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Analysis of Phase-Dependent RCS Measurements



Lorant A. Muth, Timothy Conn


Free space coherent radar cross section measurements on a moving target will trace a circle centered on the origin of the complex (I,Q) plane. Noise will introduce only small random variations in the radius of the circle. In real measurement configurations additional signals are present due to background, clutter, target-mount interaction, instrumentation and the average of the time-dependent system drift. Such signals are all important contributors to the uncertainty in radar cross section measurements. These time-independent complex signals will translate the origin of the circle to a complex pint (I0, Q0). Such data is then defined by the 3 parameters (I0, Q0), the center of the circle, and the radar cross section of the target. We analyze data obtained when a target is moved relative to the pylon into a phase-dependent and a phase-independent part using the techniques of (1) three parameter numerical optimization, (2) least median square fit, (3) adaptive forward-backward FIR procedure, and (4) orthogonal distance regression technique applied to a circle. We determine the three parameters under consideration with known and acceptable uncertainties. However, the contribution of systematic errors due to unwanted in-phase electric signals must still be carefully evaluated.
Conference Dates
November 4-8, 2002
Conference Location
Cleveland, OH, USA
Conference Title
Antenna Measurement Techniques Association


background, clutter, coherent RCS measurements, measured RCS amplitude, measured RCS phase, radar cross section, RCS, RCS uncertainty


Muth, L. and Conn, T. (2002), Analysis of Phase-Dependent RCS Measurements, Antenna Measurement Techniques Association, Cleveland, OH, USA (Accessed April 21, 2024)
Created November 7, 2002, Updated October 12, 2021