GENERAL DYNAMICS C4 SYSTEMS, INC. Patent applications |
Patent application number | Title | Published |
20130336432 | METHODS AND SYSTEMS FOR PROCESSING A DIGITAL SIGNAL BY ESTIMATING SIGNAL ENERGY AND NOISE POWER DENSITY - Systems and methods are described for processing a digital signal. In one embodiment, the method comprises receiving time-aligned input samples of an input signal; computing at least one moment using the time-aligned input samples; determining at least one of signal energy per symbol and noise power spectral density based on the at least one moment; and adjusting an input signal level based on the at least one of the signal energy per symbol and the noise power spectral density. | 12-19-2013 |
20130314289 | PHASE SHIFT DEVICE AND METHOD - A phase shift device includes an input quadrature junction for receiving an input EM signal and extracting a first electromagnetic (EM) signal, a second EM signal, a third EM signal, and a fourth EM signal from the input EM signal. Four waveguide arms are operatively connected to the input quadrature junction for respectively conveying the first, second, third, and fourth EM signals therethrough. At least two of the waveguide arms shift the phase of EM signal conveyed therethrough such that two of the first, second, third, and fourth EM signals are phase shifted with respect to the other two of the first, second, third, and fourth EM signals. An output quadrature junction is operatively connected to the waveguide arms for combining the first, second, third, and fourth EM signals. Thus, polarization adjustment may be achieved through rotation of the phase shift device. | 11-28-2013 |
20120225683 | CHANNEL SELECTION IN A WIRELESS NETWORK - Systems and methods are described for managing channel selection among a plurality of mesh points in a wireless network. In one embodiment, a method includes receiving a first announcement that includes channel exclusion information from a first mesh point; managing a distributed channel exclusion list based on the announcement; and generating a second announcement to the first mesh point based on the channel exclusion list. | 09-06-2012 |
20120216036 | ENCRYPTION METHODS AND SYSTEMS - Systems and methods are described for securely transmitting data in a mesh network. The method includes: performing on a processor, assembling a header with a recipient address, wherein the recipient address designates an encryption endpoint; associating encrypted data with the header; and presenting a packet for transmittal on the mesh network, wherein the packet includes the header and the encrypted data. | 08-23-2012 |
20120170468 | POWER MANAGEMENT IN A WIRELESS AD HOC NETWORK - In a wireless ad hoc network ( | 07-05-2012 |
20120121003 | METHODS AND APPARATUS FOR WIRELESSLY COMMUNICATING SIGNALS THAT INCLUDE EMBEDDED SYNCHRONIZATION/PILOT SEQUENCES - An embodiment for wirelessly communicating a signal includes a transmitter combining a plurality of phase shifted input data signals with a plurality of synchronization/pilot sequences to produce a plurality of combined signals, performing frequency domain-to-time domain transformations of the combined signals to produce a plurality of candidate signals, determining peak-to-average ratios for at least some of the plurality of candidate signals, identifying a selected signal from the plurality of candidate signals based on the peak-to-average ratios, and transmitting the selected signal over a wireless communication channel. An embodiment further includes a receiver receiving a channel-affected version of the transmitted, selected signal, determining an estimate of a selective mapping index, which identifies the synchronization/pilot sequence from the plurality of synchronization/pilot sequences, applying corrections to the received signal based on estimated channel perturbations to produce an equalized combined signal, and producing an output data symbol from the equalized combined signal. | 05-17-2012 |
20110235762 | SYMBOL TIMING SYNCHRONIZATION METHODS AND APPARATUS - Embodiments include methods and apparatus for performing symbol timing synchronization for a symbol-bearing signal. The symbol-bearing signal is sampled to produce a plurality of symbol samples. First-direction interpolation processes are performed on the plurality of symbol samples in a first temporal direction, where the first temporal direction is a direction from a first sampling time towards a second sampling time. In addition, second-direction interpolation processes are performed on the symbol samples in a second temporal direction, where the second temporal direction is a direction from the second sampling time towards the first sampling time, resulting in a set of interpolated symbol samples. | 09-29-2011 |
