Abstract: Included are embodiments for sending data in an environment with a plurality of protocols. At least one embodiment of a method includes receiving, at a communications device, an indication to send first data to an access point in a first communications protocol and determining that second data is being communicated in a second communications protocol. Some embodiments include determining a period of silence from data communication in the second communications protocol and sending the first data in the first communications protocol during the period of silence.

Abstract: A system for isolating individual channels in a broadcast signal is provided. The system includes a plurality of multipliers, each having an input and an output. A summer coupled to the outputs of each of the plurality of multipliers is provided to generate an output. A multiplication factor system provides a multiplication factor to each of the multipliers to select a predetermined frequency channel of the input signal.

Abstract: In today's environment class-D amplifiers are used to provide an integrated solution for applications such as powered audio devices due to their advantages in power consumption and size over more traditional analog amplifiers. Due to power output requirements, the output stages of power drivers such as class-D amplifiers require a supply voltage in excess of the technologically allowed voltage for the switches in the output stage. A level shifter is used to ensure voltages supplied to the output switches do not exceed the technological limits. An ideal level shifter should provide the optimal voltage swing to output switches under all process, supply voltage and temperature (PVT) variations. The ideal level shifter should also provide fast transitions when the control signal changes from high to low and low to high.

Abstract: A methods and apparatus for remote management of switching network nodes in a stack via in-band messaging are presented. Switching nodes in the stack default to reserved switching node identifiers and stacking ports default to a blocking state upon startup, restart, and reset. Each command frame received via a blocking state is forwarded to a command engine at each switching node and is acknowledged with the current switching node identifier. Each acknowledgement frame bearing the reserved network node identifier triggers configuration of the acknowledging switching node. Switching nodes and the management processor track interrupt state vectors regarding events. An interrupt acknowledgement process is employed to track raised interrupts. Configuration of switching node is performed via command frames transmitted by the management processor and destined to a command engine associated with the switching node.

Abstract: Laser printers are plagued with an assortment of alignment issues. In color laser printers the issues are exacerbated. Variations in distance from the mirror to the drum can lines in different color planes to vary in size. Variations in angles in the facets of the mirror can cause alignment issues between lines. Even lack of synchronization between the dot clock and start of line indication can cause misalignment between rows. In addition, a cosine distortion occurs due to the non-constant linear velocity of the laser scan of a single line. A very high speed master clock can drive the laser scanning unit. By using a very high speed clock, the control circuitry has the resolution to compensate for many of these distortion types, by appropriately counting clock cycles and indicating such to the laser modulator.

Abstract: Class-D amplifiers have evolved from using binary pulse-width modulation (PWM) modulators to three-level PWM modulators. Three-level PWM drivers for audio applications offer the benefits of eliminating costly elements at the output of an audio system. However, they also introduce increased common-mode interference. Three-level PWM generates three states, but one state has two interchangeable representations which can be scrambled in order to shape the common-mode output spectrum.

Abstract: A processor is provided that includes a primary memory and color conversion logic. The primary memory may store a first color look-up table (LUT) related to a second color space. The color conversion logic, in response to a received set of pixels having color values in a first color space, converts the received set of pixels to a second color space. The color conversion logic selectively accesses, based on a comparison of one or more pixel parameters to a threshold, one of the primary memory and a secondary memory located on a second device to obtain a color value of the second color space that is associated with each pixel of the set of pixels. The color conversion logic monitors the number of times that each of the primary memory and the secondary memory are accessed and automatically adjusts the threshold to maintain an access ratio.

Abstract: A system is described for encryption and decryption of digital data prior to the digital data entering the memory of a digital device by generating a key, sub-key and combining the sub-key with mixed digital data, where the encryption and decryption occurs between the memory controller and the input output register.

Abstract: Poly-phase filters are used to offer an efficient and low complexity solution to rate conversion. However, they suffer from inflexibility and are not easily reconfigured. A novel design for rate converters employ poly-phase filters but utilize interpolation between filter coefficients to add flexibility to rate conversion. This interpolation can be implemented as an interpolation of the poly-phase filter results. Additional approximations can be made to further reduce the amount of calculations required to implement a flexible rate converter.

Abstract: Systems and methods for providing bias currents to multiple analog circuits are disclosed. An integrated circuit comprises a calibration circuit which compares a high tolerance external component to a plurality of internal components manufactured to span the variability of the process, voltage and temperature. The best fitting internal component is communicated to bias circuits which can select an internal component from a local plurality of internal components with matching desired characteristics. In this manner, analog circuits can be locally biased with the tolerance usually associated with a high tolerance external reference component, without the necessity for a local external reference component.

