High IF Sampling Puts Wideband Software-Defined Radio Within Reach

Multiband radar and electronic warfare (EW) applications put a high value on wideband, high dynamic range, agile spectral monitoring. Increasingly higher sample rate data converters are allowing architecture changes to the radio front end that shrink size, weight, power, and cost (SWaP-C), maintain performance, and evolve toward software programmable common hardware. We’ll explain the technology advancements enabling this age of wideband software-defined radio-expected to transform EW and multi-band radar architectures.The discussion follows a series of frequency planning figures that show the progression of improved wideband spectral scanning methods enabled by advancing data converter technology. The example carried through is a 500 MHz to 18+ GHz EW digital receiver. The annotated figures show for a given approach why the frequency planning is necessary and what allows successive improvements to SWaP-C and flexibility while maintaining dynamic range. In the progression of improving schemes, you’ll see the receiver RF image gets easier to address,which allows software-defined flexibility. The need for tunable preselection to kill multi-tone IMD2 doesn’t change with the approach and will remain a critical need into the future even as direct sampling grows ever wider.