20110213984 | SERIAL ARCHITECTURE FOR HIGH ASSURANCE PROCESSING - A processing system ( | 09-01-2011 |
20110149929 | METHODS AND APPARATUS FOR MULTIPLE-ANTENNA COMMUNICATION OF WIRELESS SIGNALS WITH EMBEDDED PILOT SIGNALS - Embodiments of methods and apparatus for wirelessly communicating signals include one or more transmitters configured to generate a plurality of wireless signal for transmission. Each of the wireless signals includes a plurality of pilot signals represented in a plurality of unevenly spaced, in-band subcarriers. Pilot signals of each wireless signal are positioned at subcarriers that are orthogonal in frequency with subcarriers at which pilot signals of all other wireless signals are positioned. According to an embodiment, subcarrier indices each the plurality of pilot signals are determined using a third order or higher order polynomial parameterization of pilot subcarriers in conjunction with a convex optimization algorithm to produce pilot signals having near-optimal channel estimate mean square error (MSE) performance. The wireless signals are simultaneously radiated over a wireless communication channel using a plurality of co-located or distributed antennas. | 06-23-2011 |
20110116386 | TRANSMISSION CONTROL IN A WIRELESS COMMUNICATION SYSTEM - In a communication system that includes a control terminal (CT), a relay apparatus (RA), and a plurality user equipment (UE) that wirelessly communicate with the CT through the RA, a method for performing transmission control includes the CT receiving an RA-CT downlink signal that originated from a UE, determining a frequency-of-arrival (FoA) error from the RA-CT downlink signal (where the FoA error results at least in part from an error in a UE time reference with respect to a CT time reference), and providing, to the UE, a transmit frequency control (TFC) feedback signal that indicates the error in the UE time reference. The UE produces an adjusted UE uplink carrier frequency signal that compensates for the error in the UE time reference as indicated in the TFC feedback signal, and upconverts and transmits a UE-RA uplink signal using the adjusted UE uplink carrier frequency signal. | 05-19-2011 |
20110103578 | SYSTEMS AND METHODS FOR EFFICIENTLY CREATING DIGESTS OF DIGITAL DATA - Systems and methods efficiently process digests, hashes or other results by performing multiplicative functions in parallel with each other. In various embodiments, successive processing stages are provided, with each stage performing parallel multiplicative functions and also combining input terms to reduce the total number of terms that remain to be processed. By progressively combining the active terms into a smaller number of terms for subsequent processing, the time needed to process a result can be significantly reduced. | 05-05-2011 |
20110085297 | Self Releasing Hinge - The exemplary embodiments describe a device, such as a laptop computer, having a base assembly and a display panel joined by a hinge mechanism that allows for the display panel to rotate in either a clockwise or counterclockwise direction and pivot with respect to the base assembly. | 04-14-2011 |
20110075745 | REDUCING TRANSMITTER-TO-RECEIVER NON-LINEAR DISTORTION AT A TRANSMITTER PRIOR TO ESTIMATING AND CANCELLING KNOWN NON-LINEAR DISTORTION AT A RECEIVER - A communication system is provided that includes a transmitter device and a receiver device. The transmitter device transmits input data as a transmitted signal having the known non-linear distortion (NLD) characteristic. The receiver receives a received signal that represents a channel affected version of the transmitted signal and that has the known NLD characteristic. The received signal includes power amplifier distortion (PAD) induced by the transmitter device's power amplifier. The receiver is designed to iteratively estimate, based on the known NLD characteristic, remaining PAD caused by the power amplifier, and to iteratively cancel estimated PAD to reduce PAD in the received signal. | 03-31-2011 |
