponding optical switches, and said terminal interfaces at down the bus type transmission line receive said sending data on said channel via corresponding optical couplers.

Claim 24

An optical bus type communication system according to claim 19, wherein said first and second optical signals on said bus type transmission line include monitor bit, said terminal interfaces have control means for controlling the corresponding optical switches and for loading specific pattern to head of said channel of the first and second optical signals when said terminal interfaces make access to the channel of the first and second optical signals, and compare means for receiving the monitor bit of the first and second optical signal returned and for com­paring it with said specific pattern, and said main station and said sending/receiving means have return means for loading the received said specific pattern to said monitor bit and for returning said specific pattern.

Claim 25

An optical bus type communication system com­prising; first and second type transmission lines consist­ing of optical fiber, a sending/receiving means, provided at the one end of said first and second bus type transmission lines, having receive means for receiving first optical signal from said second bus type transmission line in the first mode and send means for sending second optical signal of at least constant level to said first bus type communication line in the second mode, a main station, provided at the other end of said first and second bus type communication lines, having receive means for receiving second optical signal from said first bus type transmission line in the second mode and send means for sending first optical signal of at least constant level to said second bus type trans­mission line in the first mode, a plurality of optical switches inserted to said first and second bus type transmission lines, a plurality of optical couplers inserted to said first and second bus type transmission lines, and terminal interfaces having modulation means for digitally modulating the second and first optical signals of constant level passing through said first and second bus type transmission lines by switching control of said optical switches corresponding to the data to be sent to said fist or second bus type transmission line, and receive means for receiving the second and first optical signlas on said first and second bus tpye transmission lines through said optical couplers; said firt and second optical signals are signals in unit of frame including the frame synchronizing pattern and channel for communication between said terminal interfaces, each of said terminal interfaces loads sending data, for the terminal interfaces at down the first and second bus type transmission lines therefrom in the second or first mode on said channel by controlling corresponding optical switches, and said terminal interfaces at down the first and second bus type transmission lines receive said sending data, in the second and first mode, on said channel via corresponding optical couplers.

Claim 26

An optical bus type communication system com­prising; first and second type transmission lines consist­ing of optical fiber, a sending/receiving means, provided at the one end of said first and second bus type transmission lines, having receive means for receiving first optical signal from said second bus type transmission line in the first mode and send means for sending second optical signal of at least constant level to said first bus type communication line in the second mode, a main station, provided at the other end of said first and second bus type communication lines, having receive means for receiving second optical signal from said first bus type transmission line in the second mode and send means for sending first optical signal of at least constant level to said second bus type trans­mission line in the first mode, a plurality of optical switches inserted to said first and second bus type transmission lines, a plurality of optical couplers inserted to said first and second bus type transmission lines, and terminal interfaces having modulation means for digitally modulating the second and first optical signals of constant level passing through said first and second bus type transmission lines by switching control of said optical switches corresponding to the data to be sent to said fist or second bus type transmission line, and receive means for receiving the second and first optical signlas on said first and second bus tpye transmission lines through said optical couplers; said firt and second optical signals are signals in unit of frame including the frame synchronizing pattern and channel for communication between said terminal interfaces, each of said terminal interfaces loads sending data, for the terminal interfaces at down the first and second bus type transmission lines therefrom in the second or first mode on said channel by controlling corresponding optical switches, and said terminal interfaces at down the first and second bus type transmission lines receive said sending data, in the second and first mode, on said channel via corresponding optical couplers.

Claim 27

An optical bus type communication system according to claim 21, wherein said second and first optical signals on said first and second bus type transmission line include monitor bit, said terminal intefaces have control means for controlling the corresponding optical switches for loading specific pattern to head of said channel of the first and second optical signal when said terminal interfaces made access to the channel of the first and second optical signals, and compare means for receiving the monitor bit of the first and second optical signal returned and for comparing the monitor bit with said specific pattern, and said main station and said sending/receiv­ing means have return means for loading the received specific pattern to said monitor bit and for returning said specific pattern.

Claim 28

An optical bus type communication system comprising; a bus type transmission line consisting of optical fiber bent in the form of letter U, send means, provided at the one end of said bus type transmission line, for sending optical signal of costant level and modulated optical signal to said bus type transmission line, receive means, provided at the other end of said bus type transmission line, for receiving said optical signal from said bus type transmission line, a plurality of optical swithces inserted to said bus type transmission line, a plurality of optical couplers inserted to said bus type transmission line, and terminal interfaces for digitally modulating the optical signal of constant level which passes through said bus type transmission line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and for receiving the modulated optical signal in said bus type transmission line through said optical couplers; whereby said send means transmit the modulated optical signal of constant level on the time division basis.

Claim 29

An optical bus type communication system comprising; a bus type transmission line consisting of optical fiber bent in the form of letter U, send means, provided at the one end of said bus type transmission line, for sending optical signal of costant level and modulated optical signal to said bus type transmission line, receive means, provided at the other end of said bus type transmission line, for receiving said optical signal from said bus type transmission line, a plurality of optical swithces inserted to said bus type transmission line, a plurality of optical couplers inserted to said bus type transmission line, and terminal interfaces for digitally modulating the optical signal of constant level which passes through said bus type transmission line by switching control of said optical switches corresponding to the data to be sent to said bus type transmission line, and for receiving the modulated optical signal in said bus type transmission line through said optical couplers; whereby said send means transmit the modulated optical signal of constant level on the time division basis.