Patent ID: 6317473
Filing Date: 2001-11-13
Classification: H04L,H04N

Abstract:
An apparatus for demodulating digital broadcast signals comprising data modulated on a multiplicity of spaced carrier frequencies, comprising:analog-to-digital conversion means for providing a series of digital samples of the broadcast signal;real-to-complex conversion means for converting each digital sample to a complex number value;Fourier Transform means for analyzing the complex number values to provide a series of data signal values in complex number format for each carrier frequency; andsignal processing means for processing the series of data signal values including phase error correcting means;said phase error correcting means including means for converting the data signal values from a complex number format to a phase angle format, means for determining a common phase error by assessing the phase of continual pilot signals in the broadcast signals and determining the variation in phase of the continual pilot signals between consecutive symbols in the broadcast signals, and means for subtracting the common phase error from the data signal values.