20110074506 | CANCELLING NON-LINEAR POWER AMPLIFIER INDUCED DISTORTION FROM A RECEIVED SIGNAL BY MOVING INCORRECTLY ESTIMATED CONSTELLATION POINTS - A method and system are provided for reducing power amplifier induced distortion. Power amplifier induced distortion is iteratively estimated and cancelled. When the difference between the current estimated power amplifier distortion and the previous estimated power amplifier distortion is less than a convergence threshold, particular M-QAM constellation points that are still in error are determined A M-QAM constellation point correction routine is provided that can move the incorrectly estimated M-QAM constellation points that are in error towards their expected quadrants by generating updated M-QAM constellation points. The remaining estimated non-linear power amplifier induced distortion in the received signal can then be estimated and canceled. | 03-31-2011 |
20110008986 | USB Receptacle and Plug Connecting Device - A USB connection device that is capable of holding a USB receptacle and a USB plug, where the USB receptacle and USB plug are capable of mating inside the USB connection device. In some embodiments, the USB connection device comprises a housing having an upper wall, a lower wall, two side walls, at least one open side, and a protruding lever. The upper wall and the bottom wall have interior surfaces with a plurality of ridges and a plurality of slanted ridge walls capable of compressing a plurality of spring arms on a USB receptacle. The upper and bottom walls also have a plurality of pockets that allow the spring arms to de-compress. The device is capable of moving from side-to-side when a force is applied to the protruding lever, and the device is capable of retaining the USB receptacle and a mated USB plug during the side-to-side movement. | 01-13-2011 |
20100215174 | RELIABLE ELLIPTIC CURVE CRYPTOGRAPHY COMPUTATION - A method for reliable computation of point additions and point multiplications in an elliptic curve cryptography (ECC) system. Two asymmetric operations are performed: one of the operations is of slightly higher complexity than a conventional ECC operation, and the other operation is of much lower complexity than the first operation. The complexity of the second operation is a function of the desired degree of reliability, or the desired probability of failure detection. The method validates a computation involving one or more points on a specified elliptic curve by selecting a second elliptic curve, deriving a third elliptic curve from the specified and selected curves, projecting points onto the derived curve, performing a computation on the derived curve involving the projected points, validating the computation on the selected curve, extracting from the computation on the derived curve a predicted result of the computation on the selected curve, and comparing the predicted result to the computation on the selected curve. A predicted result of the computation to be validated may then be extracted from the computation on the derived curve. The predicted result is compared to an actual result of a computation on the selected curve, and if the results match, the predicted result of the computation performed on the selected curve is validated. | 08-26-2010 |
20100192159 | SEPARATION KERNEL WITH MEMORY ALLOCATION, REMOTE PROCEDURE CALL AND EXCEPTION HANDLING MECHANISMS - A computer-implemented system ( | 07-29-2010 |
20100192154 | SEPARATION KERNEL WITH MEMORY ALLOCATION, REMOTE PROCEDURE CALL AND EXCEPTION HANDLING MECHANISMS - A computer-implemented system ( | 07-29-2010 |
20100172427 | METHODS AND APPARATUS FOR MULTIPLE-ANTENNA COMMUNICATION OF WIRELESS SIGNALS WITH EMBEDDED SYNCHRONIZATION/PILOT SEQUENCES - Embodiments include methods for determining synchronization/pilot sequences (SPS) to be utilized in conjunction with transmissions by antennas of a multiple-antenna transmitter. The SPS include pilot signals that are positioned at subcarriers that are orthogonal in frequency with subcarriers at which pilot signals of other antennas are positioned. The pilot signals may be unevenly spaced across the in-band subcarriers. The multiple-antenna transmit system generates a plurality of wireless signals, each of which may include an SPS having synchronization information in a first plurality of in-band subcarriers and the pilot signals in a second plurality of in-band subcarriers. The wireless signals are simultaneously radiated over a wireless communication channel using a different antenna. A receiver receives channel-affected versions of the wireless signals, and produces a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal. | 07-08-2010 |
20100142592 | METHOD AND APPARATUS WITH NOTCHED TRANSMIT FREQUENCY BINS - A wireless network ( | 06-10-2010 |
