Computer Aided Design and Alignment of a Tunable Low Noise Dielectric Resonator Oscillator

The design of a 4 GHz low noise microwave oscillator for use in carrier supplies for high capacity digital radio systems is described. The oscillator is based on planar circuit technology and a high Q dielectric resonator. The structure is well suited for modelling, computer aided design techniques and allows low cost production. By careful design excellent experimental results are achieved, measured phase noise at 10 kHz offset is below ¿130 dBc/Hz, at least 10 dB lower than previously published results | 1, 2, 3 |. Finally a novel computer assisted alignment procedure is decribed, allowing low production cost despite tough specifications.