Injection Locked DRO Synchronized by Multitone Signal

Behaviour of the injection locked dielectrics resonator oscillator (ILDRO) synchronized by the external multitone signal was investigated. Subject of this investigation was the possibility of synchronization many DRO (at different frequencies) symultaneously. Principles of injection locking are also used for decreasing the phase noise level of a DRO. As a consequence of a good temperature stability of DROa very small level of injected signal for phase synchronization are needed. Nonlinear model of microwave transistor is used for the computer simulation of phase locking. In order to minimize the unmanted components of injected signal at the DRO output, the bias and the level of input signal were optimized. Injected signal was a crystal stabilized oscillator signal at 250 MHz, multiplied by the comb generator. DROwas synchronized by the 42-nd harmonic (at 10,5 GHz). At the DRO output power level of 41-st and 43-rd harmonics were 60 dB below the carrier. Power level of the output signal was over 10 dBm with the phase noise level of -85 dBc/Hz at 1 kHz offset.