Obtaining transfer function of radio signals without knowledge of transmitted signals e.g. for car radio, by selecting correct coefficients for non-recursive filters to evaluate target function

摘要

When two signals having different transfer functions and substantially the same modulation content arrive at a receiver, a target function is evaluated based on the selection of correct coefficients for one filter applied to the first signal and another filter applied to the second signal, resulting in two substantially equal signals. The filters are non-recursive filters with adaptive coefficients determined when the target function is evaluated. Independent claims are also included for the following: (1) a method of obtaining the transfer function of radio signals; (2) a method of determining channel parameters (3) a method of determining a multipath countering filter (4) a method of normalizing the values of the filter coefficients (5) a method of selecting the mu terms, coefficients, lines or columns (6) a method of approximately determining the weighting of the signal components (7) a method of countering multipath reception (8) a circuit for countering multipath reception (9) a telecommunications terminal; and (10) a car radio.