Direct sampling receivers convert received signals directly to digital signals for subsequent processing. Direct sampling receivers offer flexibility of use over multiple frequency bands and can improve performance using digital filters that replace less accurate analog counterparts. Speed limitations of analog-to-digital converters (ADCs) implemented within direct sampling receivers limit the performance of ADCs at high sampling frequencies, especially when higher resolution is required.
Comparators are the fundamental building blocks of many types of ADCs and generally dictate the power, performance, and speed of operation of an ADC. Comparators have limitations that lead to significant limitations in the performance and power consumption of ADCs, which negatively impact the overall performance of digital sampling receivers and other devices that include ADCs.