Estimation appts. to estimate coefficients of adaptive filter to emulate transmission characteristics of known signal

摘要

The appts. estimates filter coefficients for a filter which outputs a signal with a response corresponding to the signal transmission characteristics of a known signal and the response to it, which are sent to a signal transmission system (100) of unknown characteristics. A product sum calculating device accumulates, over a predetermined period, the product of the difference between the response of the signal transmission system (100) and the filter response, and the signal sent to the transmission system (100). A square sum calculating device accumulates, over a predetermined period, the sum of the squares of the signal sent to the transmission system (100). An update quantity calculating device (230) calculates the filter coefficient update values from the results of the results of the sum of the products and the sum of the squares. The derived filter coefficient update values are used to update the filter coefficients.