Microwave analog optical links using suboctave linearized modulators

Abstract

We report experimental links at frequencies up to 4 GHz which use two integrated optical Mach-Zehnder interferometric modulators in series to reduce third-order intermodulation distortion. This design improves the intermodulation-free dynamic range (up to 88 dB with 1 MHz noise bandwidth is demonstrated) with no noise figure penalty relative to a link using a standard modulator. Detector current is low (<2 mA), which is necessary for the detector to provide adequate linearity.