Ground-based radar interferometer for tracking fast approaching targets

This study describes the design and initial evaluation of a radar that detects and tracks a fast approaching target in a short-range application. In some radar applications, tracking durations less than 1 s and 3D tracking accuracy of a few tens of centimetres are required. To satisfy these requirements, a radar interferometer is proposed to simultaneously detect and track a target. A frequency-modulated continuous wave (FMCW) waveform is chosen and a method of separating clutter from a valid signal is developed to obtain very precise range information. In the tracking algorithm, a least squares (LS) filter is adopted because of its fast computing speed and good convergence characteristics to a steady state. This system is constructed using an open architecture approach, with a direct digital synthesiser, a field programmable gate array (FPGA) and a digital signal processor (DSP) as core components. The radar system was evaluated through real field testing. The test results showed that the proposed radar and tracking methods are able to estimate very accurate target positions in real field testing.