Method and apparatus for transceiver noise reduction in a frame-based communications network

• US 7,254,116 B2
• Filed: 04/04/2001
• Issued: 08/07/2007
• Est. Priority Date: 04/07/2000
• Status: Expired due to Fees

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Trachewsky, Jason Alexander, Yamano, Larry C., Robinson, Timothy B., Snow, Dane R.
• Primary Examiner(s): Pham; Chi
• Assistant Examiner(s): Jagannathan; Melanie
• Application Number:
  US09/825,638
• Publication Number:
  US 20010046289A1
• Time in Patent Office: 2,316 Days
• Field of Search: 370/282, 370/286, 370287-290, 370/284, 370/201, 379/406.8, 379/416, 379/404
• US Class Current: 370/278
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0005 applied to payload information
• CPC Class Codes: H04L 1/0006 by adapting the transmission format
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 1/1848 Time-out mechanisms
• CPC Class Codes: H04L 1/1877 for semi-reliable protocols, e.g. for less sensitive applications like streaming video buffer level management for video bitstream control arrangements H04N21/44004
• CPC Class Codes: H04L 1/1883 using multiple timers
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 12/40032 Details regarding a bus interface enhancer
• CPC Class Codes: H04L 12/4013 Management of data rate on the bus systems modifying transmission characteristics according to link quality H04L1/0001
• CPC Class Codes: H04L 12/40136 Nodes adapting their rate to the physical link properties LAN switches H04L49/351
• CPC Class Codes: H04L 12/40156 by using dedicated slots associated with a priority level
• CPC Class Codes: H04L 12/40163 by assigning priority to messages according to a message field
• CPC Class Codes: H04L 12/403 : with centralised control, e.g. polling
• CPC Class Codes: H04L 12/4035 : in which slots of a TDMA packet structure are assigned based on a contention resolution carried out at a master unit TDM/TDMA multiplex systems per se H04J3/1694; hybrid switching systems H04L12/64
• CPC Class Codes: H04L 12/407 : with decentralised control
• CPC Class Codes: H04L 12/413 : with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/417 : with deterministic access, e.g. token passing
• CPC Class Codes: H04L 2001/0093 : Point-to-multipoint
• CPC Class Codes: H04L 2001/125 : Arrangements for preventing errors in the return channel
• CPC Class Codes: H04M 11/00 : Telephonic communication systems specially adapted for combination with other electrical systems
• CPC Class Codes: H04M 11/06 : Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors
• CPC Class Codes: Y02D 30/50 : in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method of and apparatus for noise reduction for a transceiver transmitting frames over a transmission medium in a frame-based communications network. A transceiver transmit path and a transceiver receive path is provided. A blocking switch is located in the transceiver transmit path, the blocking switch allowing transmit signal propagation when enabled, while preventing both transmit signal propagation and circuit device noise coupling from the transceiver transmit path to the transceiver receive path when the blocking switch is disabled. The blocking switch is disabled when the transceiver transmit path is not transmitting frames over the frame-based communications network.

Claims

1. A method of noise reduction for a received signal in a transceiver communicating frames over a transmission medium in a frame-based communications network comprising:

providing a transceiver transmit path and a transceiver receive path in the transceiver;

locating a blocking switch in the transceiver transmit path, the blocking switch allowing transmit signal propagation when enabled, while preventing both transmit signal propagation and circuit device noise coupling from the transceiver transmit path to the transceiver receive path when the blocking switch is disabled so as to reduce noise in the received signal; and

disabling the blocking switch when the transceiver transmit path is not transmitting frames over the frame-based communications network.

2. The method of claim 1, wherein the circuit device noise coupling from the transceiver transmit path to the transceiver receive path is through a transformer providing conversion from four wire transmit receive lines to a two wire line.

3. The method of claim 1, wherein the blocking switch is located proximate to the transmission medium.

4. The method of claim 3, wherein the transmission medium is a twisted pair wire.

5. The method of claim 4, wherein the twisted pair wire is a telephone line.

6. A switch apparatus for providing noise reduction for a received signal in a transceiver communicating frames over a transmission medium in a frame-based communication network, the transceiver having a transceiver transmit path and a transceiver receive path, comprising:

a blocking switch locatable in the transceiver transmit path, the blocking switch having an input port and an output port allowing transmit signal propagation through the blocking switch and along the transceiver transmit path when enabled, the blocking switch further including enable/disable control to disable the blocking switch when the transceiver transmit path is not transmitting frames over the frame-based communications network preventing both transmit signal propagation and circuit device noise coupling from the transceiver transmit path to the transceiver receive path when the blocking switch is disabled so as to reduce noise in the received signal.

7. The switch apparatus of claim 6, wherein the circuit device noise coupling from the transceiver transmit path to the transceiver receive path is from an output port through a transformer providing conversion from four wire transmit receive lines to a two wire line.

8. The switch apparatus of claim 6, wherein the output port of the blocking switch is locatable proximate to the transmission medium.

9. The switch apparatus of claim 8, wherein the transmission medium is twisted pair wire.

10. The switch apparatus of claim 9, wherein the twisted pair wire is a telephone line.