Integrated infrastructure for coexistence of WI-FI networks with other networks

• US 8,081,996 B2
• Filed: 05/16/2006
• Issued: 12/20/2011
• Est. Priority Date: 05/16/2006
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Kolavennu, Soumitri N., Yi, Yunjung
• Primary Examiner(s): Appiah, Charles
• Assistant Examiner(s): Rideout, William F
• Application Number:
  US11/435,107
• Publication Number:
  US 20070268884A1
• Time in Patent Office: 2,044 Days
• Field of Search: 455/426.1, 455/504, 455/509, 455/447, 455/448, 455/450, 370/350
• US Class Current: 455/509
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 84/22 with access to wired networks
• CPC Class Codes: H04W 88/12 Access point controller devices

Abstract

A wireless communications method and system includes an industrial sensor network that comprises a plurality of industrial sensors, which communicates with the industrial sensor network at a particular operating frequency band through one or more infrastructure nodes associated with the industrial sensor network. A wireless communications network is established, which includes a plurality of wireless communications stations that communicates with one or more of the infrastructure nodes. The infrastructure node(s) can be modified to additionally function as a wireless access point for the wireless communications network utilizing Time Division Multiplexing Algorithm (TDMA), thereby permitting the industrial sensor network to coexist and accommodate the wireless communications network.

Claims

1. A wireless communications method, comprising:

providing a wireless network comprising a plurality of sensors that communicate with said wireless network at a particular operating frequency hopping spectrum through at least one infrastructure node associated with said wireless network, said wireless network further comprising 802.11 slots and non-802.11 slots;

establishing an integrated auxiliary wireless communications network comprising a plurality of wireless communications stations that communicate with said at least one infrastructure node;

transmitting an unsolicited CTS signal at an end of a time period from said at least one infrastructure node;

varying a power level of a transmission from said at least one infrastructure node;

and

modifying said at least one infrastructure node to additionally function as a wireless access point for said auxiliary wireless communications network, permitting said wireless network to coexist and accommodate said auxiliary wireless communications network, wherein modifying said infrastructure node comprises;

freezing transmission during said non-802.11 slots;

rejecting a Request to Send (RTS) if successive data transmissions are not accomplished before said 802.11 slot ends;

setting a timer for the end of said 802.11 slot and the start of a next 802.11 slot among said 802.11 slots; and

sending a beacon during said 802.11 slots utilizing a counting beacon timer.

2. The method of claim 1 further comprising providing a TDMA protocol to support said wireless network and said auxiliary wireless communications network.

3. The method of claim 1 wherein said time period comprises a predefined time period.

4. The method of claim 1 wherein said wireless network comprises an industrial sensor network.

5. The method of claim 1 wherein said auxiliary wireless communications network comprises a Wi-Fi network having a different security level than said wireless network.

6. The method of claim 5 wherein said wireless access point comprises a Wi-Fi access point.

7. The method of claim 4 further comprising:

permitting said industrial sensor network to communicate with said at least one infrastructure node utilizing a Frequency Hopping Spectrum mechanism.

8. The method of claim 4 further comprising:

permitting said industrial sensor network to communicate with said at least one infrastructure node utilizing an IEEE 802.15.4 ZigBee communications protocol.

9. The method of claim 1 further comprising:

permitting said wireless access point to communicate with said auxiliary wireless communications network utilizing an IEEE 802.11 communications protocol .

10. The method of claim 1 further comprising:

synchronizing a clock on said auxiliary wireless communications network side with said wireless network and said at least one infrastructure node to orchestrate communications in a TDMA manner.

11. An integrated wireless communications system, comprising:

a wireless network comprising a plurality of sensors that communicates with said wireless network at a particular operating frequency band through at least one infrastructure node associated with said wireless network, said wireless network further comprising 802.11 slots and non-802.11 slots;

a transmission mechanism for transmitting an unsolicited CTS signal at an end of a predefined time period from said at least one infrastructure node;

a power mechanism for varying a power of transmission in said at least one infrastructure node; and

an auxiliary wireless communications network comprising a plurality of wireless communications stations that communicates with said at least one infrastructure node at another operating frequency, wherein said at least one infrastructure node is modified to additionally function as a wireless access point for said auxiliary wireless communications network, thereby permitting said wireless network to coexist and seamlessly accommodate auxiliary said wireless communications network, wherein modifying said infrastructure node comprises;

freezing transmission during said non-802.11 slots;

rejecting a Request to Send (RTS) if successive data transmissions are not accomplished before said 802.11 slot ends;

setting a timer for the end of said 802.11 slot and the start of a next 802.11 slot among said 802.11 slots; and

sending a beacon during said 802.11 slots utilizing a counting beacon timer.

12. The system of claim 11 further comprising a TDMA protocol to support said wireless network and said auxiliary wireless communications network.

13. A wireless application network system comprising:

a plurality of industrial infrastructure nodes that acts as access points for a plurality of Wi-Fi stations, said plurality of Wi-Fi stations communicate with said plurality of infrastructure nodes;

a plurality of industrial sensors, wherein said plurality of industrial sensors communicate with said plurality of industrial infrastructure nodes, wherein said sensors and industrial infrastructure nodes utilize a globally synchronized clock;

a TDMA data structure utilized to implement a TDMA scheme that simultaneously supports a frequency hopping spread spectrum (FHSS) protocol and an IEEE 802.11 protocol;

a backoff timer associated with said TDMA scheme to allow transmission of a packet when said backoff timer expires;

said FHSS protocol supporting data transfer from at least one industrial sensor among said plurality of industrial sensors to at least one industrial infrastructure node among said plurality of industrial infrastructure nodes;

said IEEE 802.11 protocol supporting data transfer from at least one Wi-Fi station among said plurality of Wi-Fi stations to at least one access point among said access points; and

said TDMA scheme further comprising equally sized time frames, wherein each time frame among said equally sized time frames comprises a plurality of guard times, an FHSS slot, and a 802.11 slot, wherein an unsolicited CTS signal is transmitted at termination of said 802.11 slot, said unsolicited CTS signal having a Network Allocation Vector (NAV) duration equal to the sum of a FHSS slot size and twice the size of one of said plurality of guard times, and wherein a duration of said FHSS slot and said 802.11 slot is determined based on minimizing packet drops from said plurality of Wi-Fi stations, which is not aware of said FHSS slots, and allowing a sufficient time for said FHSS slot to satisfy bandwidth requirements of said plurality of industrial sensors.

14. The system of claim 13 wherein during said FHSS slot, said plurality of industrial infrastructure nodes behaves as a single industrial infrastructure node and during 802.11 slot said plurality of industrial infrastructure nodes behaves as said access points.

15. The system of claim 14 wherein said plurality of industrial sensors is configured to transmit data to said plurality of industrial infrastructure nodes only in an FHSS slot 43 of said FHSS slot and to enter a sleep mode in said 802.11 slot.