Abstract: The invention provides a communication protocol and serial interface having an approximately fixed interface clock and capable of accommodating a variety of communication rates. The interface employs a variable-length frame that may be expanded or reduced to obtain a desired communication rate, even though the interface clock rate is held approximately constant. The invention further provides a method for designing an agile barrier interface. In particular, the barrier clock rate is preferably selected to be an approximate common multiple of the various communication rates that the barrier interface must handle. The frame length corresponding to each communication rate may then be obtained by dividing the barrier clock rate by the ?? rate. Finally, the invention provides an agile barrier capable of communicating data across a serial interface at a variety of data rates and at an approximately fixed interface clock rate.

Abstract: In a packet-based (e.g., Ethernet) network, such as the network of central offices and base stations of a wireless telephone system, a node receives one or more incoming packet-based signals from one or more other nodes of the network and recovers a clock signal from each incoming packet-based signal. The node selects one of the recovered clock signals as the node's reference clock signal. When the node is part of a base station, the node uses the selected clock to generate and transmit one or more outgoing packet-based signals to one or more central offices. The node also uses the selected clock to generate the base station's wireless transmissions. In one implementation, the base stations and central offices are connected by Ethernet facilities.

Abstract: Embodiments of the present invention generate a normalized floating-point sum from at least two floating-point addends. The mantissa of an un-normalized floating-point sum is generated. A pointer is generated which indicates the location of the left-most significant digit (LSD) in the mantissa of the un-normalized floating-point sum. A plurality of possible values for the exponent of the normalized floating-point sum are generated, in parallel with each other and in parallel with the mantissa addition, based on a common exponent value (e.g., the largest of the two addends' exponent values). Based on the LSD pointer, one of the possible values is selected as the exponent of the normalized floating-point sum. The mantissa of the un-normalized floating-point sum is normalized to yield the mantissa of the normalized floating-point sum. By generating the possible exponent values in parallel, embodiments of the present invention can result in significant time savings over prior-art methods.

Abstract: An optical transmitter having a quantum-well (QW) modulator and a method of operating the same. The QW modulator is configurable to perform both amplitude and phase modulation. Using the disclosed methods, the length of the QW modulator, one or more drive voltages, and/or an operating wavelength can be selected to enable the optical transmitter to generate a modulated optical signal having a relatively high bit rate, e.g., an optical duobinary signal having a bit rate greater than about 80 Gb/s.

Abstract: In one embodiment, a method of monitoring a network. The method includes, at each node of a set, constructing a corresponding vector of M components based on a stream of data packets received at the node during a time period, the set including a plurality of nodes of the network, M being greater than 1; and estimating a value of a byte traffic produced by a part of the packets based on the constructed vectors, the part being the packets received by every node of the set. The constructing includes updating a component of the vector corresponding to one of the nodes in response to the one of the nodes receiving a data packet. The updating includes selecting a component of the vector to be updated by hashing a property of the received data packet.

Abstract: In one embodiment, a mobile station including a chassis having a display, a power reducer, a proximity sensor, and a microprocessor. The power reducer controls power consumption of the display. The proximity sensor is coupled to the chassis and causes the power consumption to be reduced when the display is within a predetermined range of an external object. The microprocessor is coupled to the proximity sensor and to the display and automatically activates the proximity sensor based on the mobile station receiving an incoming wireless telephone call.

Abstract: A structured interleaving/de-interleaving scheme enables efficient implementation of encoding/decoding based on two-dimensional product codes (2D PC). An encoder has an integrated architecture that performs structured interleaving and PC coding in an integrated manner in which locations in the interleaved data stream are related to row and column indices for the 2D PC coding based on closed-form expressions. In one embodiment, a corresponding decoder implements two-stage low-density parity-check (LDPC) decoding based on the same relationships between locations in the interleaved data stream and row and column indices for the LDPC decoding.

Abstract: An audio system generates position-independent auditory scenes using harmonic expansions based on the audio signals generated by a microphone array. In one embodiment, a plurality of audio sensors are mounted on the surface of a sphere. The number and location of the audio sensors on the sphere are designed to enable the audio signals generated by those sensors to be decomposed into a set of eigenbeam outputs. Compensation data corresponding to at least one of the estimated distance and the estimated orientation of the sound source relative to the array are generated from eigenbeam outputs and used to generate an auditory scene. Compensation based on estimated orientation involves steering a beam formed from the eigenbeam outputs in the estimated direction of the sound source to increase direction independence, while compensation based on estimated distance involves frequency compensation of the steered beam to increase distance independence.

Abstract: An input audio signal having an input temporal envelope is converted into an output audio signal having an output temporal envelope. The input temporal envelope of the input audio signal is characterized. The input audio signal is processed to generate a processed audio signal, wherein the processing de-correlates the input audio signal. The processed audio signal is adjusted based on the characterized input temporal envelope to generate the output audio signal, wherein the output temporal envelope substantially matches the input temporal envelope.

Abstract: A generalized hardware architecture that supports built-in self testing (BIST) for a range of different computer memory configurations and a generalized BIST algorithm can be compiled, based on specified configuration characteristics (e.g., the number of write ports, the number of read ports, the number of entries, and the number of bits per entry in the computer memory), to generate the hardware design for a particular computer memory system. In one embodiment, the generalized hardware architecture includes a multiplexer block that enables a single BIST comparator to be multiplexed for use in performing BIST testing via different read ports of the computer memory.

