Abstract: Disclosed is a flow-softening tungsten alloy having the general formula: W100-pAiBjCkDe wherein W is tungsten; A is one or more elements selected from the group consisting of nickel, iron, chromium and cobalt; B is in or more elements selected from the group consisting of molybdenum, niobium and tantalum; C is one or more of the elements selected from the groups consisting of titanium and aluminum; D is one or more elements selected from the group consisting of boron, carbon, and silicon; i is from about 5 to about 8 weight percent; j is from 0 to about 4 weight percent; k is from about 0.1 to about 4 weight percent; 1 is from 0 to about 0.1 weight percent; and p is greater than or equal to about 7 weight percent and less than or equal to about 20 weight percent. In this alloy p is approximately equal to the sum of i, j, k and 1. A method of preparing this alloy and a kinetic energy penetrator manufactured from it are also disclosed.

Abstract: An Adaptive Position Transmission Algorithm (APTA) for mobile radio device where position information is required, using any transmission medium such as high frequency (HF), very high frequency (VHF), ultra high frequency (UHF), Satellite Communications (SATCOM), etc. A mobile radio device employing the APTA provides accurate and automatic position reporting and thus, in a tactical environment improves situation awareness and reduces the probability of fratricide. A mobile radio device employing the APTA also reduces the number of options available to the user thereby simplifying the operation thereof while improving overall performance in most applications. The APTA accomplishes this by monitoring position, time and radio network parameters to determine when stand alone messages will be transmitted. The APTA factors radio network loading with movement and periodic thresholds.

Abstract: There is disclosed a circuit for selectively enabling communications by providing an output signal voltage of a first level indicative of a first transmission state and a second level corresponding to a second non-transmission state, the circuit having an FET having a gate, source, and drain, the source coupled to a first controlling means for providing a voltage Vs to the source, the drain coupled to an output terminal of the circuit for providing the output signal, and the gate coupled to a second control means for providing a voltage Vg to the gate, the FET operable in a first conducting mode when a gate to source voltage Vgs exceeds a predetermined threshold, indicative of a non-zero crossing amplitude region of an input voltage signal, to cause the output signal voltage to be at the second level corresponding to the non-transmission state, and in a second non-conducting mode, wherein the Vgs of the FET is less than the threshold, indicative of a zero-crossing of the input signal, for causing the output s

Abstract: The communication system has a first modem having a digital port for communicating a first data block in a first format between a first transmission channel and the digital port and a second modem having a digital port for communicating a second data block in a second format between a second transmission channel and the digital port. The first data block has a header block and a message block. The controller/processing device comprises a first interface means, a second interface means and a conversion means. The first interface means is adapted for receiving the first data block in the first format from the first digital port. The conversion means is coupled to the first interface means. The conversion means converts the first data block in the first format to the second data block in the second format. The second interface means is coupled to the conversion means. The second interface means is adapted for sending the second data block in the second format to the second digital port.

Abstract: A method of estimating expected errors of environmental data parameters based on radiance measurements obtained from visible infra red radiometric satellite sensors (VIIRS) orbiting the earth, comprising the steps of: obtaining N radiance measurements of a surface body I.sub.I, . . . ,I.sub.N defining matrix I depending on p unknown surface and atmospheric parameters T.sub.i, . . . T.sub.p, defining a matrix T; generating a forward model I=f(T) for obtaining the I radiance measurements from the p parameters; choosing an initial set of values for the p parameters and linearizing f(T) about the initial values to obtain a linearized forward I=s+H.theta. as f.sub.i (T.sub.01, T.sub.02, . . . T.sub.0p)+.SIGMA.H.sub.ij .theta..sub.j where I=1,2, . . . N and .theta..sub.j =T.sub.oj and H.sub.ij =.delta.f.sub.i /.delta.T.sub.j and where .theta. is a column matrix .theta..sub.l, . . . .theta..sub.p and H is a matrix of H.sub.

