Abstract: Stations in standby mode periodically wake up to check for buffered data at the access points. Traditionally, the information is available by checking the periodic beacon frame for a traffic indication map (TIM). Unfortunately, the length of beacons has steadily increased with the progression of the various wireless standards requiring stations to wake up for longer periods to merely check for buffered data. Several approaches are disclosed which address this shortcoming, including the broadcast of TIM frames, the partial reception of beacon frames and the use of an embedded TIM frame within a beacon frame.

Abstract: A system for halftone processing is provided. The system includes a programmable halftone segmentation system having one or more programmable parameters to accommodate different input image parameters, such as different printer or scanner parameters, and configured to generate output control data as a function of image input data. A programmable output processor receives the output control data and the image input data and generates image output data that compensates for halftone regions in the image input data.

Abstract: Disclosed herein are systems and methods of combined Bluetooth and WLAN signaling. Such systems and methods may use a Bluetooth connection to signal WLAN capabilities and to exchange WLAN security keys. Once the file transfer has started, the actual data may be transmitted over the WLAN connection rather than over the Bluetooth connection. The WLAN connection may have a much higher throughput than the Bluetooth connection, and WLAN capability has increasingly become present inside Bluetooth enabled devices. The Bluetooth connection may be used as a control channel, while the WLAN connection may be used for data transfer.

Abstract: A level shifter comprising a first driver transistor receiving an input signal. A gate-controlled transistor coupled to the first driver transistor. A second driver transistor coupled to the gate controlled transistor. An output coupled to the second driver transistor, wherein the gate-controlled transistor is for receiving a predetermined gate voltage when the output voltage exceeds a predetermined value.

Abstract: Systems and methods for coexistence of WLAN and Bluetooth networks are described. At least one embodiment includes a method for operating a wireless device in both a 802.11 network and a Bluetooth network. In accordance with some embodiments, the method comprises monitoring transmission of Synchronous Connection Oriented (SCO) slots over the Bluetooth network, informing an access point (AP) in the 802.11 network not to transmit to the device before the end of an SCO slot, transmitting a power save trigger to the AP to retrieve buffered data from the AP, and transmitting data to the AP.

Abstract: There is provided a method for use in a computer for redirecting an audio stream from a first audio endpoint to a second audio endpoint in the computer having a controller and a computer operating system for execution by the controller. The method includes directing the audio stream from a client application running on the computer operating system through a first audio resource stack of the computer to the first audio endpoint. The method further includes creating an audio endpoint bridge using the computer operating system, where the audio endpoint bridge provides a path for the audio stream to be directed from the first audio resource stack to pass through a second audio resource stack to the second audio endpoint. The method may also enhance the audio stream to reduce noise and redirect the audio stream to the second audio endpoint using the audio endpoint bridge.

Abstract: A device comprising a detector configured to receive an indication from a terminal of a connector and to determine whether the indication matches an expected result. One or more first switches are configured to connect one or more speaker transducers to the connector if the indication is false. One or more second switches are configured to connect the one or more speaker transducers to a digital output converter if the indication is true. The device can also include one or more third switches configured to connect one or more microphone elements to the connector if the indication is false, and one or more fourth switches configured to connect one or more microphones to a digital input converter if the indication is true. The input and output converters can be stand alone or part of a digital signal processor.

Abstract: In many audio playback systems, frequencies below a given cut off frequency are suppressed either due to speaker constraints or safety constraints. For example, some speakers are only capable of generating signals above a certain frequency. Prolonged low frequency sound can cause damage to speakers or other components. An audio driver can be equipped with a phantom bass module which by doubling, tripling and/or quadrupling frequencies below a cutoff frequency can simulate the bass experience. The doubling, tripling and quadrupling methods disclosed provide a low complexity formulation of a frequency doubling, tripling and quadrupling. In addition, the frequency doubling, tripling and quadrupling formulations are easily adapted to multi-rate processing, where computational savings can be very high.

Abstract: Traditionally, echo cancellation has employed linear adaptive filters to cancel echoes in a two way communication system. The rate of adaptation is often dynamic and varies over time. Disclosed are novel rates of adaptation that perform well in the presence of background noise, during double talk and with echo path changes. Additionally, the echo or residual echo can further be suppressed with non-linear processing performed using joint frequency-time domain processing.

Abstract: A grounding switch is described which operates properly even in the presence of negative voltages on a signal line. The grounding switch uses isolated field effect transistors that have their substrates tied to different voltages. The isolated field effect transistor has a gate voltage and substrate voltage which can be pulled down to a negative voltage when the signal line has a negative voltage allowing the switch to remain open even with a negative voltage.

