Diverse Frequency Time-Modulation for Passive False Target Spoofing:
Design and Experiment
Abstract
This paper presents a new design of diverse frequency time-modulation
for linear frequency modulated (LFM) radar passive false target
spoofing. To realize the passive diverse frequency time-modulation, the
modulated metasurface is designed accordingly, which is composed by a
set of elements, each of which is independently time-modulated to
realize specific false targets in the high-resolution range profile
(HRRP) of the radar system. Thanks to the control of the modulation
scheme in each element and the combined response of the overall surface,
we demonstrate the capability to realize several false target patterns
consisting of single and multiple targets symmetrically, or
asymmetrically, distributed around the actual target. A HRRP general
expression of the time modulated diverse frequency metasurface at
different observation angles is given to show the relation between the
generated false targets and frequency components. Since having more
flexible capacity of reflected signal manipulation comparing to false
target spoofing only through time modulation with consistent modulation
frequency, the proposed method has enhanced performance on control of
false targets at different observation angles. Both simulated and
measured results demonstrate the validity of false targets manipulation,
demonstrating its effectiveness as electromagnetic countermeasure for
achieving radar camouflaging and deception.