Michael A Pollack

US Patent:

6408165, Jun 18, 2002

Filed:

Jul 6, 1999

Appl. No.:

09/348719

Inventors:

Ali Raissinia - Monte Sereno CA
Derek Gerlach - Mountain View CA
Gregory G. Raleigh - El Granada CA
Michael Pollack - Cupertino CA

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04B 100

US Classification:

455 69, 455 68, 455522

Abstract:

Improved adjustment of transmission power in a communication system is provided. In one embodiment, in a point to multipoint communication system, transmission power of a subscriber unit is controlled based on power measurements made at a central access point. Power measurement information based on transmissions occurring at irregular intervals may be combined in a beneficial manner to control transmission output power. In one embodiment, a power regulation process determines a series of difference values indicating the differences between desired received power level at the central access point and measured received power level. A smoothing process is applied to the difference values. One or more parameters of the smoothing process vary with elapsed time since a last available power measurement.

US Patent:

6430193, Aug 6, 2002

Filed:

Jul 6, 1999

Appl. No.:

09/348647

Inventors:

Ali Raissinia - Monte Sereno CA
Michael Pollack - Cupertino CA
Gregory G. Raleigh - El Granada CA

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04L 12413

US Classification:

370448, 370469, 370476, 714752

Abstract:

Systems and methods are provided for transferring physical layer control information from a central access point to individual subscriber units while maintaining transparency to higher layers. Adaptation of wireline MAC protocols to wireless applications is greatly facilitated. Subscriber unit power level may be controlled from the central access point.

US Patent:

6452981, Sep 17, 2002

Filed:

Nov 5, 1999

Appl. No.:

09/435293

Inventors:

Gregory G. Raleigh - El Granada CA
Michael A. Pollack - Cupertino CA

Assignee:

Cisco Systems, Inc - San Jose CA

International Classification:

H04L 2712

US Classification:

375299, 375296, 375347, 375349

Abstract:

A space-time signal processing system with advantageously reduced complexity. The system may take advantage of multiple transmitter antenna elements and/or multiple receiver antenna elements, or multiple polarizations of a single transmitter antenna element and/or single receiver antenna element. The system is not restricted to wireless contexts and may exploit any channel having multiple inputs or multiple outputs and certain other characteristics. Multi-path effects in a transmission medium cause a multiplicative increase in capacity.

US Patent:

6463096, Oct 8, 2002

Filed:

Jun 12, 1998

Appl. No.:

09/097305

Inventors:

Gregory G. Raleigh - El Granada CA
Vincent K. Jones - Redwood Shores CA
Michael A. Pollack - Cupertino CA

Assignee:

Cisco Systems, Inc - San Jose CA

International Classification:

H04B 1700

US Classification:

375225, 375221, 370473

Abstract:

Method and apparatus for combining high data rate traffic and low data rate traffic on a common transmission medium while maximizing efficient use of available spectrum. Since spectrum is an economically valuable resource and transport of data generates revenue, the present invention directly leads to more profitable network operation. The disclosed systems are applicable to both wired and wireless transmission media. In one embodiment, a bandwidth reservation scheme provides that data rate may be varied so that when a particular data communication device is allocated a frame, it is also assigned a data rate for use in that frame. Because bandwidth usage varies with data rate, the division of available spectrum into channels for use by individual data communication devices may also vary among frames.

US Patent:

6621872, Sep 16, 2003

Filed:

Mar 31, 1999

Appl. No.:

09/282516

Inventors:

Vincent K. Jones - Redwood Shores CA
Michael Pollack - Cupertino CA
Gregory G. Raleigh - El Granada CA

Assignee:

Cisco Technology Inc. - San Jose CA

International Classification:

H04L 2302

US Classification:

375265, 375341

Abstract:

Systems and methods for communicating medium access control (MAC) data without errors. Different encoding processes may be used to encode MAC data and data unrelated to MAC. The encoding processes used for MAC data employ more redundancy and are therefore capable of transmitting data without errors in more severe conditions than the encoding processes used for non-MAC data. Both MAC data and non-MAC data may be represented as a series of so-called symbols where each symbol is a complex value used to modulate a sinusoidal carrier signal. MAC data transmissions may employ a set of symbols having more widely spaced complex values than the symbol set used for non-MAC data transmissions. While the receiver is receiving MAC data, it may more easily distinguish which symbols have been sent, even when the symbols have been heavily corrupted with noise and interference. Thus network operation may be properly coordinated even in the presence of severe degradation of data transmission quality.

US Patent:

6657950, Dec 2, 2003

Filed:

Feb 19, 1999

Appl. No.:

09/253152

Inventors:

James M. Gardner - San Jose CA
Michael Pollack - Cupertino CA

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04J 1100

US Classification:

370208, 370210, 375260

Abstract:

Systems and methods for converting a baseband OFDM signal to an IF signal while minimizing lengthening of the impulse response duration experienced by the OFDM signal. A conversion technique according to the present invention provides sufficient filtering to limit the effects of spurious frequency domain components caused by transitions between successive OFDM bursts. In one embodiment, the filtering is provided by a combination of a finite impulse response (FIR) filter having non-linear phase characteristics and a cyclic convolution filter. Conversion from the frequency domain into the time domain, upsampling, and cyclic filtering may be combined into one operation.

US Patent:

6788950, Sep 7, 2004

Filed:

Jul 6, 1999

Appl. No.:

09/348645

Inventors:

Ali Raissinia - Monte Sereno CA
Gregory G. Raleigh - El Granada CA
Michael Pollack - Cupertino CA

Assignee:

Cisco Technology Inc. - San Jose CA

International Classification:

H04B 700

US Classification:

455522, 455 69, 455 70, 370311, 370203

Abstract:

Systems and methods for controlling subscriber unit power level using power measurements made on access request transmissions. Since a subscriber unit access request typically precedes a subscriber unit data transmission by a relatively short period of time, the data transmission power level will then be based on a recent power measurement. The access request may also trigger a sequence of power control steps including the transmission of special upstream power measurement transmissions which can be used as the basis for even more accurate power control. These power control features are particularly useful in fading environments such as found in a wireless system.

US Patent:

6795426, Sep 21, 2004

Filed:

Jun 23, 2000

Appl. No.:

09/603237

Inventors:

Gregory G. Raleigh - Woodside CA
Ali Raissinia - Monte Sereno CA
Michael Pollack - Cupertino CA

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04J 300

US Classification:

370345, 370252, 370210

Abstract:

Systems and methods for efficiently transmitting power level information in a point to multipoint wireless system. Multiple subscriber units may transmit indications of their power level within a shared burst where one or more subchannels are allocated to each subscriber unit. The burst holding the power level information may be understood by the MAC layer to be a data burst. In this way, a wireline MAC protocol may be applied to wireless applications.