Patent ID: 11874408
Assignee: NEC CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 2:
3. The sonar apparatus according to claim 1, wherein the one or more signal waveforms comprise two signal waveforms, the correlation value is a cross-correlation value between the two signal waveforms, the signal received by the acoustic array is a pulse signal modulated by Linear Frequency Modulation (LFM), and
wherein the processor, when executing the program instructions stored in the memory:
calculates a Doppler coefficient, based on a peak value Rμμ(0) of an autocorrelation Rμμ(τ) of the cross-correlation value, a peak value Raa(0) of an autocorrelation Raa(τ) of the autocorrelation Rμμ(τ), and an absolute value of a frequency change rate and a pulse length to derive the target velocity.