Abstract: There is disclosed in a digital communications system for communicating between two radios by transceiving a signal comprising a first type control signal, a second type data traffic signal and a third type voice signal, a remote communication interface for providing transmission therebetween comprising a duplexer/bridge network for transceiving the signal, means for determining the signal type to be transmitted, low pass filters and analog to digital and digital to analog converters for processing received and transmitted signals, and a digital signal processor for modulating and demodulating the signal for transmission/reception according to the signal type. There is also disclosed means for adjusting the clock sampling frequency during the demodulation process to obtain bit sync, bit tracking and frequency tracking.

Abstract: An antenna including a plurality of radiating elements disposed in mutually orthogonal pairs arranged in a predetermined pattern to radiate and receive RF signals over multi-octave frequency bands; and divergent lens means to provide stability for the predetermined pattern of radiating elements.

Abstract: A distributed discrete-event simulation system operable for processing time-stamped events in chronological order for simulating a multinode communications network, the simulation system comprising a plurality of subsystem platforms (SPs) operable for transmitting message packets to other SPs for simulating node to node communications; and a system controller coupled via a communication link to the plurality of SPs for controlling synchronization and message packet processing associated with the plurality of SPs; wherein when a time-stamped event is received by one of the SPs, the receiving SP responsive to the time-stamped event triggers execution of tasks associated with the time-stamped event in the other SPs via the message packets to provide parallel task processing for the particular time-stamped event among the plurality of SPs.

Abstract: In a digital communications system for transmitting and receiving digital data over a CSMA-type network having a source for transmitting a source signal comprising a synchronization interval and a data interval and at least one receiver for receiving a second signal having a second synchronization interval and a second data interval corresponding to the data interval of the source signal, comprising: receiver means responsive to the source signal for synchronizing the source within the synchronization interval and providing a retransmit request signal indicative of the source signal; transmitter means responsive to the retransmit request signal for synchronizing at least one receiver within one CSMA time interval delay of the synchronization interval and for transmitting the second data interval to the at least one receiver within one CSMA time interval delay of the source data interval; and interface means for synchronizing the receiver means with the transmitter means to enable data transmission therebetwee

Abstract: There is disclosed a voice/data protocol for use with half duplex digital radios. The protocol modifies the X.21 HDLC protocol which is widely employed in the transmission of data for digital radios. The X.21 protocol utilizes a control "C" and an indicate "I" signal. In the steady state in conventional systems, both the C and the I leads are "off". When either a DTE or DCE requires service, the units set their C lead to the "on" condition. The opposite end detects the request for service on the I lead and when communications occur, sets the C lead to the "on" condition. When both the DTE and DCE have send and detected "on" conditions on their C and I leads the circuit transfers to the data transfer state and is ready to proceed to data synchronization. In the present protocol, the C signal is defined as a push-to-talk transmit request to the radio. The I signal is defined as a radio busy. When the I signal is asserted by the radio, the radio is busy transmitting voice, receiving voice or receiving data.

Abstract: A clip-on power source for powering an ANVIS binocular. The power source has an electrical interface that enables the power source to be detachably coupled to the ANVIS binocular. The interface also enables the power source to pivot relative to the binocular from a first position to a second position to power-on and power-off the ANVIS binocular.

Abstract: There is disclosed an improved multi-mode, spread spectrum digital radio comprising: a radio frequency (RF) subsystem for converting spread spectrum digital signals comprising voice and data communications between baseband and RF signal frequencies in response to control signals; a digital signal processor based baseband subsystem having isolation interface means bidirectionally coupled to the RF subsystem for minimizing RF and baseband signal interference; the baseband subsystem operable to control the mode of operation, to provide interface control signals to the RF subsystem based on the mode, to format the transmitted and received digital signals, and to provide external controls and status to a user to enable selectable mode switching.

