Comparison PM noise of BJT and MOSFET oscillators

This article presents a technique for designing low-noise BJT and MOSFET Clapp oscillators. Opportunities to use noise compressing feedback resistors inserted in emitter (source) circuit were investigated. For BJT and MOSFET oscillators, those were calculated using algorithm of parametric synthesis, minimal values of PM noise power spectral densities were found and compared. Some limitations of this approach to the problem of PM noise reduction in BJT and MOSFET oscillators were found and discussed.