Method and apparatus for a cable modem upstream RF switching system

• US 6,477,197 B1
• Filed: 06/30/1998
• Issued: 11/05/2002
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: Arris International, Inc. (CommScope Holding Company, Inc.)
• Inventors: Unger, David
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): JIANG, LENNY R
• Application Number:
  US09/109,258
• Time in Patent Office: 1,589 Days
• Field of Search: 375/147, 375/316, 375/324, 375/328, 375/338, 375/340, 375/346, 375/347, 375/349, 375/220, 375/222, 375/260, 375/267, 333/1, 333/100, 333/101, 333/105, 333/106, 370/357, 370/360, 370/351-430, 455/179.1, 455/180.1, 455/132, 455/133, 455/134, 455/135-140, 455/31.1, 455/32.1, 455/161.1, 455/161.2, 329/327, 329/315
• US Class Current: 375/222
• CPC Class Codes: H04B 1/44 Transmit/receive switching
• CPC Class Codes: H04L 12/2801 Broadband local area networks

Abstract

A method and apparatus providing for a multifrequency receiver with upstream switching of received frequencies. The invention is described in connection with a cable plant having a plurality of modems transmitting at a first frequency. It may be desirable to locate a second frequency having more desirable transmission characteristics and to cause the modems to transmit at the second frequency. It is disclosed to utilize an additional receiver coupled through a switch which may be used to both locate a desirable frequency and to facilitate automatic switching of the cable modems from the first frequency to the second frequency.

Claims

1. A method of switching a plurality of cable modems from transmission on a first frequency to transmission on a second frequency comprising the steps of:

a) receiving transmissions from a first cable modem and a second cable modem on the first frequency through a first receiver tuned to the first frequency;

b) tuning a second receiver to the second frequency;

c) instructing the first cable modem to transmit on the second frequency; and

d) instructing the second cable modem to transmit on the second frequency.

2. The method as recited by claim 1 further comprising the step of programming the first receiver to receive on the second frequency.

3. A cable modem termination system for switching a plurality of cable modems from transmission on a first frequency to transmission on a second frequency, comprising:

a) means for receiving transmissions from a first cable modem and a second cable modem on the first frequency through a first receiver tuned to the first frequency;

b) means for tuning a second receiver to the second frequency;

c) means for instructing the first cable modem to transmit on the second frequency; and

d) means for instructing the second cable modem to transmit on the second frequency.

4. The system as recited by claim 3 further comprising means for programming the first receiver to receive on the second frequency.

5. The system as recited by claim 3, wherein the means for receiving transmissions being a receiver to act as a spectrum analyzer by scanning any part of an input signal spectrum of a transmission.

6. The system as recited by claim 5, wherein the means for receiving transmissions further includes a switch to set the receiver to act as the spectrum analyzer.

7. The system as recited by claim 6, wherein the receiver of the means for receiving transmissions can alternatively be configured to act as a backup receiver for one of the first receiver and the second receiver.