公开(公告)号：JP2003134024A

公开(公告)日：2003-05-09

申请号：JP2001330846

申请日：2001-10-29

Applicant: ATR ADVANCED TELECOMM RES INST

Inventor： CHO HEI ,  HASUIKE KAZUO

IPC: H04B7/26 ,  H04W28/04 ,  H04W28/10

Abstract: PROBLEM TO BE SOLVED: To provide a communication system in which information can be rightly transmitted even when a radio wave environment is changed. SOLUTION: A communication system 100 is provided with a communication device 10, a base station 20, portable terminal equipment 30, a cable line 40, and a radio channel 50. When transmitting a plurality of packets to the portable terminal equipment 30, the communication device 10 detects the occurrence of the transmitting loss of packets on the radio channel 50 on the basis of a signal-to-noise ratio, which is the index of the radio wave environment of the radio channel 50. Besides, when the transmitting loss of packets on the radio channel 50 is detected, the communication device 10 decreases the number of packets to be simultaneously transmitted by half and with that decreased number as a reference, the number of packets to be simultaneously transmitted is increased.

公开(公告)号：JP2003258811A

公开(公告)日：2003-09-12

申请号：JP2002055471

申请日：2002-03-01

Applicant: ATR ADVANCED TELECOMM RES INST

Inventor： UEDA TETSUO ,  SOMPRAKASH BANDYOPADHYAY ,  HASUIKE KAZUO

IPC: H04L12/28 ,  H04L12/733 ,  H04W16/28 ,  H04W40/02 ,  H04W40/12 ,  H04L12/56 ,  H04Q7/22 ,  H04Q7/24 ,  H04Q7/26 ,  H04Q7/30

Abstract: PROBLEM TO BE SOLVED: To transmit message data even when the opposite station is off-line and to provide a service when a self-station intends to be off-line in a radio network such as an ad hoc radio network. SOLUTION: When its own station intends to be off-line, the self-station selects a proxy radio station to be a proxy for the self-station from an MGLS table on the basis of a prescribed criteria (S142), and transmits to the proxy radio station a proxy request signal for requesting the proxy radio station to be a proxy for the self-station (S145). When the self-station receives a proxy request signal to the self-station, the self-station inserts proxy information showing that the self-station is a proxy radio station for a particular different ratio station in the MGLS table to update the MGLS table, and also updates the MGLS table of the different radio station by transmitting a prescribed packet signal with the proxy information included in transmitting the packet signal to the different radio station. COPYRIGHT: (C)2003,JPO

公开(公告)号：JP2003233612A

公开(公告)日：2003-08-22

申请号：JP2002033072

申请日：2002-02-08

Applicant: ATR ADVANCED TELECOMM RES INST

Inventor： KURABAYASHI NORIYUKI ,  YAMAZAKI TATSUYA ,  YUASA TAICHI ,  HASUIKE KAZUO

IPC: G06F17/30 ,  G06F13/00

Abstract: PROBLEM TO BE SOLVED: To develop communication of a high degree of freedom by enabling a user to acquire a variety of information from another user computer. SOLUTION: A communication system 10 includes a server 12. In a chat room provided by the server 12, a first to a fourth user of user computers 18 to 24 connected to the server 12 via the Internet 16 can chat. If, for example, the first user is silent on a subject, the user computer 18 requests information support from the server 12. The server 12 responsively mediates the information support request to the other user computers 20 to 24. Any one of the user computers 20 to 24 capable of information support provides information interesting the user computer 18. COPYRIGHT: (C)2003,JPO

公开(公告)号：JP2003115858A

公开(公告)日：2003-04-18

申请号：JP2001307658

申请日：2001-10-03

Applicant: ATR ADVANCED TELECOMM RES INST

Inventor： MASAYAMA KAZUNARI ,  SOMPRAKASH BANDYOPADHYAY ,  UEDA TETSUO ,  HASUIKE KAZUO

IPC: H04L12/46 ,  H04L12/28 ,  H04W16/28 ,  H04W40/16 ,  H04W84/18 ,  H04W88/02 ,  H04Q7/38

Abstract: PROBLEM TO BE SOLVED: To perform stable radio communication while securing a stable route by efficiently updating a routing table even when a radio station frequently moves. SOLUTION: In the wireless network for performing packet communication among respective radio stations, on the basis of a signal from an adjacent radio station containing the measured value of a signal-to-interference-noise ratio (SINR) when each of adjacent radio station receives a signal from a present station, the SINR watched from each of adjacent radio station for each azimuth in a horizontal plane with the present station as a center is found, the maximum SINR is selected for each adjacent radio station and defined as a degree of affinity, an adjacent link state table containing the relevant degree of affinity is generated, and an updating signal containing this table is transmitted and exchanged with each of other radio stations so that a global link state table containing the information of the adjacent link state table for each of relevant radio stations can be saved. On the basis of the global link state table, the route from a transmitting source radio station to a destination radio station is selected and a packet signal is routed.

公开(公告)号：JP2003115851A

公开(公告)日：2003-04-18

申请号：JP2001307644

申请日：2001-10-03

Applicant: ATR ADVANCED TELECOMM RES INST

Inventor： HORISAWA SHINGO ,  SOMPRAKASH BANDYOPADHYAY ,  UEDA TETSUO ,  HASUIKE KAZUO

IPC: H04L12/28 ,  H04B7/26 ,  H04W84/18 ,  H04W88/02 ,  H04Q7/36

Abstract: PROBLEM TO BE SOLVED: To suppress interference of the same channel on a wireless network, to increase a number of simultaneous communications in comparison with the conventional case and to increase a communication information quantity. SOLUTION: In the wireless network for performing packet communication between respective radio stations, on the basis of a signal from the adjacent radio station containing the measured value of a signal-to-interference-noise radio (SINR) when each of adjacent radio station receives a signal from the present station, the SINR watched from each of adjacent radio station for each azimuth within a horizontal plane with the present station as a center is found, the maximum SINR is selected for each adjacent radio station and defines it as a degree of affinity with each adjacent radio station, an adjacent link state table containing the relevant degree of affinity and the azimuth corresponding thereto is generated and on the basis of this table, radio communication is performed with the adjacent radio station of an opposite party. Besides, an under-communication table containing an azimuth for each adjacent radio station under radio communication with the other radio station is generated and on the basis of this table, a radio signal is transmitted by using an exclusive radiation pattern for turning a null point to the azimuth of the adjacent radio station under radio communication with the other radio station.