Abstract: A smart card (50) transfers information between the smart card and an external system (24) while having the capability of being accessed by a user. The smart card includes a microprocessing unit (MPU) (18) for executing instructions stored in memory, a display (28), coupled to the MPU, for displaying information, a keypad (26), coupled to the MPU and to the display, for entering data by the user, an interface (54,56) for transferring signals between smart card and the external system when the smart card is coupled to the external system, and photovoltaic cells (52) for providing power to the smart card when the smart card is exposed to light. The smart card does not require the use of a bulky and inflexible battery and since the solar cells used are flexible, the flexibility of the smart card is maintained.

Abstract: A personal identification system includes a number of antenna preamplifier nodes coupled to collection nodes which are in turn coupled to a central computer. A personal detector unit attached to a user is inserted into an enclosure of the antenna preamplifier node. The antenna preamplifier node is electrically isolated by RF attenuation material. An antenna of the antenna preamplifier node is a low gain antenna. The antenna preamplifier node reads a coded radio frequency signal of a personal detector unit inserted into an enclosure and rejects signals of other various personal detector units in the vicinity.

Abstract: A body detector (10) detects when a body (12) is absent from a region (26) being monitored. The body (12) has a different dielectric constant than air. The region (26) is configured as a capacitor (20) in which the body (12), if present, serves as a dielectric. The capacitance of the capacitor (20) is measured (28). This measurement influences a baseline value (30). The capacitance is measured (38) a second time. The second measurement is checked to verify that it is within minimum (42) and maximum (46) values. In addition, it is checked to verify that it is within a more narrow range (54) that is defined in response to the baseline value. The second measurement is then used to adjust the baseline value and the process repeats. The range (54) within which the capacitance must stay slowly adapts to changes in the capacitance of the capacitor (20). Abrupt changes in the capacitance cause an alarm to be annunciated.

Abstract: A non-intrusive mounting system and method for coupling microwave instruments to a container flange having an opening into a container. The mounting system includes a microwave transparent window and a mounting flange having a window recess for accommodating the microwave transparent window. The microwave transparent window is compressively fastened over the container opening between the mounting flange and the container flange. Microwave instruments such as radar level sensing apparatus can be mounted on and removed from the mounting flange without breaking the seal to the container.

Abstract: A transmitter (12) broadcasts a PN encoded message (16). A receiver (14) includes a SAW correlator (38) configured to autocorrelate with the PN sequence used in the broadcast signal. A preamble of the message (16) conveys two successive bits (18) that are each encoded with the PN sequence. After the correlator (38) has been preloaded with the PN sequence from the first bit (18), its non-correlation output exhibits reduced amplitude time sidelobes. A timing comparison circuit (60) compares a correlation signal (46) with a timing threshold (72). The timing threshold (72) is established at a very low level to minimize the influence of multipath. False triggering on noise is prevented by disabling the timing comparison circuit (60) until after the first bit (18). At this point in time the correlator (38) has been preloaded with its PN sequence, is again being loaded with its PN sequence, and outputs reduced amplitude time sidelobes.

Abstract: An optical target detector utilizes a star coupler to achieve automatic alignment of "pencil" laser beams. A number of "pencil" beams of laser light are deployed from the surface of a projectile in order to detect a target. The laser light is transmitted to the target and reflected back from the target to the optical target detector. The light tramsmitted, in the form of a number of "pencil" beams, and the light being reflected by the target are transmitted through a star coupler device in order to maintain alignment for the transmission of maximum light signal strength and simultaneously to minimize aerosol backscatter.