Until recently, it was rather unusual to find a data converter that claimed viable operation in Nyquist zones beyond the first two ‘baseband’ zones. In fact, it’s so unusual that many engineers may not even be aware of the potential benefits that derive from such a capability. That’s easy to explain, as most traditional, high speed CMOS designs are limited to bandwidths of a few gigahertz. This is fine for use in a wide variety of RF designs, but it certainly limits the use of such converters in the microwave domain. Ultra-wideband system design has therefore been driven to adopt complex multi-channel approaches with multiple local oscillators, mixers and converters operating in ‘parallel’ to cover the broadband range.
Radio technology has transitioned from complex analog, super-heterodyne designs into software defined, highly flexible digital architectures. For many RF engineers who have grown up experiencing this transformation, there’s a pent-up demand to see a similar development at microwave frequencies. We are entering a period when software defined microwave systems (SDMS) are fast becoming a reality. Their development is spawning new applications, creating new system price points.