Research

Motion parameters estimation of a moving target based on instantaneous frequency estimates using a passive acoustic sensor

 2022.11.3.

The respected Comrade Kim Jong Un said:

"By spurring the building of a sci-tech power, we should achieve a new leap forward in rapidly developing the country's science and technology and usher in an era of prosperity by means of science, thus bringing about a revolutionary turn in socialist construction."

To estimate motion parameters (MPs) using the instantaneous frequency (IF) estimates of an acoustical target received from passive acoustic sensors allows less management cost and less danger of detection in monitoring system.

MPs is representated as {V, D, f0, tc}. Here V is the target's travel speed, D is the closest point of approach slant range, f0 is the source acoustical frequency, and tc is the time of travel from the closest point of approach to the sensor.

We proposed a method for estimating the MPs from IF estimates of moving target received by an acoustic sensor placed on the ground and compared and evaluated with prior methods through simulations.

We denoted t1, t2, …, tN for the measured IFs at uniform intervals of time △T and derived a novel formulation between the IF and MPs. So the estimation problem of the MPs can be reduced as a quadratic optimization problem of T = tN-tc and s = D(C2-V2)0.5/V/C.

And we applied the polynomial Wigner-Ville distribution (PWVD) to the IF estination of sound emitted from the air. Especially we proposed a method for determining the optimal window width for an adaptive IF estimation which is appropriate with the Doppler Effect.

Experimental results show that the mean-square error (MSE) of estimates obtained by the proposed method is smaller than ones of the prior methods.

Our results of this study were published in the journal "Journal of Circuits, Systems, and Computers" (Vol.30, No.14, 2021, 2150264) of the World Scientific Publishing Company under the title of "Motion Parameters Estimation of a Moving Target Based on Instantaneous Frequency Estimates Using a Passive Acoustic Sensor" (https://doi.org/10.1142/S0218126621502649).