Patent ID: 11927666
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  Y | IPC G

Claim 9:
10. A signal processing method of deriving a spectral parameter of a weak echo from electric power, a spectral width, and a Doppler velocity of a topographic-echo-processed echo resulting from removal of a topographic echo in a secondary echo as well as electric power, a spectral width, and a Doppler velocity of a topographic-echo-processed echo resulting from removal of a topographic echo in a primary echo, the electric power, the spectral widths, and the Doppler velocities being found from a reception signal of a reflected wave of pulsed undulation repeatedly transmitted into a space, the signal processing method comprising:
a determination step of comparing a topographic-echo-processed secondary echo and a topographic-echo-processed primary echo with each other and making categorization into a strong echo and the weak echo;
a weak echo parameter determination step of setting as weak echo parameters, (i) a strong-topographic-echo-removed reception signal resulting from removal of the topographic echo in the primary echo or the secondary echo determined as the strong echo in the determination step and (ii) electric power of a topographic echo in the secondary echo or the primary echo determined as the weak echo; and
a spectral parameter output step of providing as spectral parameters of the weak echo, (i) electric power of the weak echo estimated from a reception signal in a weak echo region resulting from phase correction of a reception signal resulting from removal of a frequency component of the strong echo from the strong-topographic-echo-removed reception signal representing the weak echo parameter, (ii) a spectral width of the weak echo representing the weak echo parameter, and (iii) a Doppler velocity of the weak echo, wherein
the spectral parameter output step includes providing as spectral parameters of the weak echo, electric power of the weak echo obtained by correcting electric power of the weak echo estimated from the reception signal in the weak echo region with electric power of the topographic echo representing the weak echo parameter in a weak echo strength correction step.