Abstract: 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.

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: 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.

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: 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.

Abstract: A wireless network (20) with at least a first radio communication unit (24) and a second radio communication unit (26) transmits and receives signals with minimal interference from the surrounding environment of the first unit (24) and second unit (26). The first radio communication unit (24) determines frequencies (54) having power level above a threshold (52), and creates a list of these frequencies (50) to be transmitted to the second radio communication unit (26). The second radio communication unit (26) places notches (140) in its transmission band (88) based on frequencies (54) in the list (50), reserved frequencies (132), and local frequencies (92) having signal energy above a threshold (90). When transmitting a signal (42), the second radio communication unit (26) avoids transmitting in frequencies that have notches (140).

Abstract: 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.

Abstract: A method (104), operable on a processor platform (24), and a code module (38) facilitate navigation between webpages (34) of a website (32). The code module (38) is incorporated into the webpages (34), and is executed at the processor platform (24) when one of the webpages (34) is downloaded to the processor platform (24). Upon execution of the code module (38), a destination address (36) for the downloaded webpage (34) is obtained. When one or more keywords are detected in the destination address (36), a thread of navigation links (124) related to the keywords is generated and displayed within the current website. The navigation links (124) reference other webpages (34) of the website (32) pertinent to the current webpage (34), and these other webpages (34) can be downloaded when their associated navigation links (124) are activated.

Abstract: In a wireless ad hoc network (20) of nodes (22), a method (64) of power management entails monitoring (82) a current traffic load of the network (20), and in response to the current traffic load, selecting (106, 132) a subset (102) of epochs (80) within cyclically repeating time windows (78) for network communication. A message (122) is communicated (120) between the nodes (22) in the network (20). The message (122) identifies the subset (102) of epochs (80) for using in communicating network traffic (32). Following receipt of the message, each of the nodes (22) modifies (124) a transmit capability mode by entering a run state (40) during the epochs (80) within the subset (102) to enable communication of network traffic (32) and by entering a low power consumption idle state (42) during the remaining epochs (80) within the time window (78).

Abstract: 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.

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: In an embodiment, a receiver includes an antenna configured to receive a communication frame. The communication frame may include an acquisition code symbol sequence, which in turn may include a plurality of acquisition code symbols. In an embodiment, an acquisition code symbol includes a subcode sequence having a plurality of subcodes. A receiver also may include a correlation calculator coupled to the antenna. The correlation calculator may be configured to determine a correlation between the subcodes of the received communication frame and a stored version of the subcodes. The correlation may be used in determining a timing offset for further processing of the communication frame.

Abstract: 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.

Abstract: 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.

Abstract: A communications system (20) includes a resource controller (22) and a terminal (24) in communication with the resource controller (22). Periodically, the resource controller (22) sends a service announcement (46) that identifies a set (50) of timeslots (52) within a communication resource (40) configured for random access within a future frame (42). The terminal (24) ascertains a burst characteristic (118) of a message (54) to be sent from the terminal (24) and generates a random access parameter (128). The terminal (24) selects one of the timeslots (52) from the set (50) in accordance with the random access parameter (128), the timeslot exhibiting a burst type (62) corresponding to the burst characteristic (118) of the message (54). The terminal (24) transmits the message (54) in the selected timeslot (52).

Abstract: A cryptographic system (100) and methodology executable within the cryptographic system (100) enable the use of a programmable logic device PLD (108) in a single chip cryptographic design flow for secure cryptographic services. Methodology for secure configuration of the PLD (108) within a cryptographic system 100 entails secure configuration and authentication (202), functional verification (204), configuration key reload capability (206), traffic key load capability (208) using a split key technique, isolation between command and key fill domains for secure key fill (210) of key material, redundant system instantiation (212), and high speed comparison for secure operation.

Abstract: 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.

Abstract: A programmable electronic device (10) stores a number of cipher-text software modules (14) to which access is granted after evaluating a user's token (55, 80, 82), a software-restriction class (58) for a requested software module (14), and/or a currently active access-control model (60). Access-control models (60) span a range from uncontrolled to highly restrictive. Models (60) become automatically activated and deactivated as users are added to and deleted from the device (10). A virtual internal user proxy that does not require users to provide tokens (80, 82) is used to enable access to modules (16) classified in a global software-restriction class (62) or when an uncontrolled-access-control model (68) is active. Both licensed modules (76) and unlicensed modules (18,78) may be loaded in the device (10). However, no keys are provided to enable decryption of unlicensed modules (18,78).

Abstract: 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.

Abstract: 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.