optical vector network analysis based on microwave photonics
Several novel approaches to perform an optical vector network analysis (OVNA), using optical double-sideband (ODSB) modulation are proposed. The conventional microwave-photonic-based optical vector analysis is realized using optical single-sideband (OSSB) modulation, which has many limitations. For instance, in the OSSB-based approach, the implementation of the OSSB modulation is critical, which should have a broad electrical bandwidth, high modulation linearity and a large operational wavelength range. In addition, the OSSB-based frequency sweeping can only scan one side, so the measurement range is limited by the bandwidth of the microwave components (usually less than 40 GHz), and the measurement accuracy is restricted by the high-order sidebands. The proposed technique measures the optical spectrum responses by taking use of both the ±1st order sidebands without spectrum response aliasing, thus can double the measurement range eliminate the measurement errors produced by high-order sidebands.