Fujitsu Corporation

Katsuaki Yamanaka

Satoshi Maeda

Yasuhiro Yamauchi

Shigeo Tani

Yoshimi Toyoda

Naoto Kawashima

Hirokazu Shimada

Toshiaki Kinoshita

Yuki Iwamasa

Hironori Aono

Chie Eiza

Yoshinori Hiraike

A Radio Equipment Controller connected, via a plurality of transmission paths, to a plurality of pieces of Radio Equipment for performing communication with a mobile station, and also connected to an upper-level device is provided. The Radio Equipment Controller includes a required time measurement portion that measures, for each piece of Radio Equipment, required time for the Radio Equipment and the Radio Equipment Controller to relay data that has a predetermined size and is transmitted and received between the upper-level device and the mobile station, and a relaying portion that relays target data that is data to be transmitted and received between the upper-level device and the mobile station by delaying a time to transmit the target data based on the required time for the Radio Equipment relaying the target data.

Radio equipment controller, base transceiver station, and method for relaying data

A monitoring system of the present invention achieves highly reliable switching control by having a monitored response time creating/calculating unit calculate a maximum value and a minimum value between which a response time is judged as normal from a response time of the last measurement and from a response time of the last but one measurement, and by having a monitored response time comparing unit set a range in which a response time is judged as normal in a manner that agrees with past response times.

Monitoring system

A digital communication system includes a first station, a second station and a network therebetween. The first station includes a clock selecting device for selecting one clock from a plurality of different clocks; and a transmitting device for transmitting frames to the second station based on the selected clock. The second station includes an evaluating device for evaluating transmission quality of data in each of the frames received from the first station; and a quality message inserting device for inserting the evaluated transmission quality as a quality message into a part of the corresponding frame to be transmitted to the first station. The first station further includes a message processing device for extracting the quality message from each received frame to convert the extracted quality message into a corresponding message signal to output the message signal; and a control device for causing the clock selecting device to select a clock corresponding to the message signal output from the message processing device.

Digital communication system

Growing community of inventors

Osaka, Japan

Katsuaki Yamanaka