Broadcom Corporation

Stanford Telecommunications, Inc.

Augusta Technology, Inc.

Aki Shohara

Emilia Vailun Lei

Nelson Ray Sollenberger

Li Fung Chang

Yue Chen

Yongqian Wang

Joel Robert Williams

Allan Evans

April Hunter

Bryan Chase

Stephen Pope

Charles VanBlaricom

Charles Van Blaricom

Tung Chang

Yuo Chen

A method for operating a virtual whiteboard using a mobile phone device, comprises the steps of: generating the virtual whiteboard, wherein the mobile phone device is coupled to the virtual whiteboard to input data to the virtual whiteboard; connecting the mobile phone device to an external display device; displaying the virtual whiteboard on the external display device; and operating the virtual whiteboard using the mobile phone device; wherein markings on the virtual whiteboard correspond to spatial movements of the mobile phone device.

Systems and methods for operating a virtual whiteboard using a mobile phone device

Provided is a system for operating a communication device () for reception of scheduled intermittent information messages () with a dual mode timer () that extends battery life. A controller () schedules the timer () to power down all idle components of the device () between message receptions in a power saving sleep mode to conserve battery power. During active mode when the device is fully active in reception of messages, the timer () uses a reference oscillator () with a relatively high frequency to support digital processing by the receiver (). During sleep mode when only the timer is powered on, a much lower frequency sleep oscillator () is used to maintain the lowest possible level of power consumption within the timer itself. The timer () has provision for automatic temperature calibration to compensate for timing inaccuracies inherent to the low-power low-frequency crystal oscillator () used for the sleep mode. The resultant improvement in timer accuracy during sleep mode eliminates the need for an initial reacquisition period following wake up in active mode, thereby reducing battery drain in active mode as well.

Communication device with a self-calibration sleep timer

A system for implementing Incremental Redundancy (IR) operations in a wireless receiver includes a baseband processor, an equalizer, a system processor, and an IR processing module. The baseband processor receives an analog signal corresponding to a data block and samples the analog signal to produce samples. The equalizer receives the samples from the baseband processor, equalizes the samples, and produces soft decision bits corresponding to the data block. The equalizer may be implemented as a distinct processing component or may be performed by the baseband processor or system processor. The system processor receives at least the soft decision bits and initiates IR operations. The IR processing module receives the soft decision bits of the data block and performs IR operations on the data block in an attempt to correctly decode a corresponding data block.

Edge incremental redundancy support in a cellular wireless terminal

An improved method and apparatus for Viterbi Algorithm calculations for maximum likelihood sequence estimators in communication receivers is disclosed. The calculations for the maximum likelihood sequence estimator, in accordance with the invention, utilizes a variant of the Viterbi algorithm developed by Ungerboeck in which the associated branch metric calculations for the trellis require the computation of a set of branch metric parameters. An embodiment of the present invention provides for an improved recursive method and apparatus for calculation of the branch metric parameters that reduces the number of processor clock cycles required per state metric calculation. This enables real time computation of the branch metric parameters during execution of the Viterbi Algorithm.

Maximum likelihood sequence estimator which computes branch metrics in real time

The present invention provides for a system for operating a communication device () for reception of scheduled intermittent information messages () with a dual mode timer () that extends battery life. A controller () schedules the timer () to power down all idle components of the device () between message receptions in a power saving sleep mode to conserve battery power. During active mode when the device is fully active in reception of messages, the timer () uses a reference oscillator () with a relatively high frequency to support digital processing by the receiver (). During sleep mode when only the timer is powered on, a much lower frequency sleep oscillator () is used to maintain the lowest possible level of power consumption within the timer itself. The timer () has provision for automatic temperature calibration to compensate for timing inaccuracies inherent to the low-power low-frequency crystal oscillator () used for the sleep mode. The resultant improvement in timer accuracy during sleep mode eliminates the need for an initial reacquisition period following wake up in active mode, thereby reducing battery drain in active mode as well.

Communication device with a self-calibrating sleep timer

A method of compressing a puncture mask information is disclosed, the method comprising making a delayed puncture mask by deleting the last k bits of the puncture mask; and appending k zeros to the beginning of the puncture mask; making a differential puncture mask by XORing the delayed puncture mask with the puncture mask; and compressing the differential puncture mask.

