Precise Multiple Frequency Identification Based on Frequency-to-Time Mapping and Cross-Correlation

Abstract

We propose and demonstrate a microwave frequency identification system based on frequency-to-time mapping (FTTM) and cross-correlation. The unknown microwave signals and the bidirectional chirped microwave probe signal are mixed by using a dual-drive Mach-Zehnder modulator. The mixing products are equivalently selected by a dispersion induced photonic filter and converted into electrical pulses in time domain. The unknown frequency is measured by calculating the time interval of the pulses. Moreover, a scheme based on cross-correlation is proposed to eliminate the noise interference for the pulse position acquisition. Experimentally, single and multiple frequency identification from 2-14 GHz is successfully demonstrated, and the measured frequency errors are less than ±3 MHz.