Wireless LAN architecture for integrated time-critical and non-time-critical services within medical facilities

• US 6,659,947 B1
• Filed: 07/13/2000
• Issued: 12/09/2003
• Est. Priority Date: 07/13/2000
• Status: Expired due to Term

• Current Assignee: GE Medical Systems Information Technologies Incorporated (GE Healthcare Technologies, Inc.)
• Original Assignee: GE Medical Systems Information Technologies Incorporated (GE Healthcare Technologies, Inc.)
• Inventors: Hannah, Stephen E., Carter, Scott J., Flanders, Edward L.
• Primary Examiner(s): Hindenburg, Max F.
• Assistant Examiner(s): ASTORINO, MICHAEL C
• Application Number:
  US09/615,362
• Time in Patent Office: 1,244 Days
• Field of Search: 600/300-301, 128/903-904, 128/920-925, 705/2-4, 705/9-10, 709/200-217, 709/223, 702/19, 379/106--10, 340/573.1, 340/870-1-8
• US Class Current: 600/300
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: G06Q 40/08 Insurance
• CPC Class Codes: G16H 10/65 stored on portable record carriers, e.g. on smartcards, RFID tags or CD
• CPC Class Codes: G16H 40/20 for the management or administration of healthcare resources or facilities, e.g. managing hospital staff or surgery rooms
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 74/02 Hybrid access
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y10S 128/903 Radio telemetry
• CPC Class Codes: Y10S 128/904 Telephone telemetry
• CPC Class Codes: Y10S 128/92 Computer assisted medical diagnostics

Abstract

A wireless local area network (WLAN) system comprises multiple access points that are distributed throughout a medical facility to provide wireless access to a hardwired network. The access points implement multiple WLAN protocols, including a realtime protocol for realtime patient monitoring (telemetry) and a standard WLAN protocol (such as IEEE 802.11 within an ISM band) for providing general-purpose wireless access. Some or all of the access points preferably implement both WLAN protocols such that the different WLANs and wireless device types share network access resources. Some or all of the access points may also include RF location-tracking modules which may be used to track locations of patients, hospital personnel, capital equipment, and/or disposable medical supplies. Also disclosed are an antenna design which may be used with the access points to improve reception (particularly for patient monitoring), and a TDMA timeslot rotation method for avoiding lockstep interference between access points that operate on the same channel.

Claims

1. A system for supporting both realtime and non-realtime wireless access to a hardwired computer network with a medical facility, comprising:

a plurality of access points connected to the hardwired network to provide wireless access to the hardwired network, the access points distributed throughout regions of the medical facility, wherein at least some of the access points implement a realtime wireless local area network (WLAN) protocol to transfer time-critical data from wireless devices to the hardwired network with a known maximum latency in real time, and wherein at least some of the access points implement a non-realtime WLAN protocol to provide general purpose wireless access to the hardwired network, and wherein at least one of the access points is a multi-protocol access point that implements both the realtime WLAN protocol and the non-realtime protocol; and

a plurality of wireless patient transceivers which implement the realtime WLAN protocol to transfer realtime patient data to the hardwired network in real time via the access points which implement the realtime WLAN protocol;

wherein the realtime WLAN protocol is a wireless TDMA protocol and the non-realtime protocol is an IEEE 802.11 WLAN protocol.

2. The system of claim 1, wherein the access points implement the realtime WLAN protocol within a first frequency band, and implement the non-realtime WLAN protocol in a second frequency band which is separate from the first frequency band.

3. The system of claim 2, wherein the first frequency band is a WMTS band and the second frequency band is an ISM band.

4. The system of claim 1, wherein the multi-protocol access point comprises a first transceiver which implements the realtime WLAN protocol and a second transceiver which implements the non-realtime WLAN protocol.

5. The system of claim 4, wherein the first transceiver operates in a first frequency band, and the second transceiver operates in second frequency band which is separate from the first frequency band.

