公开(公告)号：DE69130160T2

公开(公告)日：1999-05-12

申请号：DE69130160

申请日：1991-12-27

Applicant: NEC CORP

Inventor： EDA MASAHIRO

IPC: H04J14/00 ,  H04B10/27 ,  H04B10/275 ,  H04J14/02 ,  H04L12/423 ,  H04L12/433 ,  H04L12/64 ,  H04L12/28 ,  H04B10/00

Abstract: A supervisory node (2) and non-supervisory nodes (3 through 9) are connected in a loop by an optical transmission path (1). Over the loop (1) are transferred optical signals having wavelengths of lambda l through lambda n. An access right control packet 10 is transferred in the loop at the optical wavelength of lambda l. A node performing data transmission by line exchange writes its own node address (SA), the destination address (DA) and transmit reservation in the header of the access right control packet 10, and sends the packet out on the optical transmission path. The supervisory node 2 having received this access right control packet writes the wavelength to be used ( lambda i) into the used wavelength field (UWL), and notifies the transmit and receive nodes of the choice of the wavelength. The transmit node sends data to the receive node by line exchange at the designated wavelength lambda i.

公开(公告)号：DE69130160D1

公开(公告)日：1998-10-15

申请号：DE69130160

申请日：1991-12-27

Applicant: NEC CORP

Inventor： EDA MASAHIRO

IPC: H04J14/00 ,  H04B10/27 ,  H04B10/275 ,  H04J14/02 ,  H04L12/423 ,  H04L12/433 ,  H04L12/64 ,  H04L12/28 ,  H04B10/00

Abstract: A supervisory node (2) and non-supervisory nodes (3 through 9) are connected in a loop by an optical transmission path (1). Over the loop (1) are transferred optical signals having wavelengths of lambda l through lambda n. An access right control packet 10 is transferred in the loop at the optical wavelength of lambda l. A node performing data transmission by line exchange writes its own node address (SA), the destination address (DA) and transmit reservation in the header of the access right control packet 10, and sends the packet out on the optical transmission path. The supervisory node 2 having received this access right control packet writes the wavelength to be used ( lambda i) into the used wavelength field (UWL), and notifies the transmit and receive nodes of the choice of the wavelength. The transmit node sends data to the receive node by line exchange at the designated wavelength lambda i.

公开(公告)号：JPH0758715A

公开(公告)日：1995-03-03

申请号：JP20419293

申请日：1993-08-18

Applicant: NEC CORP

Inventor： HIRAOKA TOSHIHIDE ,  EDA MASAHIRO

IPC: H04J3/00

Abstract: PURPOSE:To reduce the cost for system structuring, to shorten an incoming communication guard time, and to improve the efficiency of communication by automatically measuring the distance between an exchange and each subscriber and determining the incoming data transmission timing of each subscriber according to the measurement result. CONSTITUTION:At the start of the operation of an optical subscriber system or at the time of the relocation of a subscriber or new extension during the service operation for the optical subscriber system, a pulse signal shorter than the width of time slots assigned to respective subscribers 31-3n is sent from the exchange side to the time slots of the subscribers 31-3n. The subscribers 31-3n once receiving the pulse signal from the exchange 1 send the pulse signal back to the exchange 1 a specific time later, and the exchange 1 receives the pulse signal and detects phase differences from the pulse signal that the exchange has sent. The distances between the exchange 1 and subscribers 31-3n are calculated from the phase differences and incoming timing points corresponding to the subscribers 31-3n are calculated from the distances.

公开(公告)号：JPH06188878A

公开(公告)日：1994-07-08

申请号：JP34269992

申请日：1992-12-22

Applicant: NEC CORP

Inventor： EDA MASAHIRO

IPC: H04J14/08 ,  H04L9/14 ,  H04L9/18 ,  H04L9/36

Abstract: PURPOSE:To prevent data addressed to a present subscriber equipment from being easily intercepted by the other subscriber equipment in down-direction communication from a switchboard to the subscriber equipment. CONSTITUTION:The respective subscriber equipments 31 to 3L utilize up data and respectively transmit scramble selecting signals for selecting one of many key codes intrinsic to the present equipment to the switchboard 1. The switchboard 1 respectively scrambles the data of corresponding time slots by the key code corresponding to the respective transmitted scramble selecting signals and transmits them to the respective subscriber equipments 31 to 3L. The respective subscriber equipments 31 to 3L respectively descramble the received data by the key codes corresponding to the respective transmitted scramble selecting signals.

