In this work we report on a fully integrated photonic chip test structure, providing optical amplitude and phase, frequency and time domain resolution for on-chip devices under test. The structure is based on optical frequency domain reflectometry, and compared to previous approaches, and by suitable design, it allows for retrieving full-field information on the device under test through a single pair of input/output optical ports, with inherent waveguide dispersion de-embedding. As a proof of concept, an experimental demonstration is performed for an arrayed waveguide grating fabricated on a silicon nitride photonic integration platform.