| 摘要 |
A FM-CW radar system comprises a frequency modulated continuous wave digital generator that produces both in- phase (I) and quadrature-phase (Q) outputs to orthogonally oriented transmitter antennas. A linearly polarized beam is output from a switched antenna array that allows a variety of I-and-Q pairs of bowtie antennas to be alternately connected to the transmitter and receiver. The receiver inputs I-and-Q signals from another bowtie antenna in the array and mixes these with samples from the transmitter. Such synchronous detectio n produces I-and-Q beat frequency products that are sampled by dual analog-to- digital converters (ADC's). The digital samples receive four kinds of compensation, including f requency-and-phase, wiring delay, and fast Fourier transform (FFT) . The compensated samples are then digitally converted by an FFT- unit into time-domain signals. Such can then be processed conventionall y for range information to the target that has returned the FM-CW echo signal.
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