Abstract: A cipher-key distribution system used in a one-way communication from a first party to a second party. The cipher-key distribution system is composed of a first subsystem, a second subsystem, and a common file which stores information publically accessible by the first and second subsystems. The first subsystem generates a cipher-key based on a constant, receiving party identifying information, a random number, and public information from the common file. The first subsystem also generates a key distributing code based on a constant, a random number and a first secret information and transfers the key distributing code to a second subsystem. The second subsystem receives the key distributing code and information for identifying the first party and generates a second cipher-key identical to the cipher-key generated by the first subsystem. The second cipher-key is created from the information for identifying the first party, a second secret information, and the key distributing code.

Abstract: A packet data transmission system is used to link a number of remote hand-held data-gathering units such as bar code readers to a central computer which maintains a database management system. Data packets are sent from the remote units by an RF link to intermediate base stations, then sent by the base stations to the central computer by a serial link. Direct sequence spread spectrum modulation is used for the RF link. The remote hand-held units initiate an exhange using RF transmission to and from the base stations, receiving only during a rigid time window following a transmission from the remote unit. The base stations cannot initiate communication to the remote units, but instead send data to the remote units only as part of the exchange.

Abstract: A pseudorandom, iterative method and apparatus for automatically creating an address for each remote unit of a data communication network comprising a plurality of remote units, such as the seat electronic units (17) of a passenger aircraft, and a central unit, such as a central transmitter/receiver unit (13). The formats of the message frames that control the flow of data between the central unit and the plurality of remote units includes a synchronization word, a command word, and a series of data word segments. The number of data word segments is equal to or greater than the number of remote units. The pseudorandom, iterative method and apparatus assigns addresses such that one and only one remote unit is associated with a data word segment position. First, the central unit transmits an ADDRESS ASSIGN PHASE 1 command to each remote unit. In response, each remote unit randomly selects a data word segment position and replies to the central unit in the selected position.

Abstract: A decoder for descrambling encoded satellite transmissions comprises an internal security element and a replaceable security module. The program signal is scrambled with a key and then the key itself is twice-encrypted and multiplexed with the scrambled program signal. The key is first encrypted with a first secret serial number (SSN.sub.1) which is assigned to a given replaceable security module. The key is then encrypted with a second secret serial number (SSN.sub.0) which is assigned to a given decoder. The decoder performs a first key decryption using the second secret serial number (SSN.sub.0) stored within the decoder. The partially decrypted key is then further decrypted by the replaceable security module using the first secret serial number (SSN.sub.1) stored within the replaceable security module. The decoder then descrambles the program using the twice-decrypted key. The replaceable security module can be replaced, allowing the security system to be upgraded or changed following a system breach.

Abstract: The method of permitting the execution of a disk loaded into the disk drive, the disk having a plurality of tracks, comprising the steps of writing data in non-standard format and length to a normally unaccessible track of the disk, the data including an encrypted password, the password being located at an arbitary location within the data, reading the data resulting in an error signal, locating an indexing position and applying an offset to identify the password, and unencrypting and authenticating the password in order to execute the disk.

Abstract: Apparatus is provided for switching traps in and out of a cable television signal path. A plurality of double pole double throw switches is connected in series with the signal path. Each switch has a first actuated position, a second actuated position, and an off position. The switches connect corresponding traps to the signal path in the first actuated positions. In the second actuated positions, the switches provide a through connection in series with the signal path. An open circuit is provided along the signal path when a switch is in the off postion. Actuation and disconnect signals transmitted over the cable television network selectively actuate the switches to the frist, second, or off positions. The switches are constructed of solid-state components such as diodes, and are actuated by unipolar biasing signals.

Abstract: A data-locking system for generating an application, includes a data entry device, a video display screen, a storage medium, and a system for locking data in the storage medium. The video display screen allows for the display of inputted information in a predetermined application format comprising an integrated arrangement of critical and non-critical data fields. The data-locking system has circuitry for generating first and second records from the inputted information, as well as circuitry for generating a unique generator key number for encrypting the first record and circuitry for generating a data-lock code number and a time stamp number. When using the data-locking system, the inputted information in the critical data fields of the predetermined application format, once data-locked, cannot be changed.

Abstract: A method of aligning two images of the same scene by matching features in a first image to features in a second image is disclosed. The method comprises identifying edges of objects in the first image using two different processes. The edges identified using both processes are compared and combined into one image representing confirmed edges which are readily identified in other images of the same scene. A template is then formed from the confirmed edges which is matched to a subregion of the second image.

Abstract: A system for the management of computer programs in a computer network environment is presented. A network license server comprises a license server daemon which provides access to a computer program based on information stored in user and license databases. To track software usage, the daemon also maintains a log file which can be accessed by and interfaced with a network administration station. The network license server protects software vendors from unauthorized use of their software while permitting software programs and users to reside anywhere on the network.

Abstract: The useful bandwidth of a bandwidth-limited input signal (s(t)) is reduced, to obtain a coded signal (q(t)) by forming a combined input and feedback signal, low-pass filtering the combined signal, and passing the low-pass filtered signal through a feedback loop which includes symmetrical frequency-voltage (f/V) conversion, substantial amplification, and voltage-frequency (V/f) reconversion, the reconverted signal being combined with the input signal in a multiplier, the coded output signal being derived from the output of the low-pass filter. Amplification of the amplifier is so high that the bandwidth of the resulting frequency-modulated feedback signal is greater than the bandwidth of the original input signal. The resulting coded signal can be decoded by derived scanning signals which are combined with bandwidth-enhanced coded signals and processed in an inversion matrix for subsequent reconstitution of the original signal.

