Microwave imaging system

A method of generating a 3-D map of a body, the method comprising:

• (a) irradiating the body with coherent microwave radiation having a first frequency and transmitted by a source,
• (b) detecting at a plurality of locations around the body an amplitude and a phase of radiation that has passed through, or has been reflected by, the body,
• (c) determining at each location the phase of the received radiation relative to a reference signal indicative of the phase of the transmitted radiation at the first frequency to produce a holographic image of the body,
• (d) repeating steps (a) to (c) at least once further with coherent microwave radiation having a different frequency to the first frequency to produce at least one further holographic image of the body, wherein step (d) is completed within 250 ms of steps (a) to (c), and
• (e) processing the first holographic image in combination with the at least one further holographic image to calculate positions in three dimensions of localized physical parameters within the body.