Illumination source for millimeter wave imaging

A method of generating images using millimeter wave energy, the method comprising:

• illuminating a subject with millimeter wave radiation produced by at least two millimeter wave radiation sources, wherein said illuminating comprises:
• polarizing a first millimeter wave source with a first polarization;
• polarizing a second millimeter wave source with a second polarization;
• and
• modulating the first and second radiation source to produce modulated millimeter wave radiation, wherein modulating comprises first modulating the first millimeter wave source with a first modulation that alternates the states of the radiation source between a first state and a second state and second modulating the second millimeter wave source with a second modulation that alternates the states of the radiation source between said first and second states;
• generating a first image of the subject using the millimeter wave radiation detected by a millimeter wave sensor when the first radiation source is in the first state;
• generating a second image of the subject with the millimeter wave radiation detected by the millimeter wave sensor when the second radiation source is in the first state;
• analyzing the generated images to detect representations corresponding to objects associated with the subject, wherein the analyzing comprises identifying an object in the generated images based on properties of an object identified in the first image properties of the same object in the second image with respect to millimeter wave radiation.

An apparatus for detecting concealed objects, comprising

• at least a first modulated millimeter wave radiation source which illuminates a subject with millimeter wave radiation having a first polarization, wherein said modulated millimeter wave radiation source modulates between at least a first illumination state and a second illumination state;
• at least one second millimeter wave source which illuminates a subject with millimeter radiation having a second polarization and a second modulation that alternates the second wave source between a third state and a fourth state
• a millimeter wave sensor which receives millimeter wave radiation from the subject;
• and
• a synchronization unit that produces a synchronization signal, wherein the synchronization signal contains information regarding the modulation of the radiation sources,
• wherein the millimeter wave sensor comprises:
• a millimeter wave imaging sensor;
• a switch operatively coupling the synchronization unit to each of at least two integrators, wherein the switch is controlled by the synchronization unit such that the synchronization signal operates the switch, and further wherein
• the first integrator is activated by the switch to generate first image data from millimeter wave radiation detected by said imaging sensor when the first radiation source is in the first illumination state;
• and
• the second integrator is activated by the switch to generate second image data from millimeter wave radiation detected by said imaging sensor when the second radiation source is in the third illumination state, wherein the first integrator is de-activated when the second integrator is activated, and vice-versa.

An apparatus for detecting concealed objects, comprising

• at least one first millimeter wave source which illuminates a subject with millimeter wave radiation having a first polarization and a first modulation that alternates the first wave source between a first state and a second state;
• at least one second millimeter wave source which illuminates a subject with millimeter radiation having a second polarization and a second modulation that alternates the second wave source between a third state and a fourth state,
• a millimeter wave sensor which receives the millimeter wave radiation reflected from the subject, and generates an image which is analyzed to detect image representations corresponding to concealed objects;
• and
• a synchronization unit operatively coupled at least one of the millimeter wave sources, wherein the millimeter wave sensor includes:
• a millimeter wave imaging sensor;
• a plurality of integrators;
• a formatter operatively coupled to the plurality of integrators and synchronization unit;
• a switch operatively coupling the imaging sensor to each of the plurality of integrators, wherein the switch is controlled by the synchronization unit and wherein the plurality of integrators includes:
• a first integrator receiving from the switch a first image corresponding to when the at least one first source is in the first state;
• a second integrator receiving from the switch a second image corresponding to when the at least one first source is in the second state;
• a third integrator receiving from the switch a third image corresponding to when the at least one second source is in the third state,
• a fourth integrator receiving from the switch a fourth image corresponding to when the at least one second source is in the fourth state, and wherein
• the synchronization unit is configured to provide a first synchronization signal to the at least one first source, and a second synchronization signal to the at least one second source, and further wherein the first and second synchronization signals operate the switch, and further wherein
• the formatter receives all four images and configures the images using the synchronization signals.

A method of generating images using millimeter wave energy, the method comprising:

• illuminating a scene with millimeter wave radiation produced by at least one first millimeter wave radiation source having a first polarization;
• illuminating a scene with millimeter wave radiation produced by at least one second millimeter wave radiation source having a second polarization;
• first modulating the first radiation source to produce modulated millimeter wave radiation, wherein the modulation includes alternating the states of the radiation source between a first state and a second state;
• second modulating the second radiation source to produce modulated millimeter wave radiation, wherein the modulation includes alternating the states of the radiation source between a third state and a fourth state;
• generating a first image with a millimeter wave sensor using the millimeter wave radiation detected from the scene when the first radiation source is in the first state;
• generating a second image with the sensor using the millimeter wave radiation detected from the scene when the first radiation source is in the second state;
• generating a third image with the sensor using the millimeter wave radiation detected from the scene when the second radiation source is in the third state;
• generating a fourth image with the sensor using the millimeter wave radiation detected from the scene when the second radiation source is in the fourth state;
• and
• analyzing the generated images to detect representations corresponding to objects within the scene, wherein the analyzing comprises identifying an object in the generated images based on the reflective properties of an object identified in the first and third images and emissive or transmissive properties of the same object in the second and fourth images with respect to millimeter wave radiation.