MOVING DIRECTION MEASURING DEVICE AND TRACKING APPARATUS

A moving direction measuring device includes a collation Fourier pattern data generating section, a registration Fourier pattern data generating section, a pattern processing section, and a moving direction measuring section. The collation Fourier pattern data generating section generates collation Fourier two-dimensional pattern data by performing two-dimensional discrete Fourier transform for two-dimensional pattern data input at time T.sub.n. The registration Fourier pattern data generating section generates registration Fourier two-dimensional pattern data by performing two-dimensional discrete Fourier transform for two-dimensional pattern data input at time T.sub.n+1. The pattern processing section synthesizes these Fourier two-dimensional pattern data, and performs either two-dimensional discrete Fourier transform or two-dimensional discrete inverse Fourier transform for the resultant data. The moving direction measuring section obtains a correlation peak in a correlation component area appearing in the synthesized Fourier two-dimensional pattern data having undergone Fourier transform performed by the pattern processing section, and obtains a direction from a reference position in the correlation component area to a position of the correlation peak as a moving direction of the device.