| 摘要 |
The present invention is an inexpensive, hand-held, and easy to operate millimeter-wave detection device that employs a non-imaging sensor which radiates a pulse of millimeter waves of a certain amplitude and frequency towards a target located at a distance from the detection device. The sensor receives pulses of millimeter waves that are reflected from the target and generates a voltage waveform that is characteristic mainly of the target material, while other parameters such as distance to the target are known. The processor of the detection device measures both the peak voltage and the rate of increase of the voltage until it reaches the maximum. Using an algorithm stored in a software module, the deviation between the rate of the voltage rise and the peak voltage is compared with values of similar parameters for a number of test targets made of different materials that were previously collected and stored in a calibration table in the memory of the device. A concealed object, e.g. a weapon, is positively identified when the measured voltage rise is found to be similar to one of the stored voltage rises. The circuitry of the detection device generates a visual and/or audio output to a display device which is indicative to the operator as to whether a concealed object is present and, if a match is found with the data in the calibration table, the nature of the concealed object is also displayed. In addition to the basic mode of operation described, various other operation modes can be employed with the detection device of the invention. |
