Fast optical vector analysis based on dual optical frequency comb and I/Q demodulation

A fast optical vector analysis (OVA) technique based on dual optical frequency comb (OFC) is proposed. Based on the principle of asynchronous optical sampling, the broadband frequency responses can be measured quickly, meanwhile, image rejection is realized by I/Q coherent receiving system, the optical carrier need not to be shifted by an acousto-optic frequency shifter, which improves the utilization efficiency of optical comb. In simulation process, an approximate lorentz linear absorption model of HCN molecule is constructed. The single spectrum of HCN molecule with linewidth of 1 GHz and bandwidth of 10 GHz can be rapidly measured by the proposed OVA system, and the measurement time is only 1 μs in theory.