Non-invasive microwave analysis systems and methods determine scattered phase data for a liquid in a container. A transmitter antenna situated within coupling liquid separated from the container by a flexible membrane transmits microwaves that scatter from the container and the liquid in the container. One or more receiver antennas within the coupling liquid convert the microwaves into microwave electronic signals that are processed to determine the scattered phase data.Non-invasive microwave analysis systems and methods image a portion of a biological subject. A transmitter antenna situated within coupling liquid separated from the subject by a flexible membrane transmits microwaves that scatter from the container and the subject. One or more receiver antennas within the coupling liquid convert the microwaves into microwave electronic signals that are processed to reconstruct a cross-sectional image of the subject.