20100128642 | METHODS AND APPARATUS FOR SUPPORTING A HALF-DUPLEX MODE OF OPERATION FOR USER EQUIPMENT COMMUNICATIONS IN A RADIO COMMUNICATION SYSTEM - Embodiments include methods performed in time division duplex (TDD) radio communication systems in which information is communicated between a first node (e.g., a base) and a second node (e.g., user equipment) in a context of a data frame that includes a plurality of slots. The second node applies an adjustment to an alignment between a second node transmit clock and a second node receive clock based on a propagation delay between the first node and the second node. The adjusted alignment ensures that second node receive slots and second node transmit slots are non-overlapping with each other in time, and that the second node will operate in a half-duplex mode of operation. The second node transmits a transmit burst during the second node transmit slots, and receives a first node transmit burst from the first node during the second node receive slots. | 05-27-2010 |
20100125739 | SECURE CONFIGURATION OF PROGRAMMABLE LOGIC DEVICE - A cryptographic system ( | 05-20-2010 |
20100080211 | METHODS AND APPARATUS FOR COMMUNICATING INTERNET PROTOCOL BASED CONTROL SIGNALING THROUGH A COMMUNICATIONS SYSTEM - An embodiment of a method for communicating call control signaling information in a communications system that includes a user equipment (UE) and a base includes the UE formatting the call control signaling information, transmitting the call control signaling information over a first logical channel that is mapped to a first transport channel, and transmitting user traffic over a second logical channel that is mapped to a second transport channel. In an embodiment, the base receives the call control signaling information from the UE over the first logical channel, receives the user traffic from the UE over the second logical channel, and transmits the call control signaling information to a core network. In an embodiment, the communication system is an IP network in which information is exchanged between the UE and the base using a W-CDMA transmission protocol. The base may form a portion of a satellite-based radio network. | 04-01-2010 |
20100039983 | PROVIDING SERVICE IN A SATELLITE COMMUNICATIONS SYSTEM TO DISADVANTAGED TERMINALS - A base station ( | 02-18-2010 |
20100013735 | DUAL FREQUENCY ANTENNA SYSTEM - A dual-frequency conformal multi-filiar helical antenna system ( | 01-21-2010 |
20090219915 | DISTRIBUTED REQUEST QUEUE FOR A DATA COMMUNICATION SYSTEM, AND RELATED OPERATING METHODS - A user equipment (UE) device and associated operating techniques can be utilized to manage the queuing of network service requests in a distributed manner throughout a data communication system. The request queuing methodology leverages request queues maintained at UE devices within the system. An embodiment of a UE device that supports such request queuing includes a processor and a request queue coupled to the processor. The request queue is configured to queue one or more requests for network resources as instructed by the processor, resulting in one or more held requests. The UE device also includes a receiver element coupled to the processor. The receiver element is configured to receive a notification from the network communication component, where, in response to receiving the notification, the processor prepares the one or more held requests for transmission to the network communication component at different times. | 09-03-2009 |
20090213782 | RANDOM ACCESS SLOT SELECTION IN A COMMUNICATIONS SYSTEM - A communications system ( | 08-27-2009 |
20090207854 | SYSTEMS AND METHODS FOR PROVIDING EFFICIENT BANDWIDTH UTILIZATION IN PACKET SWITCHED NETWORKS - Systems and methods are described for efficiently transmitting packetized data from a sender to a receiver over a communications link. A compression context is established between the sender and the receiver based upon commonalities in each of the data packets prior to transmitting the data over the communications link. The data is compressed according to the compression context to thereby create compressed data packets, and the compressed data packets are transmitted to the receiver across the communications link. By establishing compression contexts prior to transmission, the need for in-band signaling is reduced or eliminated. | 08-20-2009 |
