Patent ID: 6563896
Filing Date: 2003-05-13
Classification: H04L

Abstract:
A digital broadcast receiver for receiving a digital signal transmitted in one of a plurality of transmission modes having different respective symbol time lengths and in which each symbol includes two signal intervals with equal periods, comprising:a delay circuit for delaying a received digital signal by a prescribed period; a correlation circuit for correlating a delay output of the delay circuit with the received digital signal; a moving average circuit for calculating a moving average of a correlation output of the correlation circuit over a period that is equal to the period of the two signal intervals; selecting means for selecting at least one assumed transmission mode from the plurality of transmission modes chosen in a predetermined order; setting means for setting a delay time of the delay circuit to a time corresponding to the symbol time length of each selected transmission mode; counting means for counting, for each assumed transmission mode, the number of times an output of the moving average circuit exceeds a predetermined value; and judging means for judging, based on counting results of the counting means, that a transmission mode that gives a maximum number of times that the output of the moving average circuit exceeds the predetermined value is an actual transmission mode of said plurality of transmission modes.