Abstract: An authentication system for electronic information networks having small hand-held portable authenticating devices which are remotely initialized and can use 4 bit microprocessors in a challenge-response security system and yet permit practical communication of the large numbers which are necessary for sufficient security.

Abstract: In a process for the cryptographic processing of data in a cryptographic system, processing takes place in two parts. In the first part the data transmission routines within a data entity and a coded text entity are detected. The clear text and the cryptographic are separately processed cryptographically in the second part and then recombined in the first part with the data transmission routines.

Abstract: The present invention is a dual communication mode sysem that combines a point to point communications device with a television receiver and a video tape recorder. The result is a highly versatile and easily operated personal entertainment and communication center. The point to point communication device included in the personal communication and entertainment center can provide information to: (a) reset the center's time clock automatically if power to the center is interrupted or if the center clock must be synchronized to an accurate time (b) program the personal entertainment and communication center from a remote location; (c) provide authorization signals to allow the personal entertainment and communication center to descramble coded signals received by the television receiver from a source such as a satellite or cable hookup; and (d) provide personal messages which can be recorded on the video tape recorder and displayed on the television screen.

Abstract: A spark gap transmitter mounted in the base plug of a projectile and powdd by the piezoelectric effect of ferroelectric crystals deformed upon projectile impact. The transmitter emits an RF pulse train in the S-band which may be detected by appropriate equipment which compares the impact point with the target location for aim point correction purposes.

Abstract: In an RF communication system, a method for developing and communicating usage context information. When an inbound communication (110) is received from a communication unit (107), a repeater (101) at a base site (100) retransmits the received communication as an outbound signal (114), including usage context information interleaved with the information signal. Communication units are informed of communications of interest occurring over other communication resources without the need for sequential monitoring.

Abstract: A beam-forming network (98) employs one or a plurality of first transmission delay lines (168, 170, 172, 174) for receiving transmit signals (T1-T4) applied thereto, and a plurality of second transmission lines (176), which serve as line summers. Each of the first transmission delay lines has first and second portions (168a, 168b; 170a, 170b; 172a; 172b; 174a; 174b) spaced apart from one another so as to define first and second levels displaced from one another. The set of second transmission lines (176) are arranged in first and second subsets (176a, 176b) which are respectively disposed adjacent to the first and second levels and respectively associated with the first and second portions of the first lines, such that the first subset of second lines is coupled to the first portion of the first lines, and the second subset of the second lines is coupled to the second portion of the first lines.

Abstract: An encryption circuit that operates with substantially zero delay. Using programmable keys and polynomials, the encryption algorithm can be constantly changed to thwart any unintended receiving parties from decoding the data. A key (101) and a polynomial (102) are loaded into registers. The key is then loaded into a shift register and shifted through XOR gates (106) at a programmable rate. The other input of the XOR gates come from the result of ANDing (103) a disable signal, the polynomial register (102), and the last stage of the shift register (104). Eight bits of the shift register outputs are XOR'ed with the input data to be encrypted. The output of these XOR gates (105) is the encrypted data.

Abstract: A method and apparatus for generating low level noise signals are provided. Two random numbers X.sub.1 and Y.sub.1 are first generated and bits 0-4 of the first random number X.sub.1 are extracted to produce a number X.sub.2. A number X.sub.3 is further computed by the formula: X.sub.3 =2.sup.-N (X.sub.2 .multidot.I), where N is a predetermined number and 1.ltoreq.I.gtoreq.2.sup.N -1. Bit 7 of the second random number Y.sub.1 is then extracted and combined as a sign bit with the computed number X.sub.3 to produce a sign-magnitude eight bit number W representing a sample of low level noise encoded in accordance with .mu.-law.

Abstract: In a communications system, a multiframe data signal is sent from a transmit end to a receive end of the system. The multiframe is composed of a series of submultiframes each containing a series of frames. Each frame in turn comprises a sync word for establishing the start timing of the frame, an identifier for uniquely identifying the submultiframe in which the frame is contained, and a specified number of data bits. A pseudo-random scrambling bit pattern, which repeats at intervals of multiframe and varies from one pattern to another at frame intervals, is generated as a scrambling bit pattern with which the data bits of each frame are scrambled prior to transmission. At the receive end, the sync word of each frame is detected to establish frame synchronization. A memory stores initial bit patterns each of which is identical to the pattern which was generated at the beginning of each submultiframe. The identifier is detected when frame sync is established and applied as a read address to the memory.

Abstract: The invention relates to a signal processing method and apparatus for nuclear spectrometers, whereby the peaking time is set, which is optimal from the point of view of the signal-to-noise ratio, where in case of an input signal of staircase shape modulated with noise, the so called base-line filtering interval preceeding the actual signal and the signal filtering interval following the actual signal are chosen so that their widths are equal to the width of the optimal peaking time (T.sub.p), the momentary value measured in the base-line filtering interval (A.sub.i) is subtracted from the momentary value measured in the signal filtering interval (J.sub.i), where said momentary values (A.sub.i and J.sub.i) are measured in the time scale symmetrically with regard to the rising edge of the signal, and the differences (J.sub.i -A.sub.i) are summed with weighting factors (W.sub.i).