Additive Phase Noise Pt. 3

In the 3rd and final part of the Mini-Circuits series on amplifier additive phase noise testing at Mini-Circuits, they continue their investigation into cascaded amplifiers. Part 2 considered two identical amplifiers in series and four identical amplifiers in parallel. However, they were unable to demonstrate the improvement in 1/f noise provided by the parallel configuration due to equipment noise floor limitations. In Part 3, they address this limitation by driving the four parallel amplifiers with a single amplifier, all identical, and demonstrate that the cascaded performance is dominated by the single driver amplifier. Mini-Circuits also describes how to best optimize the input power levels into each amplifier in order to avoid regions of high AM-to-PM distortion and achieve optimum performance over a wide bandwidth.

Courtesy of Mini-Circuits