Low Noise Figure Microwave Photonic Link

The noise figure of an analog fiber-optic link was reduced to 6 dB at 1 GHz by using a bias-shifted Mach-Zehnder modulator with an optical input power of 1 W. The link noise figure was less than 14 dB for modulation frequencies from 1-18 GHz. This level of performance was achieved without electronic pre-amplification. A linearized microwave photonic link using this noise reduction approach has been demonstrated with a spurious-free dynamic range of 130 dB in a 1 Hz bandwidth.