1 Introduction

There is an insatiable thirst for improved phase noise performance from clock and LO synthesizer sources in critical radar and communication systems. The LMX2820 integrated PLL/VCO synthesizer is a very low noise synthesizer solution with programmable frequency from 45 MHz to 22.6 GHz. For applications where squeezing every drop of phase noise performance is important, combining the output of two LMX2820 outputs is an easy and straightforward approach to getting a modest phase noise performance improvement.