| 摘要 |
A method of remotely sensing of the state (i.e. the amplitude and frequency of the waves) of a selected zone (Z) of a body of water comprises: transmitting successive radar pulses ( DELTA ); receiving corresponding echoes ( beta ) returned by the waves of the selected zone; forming series of samples of said echoes ( beta ), each series having a different time shift ( delta 1, delta 2, delta 3) and corresponding to a different sector of the selected zone; keeping one of these series, corresponding to a reference sector, unchanged; applying to the other series correction factors for eliminating therefrom the influence of the difference in distance and/or azimuth, with respect to the transmission point, between the sectors corresponding to the series in question and the reference sector; and summing the so-corrected series or the corresponding frequency spectra with that corresponding to the reference sector, thereby improving the signal-to-noise ratio of the signals emanating from the reference sector, which are representative of the state of the selected zone. <IMAGE> |
