Abstract: The invention relates generally to a roll damping apparatus for a spinning projectile having a first section and a second section rotatably attached about a roll axis. The roll damping apparatus comprises a first portion attached to the front section, and a second portion attached to the rear section. The first portion is adapted to cause a braking frictional force to act on the second portion, the braking force being effective to control the spin rate of the front section relative to the rear section. The invention further relates to a spinning projectile having a roll damping apparatus.

Abstract: The invention provides for a transport system and method of using the transport system. The transport system may include a transport track; and a platform assembly that transports along the transport track, the platform assembly including (1) a cargo platform; and (2) a pair of drive pinion trucks mounted on opposing sides of the cargo platform, each drive pinion truck engaged with the transport track for movement along the transport track. The drive pinion trucks may be provided with a leveling system to provide leveling of the cargo platform during operation.

Abstract: A system for and method of detecting and characterizing materials using entangled photons is presented. The material may be at a great distances from the detector and may be biological material, complex organic compounds, or inorganic chemicals. The disclosed system and method provide advantages over traditional techniques in that they are largely impervious to atmospheric reduction of probing radiation and in that less probing radiation is required. The reduced probe energy requirement allows for detecting and characterizing sensitive material with significantly reduced material bleaching compared with traditional techniques.

Abstract: A method for forwarding incoming cellular communications to an aircraft is provided. A request is received to divert incoming calls for a cellular telephone number to a communication system on board an aircraft. The request includes at least a temporary identification code representing a cellular telephone aboard the aircraft. A diversion instruction is associated with the cellular telephone number. The diversion instruction represents an instruction to forward an incoming call for the cellular telephone number to the communications system aboard the aircraft. A state of a cellular telephone associated with the cellular telephone number is considered as busy, regardless of an actual state of the cellular telephone. An incoming telephone call to the cellular telephone number is forwarded, consistent with said considering and in accordance with the diversion instruction, to the communications system on board the aircraft.

Abstract: A programmable modem (20) for processing a waveform includes a general purpose processor (GPP) engine (34) and special purpose programmable signal processing engines (22) in communication with the GPP engine (34). Each of the special purpose engines (22) executes a special purpose software program (80) to process a portion of the waveform under one of a plurality of communications standards in response to control signals from the GPP engine (34). A power manager engine (56) is in communication with the GPP engine (34) and the signal processing engines (22). The power manager engine (56) responds to the control signals from the GPP engine (34) to power currently used ones of the special purpose engines (22) and to discontinue power to unused ones of the special purpose engines (22). The programmable modem is implemented on a single CMOS integrated circuit (66).

Abstract: A symbol synchronizer (100) is provided for a software-defined communications system (10). The symbol synchronizer (100), when integrated into either a pre- or post-detection diversity signal combiner (108, 208), enables highly accurate signal synchronization with minimal added system complexity. The symbol synchronizer (100) includes a single complex sliding window-matched filter (102) for filtering an input digital signal with a match filtering function based on predetermined signal transfer function characteristics to average out receiver noise from the signal. A signal delay bank (84) includes a plurality of delay blocks each for delaying the digital signal filtered by the single matched filter for a predetermined number of samples. A complex correlator (88) correlates the digital signal filtered by the single complex sliding window matched filter (102) and delayed by the complex correlator (88) with a correlator reference signal, and selects an index of a path having a peak correlator value.

Abstract: A method of determining a distance to an object is presented. A first photon and a second photon are simultaneously generated. The first photon is reflected off an object. The second photon is directed to an optical cavity. An arrival of the first photon is correlated with an arrival of the second photon, and the distance to the object is at least partially determined using the correlation.

Abstract: An embodiment of a method for parameterizing an input signal includes non-linearly transforming the input signal, removing higher order terms by passing the input signal through a low pass filter to produce a linear combination of data symbols and DC components, solving for the DC components, separating a plurality of mixed baseband signals from the input signal, and coordinate transforming each of the separated signals from polar coordinates to Cartesian coordinates. An embodiment of a receiver includes a non-linear transform operator receiving a digitized input signal and adapted to produce a linear combination of data symbols, DC components, and carrier effects; a low-pass filter for removing higher order terms; a separator unit for separating the plurality of mixed baseband signals; and a coordinate transform for converting the separated signals from polar coordinates to Cartesian coordinates.

Abstract: Trajectory is controlled by a control system having fins that de-spin a section of the control system relative to a projectile or missile. The control system also includes aero-surfaces that produce a lift when brought to rotation speed of about 0 Hz relative to a reference fame and a brake that couples the guidance package to the rotational inertia of the projectile or missile. In one example, no electric motor is used in the trajectory control system, saving weight and increasing reliability.

Abstract: A feed assembly (26) for an antenna system (38) includes a first feed element (30) that propagates a first beam (32) and a second feed element (34) that propagates a second beam (36). The second feed element (34) is collocated with, but displaced vertically from, the first feed element (30) to achieve angular diversity in elevation. Each of the feed elements (30, 34) has an elongated conical shape and is formed from a dielectric material. The feed assembly (26) operates within the Ku-band frequency range to yield high gain, collimated, independent first and second beams (32, 34). The feed assembly (26) can be implemented in a tropospheric scatter communication system (38) in conjunction with a reflector (22) to provide concurrent transmit and receive capability via the two independent, angularly separated first and second beams (32, 36).

