Abstract: A processing system (60) includes an input interface (62), a first processor (64), a second processor (66), and an output interface (68) arranged in a serial configuration. Each of the input interface (62), first processor (64), second processor (66), and output interface (68) computes a digest (92, 100, 110, and 114) using information, e.g., a unique parameter (94, 102, 112, 118), known only by that element (62, 64, 66, 68) and using information generated by that element (62, 64, 66, 68). The digests (92, 100, 110, and 114) are used to validate the integrity of payload data (86) processed by the system (60) to form processed data (104) and the system (60) only outputs the processed data (104) upon validation of data integrity. The serial configuration of system (60) may be implemented to provide high bit rate, redundant cryptographic services.

Abstract: A communication system and receiver is provided that facilitates increased message size in a communication system that supports a large number of transmitters sharing a common frequency band. The communication system facilitates increased message size by incorporating a plurality of transmit bit sets in each burst of data. The additional transmit bit sets are incorporated into a plurality of transmit codes that are generated using at least one additional spreading code that is orthogonal to the base spreading code. The plurality of transmit codes are then combined into one composite message and the composite message is spread again using another scrambling sequence. The final composite spread message is transmitted to the receiver in the appropriate message time slot, resulting in CDM/TDMA burst signal that facilitates increased message size.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Embodiments include methods and apparatus for verifying the detection of a correlation peak, which may represent an acquisition of a received acquisition code symbol sequence. The method includes determining a series of coherently-aligned peaks from a series of correlation peaks. Determining the plurality of coherently-aligned peaks includes correcting a frequency offset and a phase offset for each of the plurality of correlation peaks. A coherent match filter process is performed on the plurality of coherently-aligned peaks. A detection of the correlation peak may be verified when the match filter result exceeds a threshold.

Abstract: 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.

Abstract: A method for managing operability of an on-chip debug capability (24) in a product (26) configured to execute software (30) includes storing (74, 76) a debug public key (40) and an operational public key (44) in product memory (54). The software (30) with either a debug signature (82) or an operational signature (88) is saved (84) in the memory (56). When enablement indication is received, the debug signature (82) is validated (102) using the debug public key (40). The debug capability (24) is enabled upon validation of the signature (82) and the software (30) is allowed to execute. When disablement indication is received, the operational signature (88) is verified (112) using the operational public key (44). The on-chip debug capability (24) is disabled upon verification of the signature (88) and the software (30) is allowed to execute.

Abstract: A dual-frequency conformal multi-filiar helical antenna system (20) provides a low-profile, low drag antenna useable in flying equipment. This antenna system (20) securely holds within its shell (22) signal distribution circuitry (64), signal combining circuitry (68), and any other circuit components necessary for antenna system (20) to communicate with other stations or devices. Antenna system (20) has radiating conductors (24, 32) tuned to two different frequencies such that simultaneous transmission and reception of signals is possible in the same and opposite directions.

Abstract: A base station (26) provides service in a satellite communications (SATCOM) system (22) to a terminal (24). The SATCOM system (22) operates in accordance with a first standard (43), and the terminal (24) is unable to communicate in accordance with the first standard (43). Methodology entails receiving, at a SATCOM resource controller (32), a request (62) for a satellite resource (46) from the base station (26). The satellite resource (46) is allocated to the base station (26) and the controller (32) sends a message (58) with the allocated satellite resource (46). The base station (26) applies a second standard (48), defining a specific set of functional and performance characteristics, to the satellite resource (46). The terminal (24) is enabled to perform satellite communications in accordance with the second standard (48) using the satellite resource (46).

Abstract: A communication network (22) includes a central node (30) loaded with a trusted key (26) and key material (56) corresponding to an asymmetric key agreement protocol (48). The network (22) further includes vulnerable nodes (32) loaded with key material (69) corresponding to the protocol (48). Successive secure connections (68, 70) are established between the central node (30) and the vulnerable nodes (32) using the key material (56, 69) to generate a distinct session key (52) for each of the secure connections (68, 70). The trusted key (26) and one of the session keys (52) are utilized to produce a mission key (39). The mission key (39) is transferred from the central node (30) to each of the vulnerable nodes (32) via each of the secure connections (68, 70) using the corresponding current session key (52). The mission key (39) functions for secure communication within the communication network (22).

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 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.

Abstract: A computer-implemented system (90) is provided that supports a high degree of separation between processing elements. The computer-implemented system (90) comprises a plurality of cells (92) residing on the computer-implemented system, where each cell (92) includes a domain of execution (94) and at least one processing element (96); a separation specification (99) that governs communication between the processing elements (96); and a kernel (98) of an operating system that facilitates execution of the processing elements (96) and administers the communication between the processing elements (96) in accordance with the separation specification (99), such that one processing element (96) can influence the operation of another processing element (96) only as set forth by the separation specification (99). In particular, the separation specification provides memory allocation, remote procedure calls and exception handling mechanisms.

Abstract: A computer-implemented system (90) is provided that supports a high degree of separation between processing elements. The computer-implemented system (90) comprises a plurality of cells (92) residing on the computer-implemented system, where each cell (92) includes a domain of execution (94) and at least one processing element (96); a separation specification (99) that governs communication between the processing elements (96); and a kernel (98) of an operating system that facilitates execution of the processing elements (96) and administers the communication between the processing elements (96) in accordance with the separation specification (99), such that one processing element (96) can influence the operation of another processing element (96) only as set forth by the separation specification (99). In particular, the separation specification provides memory allocation, remote procedure calls and exception handling mechanisms.

Abstract: 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.

Abstract: Methods and apparatus are provided for secure communication techniques in a communication system. The system can include a first device which communicates with a second device over a channel. A security association can be established during a first session between the devices via an asymmetric key exchange. The security association comprises a Traffic Encryption Key (TEK) and a first state vector. The TEK comprises a shared, secret symmetric key. The security association is stored in each of the devices for use during a second session between the devices to expedite security association establishment during call set-up of the second session. The security association can be associated with the second device in the first device, and with the first device in the second device. An updated state vector can be generated at the first device. A second session can be established between the first device and the second device by using the TEKs from the first session and the updated state vector.