Abstract: A coin-operated TV system is disclosed that uses separate TV displays or sets, each having an individual coin acceptor, program selector and control. Centralized sources of pre-recorded and/or publicly broadcast programs are provided via TV modulators as separate channels hard wired to every TV set. A computer is also hard wired to every TV control. The computer and TV control provide that each TV set normally receives and exhibits one channel continuously, at no costs. If the program selector at any TV set is switched to another specific channel and the coin acceptor has received a suitable deposit, the computer and TV control shift that particulat TV set to the selected channel. The selected channel will operate for a predetermined duration or until the selected program has ended. Thereafter, the TV set will be shifted back to the free channel, unless a different specific channel had earlier been selected and paid for.

Abstract: A video decoder includes an application specific integrated circuit (ASIC) that has the decoder address and a secure decryption key stored in a one-time-programmable memory. Encrypted messages are received and selectively supplied to a packet decrypter and to a video decrypter based upon the location of bits in the message string. The packet decrypter is responsive to a flag in the packet data for utilizing a secure key or a unsecure key for decryption of the packet data. The information derived from the secure decryption and the secure key itself are never available (or ascertainable) outside of the ASIC. Only information concerning the unsecure key is available outside of the integrated circuit.

Abstract: An off-premises cable television interdiction apparatus provides a microprocessor controller for controlling and switching one or more variable frequency voltage controlled oscillators. The variable frequency oscillators selectively jam only unauthorized premium programming transmitted on particular channels of a broadband signal in the clear from a headend to a subscriber. The microprocessor controller controls the variable frequency oscillators to hop between jamming frequencies and jam particular channels under control from the headend. A frequency calibration routine is executed periodically upon power-up to determine gain parameters for the oscillators. A heterodyned variable frequency oscillator may be provided for the interdiction system which moves the frequency of the variable frequency oscillator out of the television band and mixes the variable frequency oscillator output with a fixed local oscillator output to provide a jamming signal that falls in the television band.

Abstract: The use of chip cards, with the level of security of the type associated with chip cards of the type used by banks, is extended to move widespread use by organizing a secure dispatch of blank chip cards to customers wishing to program specific applications therein. The system consists in sending this customer the blank chip card itself and a programming access key to this card, by separate routes. To prevent any additional risks, the access key is itself enciphered and can be deciphered only be a deciphering element in the possession of the customer. The card can then be programmed only if this card is confronted with its deciphering key.

Abstract: Young's fringes are produced from a double exposure image of particles in a flowing fluid by passing laser light through the film and projecting the light onto a screen. A video camera receives the image from the screen and controls a spatial light modulator. The spatial modulator has a two dimensional array of cells the transmissiveness of which are controlled in relation to the brightness of the corresponding pixel of the video camera image of the screen. A collimated beam of laser light is passed through the spatial light modulator to produce a diffraction pattern which is focused onto another video camera, with the output of the camera being digitized and provided to a microcomputer. The diffraction pattern formed when the laser light is passed through the spatial light modulator and is focused to a point corresponds to the two dimensional Fourier transform of the Young's fringe pattern projected onto the screen. The data obtained froThis invention was made with U.S.

Abstract: A security mechanism is described for a distributed data processing system. Each server in the system maintains a set of security ratings giving its view of the security levels within the system. When a first server wishes to initiate a connection with a second server, the two servers exchange security information, by means of messages, so as to establish an overall security level for the connection, based on a combination of the security information maintained by both servers. However, if the first server decides that the second server cannot be trusted to discuss security, messages are exchanged containing no security information, and each server establishes its own security level for the connection, based on its own locally held security information.

Abstract: A remotely controllable position indicator system arranged to determine the relative position of two bodies and their relative orientation. A movable remote control device is controllable to transmit command radiation signals. A fixed reference station executes commands represented by the command radiation signals. The remote control device has a transmitter while the reference station has a receiver or receivers which monitors the intensity of the radiation received and distinguishes the source of the radiation. A computer is programmed to determine the direction of the reference station from the remote control device using a comparison of monitored intensity of radiation received from the transmitter to give the direction of the receiver from the directional transmitter. One or more of the transmitters is controllable to transmit command signals and the receiver is arranged to receive the command signal.

Abstract: A CATV system includes a main head end as a system center and a plurality of subhead ends. A baseband TV signal is transmitted from the main head end to the subhead ends through optical fiber cables. A scrambling data generating means is disposed in the main head end to generate scrambling data and transmit those together with the TV signal. A scrambling means is disposed in each subhead end to perform a scrambling operation such that synchronization portions of a video signal is compressed on the basis of the scrambling data.

Abstract: In the method, a volume (5) to be measured is illuminated by a pair of light beams (3) which cross each other. The Doppler-shifted scattered light (8) originating from the particles (6) which are moved along with the flow is registered and converted into electric signals (1). The Doppler frequency of the registered scattered light (8) is used as a measure of the flow velocity. The electric signals (1) of the registered scattered light (8) are digitized and represented in the form of an image and a coherent light beam is transmitted through the image. The coherent light beam (14) is focussed in a Fourier plane (18) as a result of which a Fourier-transformed image (22) of the electric signals (1), which exhibits a dot pattern (24), is generated. The Fourier-transformed image (20) is recorded and processed further.

