Digital Demodulator for Wide Bandwidth SAR
نویسندگان
چکیده
A novel approach to the design of efficient digital quadrature demodulators for wide bandwidth SAR systems is described. Efficiency is obtained by setting the intermediate frequency to 1/4 the ADC sampling frequency. One channel is made filterfree by synchronizing the local oscillator with the output decimator. The filter required by the other channel is optimized through global search using the system level performance metr i c ~ integrated sidelobe level ratio (ISLR) and peak sidelobe level ratio (PSLR).
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