Full duplex wideband communications system for a local coaxial network

• US 8,094,640 B2
• Filed: 08/23/2004
• Issued: 01/10/2012
• Est. Priority Date: 01/15/2003
• Status: Expired due to Fees

• Current Assignee: Magnolia Licensing LLC (IP Edge LLC)
• Original Assignee: Scientific-Atlanta LLC (Cisco Systems, Inc.)
• Inventors: Robertson, Neil C., Fernandez, Jose M.
• Primary Examiner(s): MILLER, BRANDON J
• Application Number:
  US10/924,077
• Publication Number:
  US 20050030910A1
• Time in Patent Office: 2,696 Days
• Field of Search: 370343-344, 370/295, 370/330, 370276-278, 370281-282, 370/277, 370/329, 725/118, 725/111, 725/126, 455/450
• US Class Current: 370/343
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 5/143 for modulated signals H04L5/1469 takes precedence
• CPC Class Codes: H04N 21/42676 for modulating an analogue carrier signal to encode digital information or demodulating it to decode digital information, e.g. ADSL or cable modem
• CPC Class Codes: H04N 21/43615 Interfacing a Home Network, e.g. for connecting the client to a plurality of peripherals home Audio Video Interoperability [HAVI] data switching networks H04L12/2805
• CPC Class Codes: H04N 21/43632 involving a wired protocol, e.g. IEEE 1394 high-speed IEEE 1394 serial bus H04L12/40052
• CPC Class Codes: H04N 21/438 Interfacing the downstream path of the transmission network originating from a server, e.g. retrieving encoded video stream packets from an IP network
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/104 Switchers or splitters
• CPC Class Codes: H04N 7/106 for domestic distribution

Abstract

Systems and methods are disclosed for a full duplex wideband communications system for a local (e.g. in-home) coaxial network. The system employs a Frequency-division duplex (FDD) scheme that allows identical wideband modems to communicate with each other. To achieve this, the wideband modems contain a duplexer and a switch that allows reversing the connection of the wideband transmitter and receiver to the duplexer. Each wideband modem includes a control modem that is used to control access to the wideband channels. A wideband transmitter, which may be included in a modem associated with a server set-top terminal (STT), transmits a video presentation to a wideband receiver, which may be included in a modem associated with a client STT.

Claims

1. A full duplex wideband modem, comprising:

a wideband transmitter for transmitting high data rate communications;

a wideband receiver for receiving high data rate communications;

a band select switch coupled to the transmitter and receiver for selecting one of a high band or a low band in accordance with a first unused frequency associated with transmitted high data rate communications and selecting a second unused frequency in the unselected high band or low band associated with received high data rate communications,

wherein the band select switch passes both the transmitted high data rate communications and the received high data rate communications,

a duplexer for isolating the wideband receiver from the wideband transmitter, wherein the band select switch reverses the connection of the wideband transmitter and the wideband receiver to a high-pass and a low-pass port of the duplexer,

wherein the duplexer attenuates the transmitted high data rate communications, and

wherein the full duplex wideband modem communicates with a second full duplex wideband modem when the band select switch of each full duplex wideband modem is set in opposite positions.

2. The full duplex wideband modem of claim 1, further comprising:

a control transmitter for sending control information to at least one coupled full duplex wideband modem, wherein the control information includes the first unused frequency and the second unused frequency of at least one connected full duplex wideband modem, wherein the control information instructs one of the at least one coupled full duplex wideband modem to receive the high data rate communications in the first unused frequency and transmit the high data rate communications in the second unused frequency and informs the remaining coupled full duplex wideband modems that the first and second unused frequencies are no longer unused; and

a control receiver for receiving control information from the at least one coupled full duplex wideband modem.

3. The full duplex wideband modem of claim 2, wherein a high frequency band includes a plurality of frequencies in which to transmit and receive the high data rate communications, and wherein a low frequency band includes a plurality of frequencies in which to transmit and receive the high data rate communications, wherein the used frequencies are currently in use by other coupled full duplex wideband modems.

4. The full duplex wideband modem of claim 1, wherein the high data rate communications is a video presentation.

5. A coaxial network for communicating high data rate signals, the coaxial network comprising a plurality of wideband modems for transmitting and receiving high data rate communications between two or more of the plurality of modems in the coaxial network, a wideband modem comprising:

a transmitter for transmitting the high data rate communications;

a receiver for receiving the high data rate communications; and

a band select switch coupled to the transmitter and receiver for selecting one of a high band or a low band in accordance with a first unused frequency associated with transmitted high data rate communications and a second unused frequency associated with received high data rate communications,

wherein the band select switch passes both the transmitted high data rate communications and the received high data rate communications,

a duplexer for isolating the wideband receiver from the wideband transmitter, wherein the band select switch reverses the connection of the wideband transmitter and the wideband receiver to a high-pass and a low-pass port of the duplexer,

wherein the duplexer attenuates the transmitted high data rate communications, and

wherein the band select switch of one of the plurality of wideband modems and a band select switch of a second of the plurality of wideband modems communicate with each other when the band select switches are set in opposite positions.

6. The coaxial network of claim 5, wherein the high data rate communications include a video presentation.

7. The coaxial network of claim 5, wherein the duplexer is coupled to the band select switch for receiving and providing the transmitted high data rate communications to the coaxial network, and for receiving and providing the received high data rate communications to the band select switch, wherein the high data rate communications are isolated from other signals by a high pass filter.

8. The coaxial network of claim 7, the wideband modem further comprising a control modem for providing information regarding the first unused frequency associated with the transmitted high data rate communications and the second unused frequency associated with the received high data rate communications.

9. The coaxial network of claim 8, wherein the control modem comprises:

a control transmitter for providing the information to the plurality of wideband modems; and

a control receiver for receiving information from the plurality of wideband modems.

10. The coaxial network of claim 9, wherein a high frequency band includes a plurality of frequencies in which to transmit and receive the high data rate communications, and wherein a low frequency band includes a plurality of frequencies in which to transmit and receive the high data rate communications, wherein the selected first and second unused frequencies become used frequencies to the other plurality of wideband modems for selection.

11. The coaxial network of claim 5, wherein the wideband modem determines the first and second unused frequencies by requesting at least one other communicating modem to transmit a return signal at a particular unused frequency and analyzing the quality of the return signal.

12. The coaxial network of claim 11, wherein the quality of the return signal from the at least one other communicating modem is determined by at least one of an amplitude, signal to noise ratio, and bit error rate of the return signal.

13. The coaxial network of claim 11, wherein the wideband modem requests the return signal from the at least one other communicating modem using FSK communications.

14. The coaxial network of claim 11, wherein the wideband modem continues to request the at least one other communicating modem to transmit a return signal at numerous unused frequencies until an optimized first and second available frequency is determined.