Abstract: The invention relates to a demodulator circuit in a communication system using a multi-carrier modulation scheme. The demodulator uses channel state information for respective carriers in the multi-carrier modulation to de-map the received data.

Abstract: A modem for use with a computer having a demodulator and a decoder, the modem comprises a hardware interface; a demodulator front-end having a first input and a first output, the first output of the demodulator front-end being configured to interface with the demodulator of the computer and to provide a demodulated front-end signal to the demodulator over the hardware interface; and a forward error correction (FEC) unit having a second input and a second output, the second input of the FEC unit being configured to interface with the demodulator of the computer and to receive a demodulated signal from the demodulator over the hardware interface, the demodulated signal being a demodulation of the demodulated front-end signal, and the second output of the FEC unit being configured to interface with the decoder of the computer and to provide an FEC signal to the decoder over the hardware interface.

Abstract: The disclosed methods of low power communications facilitate high speed reception of data from an access point (AP) with low transmission latencies while remaining in power save mode as long as possible. The disclosed methods allow the client to remain in a power save state and involve creating a synchronous client frame exchange with the AP that is independent of a digital traffic indication map and the AP's beacon interval. Two methods to accomplish this goal are disclosed: one which involves sending PS Poll Frames; and one that includes fast CAM switching, both at a self tuning frequency.

Abstract: Transformer driven by data modulated signal provides isolated power. Outbound data is extracted from the data modulated signal received from the transformer. Inbound data received in isolated circuitry modulates the load presented to transformer. Inbound data perceived in non-isolated circuitry by sensing load experienced by the transformer.

Abstract: A method of rotating a digital image includes performing a first pass to process a selected image tile of a source image. The first pass includes copying a set of pixels of the selected image tile from a first memory to a processor memory, where the set of pixels comprises a portion of the selected image tile. The first pass further includes grouping the set of pixels into blocks of pixels and writing each of the blocks of pixels to a memory location. The method further includes repeating the first pass until each of the pixels of the selected image tile is processed, performing a second pass to process the blocks of pixels, and repeating the second pass until each of the blocks of pixels is processed. The second pass includes copying blocks of pixels, regrouping the blocks of pixels, and writing the regrouped pixels to a destination image location.

Abstract: A method for establishing a circuit connection over a network. Determining a channel quality profile of a medium connecting a source node and a destination node. Determining a throughput required to support a data rate requirement of an application that sources data. Determining a modulation type and modulation density at one or more frequency according to the channel quality profile. Selecting one or more of a set of frequencies, modulation types and modulation densities to support the throughput. Communicating the selection to nodes attached to the medium.

Abstract: A high availability backplane architecture. The backplane system includes redundant node boards operatively communicating with redundant switch fabric boards. Uplink ports of the node boards are logically grouped into trunk ports at one end of the communication link with the switch fabric boards. The node boards and the switch fabric boards routinely perform link integrity checks when operating in a normal mode such that each can independently initiate failover to working ports when a link failure is detected. Link failure is detected either by sending a link heartbeat message after the link has had no traffic for a predetermined interval, or after receiving a predetermined consecutive number of invalid packets. Once the link failure is resolved, operation resumes in normal mode.

Abstract: A hardware-based failover scheme enabling rapid end-to-end recovery is provided. Hardware logic periodically generates, transmits, receives, and processes heartbeat packets, sent from one end of the communications network to another, and then returned back. If a communications network node or communications link failure is being experienced along the transport path, then the hardware logic rapidly swaps the affected traffic conveyed to a pre-established backup transport path, typically within microseconds. Advantages are derived from the rapid failover effected end-to-end which enables continued delivery of provisioned communications services improving the resiliency and/or availability of a communications network.

Abstract: In today's environment class-D amplifiers are used to provide an integrated solution for applications such as powered audio devices due to their advantages in power consumption and size over more traditional analog amplifiers. Due to power output requirements, the output stages of power drivers such as class-D amplifiers require a supply voltage in excess of the technologically allowed voltage for the switches in the output stage. A level shifter is used to ensure voltages supplied to the output switches do not exceed the technological limits. An ideal level shifter should provide the optimal voltage swing to output switches under all process, supply voltage and temperature (PVT) variations. The ideal level shifter should also provide fast transitions when the control signal changes from high to low and low to high.

Abstract: Systems for suppressing image noise are provided. In this regard, one embodiment includes a system for suppressing image noise comprising a low noise amplifier (LNA) configured to amplify a received RF signal, an RF variable gain attenuator with an image rejection filter with programmable bandwidth configured to suppress image noise and image interference, and an RF mixer configured to perform frequency translation.