Code puncturing method and apparatus

The present invention provides for a system and method for improvement of radio transmitter and receiver frequency accuracy for a local radio communication unit that communicates digital data with a remote communication unit. In the local unit the received radio signal is down-converted, and converted to complex baseband digital samples by an analog-to-digital converter. A downlink digital phase rotator applies a fine frequency shift to the samples in accordance with a receiver frequency offset command. The resultant baseband signal is used by the data demodulator and by a receiver frequency error estimator to obtain receiver frequency errors. A data modulator generates baseband complex samples which are shifted in carrier frequency by an integrated uplink digital phase rotator in accordance with a transmitter frequency offset command. The modulated samples are then converted by a digital-to-analog converter and upconverted in frequency for radio transmission to the remote unit. The local oscillator signals for both upconverter and downconverter are phase locked to a reference frequency generated by a VCXO. An automatic frequency control (AFC) function nulls the transmitter and receiver frequency error by the frequency adjustment commands to the uplink and downlink phase rotators or to the VCXO digital-to-analog converter (VCXO DAC) by feedback control principals based on measured receiver frequency error. During frequency track mode when communications between local and remote units are possible, the AFC only adjusts radio frequency via phase rotator commands and the VCXO command remains fixed, thereby avoiding communications performance degradation by VCXO frequency quantization error due to the VCXO DAC. The AFC adjusts VCXO frequency only during a preliminary acquisition mode prior to data communications, or to back out excessively large frequency offsets accumulated in the downlink and uplink phase rotators during track mode. When a VCXO adjustment is made in track mode, phase rotator adjustments are simultaneously applied to cancel the errors in transmitter and receiver radio frequencies caused by the step change due to VCXO frequency quantization thereby mitigating VCXO frequency quantization noise.

Radio frequency control for communication systems

A system and operation of the system for improvement of transmitter and receiver frequency accuracy for a local radio communication unit that communicates digital data with a remote communication unit. In the local unit, received signals are down-converted into complex baseband digital samples by A/D conversion. A downlink digital phase rotator applies a fine frequency shift in accordance with a receiver frequency offset command. The resultant baseband signal is used by the data demodulator and by a receiver frequency error estimator to obtain receiver frequency errors. A data modulator generates baseband complex samples which are shifted in carrier frequency by an integrated uplink digital phase rotator in accordance with a transmitter frequency offset command. The modulated samples are then converted by a D/A converter and upconverted in frequency for transmission to the remote unit. The local oscillator signals for both the upconverter and downconverter are phase locked to a reference frequency generated by a VCXO. An automatic frequency control (AFC) function nulls the transmitter and receiver frequency error by the frequency adjustment commands to the uplink and downlink phase rotators or to the VCXO D/A converter by feedback control principals based on measured frequency error. The AFC adjust VCXO frequency only during a preliminary acquisition mode prior to data communications, or to back out excessively large frequency offsets accumulated in the downlink and uplink phase rotators during track mode.

The present invention provides for a system for operating a communication device ( ) for reception of scheduled intermittent information messages ( ) with a dual mode timer ( ) that extends battery life. A controller ( ) schedules the timer ( ) to power down all idle components of the device ( ) between message receptions in a power saving sleep mode to conserve battery power. During active mode when the device is fully active in reception of messages, the timer ( ) uses a reference oscillator ( ) with a relatively high frequency to support digital processing by the receiver ( ). During sleep mode when only the timer is powered on, a much lower frequency sleep oscillator ( ) is used to maintain the lowest possible level of power consumption within the timer itself. The timer ( ) has provision for automatic temperature calibration to compensate for timing inaccuracies inherent to the low-power low-frequency crystal oscillator ( ) used for the sleep mode. The resultant improvement in timer accuracy during sleep mode eliminates the need for an initial reacquisition period following wake up in active mode, thereby reducing battery drain in active mode as well.

Radio frequency control for communications systems

The invention is a cellular radio system for terminals with narrowbeam antennas that provides demand assignment multiple access channel assignment under a guaranteed channel quality criterion. The invention features an efficient channel assignment algorithm that utilizes a database of measured the co-channel interference characteristics of subscriber terminals to eliminate significant co-channel interference in assigned channels. The use of measured terminal interference characteristics eliminates the occurrence of unexpected random occurrence of large co-channel interference in channel assignments thus permitting the use of more spectrally efficient cellular frequency reuse patterns.

DMA cellular radio system with a channel quality criterion

A network protocol for the delivery of wireless broadband integrated services digital network (ISDN) using asynchronous transfer mode (ATM).

Growing community of inventors

Sunnyvale, CA, United States of America

Aki Shohara