Millimeter Wave FAQ's

Q.) What are Millimeter Waves (MMW)?
A.) Millimeter waves are naturally occurring forms of electromagnetic wave energy ranging from approximately 30 GHZ to 300 GHZ, or 10 nm to 1 nm is wavelength.

Q.) What are passive Millimeter Waves (MMW)?
A.) Brijot’s WDS product is a passive MMW system and does not generate or emit energy of any type, rather only receives millimeter waves from the scene. In much the same way a CCD system “sees” the light waves reflected by bodies and objects, the Brijot MMW system “sees” by receiving the MMW energy that is generated by bodies and objects in its field of view.

Q.) What are active Millimeter Waves (MMW)?
A.) Active MMW systems generate and transmit energy to the subject, similar to radar, sonar and x-rays.

Q.) How do they Millimeter Waves (MMW) compare to the X-rays, Gamma rays, etc?
A.) MMW wavelengths are large relative to the microstructure of most materials, millimeter waves tend to pass through most materials such as clothing whereas light, infrared waves, X-rays and Gamma rays (which have much smaller wavelengths) are not able to pass through many of these same materials.

Q.) What are the advantages of passive systems?

• Emits no radiation or energy of any kind.
• Does not require subject cooperation.
• Images 5-45 feet away, providing standoff threat detection.
• Images only differences in the millimeter wave density of objects. The system will not image a detailed form of person creating a potential privacy issue.
• Minimizes “clutter” which assists in the elimination of false positives and improves the identification of actual threats.
• Reduces installation engineering. There is no illumination component to calculate, consider and calibrate.
• Reduces operation and service support costs. Active systems require highly trained personnel for daily operation and daily support/calibration.
• System size, power and cost are magnitudes lower for the GEN 2 system versus any known active system.
• Can operate virtually anywhere. Operates under extreme temperature conditions and is waterproof.
• Processes up to 50 objects simultaneously with a maximum detection time of 0.3 second.
• Provides object classification to identify specific object types.
• Provides object detection indication combined with full-motion video to pinpoint suspicious objects.
  

Q.) What are the disadvantages of active systems?

• Must radiate/illuminate the target.
• Can only see where “illuminator” is pointing. 100% accuracy of radiation emitter is imperative to system performance.
• Active systems only have “snapshot” capabilities, requiring the radiated subject to stand still or hold a position.
• Requires personnel to gain the cooperation of the target.
• Images only “inches” away. The subject must be properly positioned a few inches from the system for imaging.
• Images anything and everything on target which results in “clutter” adding to the sophistication required (by a human operator or a software application) to distinguish the difference between threatening objects and non-threatening objects.
• Sees virtually everything, including the nuances of the human body.
• Initial cost plus operational cost very high compared to GEN 2 passive system.