Infrared backbone communication network having a radio frequency backup channel

• US 5,880,867 A
• Filed: 01/21/1997
• Issued: 03/09/1999
• Est. Priority Date: 03/29/1996
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Ronald, Mahany L.
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US08/737,978
• Time in Patent Office: 777 Days
• Field of Search: 359/143.111, 359/145-146, 359/152, 359/167, 359/172, 455/73, 370/277, 370/310, 364/713
• US Class Current: 398/119
• CPC Class Codes: H04B 10/1149 Arrangements for indoor wireless networking of information
• CPC Class Codes: H04B 10/40 Transceivers

Abstract

A communication network which uses an infrared backbone and having a radio frequency backup channel is disclosed. The infrared backbone is generally located on a ceiling in a hallway of a building and comprises a plurality of hub access points. The hub access points communicate data on the backbone in a relay fashion using modulated infrared light. If infrared communications fail, the hub access points may, as a backup, communicate in the same fashion using low power radio frequency (RF) transmissions. In another embodiment, in an environment such as an airplane having equipment sensitive to RF noise, a communication network is installed having communication pathways which adapt in response to such equipment as need be to minimize RF noise. For example, high-bandwidth wired communicate on might be acceptable during some periods when the sensitive equipment is not in use. During other periods, the equipment may cause the communication pathways of the network to only utilize infrared transmissions or to enter an idle state. The access points use a sequential polling protocol and relay data throughout the network. Blocking and absorptive triangular shaped panels are used to absorb, deflect and contain infrared transmissions into cells

Claims

1. A communication network for maintaining communication among a plurality of end-point devices in an environment sensitive to RF interference, said network comprising:

a plurality of end-point devices;

a plurality of access point devices;

a communication pathway, comprising said plurality of access point devices, that supports communication among said plurality of end-point devices;

a device sensitive to RF interference;

a control link coupled to said device through which signals indicative of acceptable levels of RF interference are communicated;

said communication pathway being capable of generating different levels of RF interference; and

said communication pathway adjusting the level of RF interference generated based on the signals communicated via said control link.

2. The communication network of claim 1 further comprising a server responsive to said control link for relaying the signals indicative of acceptable levels of RF interference along said communication pathway.

3. The communication network of claim 2 wherein the server provides said plurality of end-point devices access to local and remote resources.

4. The communication network of claim 3 wherein the environment sensitive to RF interference constitutes an airplane, each of said plurality end-point devices constitutes a portable computer having an infrared transceiving pair, and said plurality of access points each have a plurality of infrared transceiver pairs disposed within the airplane to support communication with ones of the plurality of end-point devices.

5. A communication network for maintaining communication among a plurality of end-point devices in an environment sensitive to RF interference, the communication network comprising:

a communication pathway including a plurality of access point devices that supports communication among the plurality of end-point devices, the communication pathway being capable of generating different levels of RF interference;

a control link coupled to the communication pathway that provides an indication of acceptable levels of RF interference; and

the communication pathway adjusting the level of RF interference generated based on the indication from the control link.

6. The communication network of claim 5 further comprising a server responsive to the control link for relaying signals indicative of acceptable levels of RF interference along the communication pathway.

7. The communication network of claim 6 wherein the server provides the plurality of end-point devices access to local and remote resources.

8. The communication network of claim 7, the environment sensitive to RF interference constituting an airplane and each of the plurality end-point devices comprising a portable computer having an infrared transceiver pair, further comprising:

the plurality of access points each having a plurality of infrared transceiver pairs disposed within the airplane to support communication with ones of the plurality of end-point devices.

9. A communication network for providing communication among a plurality of end devices in an RF sensitive environment, comprising:

a backbone network;

a plurality of access points, coupled to the backbone network, that supports communication among the plurality of endpoint devices;

the plurality of access points and the backbone network being capable of operating at different levels of RF interference; and

a control link coupled to the backbone network to control operation of the backbone network and the level of RF interference.

10. The communication network of claim 9, further comprising:

each of the plurality of access points further coupled to at least one communication interface capable of enabling communication with one of the plurality of endpoint devices.

11. The communication network of claim 10, further comprising:

each communication interface communicating with the one of the plurality of endpoint devices using infrared communications.

12. The communication network of claim 11, each of the plurality end-point devices comprising a portable computer having an infrared transceiver pair, further comprising:

each communication interface comprising an infrared transceiver pair to support communication with a portable computer.

13. The communication network of claim 9, further comprising:

the plurality of access points communicating on the backbone network according to either one of a first protocol that produces a first level of RF interference and a second protocol that produces a second level of RF interference.

14. The communication network of claim 13, further comprising:

the first protocol utilizing wired links; and

the second protocol utilizing infrared links.

15. The communication network of claim 13, further comprising:

the control link causing the backbone network to switch between the first and second protocols based on the level of RF interference allowed.

16. The communication network of claim 15 further comprising an RF sensitive device coupled to the control link.

17. The communication network of claim 16 wherein the RF sensitive device further including a manual override to enable manual switching between the first and second protocols.

18. The communication network of claim 9 further comprising a server, coupled to the control link, that provides access to local and remote resources.