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

Claim 3:
4. The signal processing apparatus according to claim 1, further comprising:
secondary topographic echo presence determination circuitry to determine whether the secondary topographic echo is present based on electric power of the secondary topographic echo calculated by the secondary topographic echo processor; and
primary topographic echo presence determination circuitry to determine whether the primary topographic echo is present based on electric power of the primary topographic echo calculated by the primary topographic echo processor, wherein
when the secondary topographic echo presence determination circuitry determines the secondary topographic echo as being absent, the secondary echo processor (i) sets electric power of the topographic-echo-unprocessed secondary echo estimated from the reception signal in the secondary echo region as electric power of the topographic-echo-processed secondary echo and (ii) estimates the spectral width of the topographic-echo-unprocessed secondary echo and the Doppler velocity of the topographic-echo-unprocessed secondary echo as the spectral width of the topographic-echo-processed secondary echo and the Doppler velocity of the topographic-echo-processed secondary echo, respectively,
when the primary topographic echo presence determination circuitry determines the primary topographic echo as being absent, the primary echo processor (i) sets electric power of the topographic-echo-unprocessed primary echo estimated from the reception signal in the primary echo region as electric power of the topographic-echo-processed primary echo and (ii) estimates the spectral width of the topographic-echo-unprocessed primary echo and the Doppler velocity of the topographic-echo-unprocessed primary echo as the spectral width of the topographic-echo-processed primary echo and the Doppler velocity of the topographic-echo-processed primary echo, respectively,
when an echo determined as the weak echo by the strong-and-weak-echo distinction and output circuitry is the secondary echo and when the secondary topographic echo presence determination circuitry determines the secondary topographic echo as being absent, or
when an echo determined as the weak echo by the strong-and-weak-echo distinction and output circuitry is the primary echo and when the primary topographic echo presence determination circuitry determines the primary topographic echo as being absent,
the weak echo strength correction circuitry sets electric power estimated by the weak echo processor as electric power of the weak echo,

in addition, when an echo determined as the strong echo by the strong-and-weak-echo distinction and output circuitry is determined by the secondary topographic echo presence determination circuitry or the primary topographic echo presence determination circuitry as being free from the secondary topographic echo or the primary topographic echo,
the strong-and-weak-echo distinction and output circuitry provides as the weak echo parameter, the reception signal of the secondary echo or the primary echo determined as the weak echo instead of the strong-topographic-echo-removed reception signal, and
the strong echo remover generates a reception signal resulting from removal of a frequency component of the strong echo from the reception signal of the secondary echo or the primary echo determined as the weak echo that represents the weak echo parameter.