Analog Devices

The appetite for high data rate and ubiquitous terrestrial connectivity has stimulated huge investment in low Earth orbit (LEO) constellation systems. Low orbit significantly reduces launch and equipment costs, cuts latency by 20× compared with GEO links, and manages bandwidth and users more efficiently.

Digital filters provide a meaningful way of controlling the input spectra of communication systems over a wide range of applications. They can filter harmonics or isolate frequency bands to prevent intersymbol interference while saving you from the hassle of part procurement, PCB layout, and variations that come with their analog counterpart.

This article details performance measurements vs. predictions of a 16-channel S-band direct sampling receiver design. The design is based on recently released direct sampling analog-to-digital converters (ADCs) clocked at 4 GSPS and sampling in the second Nyquist zone of the converter.