公开(公告)号：JPH0662025A

公开(公告)日：1994-03-04

申请号：JP21251592

申请日：1992-08-10

Applicant: NEC CORP

Inventor： EDA MASAHIRO

IPC: H04B10/27 ,  H04B10/038 ,  H04B10/07 ,  H04B10/275 ,  H04B10/29 ,  H04J14/02 ,  H04L12/433 ,  H04L12/42 ,  H04B10/20

Abstract: PURPOSE:To improve the system throughput of the multi-access system of a token passing system and to simplify address processing. CONSTITUTION:Normally, four token packets 5-8 rotate on a loop. A node 3 for which a transmission request is generated sets a first light wave length selection switch 10 so that the wave length lambda1 of a token corresponding to the node 1 of the transmission destination is pulled inside the node and the rotated token 5 is pulled inside the present node. Then, the output wave length of an E/O 14 provided with the light source of a variable wave length is set at the address wave length lambda5 of the transmission destination node 1 and a data packet 9 is transmitted from the second input terminal of the first light wave length selection switch 10 by the wave length lambda5 corresponding to the transmission destination node 1. After completing the transmission of the data packet 9, the output wave length of the light source of the variable wave length is switched to the token wave length lambda1 for the node 1 and the token packet 5 is transmitted.

公开(公告)号：JPH0472943A

公开(公告)日：1992-03-06

申请号：JP18423690

申请日：1990-07-13

Applicant: NEC CORP

Inventor： EDA MASAHIRO ,  FUJIWARA MASAHIKO

IPC: H04L12/42 ,  H04B10/07 ,  H04B10/2507 ,  H04B10/27 ,  H04B10/299 ,  H04L12/28 ,  H04L29/08

Abstract: PURPOSE:To reduce number of required high speed electric circuits by sending a header part and a data part through separate optical fiber transmission lines and quickening only the transmission speed for the data part when the transmission speed is increased to improve the throughput of the system. CONSTITUTION:A data part and a header part of a packet are sent through separate optical fiber transmission lines 13, 14 while being synchronously with each other timewise respectively. The header part sent through the 1st optical fiber transmission line 13 is converted into an electric signal by a 1st photoelectric converter 4, fed to an access processing circuit 10, in which the content of the header is read and when the packet is sent to its own node, after the content of the header part is cleared, the data is converted into an optical signal by the 1st photoelectric converter 4, the result is sent to a 1st optical fiber transmission line 13 and the data part is led to the 2nd photoelectric converter 6 from the 2nd optical fiber transmission line 14 and converted into an electric signal, it is fed to a data interface circuit 9.

公开(公告)号：JPH03244214A

公开(公告)日：1991-10-31

申请号：JP4144290

申请日：1990-02-22

Applicant: NEC CORP ,  NEC COMMUNICATION SYST

Inventor： EDA MASAHIRO ,  KOIKE ISAMU

IPC: H03K19/23

Abstract: PURPOSE:To add a majority condition by providing a decoder, which input is connected to the N pieces of input terminals, with N-bit input, the inver of M (M=2N) bit output, and an OR circuit to input all the output bits of the decoder and to output an OR condition signal to an output terminal corresponding to the combination of respective input bits so that more than the decided number of the N-bit inputs of the said decoder can obtain a logic value '1'. CONSTITUTION:An OR circuit 6 inputs the specified 11 outputs, out of 16 outputs OUT0-OUT15 of a decoder 5, and the outputs the OR condition signal to an output terminal 7. When more than two input terminals obtain the logic value '1' out of input terminals 1-4, any one of outputs OUT 3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15 of the decoder 5 obtains the logic value '1' and the logic value of the output terminal 7 is set to '1' by the OR circuit 6. When all the input terminals 1-4 obtain the logic value '1' or when only one of them obtains the logic value '1', the corresponding outputs 0, 1, 2, 4 and 8 of the decoder 5 are not inputted to the OR circuit 6 and therefore, the output terminal 7 maintains the logic value '0' as it is.