Abstract: A system for booting a processor from NAND flash, comprising a NAND agnostic boot controller and a NAND flash device, wherein the NAND flash device further comprises a boot wrapper storing boot code in a predetermined format.

Abstract: A database system comprising a plurality of access keys stored in a first data memory device sector, each access key associated with a node value stored in a second data memory device sector. An access key processor configured to receive an input value and return the associated node value for the input value if the input value matches an access key stored in the first data memory device sector. The access key processor is configured to generate a revised input value if the input value does not match an access key stored in the first data memory device; a default node value stored in the second data memory device sector and associated with a portion of the input value, wherein the access key processor is configured to return the default node value as part of the revised input value.

Abstract: Biphase mark codes (BMC) are used in digital communications. Most BMC formats use preambles for rate determination and synchronization. A decoder compares the intervals of continuous high or continuous low voltages in a BMC stream to predetermined minimum and maximum values of half cell, full cell and one-and-a-half cell intervals for all supported sampling rates. If a pattern matching a preamble is found, the sampling rate is locked in and the decoder is synchronized to the BMC stream. Once locked, the decoder uses the predetermined minimum and maximum values at the locked rate to generate half cell, full cell and one-and-a-half cell indicators for a decoding state machine which decodes data in the BMC stream or decodes expected preambles.

Abstract: Systems and methods for broadcast and multicast retransmissions within a protected wireless communications system are described. Retransmitted broadcast or multicast frames are designated by modification of fields or subfields in the MAC header of the frame which are constituent parts of the additional authentication data used to generate encryption keys. Such modifications cause legacy receivers to disregard the retransmitted frames or render legacy receivers to be unable to decrypt the retransmitted frame, avoiding the generation of duplicate frames. Non-legacy receivers recognizing the modification conventions can restore the MAC header to the original state and can reconstruct the original encryption keys and decrypt the retransmitted frames. A non-legacy transmitter can retransmit a frame without the need to re-encrypt the frame.

Abstract: High linearity is essential in audio circuitry. As sampling rates for audio applications are needed, high speed and high linearity are needed in analog and mixed signal portions of audio circuitry such as in current mirrors. A current mirror employs two current paths in an output. The first current path is driven by a fast acting transistor through a resistor. The second current path is driven by a differential amplifier coupled to another transistor through another resistor. The second current path is used to maintain linearity by causing the voltage across both transistors to be the same.

Abstract: A circuit comprising a first input transistor having a drain, a source and a gate. A first diode connected transistor having a drain, a source and a gate, wherein the gate of the first diode connected transistor is coupled to the drain of the first diode connected transistor, and the drain of the first input transistor is coupled to the drain of the first diode connected transistor. A first load transistor having a drain, a source and a gate, wherein the drain of the first load transistor is coupled to the drain of the first diode connected transistor and the source of the first load transistor is coupled to the source of the first diode connected transistor.

Abstract: A reconfigurable amplifier comprising a first operational amplifier having two inputs and an output. A second operational amplifier having two inputs and an output. A plurality of switches coupled to the two inputs and the output of the first operational amplifier and the two inputs and the output of the second operational amplifier, wherein a first configuration of the plurality of switches causes the first operational amplifier and the second operational amplifier to operate as an inverting differential input amplifier, and wherein a second configuration of the plurality of switches causes the first operational amplifier and the second operational amplifier to operate as a non-inverting differential input instrumentation amplifier.

Abstract: A dual-voltage receiver, comprising a voltage detector. A high voltage Schmitt trigger coupled to the voltage detector. A low voltage Schmitt trigger coupled to the voltage detector. A combined level shifter coupled to the high voltage Schmitt trigger and the low voltage Schmitt trigger, wherein the high voltage Schmitt trigger is on and the low voltage Schmitt trigger is off when the voltage detector outputs a high voltage detect signal.

Abstract: Modern electronic devices are getting more portable and smaller leading to smaller distances between speakers. In particular, computers are now so compact that the notebook computer is one of the most popular computer types. However, with the proliferation of media available in digital form, both music recordings and video features, the demand for high quality reproductions on computers has increased. Systems and methods for producing wider speaker effects and immersion effects disclosed can enhance a listener's experience even in a notebook computer.

Abstract: Provided is a fully differential adaptive bandwidth phase locked loop with differential supply regulation. One fully differential phase locked loop includes a differential active loop filter and regulator coupled to an output of a differential charge pump, a differential voltage-controlled oscillator coupled to differential control voltages developed by the differential active loop filter and regulator, and a bias circuit coupled to the differential control voltages and providing a bias current to the differential charge pump.