Wi-Lan Inc.

Freescale Semiconductor,inc.

Ensemble Communications, Inc.

Frederick Wales Price

Sheldon I Gilbert

Eli Arviv

David Gazelle

Kenneth L Stanwood

Israel Jay Klein

Stephen C Pollmann

Rami Hadar

Steve Pollmann

Timothy Leo Gallagher

Yair Bourlas

Blaine Clifford Readler

John Wiss

Pranesh Sinha

Sharon Akler

Jacques Behar

Theodore Jon Myers

Robert W Boesel

Lewis Neal Cohen

Tien Q Nguyen

Timothy L Gallagher

Kenneth Canullas Sinsuan

Ell Arviv

A method of simplifying the encoding of a predetermined number of bits of data into frames including adding error coding bits so that a ratio of the frame length times the baud rate of the frame times he bit packing ratio of the data divided the total bits of data is always an integer. The method may also convolutionally encode the bits of data so that the same equation is also always an integer.

Frame structure for an adaptive modulation wireless communication system

A method of simplifying the encoding of a predetermined number of bits of data into frames including adding error coding bits so that a ratio of the frame length times the baud rate of the frame times the bit packing ratio of the data divided the total bits of data is always an integer. The method may also convolutionally encode the bits of data so that the same equation is also always an integer.

Apparatus, system and method for synchronizing one or more clocks across a communication link. A slave clock may be synchronized to a master clock by means of a synchronization signal sent from the master to the slave clock side of the link. The synchronization signal may be an expected signal pattern sent at intervals expected by the slave side. The slave clock may correlate received signals with a representation of the expected synchronization signal to produce a correlation sample sequence at a first sample rate which is related as n times the slave clock rate. The synchronization signal receipt time indicated by the correlation sample sequence may be refined by interpolating the correlation sample sequence around a best correlation sample to locate a best interpolation at an interpolation resolution smaller than the sample resolution. The best interpolation may in turn be further refined by estimating between interpolator outputs adjacent to the best interpolation output. The synchronization signal receipt time thus determined is compared to the expected time based upon the slave clock, which is adjusted until the times match. After initialization, all slave clock errors are preferably accumulated to prevent long-term slip between the slave and master clocks. Formerly independent master and slave clocks synchronized across the communication link constitute a noncommon clock which may be compared on each side of the link to secondary independent clocks, and the secondary independent clocks may then be separately synchronized by adjusting one to have the same difference from its local noncommon clock as the secondary clock on the other side of the link has from its local noncommon clock.

Synchronizing clocks across a communication link

A slave clock may be synchronized to a master clock by means of a synchronization signal sent from the master to the slave clock side of the link. The synchronization signal may be an expected signal pattern sent at intervals expected by the slave side. The slave clock may correlate received signals with a representation of the expected synchronization signal to produce a correlation sample sequence at a first sample rate which is related as n times the slave clock rate. A best interpolation may in turn be further refined by estimating between interpolator outputs adjacent to the best interpolation output. The synchronization signal receipt time thus determined is compared to the expected time based upon the slave clock, which is adjusted until the times match. The best interpolation may in turn be further refined by estimating between interpolator outputs adjacent to the best interpolation output.

One or more clocks are synchronized across a communication link using a synchronization signal sent from a master to a slave clock. The synchronization signal may be an expected signal pattern sent at intervals expected by the slave. The slave clock may correlate received signals with a representation of the expected synchronization signal to produce a correlation sample sequence at a first sample rate. The synchronization signal receipt time is compared to the expected time and the slave clock is adjusted until the times match. Master and slave clocks synchronized across the communication link constitute a noncommon clock which may be compared on each side of the link to secondary independent clocks. The secondary independent clocks may be separately synchronized by adjusting one to have the same difference from its local noncommon clock as the secondary clock on the other side of the link has from its local noncommon clock.

The present invention is a method of simplifying the encoding of a predetermined number of bits of data into frames. The method adds error coding bits so that a ratio of the frame length times the baud rate of the frame times the bit packing ratio of the data divided the total bits of data is always an integer. The method may also convolutionally encode the bits of data so that the same equation is also always an integer.

A system and method for obtaining processor diagnostic data. The method can include receiving a instruction, enabling write access of an output stream to a diagnostic memory, writing to the diagnostic memory at a first frequency, and reading from the diagnostic memory at a second frequency where the first frequency is greater than the second frequency.

System and method for selectively obtaining processor diagnostic data

Base stations having potentially interfering terminal stations that are geographically located on the same or similar diagonal or Line of Sight (relative to the base station) operate on a first set of time frames (e.g., 'even' time frames). Similarly, base stations having potentially interfering terminal stations that are not geographically located on the same or similar diagonals operate on a second set of time frames (e.g., 'odd' time frames). By alternating in their use of the even and odd frames, the potential for co-channel interference between terminal stations is minimized. Systems and methods are disclosed which reduce co-channel and adjacent channel interference between terminal stations of different cells as well as adjacent channel interference between terminal stations of adjacent cells. The methods and systems so described can be used during the deployment or expansion of a communication system in a region.

Method and system for reducing channel interference in a frame-synchronized wireless communication system

A method of assigning downlink time slots to receive units where the units may generate data using different modulation schemes. The method preferably assigns the downlink time slots as a function of the complexity of modulation schemes employed by the units. Further, the method preferably assigns the time slots from the least complex modulation scheme to the most complex scheme. The method may further assign uplink time slots to transmit units where the transmit units may generate data using different modulation schemes. The method preferably assigns the uplink time slots as a function of the complexity of modulation schemes employed by the uplink units. Further, the method preferably assigns the uplink time slots from the least complex modulation scheme to the most complex scheme. In other embodiments, the downlink time slots are assigned as a function of the bit per symbol rate employed by the receive units, preferably from the lowest bit per symbol rate to the highest bit per symbol rate. Further, the uplink time slots are assigned as a function of the bit per symbol rate employed by the transmit units, preferably from the lowest bit per symbol rate to the highest bit per symbol rate. The present invention is also a method of simplifying the encoding of a predetermined number of bits of data into frames. The method adds error coding bits so that a ratio of the frame length times the baud rate of the frame times the bit packing ratio of the data divided the total bits of data is always an integer. The method may also convolutionally encode the bits of data so that the same equation is also always an integer. The present invention is also a method of updating the weights of a FIR filter where the filter processes symbols having variable modulation rates. When the modulation rate of the incoming symbols changes, the weights corresponding to the first symbol having the new modulation rate are changed based as the symbol propagates through the filter.

A system and method for enhancing the performance of an equalizer in a modem. Multiple techniques are disclosed which improve the modem performance. A first technique uses stored parameters for each burst from each remote site to demodulate a received data stream. A second technique compensates for the gain droop caused by storing parameters across each burst. A third technique minimizes errors caused by adapting the equalizer coefficients for each data burst by analyzing the SN ratio and error rate of the received burst. A fourth technique improves the convergence of the equalizer by using a two-part preamble, whereby both parts are transmitted using different modulation techniques. A fifth technique is provided which performs a soft reset of the modem without performing a complete reset of the modem. A sixth technique determines a modem adaptation factor based on the expected modulation type of an incoming burst transmission. A seventh technique calculates a phase correction value for the stored tap values and applies the value to the incoming signal.

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Carlsbad, CA, United States of America

Frederick Wales Price