System and method for communicating using a plurality of TDMA mesh networks having efficient bandwidth use

• US 7,773,575 B2
• Filed: 07/24/2006
• Issued: 08/10/2010
• Est. Priority Date: 07/24/2006
• Status: Expired due to Fees

• Current Assignee: Stingray IP Solutions LLC (Acacia Research Corporation)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Rudnick, William M.
• Primary Examiner(s): RAMPURIA, SHARAD K
• Application Number:
  US11/459,384
• Publication Number:
  US 20080019298A1
• Time in Patent Office: 1,478 Days
• Field of Search: 370/338, 370/328, 370/458, 370/321, 370/347, 370/348, 370/350, 370/468, 455/41.2, 455/450
• US Class Current: 370/347
• CPC Class Codes: H04J 4/00 Combined time-division and frequency-division multiplex systems H04J13/00 takes precedence ; data transmission H04L5/26; telemetry G08C15/00
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

In accordance with a non-limiting example of the present invention, a communications system includes a plurality of Time Division Multiple Access (TDMA) mesh networks, each comprising a plurality of wireless nodes, each having a transmitter and receiver that communicate on a primary and at least one secondary frequency, and communicate using a TDMA epoch that is divided into at least a beacon interval using the primary frequency and a digital data interval using both the primary and secondary frequencies. The wireless nodes are operative for allocating a secondary frequency usage of a digital data interval for a TDMA mesh network to fall into an unused portion of the secondary frequency usage of another TDMA mesh network.

Claims

1. A communications system, comprising:

first and second Time Division Multiple Access (TDMA) mesh networks, each comprising a plurality of wireless nodes;

each node of the plurality of wireless nodes within respective first and second TDMA mesh networks comprising a transmitter and receiver that communicate on a primary and at least one secondary frequency and using a TDMA epoch that is divided into at least a beacon interval using the primary frequency and a digital data interval using both the primary and secondary frequencies, wherein said wireless nodes allocate an unused secondary frequency such that a digital data secondary frequency TDMA usage for the second TDMA mesh network falls into an unused portion of the secondary frequency usage map of the first TDMA mesh network, wherein a TDMA epoch for the second TDMA mesh network is offset from the start of a TDMA epoch for the first TDMA mesh network such that TDMA secondary frequency usage of the digital data interval for the second TDMA mesh network falls into an unused portion of the secondary frequency usage in the first TDMA mesh network.

2. The communications system according to claim 1, wherein the start of a TDMA epoch is maintained for at least first and second TDMA mesh networks in an overlapped condition.

3. The communications system according to claim 1, wherein said wireless nodes within the second TDMA mesh network create a phantom wireless node that hears wireless nodes within the first TDMA mesh network, whose start of a TDMA epoch is at a desired offset based upon an inferred start of a TDMA epoch.

4. The communications system according to claim 3, wherein said phantom wireless node is synchronized with other wireless nodes within the second TDMA mesh network.

5. The communications system according to claim 1, wherein said TDMA epoch is divided into a beacon interval, a digital voice interval and a digital data interval.

6. A method of communicating in a wireless mesh network, which comprises:

allocating a primary frequency and at least one secondary frequency within a first TDMA mesh network having a plurality of wireless nodes and communicating with each other using a TDMA epoch that is divided into at least a beacon interval using the primary frequency and digital data interval using both the primary and secondary frequencies;

allocating a primary frequency and at least one secondary frequency within a second TDMA mesh network and communicating with each other using a TDMA epoch that is divided into at least a beacon interval using the primary frequency and digital data interval using both primary and secondary frequencies; and

allocating an unused secondary frequency in the first TDMA mesh network such that a digital data secondary frequency TDMA usage for the second TDMA mesh network falls into an unused portion of the secondary frequency usage map of the first TDMA mesh network, and further comprising starting a TDMA epoch for the second TDMA mesh network offset from the start of the TDMA epoch for the first TDMA mesh network, wherein the secondary frequency usage of the digital data interval for the second TDMA mesh network falls in an unused portion of secondary frequency usage in the first TDMA mesh network.

7. The method according to claim 6, which further comprises allocating a new, unused frequency for the primary frequency of the second TDMA mesh network.

8. The method according to claim 6, which further comprises maintaining the start of TDMA epochs for the first and second TDMA mesh networks in an overlapped condition.

9. The method according to claim 6, which further comprises allocating a primary frequency and at least one secondary frequency within a third TDMA mesh network having a digital data interval on at least one secondary frequency, wherein the TDMA secondary frequency usage of the digital data interval falls in an unused portion of the secondary frequency usage of first and second TDMA mesh networks.

10. The method according to claim 6, which further comprises creating a phantom wireless node from wireless nodes within the second mesh network that hear wireless nodes within the first TDMA mesh network, whose start of a TDMA epoch is at a desired offset based upon an inferred TDMA mesh network start of a TDMA epoch.

11. The method according to claim 10, which further comprises creating the phantom wireless node when synchronizing the second TDMA mesh network.

12. The method according to claim 11, which further comprises establishing a plurality of phantom wireless nodes when synchronizing the second TDMA mesh network.

13. The method according to claim 6, which further comprises encountering a third TDMA mesh network such that TDMA secondary frequency usage for the third TDMA mesh networks falls in an unused portion of the first and second TDMA mesh networks that have been encountered.

14. The method according to claim 6, which further comprises dividing the TDMA epoch into a beacon interval, and optional digital voice interval and a digital data interval.

15. A method of communicating in a Time Division Multiple Access (TDMA) wireless mesh network, which comprises:

allocating a primary frequency and at least one secondary frequency within first and second TDMA mesh networks, each having a plurality of wireless nodes and communicating with each other using a TDMA epoch that is divided into at least a beacon interval using the primary frequency and a digital data interval using both the primary and secondary frequencies; and

allocating by the first TDMA network an unused secondary frequency such that a digital data secondary frequency TDMA usage for the second TDMA mesh network falls in an unused portion of the secondary frequency usage of the first TDMA mesh network, and further comprising starting a TDMA epoch for the second TDMA mesh network offset from the start of the TDMA epoch for the first TDMA mesh network, wherein the secondary frequency usage of the digital data interval falls in an unused portion of secondary frequency usage in the first TDMA mesh network.

16. The method according to claim 15, which further comprises allocating a new, unused frequency for the primary frequency of the second TDMA mesh network.

17. The method according to claim 15, which further comprises maintaining the start of TDMA epochs for first and second TDMA mesh networks in an overlapped condition.

18. The method according to claim 15, which further comprises creating a phantom wireless node from wireless nodes within the second TDMA mesh network that hears wireless nodes within the first TDMA mesh network, whose start of a TDMA epoch is at a desired offset based upon an inferred TDMA start of a TDMA epoch of the first TDMA mesh network.

19. The method according to claim 15, which further comprises creating the phantom wireless node when synchronizing the second TDMA mesh network.

20. The method according to claim 19, which further comprises establishing a plurality of phantom wireless nodes that are created when synchronizing the second TDMA mesh network.

21. The method according to claim 15, which further comprises dividing the TDMA epoch into a beacon interval, and optional digital voice interval and a digital data interval.