Weiliang Living Zhu

US Patent:

7529303, May 5, 2009

Filed:

Apr 10, 2007

Appl. No.:

11/733672

Inventors:

Alejandro Schwartzman - San Jose CA, US
Paul Lafferty - Hayward CA, US
Weiliang Zhu - San Jose CA, US
Timothy Finan - Milford NH, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04B 3/00
H04N 7/173

US Classification:

375257, 375222, 725111

Abstract:

Methods and apparatus are provided for determining transmission power levels. The power characteristics of a cable modem family are determined by testing cable modems in a cable modem family with various downstream frequencies and transmission power levels to determine internal gain levels. The power characteristics of the cable modem family can then be stored in an efficient manner in each cable modem by using interpolation. The individual cable modem can then be characterized by testing the cable modem with a limited set of downstream frequencies and transmission power levels to determine an internal gain level offset for that particular cable modem. With the power characteristics table, internal gain level offset, and interpolation, transmission power levels can be determined during network operation when downstream frequencies and internal gain levels are known.

US Patent:

7221712, May 22, 2007

Filed:

Dec 12, 2001

Appl. No.:

10/016032

Inventors:

Alejandro Schwartzman - San Jose CA, US
Paul Lafferty - Hayward CA, US
Weiliang Zhu - San Jose CA, US
Timothy Finan - Milford NH, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

H04B 3/00
H04N 7/173

US Classification:

375257, 375222, 725111

Abstract:

Methods and apparatus are provided for determining transmission power levels. The power characteristics of a cable modem family are determined by testing cable modems in a cable modem family with various downstream frequencies and transmission power levels to determine internal gain levels. The power characteristics of the cable modem family can then be stored in an efficient manner in each cable modem by using interpolation. The individual cable modem can then be characterized by testing the cable modem with a limited set of downstream frequencies and transmission power levels to determine an internal gain level offset for that particular cable modem. With the power characteristics table, internal gain level offset, and interpolation, transmission power levels can be determined during network operation when downstream frequencies and internal gain levels are known.