Arbitrary Waveform Generators (AWG) have always been incorporated in RF signal generation systems to generate complex modulations, analog or digital. Traditionally, AWGs generated real or complex (I/Q) baseband signals to feed modulators.
As AWGs grew in bandwidth, linearity, and accuracy, a new approach was possible. Instead of generating the baseband signals, it was possible to generate an already modulated IF signal. The final RF frequency was then achieved through a mixer. However, mixers and L.O. add their own impairments
The continuous advances in DAC and memory technologies have increased bandwidths and sampling rates for AWGs to the 10GHz range and beyond, while the improved signal processing capabilities have resulted in the incorporation of real-time interpolators, IQ Modulators, and NCOs to implement Digital Up-Converters (DUC). This allows for the direct generation of modulated RF signals in the UHF, L, S, C and X Bands. This approach can support extremely high modulation BW, well beyond 2GHz, and reduce the complexity and cost while improving flexibility and channel density, which is especially useful for today’s radar (i.e. AESA radars) and wireless communication systems (i.e. Massive MIMO).