A Gunn oscillator at 3mm waveband has been phase-locked to a synthesizer local oscillator using a high T_(c)YBa_(2)Cu_(3)O_(7-δ) Josephson junction operated at 77K as the harmonic mixer,with harmonic numbers up to 52...A Gunn oscillator at 3mm waveband has been phase-locked to a synthesizer local oscillator using a high T_(c)YBa_(2)Cu_(3)O_(7-δ) Josephson junction operated at 77K as the harmonic mixer,with harmonic numbers up to 52.The observed spectrum of the phase-locked output at the intermediate frequency(IF)shows clearly that the quality of the phase-locking is very good.To drive the analogue phase locking loop successfully,it is essential to have IF output and signal-to-noise ratio both as high as possible.展开更多
基金Supported by the National Center for Research and Development on Superconductivity of China.
文摘A Gunn oscillator at 3mm waveband has been phase-locked to a synthesizer local oscillator using a high T_(c)YBa_(2)Cu_(3)O_(7-δ) Josephson junction operated at 77K as the harmonic mixer,with harmonic numbers up to 52.The observed spectrum of the phase-locked output at the intermediate frequency(IF)shows clearly that the quality of the phase-locking is very good.To drive the analogue phase locking loop successfully,it is essential to have IF output and signal-to-noise ratio both as high as possible.