One-gigahertz low-phase-noise oscillator for on-board avionic applications

The aim of this paper is the presentation of a low phase noise 1 GHz oscillator developed by A.R. Electronique for tactical on board avionic applications. The typically requested performances for UHF oscillators in radar applications are: low phase noise level under vibrations; high harmonic purity; small frequency deviation in an extended range of temperature; compact volume. To reach this level of performance, A.R. Electronique has developed a design based on the use of a VHF AT cut crystal with optimized low g sensitivity parameters. The XTAL oscillator frequency is multiplied and filtered by a specific dielectric filter to obtain the UHF signal. Finally, an amplifier matches the signal at standard power level. After the description of the quartz optimization, its oscillator and the other parts of the electronic structure, we show experimental results obtained with this UHF oscillator such as: g sensitivity measurement in 3 axes (<5.10-10/g in the worst axis); phase noise in inert and under vibration conditions; thermal behavior (<20 ppm peak to peak in [-55, +95]°C); spectral purity (<-60 dBe for spurious and subharmonics)