EMXOs boost oscillator performance with lower power consumption and reduced size 
Advances in the evacuated miniature crystal oscillator (EMXO) manufacturing process have enabled EMXOs to achieve performance comparable to oven-controlled oscillators with lower power consumption and lower cost. While describing the performance of EMXOs, this article discusses its benefits in satellite applications and provides a design example....

Direct digital synthesis enables digital PLLs 
Direct digital synthesis, together with a DAC and a high-performance digital phase detector, overcome several fundamental drawbacks in analog PLLs, such as asymmetry in the phase detector or bandwidth limitations and phase noise in the VCO. Furthermore, because the circuitry is digital, feedback-loop parameters are adjusted by changing numerical coefficients in device registers rather than changing electrical parameters in physical components, the latter process being especially difficult for ASIC designs....