Title:
DIGITAL BROADCAST RECEIVER WITH TRANSMISSION MODE IDENTIFICATION FUNCTION
Document Type and Number:
Japanese Patent JP3503723
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To surely attain automatic identification of a transmission mode by delaying a base band signal by different delay times depending on a plurality of transmission modes and calculating a correlation between the base band signal and each delay output signal.
SOLUTION: Correlation detection circuits 21-24 of an identification section corresponding to transmission modes respectively provide a high level as a correlation value in the case of receiving a broadcast wave of a concerned mode. Delay elements 21A-24A delay the base band signal by delay times T1-T4 equivalent to a valid symbol length in the corresponding transmission mode. I, Q signals are fed to one input of multipliers 21B-24B and delay output signals are fed to the other input. Both the input signals are multiplied and fed to integration devices 21C-24C and their output signals are fed to a comparator circuit 25. The circuit 25 detects maximum values of output correlation values of the circuits 21-24 and compares and discriminates whether or not the maximum value is a prescribed level or over and provides an output of an identification signal denoting the transmission mode at which the maximum value is obtained when the maximum value is the prescribed level or over.
Inventors:
Kazushi Tahara
Application Number:
JP12370896A
Publication Date:
March 08, 2004
Filing Date:
May 17, 1996
Export Citation:
Assignee:
Pioneer Corporation
International Classes:
H04L27/22; H04B1/06; H04J4/00; H04J11/00; (IPC1-7): H04L27/22; H04B1/06; H04J4/00
Domestic Patent References:
| JP7143097A | ||||
| JP8125630A | ||||
| JP8125631A | ||||
| JP8265291A | ||||
| JP9214465A |
Attorney, Agent or Firm:
Motohiko Fujimura