A novel differential incoherent heterodyne continuous-wave radar receiver architecture with increased phase sensitivity

This work presents a novel heterodyne radar transceiver architecture based on two separate, incoherent radio frequency (RF) sources. Unlike conventional continuous-wave (CW) radar systems, the proposed approach measures the square of the channel transfer function, resulting in doubled phase sensitivity. This enhancement arises from a di erential evaluation of the downconverted intermediate-frequency (IF) signals, which enables precise tracking of phase changes without requiring phase-locked local oscillators. The associated signal-processing and calibration methods are derived, allowing for accurate reconstruction of the dynamic target response, even in the presence of static reflections and without needing knowledge of the calibration target’s absolute position. Additionally, the e ect of oscillator phase noise is evaluated. Experimental validation using high-precision linear motion confirms that the system accurately tracks target displacement and delivers results comparable to those obtained with a commercial vector network analyzer (VNA). By eliminating the need for RF phase synchronization between transceivers, the architecture significantly reduces hardware complexity and is well-suited for integration and miniaturization. Although demonstrated with a single transceiver pair, the method scales naturally to multichannel configurations, enabling low-complexity multiple-input–multiple-output (MIMO) radar systems with enhanced sensitivity.