Abstract: A method for finding a direction associated with a radiated electromagnetic wave, the method including the steps of: detecting the radiated electromagnetic wave; measuring at least one gain difference and at least one phase difference associated with the detected electromagnetic wave; estimating an elevational angle and an azimuthal angle associated with the detected electromagnetic wave using the at least one measured gain difference; determining a plurality of possible elevational and azimuthal angles associated with the detected electromagnetic wave using the at least one measured phase difference; and, respectively selecting one of the plurality of possible elevational and one of the plurality of possible azimuthal angles as elevational and azimuthal angles associated with the detected electromagnetic wave using the estimated elevational and azimuthal angles.

Abstract: There is disclosed an improved frequency hopping synchronization and tracking system for bit syncing and frame syncing a digital data signal as transmitted by a radio transmitter. A detection means responsive to incoming data samples representative of the phasing signal portion of the digital data signal partitions the data samples into alternating first and second sample sequences and correlates the samples against a frequency hop modulation code reference sequence to provide an initial data signal detection. A post-detection means responsive to the initial detection and to the frequency hop modulation code reference sequence correlates the incoming data samples and compares the spectral power of the correlated data samples to a threshold value to provide bit sync of the detected data signal.

Abstract: There is disclosed a bit sync search and frame sync search system operative with a digital data signal as transmitted by a digital radio transmitter. The bit search is implemented by detecting a predetermined phasing signal which is incorporated in the digital signal and which has a repetitive bit pattern of ones and zeroes. The phasing signal is first detected by providing an in-phase and quadrature component signal and correlating those signals to provide an output signal indicative of the bit pattern in the phasing signal. After the phasing signal has been provided and an oscillator associated with a receiving apparatus is compensated according to the detected phasing signal, a tracking mode is entered, whereby a frame signal is captured and the system generates histograms of data bit transitions for producing an error signal indicative of the difference of the transmitted clock rate and the sampling portion of a received bit.

Abstract: The present invention is directed toward a navigation system and method for a high orbit spacecraft, which passively utilizes UHF signals carrying intersatellite ranging data transmitted by a constellation of satellites that travel in lower orbits around a celestial sphere. The navigation system enables the high orbit spacecraft to self locate its position relative to an earth centered coordinate frame and comprises a receiver for receiving the UHF signal, carrying the intersatellite ranging data and a Kalman or optimum filter coupled to the receiver for processing the ranging data received by the receiver and generating and updating spacecraft position data.

Abstract: A warhead for use in air defense missiles has a flat-sided cross-sectional onfiguration which can be mass focused to direct an entire side onto a target. The warhead may be rotated about the missile longitudinal axis to properly orient a warhead side at the time of detonation.

Abstract: A telescopic sight which can be used for either nighttime or daytime operation and is particularly adaptable for use on weapons ranging from rifles to anti-tank weapons.A first embodiment includes a single objective and two parallel light paths, one for day viewing and one for night viewing. The objective forms the beginning of the night path. Separating mirrors transmit light from the objective along the night path and reflects light from the objective to the day path. The night path includes an image intensifier assembly. A mirror at the end of the night path reflects the light from the image intensifier assembly to a beamsplitter/combiner on the day path. The beamsplitter/combiner transmits the light from the day path and reflects the light from the night path along the same path to an ocular assembly for viewing.A second embodiment of the telescopic sight is similar to the first embodiment but contains two objective lens assemblies for collecting light, one for the night path and one for the day path.

Abstract: A multi-level security apparatus and method for a network employs a secure network interface unit (SNIU) coupled between each host or user computer unit and a network, and a security management (SM) architecture, including a security manager (SM) coupled to the network, for controlling the operation and configuration of the SNIUs coupled to the network. Each SNIU is operative at a session level of interconnection which occurs when a user on the network is identified and a communication session is to commence. When an SNIU is implemented at each computer unit on the network, a global security perimeter is provided. In a preferred embodiment, the SNIU is configured to perform a defined session level protocol (SLP), including the core functions of user interface, session manager, dialog manager, association manager and data sealer, and network interface.