I OFFER TO CONSIDER DIRECT CONVERSION RECEIVES ON COMPARISON FOLLOWING SHEMES FROM ANALOG DEVICES
AD9262,AD0269
IN RECEIVERS, WITH AD9262,AD9269 ,APPLY QEC (QUADRATURE ERROR CORRECTION) ,I THINK QEC NO GUARATEE FULLY CORRECTION GAIN AND PHASE ERRORS TYPICAL FOR I/Q PROCRSSING SIGNAL.IN THE MIXER GENERATING
UNWANTED DC OFFSETS FROM LO LEAKS TO RF.
IN RECEIVERS, WHERE APPLY ADCs WITH FUNCTION AMPLITUDE DETECTOR ,THESE PROBLEMS FULLY BE ABSENT.
NOW ANALYSE SAMPLE RATE IN CONVERTERS.
AD9262 HAVE 30-160MSPS FOR SELECTABLE BANDWITH 5/10/20MHz complex
AD9269 HAVE 20/40/65/80MSPS AND ANTI-ALIASING FILTER.
ADCs with function amplitude detector not required anti-aliasing filter ,sample-hold switch and may have (on contemporary element base)
up to 1000MSPS ,analog bandwith 500MHz(BY NYQUIST).
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