Abstract: A method and system for estimating a time shift required for symbol synchronization in a block oriented digital communication systems such as an orthogonal frequency division multiplexing (OFDM) or a discrete multi-tone (DMT) data transmission system. The method uses an N/d inverse discrete Fourier transform (IDFT), where N is a sample number and d is a decimation factor, or alternatively an N/(2d) inverse fast Fourier transform (IFFT) for a real received signal or an N/d IDFT for a complex received signal.

Abstract: A method and apparatus for detecting a channel jammed by narrowband jamming interference in a block oriented digital transmission system such as an orthogonal frequency division multiplexing (OFDM) or discrete multi-tone (DMT) system. A spectrum of a received data bearing signal is examined to identify areas of the spectrum that are likely corrupted by a narrowband jamming interference. The method identifies jammed channels by applying a boxcar filter, in order to identify narrow peaks in the spectrum that are substantially larger in magnitude than adjacent channels. Channels identified as jammed or affected by a jamming signal, are listed in a jam mask used for screening out corrupted channels during data transmission.

Abstract: A method and system for estimating a time shift required for symbol synchronization in a block oriented digital communication systems such as an orthogonal frequency division multiplexing (OFDM) or a discrete multi-tone (DMT) data transmission system. The method uses an N/d inverse discrete Fourier transform (IDFT), where N is a sample number and d is a decimation factor, or alternatively an N/(2d) inverse fast Fourier transform (IFFT) for a real received signal or an N/d IDFT for a complex received signal.

Abstract: A method and apparatus for detecting a channel jammed by narrowband jamming interference in a block oriented digital transmission system such as an orthogonal frequency division multiplexing (OFDM) or discrete multi-tone (DMT) system. A spectrum of a received data bearing signal is examined to identify areas of the spectrum that are likely corrupted by a narrowband jamming interference. The method identifies jammed channels by applying a boxcar filter, in order to identify narrow peaks in the spectrum that are substantially larger in magnitude than adjacent channels. Channels identified as jammed or affected by a jamming signal, are listed in a jam mask used for screening out corrupted channels during data transmission.

Abstract: A method and system for estimating a time shift required for symbol synchronization in a block oriented digital communication systems such as an orthogonal frequency division multiplexing (OFDM) or a discrete multi-tone (DMT) data transmission system. The method uses an N/d inverse discrete Fourier transform (IDFT), where N is a sample number and d is a decimation factor, or alternatively an N/(2d) inverse fast Fourier transform (IFFT) for a real received signal or an N/d IDFT for a complex received signal.