20090059917 | SYSTEMS AND METHODS FOR RELIABLE MESSAGE DELIVERY OVER DIGITAL NETWORKS - Systems and methods reliably transmit a message from a sender to a receiver via a network. A reliability module is configured to determine a probability of delivering a packet from the sender to the recipient via the network. Mode selection logic determines transmission mode from a number of options based upon the probability of delivering the packet from the sender to the recipient. A formatting module is configured to provide a first push that includes the message and, in at least one of the operating modes, a number of redundancy packets formulated as a function of the contents of the message. The receiver acknowledges the packets received so that any dropped packets can be re-transmitted. The redundancy packets can be created using Reed-Solomon or other forward error-correcting codes to further increase the reliability of the message transmission when network conditions warrant. | 03-05-2009 |
20090052561 | METHODS AND APPARATUS FOR GENERATING AND COMMUNICATING WIRELESS SIGNALS HAVING PILOT SIGNALS WITH VARIABLE PILOT SIGNAL PARAMETERS - An embodiment for wirelessly communicating a signal includes a transmitter generating and transmitting a wireless signal over a wireless communication channel. The wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers. In an embodiment, the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots. An embodiment further includes a receiver receiving a channel-affected version of the wireless signal, and producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, where the estimated channel perturbations are determined based on the plurality of pilot signals. The receiver also produces an output data symbol from the corrected signal. | 02-26-2009 |
20090028064 | METHOD AND SYSTEM FOR CAPACITY ANALYSIS FOR ON THE MOVE ADHOC WIRELESS PACKET-SWITCHED NETWORKS - A system and method for capacity analysis in communication networks, particularly for on the move ad hoc wireless packet-switched networks, as well as wide variety of other multimedia networks is disclosed. The invention seeks to use the same two attributes per link (link capacity and link utilization) as known circuit-switched based analysis tools while incorporating useful aspects of various statistical analyses, such as a Queuing Theory based analysis, among others. In one embodiment, the invention introduces four tests to be implemented per each link, with results of these four tests being used to color code link congestion states to generate the reports for a planner. These four tests may generate an improved analysis of the network utilizing the same number of variables used in simple conventional circuit switched based analysis. | 01-29-2009 |
20090011722 | METHODS AND APPARATUS FOR WIRELESSLY COMMUNICATING SIGNALS THAT INCLUDE EMBEDDED SYNCHRONIZATION/PILOT SEQUENCES - An embodiment for wirelessly communicating a signal includes a transmitter combining a plurality of phase shifted input data signals with a plurality of synchronization/pilot sequences to produce a plurality of combined signals, performing frequency domain-to-time domain transformations of the combined signals to produce a plurality of candidate signals, determining peak-to-average ratios for at least some of the plurality of candidate signals, identifying a selected signal from the plurality of candidate signals based on the peak-to-average ratios, and transmitting the selected signal over a wireless communication channel. An embodiment further includes a receiver receiving a channel-affected version of the transmitted, selected signal, determining an estimate of a selective mapping index, which identifies the synchronization/pilot sequence from the plurality of synchronization/pilot sequences, applying corrections to the received signal based on estimated channel perturbations to produce an equalized combined signal, and producing an output data symbol from the equalized combined signal. | 01-08-2009 |
20090003308 | METHODS AND APPARATUS FOR GENERATING SYNCHRONIZATION/PILOT SEQUENCES FOR EMBEDDING IN WIRELESS SIGNALS - An embodiment includes a method for generating a set of synchronization/pilot sequences (SPS) by generating a plurality of candidate SPS using different initial conditions. Correlations are performed among the candidate SPS to generate a plurality of correlation values, and a plurality of permutations of the candidate SPS are determined, where each permutation includes a different set of candidate SPS, and wherein each permutation includes a number, D, of candidate SPS. In addition a selected permutation is identified from the plurality of permutations, where the selected permutation corresponds to the set of SPS being generated. A system includes a transmitter adapted to generate a wireless signal in which an SPS is embedded by combining each SPS of the set with phase shifted input data, determining peak-to-average power ratios (PARs) for at least some of the combined signals, and identifying a selected combined signal based on the PARs. | 01-01-2009 |