January 13, 2010 in Pacific Northwest National Laboratory
SCADA Principles of Operation
Interface with Physical Devices
* Remote terminal unit (RTU)
* Intelligent electronic device (IED)
* Programmable logic controller (PLC)
Communications
* Directly wired
* Power line carrier
* Microwave
* Radio (spread spectrum)
* Fiber optic
January 11, 2010 in Pacific Northwest National Laboratory
A novel wideband millimeter-wave imaging system is presently being developed at Pacific Northwest National Laboratory (PNNL) that will allow rapid inspection of personnel for concealed explosives, handguns, or other threats. Millimeterwavelength electromagnetic waves are effective for this application since they readily penetrate common clothing materials, while being partially reflected from the person under surveillance as well as any concealed items. To form an image rapidly, a linear array of 128 antennas is used to electronically scan over a horizontal aperture of 0.75 meters, while the linear array is mechanically swept over a vertical aperture of 2 meters. At each point over this 2-D aperture, coherent wideband data reflected from the target is gathered using wide-beamwidth antennas. The data is recorded coherently, and reconstructed (focused) using an efficient image reconstruction algorithm developed at PNNL.
