公开(公告)号：JP2003115894A

公开(公告)日：2003-04-18

申请号：JP2002157227

申请日：2002-05-30

Applicant: IBM

Inventor： AMES STEPHEN JOHN ,  BALL ROY KEARNS ,  SCHOW CLINT LEE ,  WHITE CHRISTOPHER KEITH

IPC: H04B10/00 ,  H04B10/04 ,  H04B10/06 ,  H04B10/14 ,  H04B10/158 ,  H04B10/26 ,  H04B10/43 ,  H04L29/08 ,  H04B10/28

Abstract: PROBLEM TO BE SOLVED: To provide a low-cost, easily packaged and fully self-contained data rate detector and a method of data rate autodetection that allows selection of the data rate of an incoming data signal without an external control signal or complicated clock recovery system. SOLUTION: A data receiver, which can be an optical transmitter/receiver, a modem and a router hub can detect the transmission rate of incoming data. The data are converted to electrical waves suited to passive or active band pass filtering. A frequency at which the wave is filtered is determined from a plurality of known possible transmission rates and selected as a frequency having the most detectable difference in the power spectrums. By packaging the filter at a correspondent frequency, data having that (those) frequency(ies) are transmitted. Next, a signal detector receives a signal transmitted through the filter and a corresponding data rate can be determined. Further, a plurality of frequencies can be filtered by using the stages of filters and signal detectors corresponding to different frequencies or by filters and detectors capable of operation in a plurality of frequencies.