Abstract: Systems and methods for increasing bandwidth capability of an envelope elimination and restoration (EER) transmitter. A frequency response of a power supply modulator of the transmitter is approximated. An inverse response is applied to the envelope signal prior to digital-to-analog conversion (DAC) and before the signal reaches the power supply modulator to pre-emphasize the signal thereby counteracting distorting affects of the modulator. The filter is implemented using any of a variety of different digital techniques including programmable logic, DSP, etc.

Abstract: A multi-carrier communication system (400) groups subchannels (802) into different quality-of-signal (QoS) regions (804). An unconstrained optimization process (1200) is performed independently for the subchannels (802) of the different QoS regions (804) to allocate bit rates and power to the individual subchannels (802) so that the indicated QoS will result. Coders (504, 508, 512, 516, 1700) partition and error-correction encode source information using encoding schemes matched to the different QoS regions (804). A set (1100) of only a few directed QoS partition vectors (1102) direct the unconstrained optimization process (1200) to attempt bit-rate and power allocations on only a few promising groupings of subchannels (802) and QoS regions (804). An iterative process may take place between bit-rate and power allocation on one side and source information coding on the other for different directed QoS partition vectors (1102) to identify the best solution.

Abstract: A connector is provided. A plurality of parallel pins is mounted in a connector. A circuit board is connected to the connector. Some of the pins are configured to communicate signals from the circuit board and others of the pins are configured to communicate corresponding signal grounds from the circuit board. The pins are organized on the connector such that at least two out of every three of the pins that are configured to communicate signals do not have any neighboring aggressor pins.

Abstract: Provided are two-dimensional autofocus methods in a synthetic aperture radar (SAR) system which include: (1) two-dimensional pulse pair product algorithm including shear PGA, eigenvector phase history (“EPH”), shear PGA/EPH); (2) two-dimensional optimization algorithms including parametric one-dimensional estimate/two-dimensional correction, parametric two dimensional estimate/two-dimensional correction, unconstrained two-dimensional nonparametric and constrained two-dimensional nonparametric methods; (3) a two-dimensional geometry filter algorithm; (4) a two-dimensional prominent point processing algorithm; (5) a one-dimensional phase estimate of higher order two dimensional phase errors; and, (6) a fast SHARP parametric autofocus algorithm.

Abstract: Systems and methods for DC offset correction in analog and digital direct conversion RF receivers. A time derivate and subsequent integration of in-phase and quadrature phase signal path components is performed to effectively remove DC offset from the resultant down converted baseband signal.

Abstract: A system for connecting circuit boards is provided. A plurality of overlapping spaced apart circuit boards have a plurality of conductive pins passing through holes in the circuit boards. A connector includes a flexible sheet insulator and a plurality of conductive surfaces separated and supported by the flexible insulator. At least one of the conductive surfaces has a hole there through and a bent compliant lead extending there from. The hole engages one of the pins, and the complaint lead connects to one of the circuit boards.

Abstract: Methods and apparatus are provided for distributed polyphase spread spectrum communication and non-contiguous spectrum underlay. The method includes polyphase channelizing a direct sequence spread spectrum (DSSS) signal, determining available spectrum in an observed frequency range having a noise floor based on detection of polyphase users below the noise floor, distributing the polyphase channelized signal among the available spectrum, and interference mitigation using a combination of standard signal detection and cyclostationary feature detection methods.

Abstract: In a wireless communication system (20) configured for default communication of subsectional signals of a first transmit signal (72/73) over multiple wireless channels (46), a signal selector (82) and method (138) detect an intent to convey a voice signal (86) over one of the wireless channels (46) from a handset (58). The signal selector (82) and method (138) prevent communication of one of the subsectional signals (72A) over the wireless channel (46) for a predetermined interval, and enable a transmission attempt of the voice signal (86). When a complete dialed digits sequence is detected within the time interval, the handset (58) is enabled to utilize the wireless channel. However, when a transmission attempt of the voice signal (86) is unsuccessful or when transmission of the voice signal (86) terminates, the signal selector (82) and method (138) restore default communication of subsectional signals of the first transmit signal (72/73).

Abstract: An embodiment of the invention generally pertains to a method of compensating for temperature variations in an eddy current sensor signal. The method may include the steps of receiving an initial signal from an eddy current sensor (ECS) in response to a conductive element passing the ECS and sensing an ECS temperature and an ECS board temperature. The method may also include determining a subset of correction coefficients based on the ECS temperature and the ECS board temperature and determining a temperature correction factor from the subset of correction coefficients. The method may then compute a temperature corrected signal from the initial signal and the temperature correction factor.

Abstract: An embodiment of the invention generally relates to a temperature-independent method of determining an engine health parameter, namely stand-off distance, between an eddy current sensor and a conductive element. The method includes receiving a signal from the eddy current sensor and demodulating a waveform from the received signal. The method also includes determining a predetermined set of substantially temperature-independent parameters from the waveform and determining the stand-off distance based on the predetermined set of substantially temperature-independent parameters.