Feature extraction of rotating target based on bistatic micro-Doppler analysis

Efficient Estimation of the Helicopter Blade Parameter by Independent Component Analysis

“…The proposed method uses the method proposed in [13] because it provides an analytic solution for l, , and various geometrical parameters by using a combination of monostatic and bistatic observations. The analysis considers a point scatterer P located at a distance l from the origin O and rotating at  around the z axis, i.e., on the x-y plane, that is illuminated by radar T from a distance RT(t) at time t (Fig.…”

“…1). The estimated amplitude, angular velocity, and initial phase of (4) -(5) by ˆ( , , ) TT l  and ˆ( , , ) BB l  respectively, can be found by analyzing the time-varying MD radar of the signals received at the radars T and R. ˆ( , ) RR l  can be calculated by using the following relationship [13]:…”

“…Physical optics (PO) was applied to obtain the complex reflected radar signal at frequency 10-GHz with a PRF = 8 kHz. s(t) was obtained by positioning the received signal at the corresponding time delay; elements in A in (13) were chosen randomly from a uniform distribution from 0.5 and 1.…”

“…Another method [13] assumes an ideal point scatterer and successfully estimates l, , and monostatic/bistatic angles by using the Hough transform cube (HTC) of the TF image of signals obtained from monostatic and bistatic measurement scenarios. However, this method is based on the assumption that the isotropic scatterer is perfectly separated and detected in HTC, so this method can yield a poor result when peaks in the Hough transform of the TF image are obscured by blade flashes.…”

“…In addition, the proposed method does not require any complicated tomographic imaging, and prevents errors caused by the limited resolution of the Radon transform [10 -12]. Furthermore, the proposed method utilizes the separated signal of each blade, and therefore can prevent enormous error caused by using the unseparated signal [13]. In simulations using the radar signal of a blade estimated by the method of physical optics (PO), the proposed method accurately estimated the blade parameters.…”