公开(公告)号：JPH10322316A

公开(公告)日：1998-12-04

申请号：JP7928698

申请日：1998-03-26

Applicant: NEC CORP

Inventor： EDA MASAHIRO ,  FUJIWARA MASAHIKO

IPC: H04J14/00 ,  H04B10/27 ,  H04B10/275 ,  H04J14/02 ,  H04L12/407 ,  H04L12/413 ,  H04L12/42 ,  H04B10/20

Abstract: PROBLEM TO BE SOLVED: To simplify an access processing circuit by previously allocating peculiar optical wavelengths to respective nodes as addresses, transmitting data with the transmission node, outputting only the specified wavelength to a second terminal in the reception node and receiving only the optical wavelength addressed to the reception node with a switch having a function outputting the optical wavelength except for the specified wavelength to a first output terminal. SOLUTION: A data interface circuit 5 recognizes the address optical wavelength of the node which is to transmit data and sends a control signal to a second electric-optic converter 15 having a variable wavelength light source and data is set to be transmitted with the optical wavelength. The control signal is transmitted to an optical filter 7 and the transmission optical wavelength of the optical filter 7 is set to the optical wavelength. When the optical wavelength exists in an arrived time slot, the signal is given to a control circuit 6 from a third optic-electric converter 13 through the optical filter 7. Thus, the control circuit 6 sends the control signal to the data interface circuit 5.

公开(公告)号：JPH06326723A

公开(公告)日：1994-11-25

申请号：JP11073493

申请日：1993-05-12

Applicant: NEC CORP

Inventor： EDA MASAHIRO ,  HIRAOKA TOSHIHIDE

IPC: H04J14/08 ,  H04B10/27 ,  H04B10/272 ,  H04L12/44 ,  H04B10/20

Abstract: PURPOSE:To reduce the system build-up cost, to decrease a guard time for incoming communication and to improve the efficiency of communication by deciding an incoming data transmission timing based on a result of distance measurement between an exchange station and each subscriber. CONSTITUTION:An exchange station 1 sends a pulse signal to each of subscribers 31-3n and each of the subscribers 31-3n sends back the pulse signal to the exchange station and a phase comparator 8 of the exchange station compares the phase of the pulse signal sent by itself with the phase of the received pulse signal to detect a phase difference. Then a counter 12 and a coding circuit 11 calculate the distance between the exchange station and each subscriber based on the phase difference and to calculate a transmission timing of a corresponding incoming signal. In the case of usual data communication, the exchange station utilizes outgoing communication to send the transmission timing information to each subscriber and each subscriber sends incoming data for the exchange station based on the transmission timing information.

公开(公告)号：JPH0514284A

公开(公告)日：1993-01-22

申请号：JP18332391

申请日：1991-06-27

Applicant: NEC CORP

Inventor： EDA MASAHIRO

IPC: H04J14/00 ,  H04B10/27 ,  H04B10/275 ,  H04B10/278 ,  H04B10/291 ,  H04J14/02 ,  H04L12/40 ,  H04L12/407 ,  H04L12/42 ,  H04L12/43

Abstract: PURPOSE:To simplify the node constitution and to facilitate the access processing by sending the data with the light wavelength corresponding to the receiving node into the time slot in which the node only can transmit the data, by the transmitting node. CONSTITUTION:Into a time slot partitioned by a frame pulse 2, a data packet 3 of the fixed length sent by plural different light wavelengths is transmitted. The inherent light wavelength is assigned as an address for each node 1 beforehand. The transmitting node is the light wavelength corresponding to the receiving node, and sends it into the time slot assigned to the transmitting node or the light wavelength outputted by the transmitting node. The receiving node receives only the light wavelength of the receiving node destination by a light wavelength selecting switch and passes the light wavelength except it in the condition of the light signal. Thus, by the small number of the electric-light converter and the light-electric converter, the nodes 1 is constituted. An access processing circuit in the nodes 1 becomes facilitated.