Abstract: In one embodiment, a combined VGA-and-equalizer (VGA-EQ) circuit for a communication link includes a current-mode logic (“CML”) amplifier with an inductive load circuit. The CML amplifier has a gain control terminal and is operable to amplify, with an adjustable gain, a signal received at an input terminal and provide the amplified signal at an output terminal. The CML amplifier has a first gain at frequencies below a predetermined frequency value and a second gain at frequencies in a predetermined frequency range above the predetermined frequency value, wherein the second gain is higher than the first gain. The higher second gain of the VGA-EQ circuit causes a reduction in inter-symbol interference in a signal received by the receiver.

Abstract: A cordless telephone which allows a user to play MP3 digital audio bit stream music, using the remote handset of a cordless telephone to control the functions of the MP3 player. The cordless telephone remains usable as a typical cordless telephone with all the features and conveniences of a cordless telephone including, but not limited to, connection of a telephone call between a calling party and a called party, caller ID information, voice messaging features, etc. MP3 digital audio bit stream music may be downloaded from a remote source through, e.g., the Internet and a PC.

Abstract: Generic and specific C-to-E binaural cue coding (BCC) schemes are described, including those in which one or more of the input channels are transmitted as unmodified channels that are not downmixed at the BCC encoder and not upmixed at the BCC decoder. The specific BCC schemes described include 5-to-2, 6-to-5, 7-to-5, 6.1-to-5.1, 7.1-to-5.1, and 6.2-to-5.1, where “0.1” indicates a single low-frequency effects (LFE) channel and “0.2” indicates two LFE channels.

Abstract: A solar-heating system having an inflatable solar collector connected to a housing that can be installed, e.g., in a sash window of a house. The housing has an air blower that draws air from the interior of the house and directs it into the inflatable solar collector, which is positioned outside the window. The collector has a flexible permeable membrane that serves as a transpired absorber of solar radiation. The air flowing through the collector is heated when it percolates through the membrane exposed to solar light. The heated air is returned back to the interior of the house, thereby providing space heating. In certain embodiments, in addition to serving as a transpired absorber, the membrane can also serve as an air filter that removes particles, odor-causing pollutants, and/or allergens from the drawn air.

Abstract: A seamless transport endpoint mobility (STEM) architecture migrates a transport connection endpoint from an old IP address to a new IP address without loss of the session. The migration process is negotiated between two endpoints themselves. Transport endpoint mobility includes communication between two STEM daemons, one STEM daemon in each endpoint, which dynamically updates kernel data structures (e.g., elements of a 5-tuple associated with a TCP/IP application) associated with the session. Migration is transparent to the application using the underlying transport connection for data transfer.

Abstract: In one embodiment, a method for supporting recovery from failure of a node in a network of nodes interconnected by links A set of two or more intermediate nodes (excluding the failed node) between an ingress point and an egress point is selected. Next, based on available bandwidth of the network, a non-zero fraction of the service level to route from the ingress point to each intermediate node is determined. Packets are then routed in two phases by: (1) determining one or more paths from the ingress point to each intermediate node for routing the corresponding fraction of the service level, and (2) determining one or more paths from each intermediate node to the egress point for routing the corresponding fraction of the service level.

Abstract: According to certain embodiments, integrated circuits are fabricated using brittle low-k dielectric material to reduce undesired capacitances between conductive structures. To avoid permanent damage to such dielectric material, bond pads are fabricated with support structures that shield the dielectric material from destructive forces during wire bonding. In one implementation, the support structure includes a passivation structure between the bond pad and the topmost metallization layer. In another implementation, the support structure includes metal features between the topmost metallization layer and the next-topmost metallization layer. In both cases, the region of the next-topmost metallization layer under the bond pad can have multiple metal lines corresponding to different signal routing paths.

Abstract: Packets are processed (e.g., routed or classified) in accordance with a braided trie, which represents the combination of two or more different original tries (e.g., representing different forwarding/classification tables). The different tries are combined by twisting the mappings for specific trie nodes to make the shapes of the different tries more similar. Each node in the braided trie contains a braiding bit for at least one original trie indicating the mapping for that trie's node. Trie braiding can significantly reduce the number of nodes used to represent the different original tries, thereby reducing memory usage and improving scalability. Braided tries can be used for such applications as virtual routers and packet classification in which different forwarding/classification tables are represented by a single braided trie stored in shared memory.

Abstract: In one embodiment, the invention is a method for modeling electrical behavior of a packaged module having multiple integrated circuits (ICs), such as a multi-chip module (MCM). The method includes: (a) identifying one or more pin groups in the module, wherein a pin group comprises two or more buffers connected together and to a package-external pin, and (b) generating one or more corresponding unified behavioral models for the one or more pin groups based on the characteristics of the buffers of the one or more pin groups. The behavioral models are part of an integrated behavioral model file in accordance with the I/O buffer information specification (IBIS) standard.

Abstract: In one embodiment, the present invention is a method for reducing the peak-to-average power ratio (PAPR) of a multi-carrier modulated symbol, such as an orthogonal frequency division multiplexed (OFDM) symbol. The method first transforms a set of data symbols into a multi-carrier modulated symbol. The method then uses the multi-carrier modulated symbol and a gradient-descent algorithm to generate a set of symbols for PAPR-reduction tones. The data symbols and the PAPR-reduction symbols are then transformed to generate an updated multi-carrier modulated symbol. The PAPR-reduction symbols are iteratively updated until a terminating condition occurs (e.g., an acceptable PAPR is achieved for the multi-carrier modulated symbol).