Synthetic aperture imaging with intensity-only data
For imaging applications where phase information is unavailable, this method achieves coherent imaging without phase recording, but it is an incremental improvement over existing phase retrieval techniques.
The paper presents an algorithm that recovers field cross-correlations from intensity-only synthetic aperture data, enabling coherent imaging as if full phase information were recorded.
We consider imaging the reflectivity of scatterers from intensity-only data recorded by a single moving transducer that both emits and receives signals, forming a synthetic aperture. By exploiting frequency illumination diversity, we obtain multiple intensity measurements at each location, from which we determine field cross-correlations using an appropriate phase controlled illumination strategy and the inner product polarization identity. The field cross-correlations obtained this way do not, however, provide all the missing phase information because they are determined up to a phase that depends on the receiver's location. The main result of this paper is an algorithm with which we recover the field cross-correlations up to a single phase that is common to all the data measured over the synthetic aperture, so all the data are synchronized. Thus, we can image coherently with data over all frequencies and measurement locations as if full phase information was recorded.