Patent Document ID: 20060239385
Application ID: 10541850
Patent Flag: 0

Claim One:
1. A method for identifying obstacles in a transmission channel by means of propagation-delay measurement through analysis of the channel impulse response (I k (n)) of the transmission channel using a time-discrete adaptive equalizer connected in series to the transmission channel, comprising: determining IIR filter coefficients (a n ) of a recursive filter portion of the timer discrete adaptive equalizer and FIR filter coefficients (b n ) of a non-recursive filter portion of the time-discrete adaptive, equalizer; assigning a first input vector (A(n)) pre-assigned with zeros with index-corresponding IIR filter coefficients (a n ) and a second input vector (B(n)) pre-assigned with zeros with index-corresponding FIR filter coefficients (b n ), wherein the first vector element (A( 0 )) of the first input vector (A(n)) is defined with the value 1; determining a first output vector (A′(n)) from the first input vector (A(n)) and of a second output vector (B′(n)) from the second input vector (B(n)) using a discrete Fourier transformation; forming a discrete channel transmission function (H k (n)) by dividing the first output vector (A′(n)) by the second output vector (B′(n)); determining a discrete channel impulse response (I k (n)) from the discrete channel transmission function (H k (n)) using an inverse discrete Fourier transformation; determining a local maxima of the channel impulse response (I k (n)) according to location in time; and converting the locations in time of the local maxima into corresponding distances of obstacles relative to a position of a measurement receiver containing the time-discrete adaptive equalizer by multiplication by the transmission rate.