Phase noise analysis of a tuned-input/tuned-output oscillator based on a GaN HEMT device
Paper i proceeding, 2014

This paper reports on an experimental analysis of phase noise in a tuned-input/tuned-output oscillator based on a bare-die GaN HEMT device. To investigate phase noise dependency on resonator coupling factor (β), the circuit is designed with flexibility to modify the resonant tank, in terms of unloaded quality factor (Q 0 ) and impedance level. The reflection coefficient (Γ amp ) from the reflection amplifier can also be varied. With exception for very high values of Γ amp , the circuit is robust to variations in β. It is more important to choose a bias point where the flicker noise is low and the power reasonably high. A minimum phase noise of -150dBc/Hz @ 1MHz off-set from a 1GHz oscillation frequency and a power normalized figure of merit (FOM) of 186 are reached. An interesting analytical result is also presented; power normalized figure of merit, commonly used for benchmark of oscillators is bound by Q 0 and can be related to the theoretical noise floor limit.


phase noise




Mikael Hörberg

Chalmers, Mikroteknologi och nanovetenskap (MC2), Mikrovågselektronik

Szhau Lai

Ericsson Sweden

Thi Ngoc Do Thanh

Ericsson Sweden

Dan Kuylenstierna

Ericsson Sweden

44th European Microwave Conference, EuMC 2014 - Held as Part of the 17th European Microwave Week, EuMW 2014; Fiera di RomaRome; Italy; 6 October 2014 through 9 October 2014



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