METHOD AND APPARATUS FOR A FAST LINEAR FREQUENCY MODULATION TARGET DETECTION COMPENSATING DOPPLER EFFECT ACCORDING TO THE TARGET SPEED

摘要

The present invention relates to a broadband sonar system. To be more specific, the present invention relates to a fast linear frequency modulation (LFM) target detection system providing a correlation-based broadband LFM alignment summation filter, which aligns and totals results of each correlator in which a shift in frequency and a change in sweep rate resulted from the Doppler Effect are reflected, and the method for the same. The fast LFM target detection method compensating the Doppler Effect with respect to the speed of the target in the sonar system consisting of a number of correlators and correlation-based alignment summation filters includes the steps of: transmitting a LFM transmitting signal to the target; receiving a broadband LFM reception signal at the target speed of the target; calculating a reference filter of each correlator by using the LFM transmitting signal; reflecting the shift in frequency, which indicates the Doppler Effect caused in respect to the target speed, and the change in sweep rate into the reference filter; reflecting a time delay into the correlation results of each correlator; and aligning and totaling the correlation results in which the time delay is reflected in order to generate one correlation-based alignment summation filter.