Abstract: A reflector of an antenna in a radar system subject to jamming carries a multiplicity of localized phase shifters which are sequentially controlled by a processor to introduce certain phase modifications into incoming signals reflected toward an associated radiator. The processor, operating on branched-off portions of the incoming signals, compares the magnitudes of the signals received in the several operational states of each phase shifter and maintains that operational state for which the signal level is at a minimum. The comparisons may be carried out on signals received at the end of a signal-transmission cycle, lacking a useful component.

Abstract: A light projector projects a light pulse upon an object being photographed. A position sensitive detector (PSD) receives reflected light from the object and produces photocurrents which depend on the position of incidence of the light thereon. The detector (PSD) is positioned so that the center of an imaging spot formed by the reflected light from the object when the latter is located at infinity is located toward the projector with respect to the center of PSD.

Abstract: In a weapon boresighting system for aircraft and vehicles, an optical square is oriented to a fixed reference line on the vehicle and provides the directionality of a pair of orthogonally positioned of laser illuminated retroreflective catadioptric collimators attached to said optical square whose outputs are directed via one or more deviators or periscopes to a pair of retroreflective catadioptric receivers orthogonally attached to a second optical square positioned at the weapon to be boresighted, each said receiver imaging the laser on a position sensitive sensor, the outputs of the latter indicating the pitch roll and yaw condition at the weapon.

Abstract: Digitized heterodyne signals in a ring laser gyroscope are processed to determine the phase and acceleration of heterodyne signals at turnarounds in the angular motion of the frame of the ring laser. A hybrid analog/digital design that incorporates the necessary logic processes the turnaround data to produce a phase correction that can be added to the gyroscope count to correct phase errors that at each turnaround. Separation of high speed data processing from lower rate data simplifies the code and permits evaluation of turnaround correction performance. A fully digital system determines a phase distribution for the detected turnarounds and processes the phase distributions of the heterodyne signals for a multiplicity of turnarounds to determine an angle towards which the phase distributions are skewed and the amount of that skew.

Abstract: A protective helmet adapted for distributing cooled air to the head of a son comprising an outer shell and an inner lining of open cell foam. A cool air inlet conducts cooled air into the capillary system of the open cell foam where it is distributed throughout the volume of the foam. The cool air exits a multiplicity of pores in the surface of the foam in a randomly oriented fashion, providing cooled air substantially evenly distributed over the head.

Abstract: A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations in the particle beam.

Abstract: A technique for correcting the non-uniform illumination and return echo strength from a mapped area resulting from antenna beam shape and range loss effects in a batch high resolution synthetic aperture radar. The technique involves changing the radar receiver gain in a precisely defined compensating manner and eliminates amplitude roll off at the edges of the display map so that equal target returns are displayed at equal amplitudes at any point of the map. The compensation arrangement requires minimal memory and computational overhead and thereby achieves minimal impact on frame time of the displayed map. The disclosure includes a computer simulation of the radar system performnce and comparison of the simulated before and after compensation radar maps.

Abstract: An apparatus for detecting mechanical vibration in the presence of an electromagnetic pulse, which is of particular use in the testing of land mines. An optical fiber link is provided between the device under test and a remote data collection station. A vibration sensor and optical transmitter are secured to the device under test, while an optical receiver and event latch are present at the other end of the fiber link at the data collection station.

Abstract: An apparatus and method for detecting the presence of liquid in pipes or tubes using ultrasonic techniques A first piezoelectric crystal is coupled to the outside of the pipe or tube at the location where liquid in the tube is to be detected. A second piezoelectric crystal is coupled to the outside of the pipe or tube at the same location along the tube but circumferentially displaced from the first crystal by an angle around the pipe or tube of less than 180.degree.. Liquid in the pipe or tube is detected by measuring the attenuation of an ultrasonic signal sent by the first piezoelectric crystal and received by the second piezoelectric crystal.

Abstract: A printed circuit board having a plurality of traces and pads printed then. Slots or openings of various geometric shapes are formed in the board to provide flexible mounting members. The pads are mounted on the mounting members. Surface-mounted electrical components have their terminals soldered to the pads. The flexibility of the mounting members permits small movements of the soldered joints in response to thermal expansions, vibrations, etc. to control potentionally damaging stresses.

Abstract: A method of identifying the presence, and amount, of elemental constituents in a material. The method uses an apparatus known for use in measuring extended x-ray absorption fine structure, and adapts it to the measurement of x-ray appearance potential in a manner to yield both qualitative and quantitative information about the elemental constituents of the material. The source of x-rays can be a synchrotron, which, because of its high power output, increases the speed and sensitivity of the measurements, permitting the use of less sensitive x-ray detectors to yield statistically significant data.