6. The system of claim 5, wherein the first frequency band is a WMTS band and the second frequency band is an ISM band.

7. The system of claim 4, wherein the second transceiver is an IEEE 802.11 transceiver which operates in an ISM band.

8. The system of claim 7, wherein the second transceiver is contained within a PCMCIA card.

9. The system of claim 4, wherein the first transceiver is contained within a PCMCIA card.

10. The system of claim 1, wherein at least some of the access points include location tracking modules which use RF signals transmitted by object tracking devices to track object locations.

11. The system of claim 10, further comprising a software application which uses the location tracking modules and object tracking devices to track locations of capital equipment.

12. The system of claim 10, further comprising a software application which uses the location tracking modules and object tracking devices to track locations of disposable medical supplies.

13. The system of claim 10, further comprising a software application which uses the location tracking modules and object tracking devices to track locations of patients.

14. The system of claim 1, wherein at least two of the access points implement the realtime WLAN protocol on a common channel and use a timeslot dithering method to avoid lockstep interference.

15. The system of claim 1, wherein at least one of the access points implements the realtime WLAN protocol using an elliptical polarization antenna mounted with the predominant axis roughly vertical.

16. The system as in claim 15, wherein the antenna is further characterized by either an omni-directional or a bi-lobed azimuth pattern.

17. The system as in claim 1, further comprising a wireless access point which communicates with the hardwired network via a hardwired access point.

18. An access point for providing wireless access to a hardwired network of a medical facility, comprising:

a first transceiver module which implements a realtime wireless local area network (WLAN) protocol to transfer time-critical data in real time to the hardwired network with a known maximum latency; and

a second transceiver module which implement a non-realtime WLAN protocol to provide non-realtime wireless access to the hardwired network;

wherein the realtime WLAN Protocol is a wireless TDMA protocol and the non-realtime protocol is an IEEE 802.11 WLAN protocol.

19. The access point of claim 18, further comprising a wireless patient transceiver which transmits realtime patient data to the first transceiver module.

20. The access point as in claim 18, wherein the first transceiver module operates in a WMTS band, and the second transceiver operates in an ISM band.

21. A system for providing wireless connectivity within a medical facility, comprising:

a hardwired computer network;

at least one multi-protocol access point connected to the hard-wired computer network to provide wireless access to the hardwired computer network, the multi-protocol access point comprising a first radio frequency (RF) transceiver that operates according to a first wireless local area network (ELAN) protocol and a second RF transceiver that operates according to a second WLAN protocol;

a plurality of remote transceiver devices that communicant with the first RF transceiver according to the first WLAN protocol to convey real time physiologic data of patients to the hardwired computer network in real time; and

a plurality of wireless computing devices that communicate with the second RF transceiver according to the second WLAN protocol to access at least one non-realtime application running on the hardwired computer network;

wherein the first WLAN protocol is a wireless TDMA protocol and the second WLAN protocol is an IEEE 802.11 WLAN protocol.

22. The system as in claim 21, wherein the first RF transceiver operates in a WMTS band, and the second transceiver operates in an ISM band.

23. The system as in claim 21, wherein the second WLAN protocol is a CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) protocol.

24. The system as in claim 21, wherein the plurality of wireless computing devices include at least one of the following:

personal digital assistant devices, laptop computers, writing tablets.

25. The system as in claim 21, wherein the plurality of wireless computing devices include pagers.

26. The system as in claim 21, wherein the plurality of wireless computing devices include point-of-care data input devices.

27. The system as in claim 21, wherein the at least one non-realtime application comprises at least one of the following:

a hospital information system (HIS) application, a clinical information system (CIS) application.

28. The system as in claim 21, wherein the plurality of remote transceiver devices includes ambulatory transceiver devices worn by patients.

29. The system as in claim 21, wherein the hardwired computer network comprises a first LAN used for realtime patient monitoring and a second LAN used for non-realtime applications.