Experimental Validation of Photonics based Dechirping Approach for FMCW Radar Receivers

This paper addresses the challenge of enhancing target detection capabilities in Frequency Modulated Continuous Wave (FMCW) radar systems .This is achieved through the introduction of photonic technologies to overcome the limitations of conventional RF circuitries that restrict radar waveform instantaneous bandwidth with low range resolution. At the receiver, the dechirped signal can be directly obtained with the usage of an electro-optic modulator and a photo detector along with a suitable electrical filter. In this work, we report an innovative photonics based dechirping approach of a FMCW radar receiver through mathematical analysis and modelling using a standard simulation environment. Further this analysis and modelling results are verified experimentally. This benchtop level validations were carried out by considering waveforms having instantaneous bandwidth upto 4GHz for the detection of target at 7.5 km simulated using optical delay lines. This method can be extended for even pulse radar systems with modifications in post processing.