METHOD FOR FAST LINK LAYER HANDOFF IN HETEROGENEOUS NETWORKS

• US 20130022022A1
• Filed: 03/15/2011
• Published: 01/24/2013
• Est. Priority Date: 04/06/2010
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Schmitt, Ruediger
• Granted Patent: US 10,159,020 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0066 of control information between different types of networks in order to establish a new radio link in the target network
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

When handing off a multi-mode patient monitoring device (PMD) (28) between radio access technology (RAT) networks, a serving access point (AP) (12, 16, 72) with which a communication link is established by the PMD (28) over a first RAT network (RAT-1) to permit the PMD to communicate with a hospital IP network (18) via the serving AP (12, 16, 72). A scanning interface (14, 54, 74, 104) collects information regarding other available RAT networks (e.g., RAT-2, RAT-3, etc) and candidate APs therein. If the RAT-1 communication quality of service falls below a predetermined threshold level, the serving AP (12, 16, 72) delivers information regarding the candidate APs (22, 24, 26) and their RAT networks to the PMD (28). Delivery of the candidate network/AP information is performed using a beacon signal continuously or periodically emitted from the serving AP (12, 16, 72), or upon request by the PMD (28). The PMD (28) selects a candidate AP (22, 24, 26) as a target AP, and initiates a handover to the target AP. In this manner, the PMD (28) is provided with candidate AP information without having to actively search for the APs, thereby conserving battery power.

Claims

1. A method of transferring a patient monitoring device between radio access technology (RAT) networks, comprising:

establishing a first communication link between a multi-mode patient monitoring device and a first access point over a first RAT network (RAT-1), wherein the patient monitoring device communicates with a hospital Internet protocol (IP) network via the first access point;

collecting information regarding one or more other candidate networks (RAT-2) over which the patient monitoring device is capable of communicating with the hospital IP network;

transmitting the candidate network information to the patient monitoring device; and

establishing a second communication link between the patient monitoring device and a second access point for a target network.

2. The method according to claim 1, wherein the RAT-1 network and the RAT-2 network respectively employ different radio access communication protocols.

3. The method according to claim 1, wherein the collected information includes quality of service information comprising one or more of signal quality information, bandwidth availability information, and link reliability information, and wherein only networks having access points providing a quality of service better than a quality of service for the first communication link are selected as candidate networks.

4. The method according to claim 1, wherein the first access point is a multi-mode access point capable of communicating over at least two different RAT networks.

5. The method according to claim 1, wherein the first access point is a single-mode access point capable of communicating over the first RAT network (RAT-1), and further comprising:

pairing the single-mode access point with a scanning device that collects the information regarding the one or more other candidate networks (RAT-2).

6. The method according to claim 1, further including storing candidate network information at in a database at one or more of:

the hospital IP network; and

the first access point.

7. The method of claim 1, wherein the collected candidate network information is transmitted to the patient monitor device using layer 2 frames adapted to carry the information, in response to a request from the patient monitoring device.

8. The method of claim 1, wherein the collected candidate network information is transmitted to the patient monitor device in a beacon signal emitted periodically from the access point.

9. A computer-readable medium carrying software for controlling a processor to configure and perform the method of claim 1.

10. A system that facilitates transferring a patient monitoring device between radio access technology (RAT) networks, comprising:

a multimode patient monitoring device (PMD) that establishes a first communication link between with a first access point over a first RAT network (RAT-1), over a first RAT network (RAT-1), wherein the patient monitoring device communicates with a hospital Internet protocol (IP) network via the first access point; and

a scanning interface configured to collect availability information regarding one or more candidate networks (RAT-2) over which the patient monitoring device is capable of communicating with the hospital IP network, wherein the scanning interface is located remotely from the multi-mode patient monitoring device;

wherein the first access point relays candidate network information from the scanning interface to the patient monitoring device.

11. The system according to claim 10, wherein the RAT-1 network and the RAT-2 network respectively employ different radio access communication protocols, and wherein the first access point communicates the candidate network information using the different radio access communication protocols.

12. The system according to claim 10, wherein the collected information includes quality of service information comprising one or more of signal quality information, bandwidth availability information, and link reliability information, and wherein the scanning interface selects as candidate networks only networks having access points providing a quality of service better than a quality of service for the first communication link.

13. The system according to claim 10, wherein the first access point is a multi-mode access point capable of communicating over at least two different RAT networks.

14. The system according to claim 10, wherein the first access point is a single-mode access point capable of communicating over the first RAT network (RAT-1), and wherein the scanning device is positioned in close proximity to the single-mode access point.

15. The system according to claim 10, further including storing candidate network information at in a database at one or more of:

the hospital IP network; and

the first access point.

16. The system according to claim 10, wherein the collected candidate network information is transmitted to the patient monitor device using layer 2 frames adapted to carry the information, in response to a request from the patient monitoring device.

17. The system according to claim 10, wherein the collected candidate network information is transmitted to the patient monitor device in a beacon signal emitted periodically from the first access point.

18. An apparatus that facilitates transferring a patient monitoring device between radio access technology (RAT) networks, comprising:

means for establishing and maintaining a first communication link using a first RAT network between a multi-mode patient monitoring device and a hospital Internet protocol (IP) network via the means for establishing and maintaining the first communication link;

means for collecting information regarding one or more candidate networks using a second radio access technology (RAT-2) over which the patient monitoring device is capable of communicating with the hospital IP network;

means for transmitting the candidate network information to the patient monitoring device;

means for establishing and maintaining a second communication link between the patient monitoring device and a second access point for the target network.

19. The apparatus according to claim 18, wherein the collected information includes quality of service information comprising one or more of signal quality information, bandwidth availability information, and link reliability information, and wherein only networks having access points providing a quality of service better than a quality of service for the first communication link are selected as candidate networks.

20. The apparatus according to claim 18, wherein the means for establishing and maintaining the first communication link is at least one of:

a multi-mode access point capable of communicating over at least two different RAT networks,

a single-mode access point capable of communicating over the first RAT network (RAT-1), with a scanning device that collects the information regarding the one or more other candidate networks (RAT-2);

wherein the collected information is transmitted to the patient monitor device in at least one of;

layer 2 frames adapted to carry the information, in response to a request from the patient monitoring device;

or

a beacon signal emitted periodically from the access point.