Method and apparatus of dynamic spectrum allocation in coexisting heterogeneous wireless networks

• US 20070281710A1
• Filed: 03/02/2007
• Published: 12/06/2007
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Bai, Yong, Chen, Lan, Hidetoshi, Kayama
• Granted Patent: US 7,894,821 B2
• Time in Patent Office: Days
• US Class Current: 455/452.100
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/04 Large scale networks; Deep hierarchical networks
• CPC Class Codes: H04W 84/10 Small scale networks; Flat hierarchical networks
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Embodiments of this disclosure include a method and apparatus of dynamic spectrum allocation in coexisting heterogeneous wireless networks. A Mobile Station (MS) detects its own serving Access Point (AP) and a coexisting AP (cAP) of the serving AP, sends to the serving AP a service request message carrying a bandwidth demand and a cAP ID. The serving AP sends to a Dynamic Spectrum Allocation Module (DSAM) a spectrum request message carrying its own AP ID, the cAP ID and the spectrum demand. The DSAM allocates the spectrum dynamically using a dynamic spectrum allocation algorithm according to the spectrum demand, AP ID and cAP ID, and sends a spectrum allocation result to the serving AP, which allocates an appropriate bandwidth to the MS according to the spectrum allocation result. Thus, sharing spectrum dynamically between multiple coexisting wireless networks can be achieved, and spectrum utilization can be improved.

Claims

1. A method of dynamic spectrum allocation in coexisting heterogeneous wireless networks, comprising:

detecting, by a Mobile Station (MS), a serving Access Point (AP) for the MS and a coexisting AP (cAP) of the serving AP, acquiring a cAP Identifier (ID) of the cAP, and sending to the serving AP a service request message containing the cAP ID and a bandwidth demand;

upon receiving the service request message, sending, by the serving AP, to a Dynamic Spectrum Allocation Module (DSAM), a spectrum request message containing an AP ID of the serving AP, the cAP ID and a spectrum demand of the serving AP acquired according to one or more service request messages sent by the MS;

allocating, by the DSAM, spectrum dynamically using a dynamic spectrum allocation algorithm according to the AP ID, the cAP ID and the spectrum demand obtained, and sending a spectrum allocation result to the serving AP; and

allocating, by the serving AP, an appropriate bandwidth to the MS according to the spectrum allocation result from the DSAM.

2. The method of claim 1, wherein the process of sending the spectrum request message comprises:

upon receiving one service request message, sending, by the serving AP, to the DSAM the spectrum request message corresponding to the service request message received.

3. The method of claim 1, wherein the process of sending the spectrum request message comprises:

upon receiving multiple service request messages, combining, by the serving AP, the multiple service request messages, and sending one aggregate spectrum request message to the DSAM.

4. The method of claim 3, wherein the serving AP determines when to send the spectrum request message according to at least one of a preset threshold of the spectrum demand and a preset time interval of the spectrum request message.

5. The method of claim 1, wherein the process of allocating, by the DSAM, the spectrum dynamically comprises:

obtaining the spectrum demand, the AP ID and the cAP ID from the spectrum request message received;

searching, according to the AP ID, for a Spectrum Allocation Table (SAT) stored in the DSAM corresponding to the AP ID;

if there is no SAT for the AP ID, establishing an SAT corresponding to the AP ID with an initial spectrum allocated for the serving AP of the MS as 0;

searching, in the SAT, for a spectrum allocation record corresponding to the cAP ID;

if there is no entry for the cAP ID in the SAT, adding a spectrum allocation record corresponding to the cAP ID in the SAT, with initial spectrum allocated for the cAP of the serving AP as 0;

obtaining, from the spectrum allocation record, the initial spectrum allocated for the serving AP and the initial spectrum allocated for the cAP, and obtaining the spectrum demand of the serving AP and a spectrum demand of the cAP according to the spectrum request message;

determining whether a sum of the spectrum demand of the serving AP and the spectrum demand of the cAP is greater than total spectrum that can be shared;

if the sum is greater than the total spectrum that can be shared, performing dynamic spectrum congestion resolution;

otherwise, if the sum is not greater than the total spectrum that can be shared, allocating an appropriate spectrum for the serving AP according to the spectrum demand of the serving AP; and

updating the spectrum allocation record in the SAT according to the spectrum allocation result.

6. The method of claim 5, wherein the dynamic spectrum congestion resolution comprises a priority-based spectrum allocation, which comprises satisfying a spectrum request with a higher priority first.

7. The method of claim 5, wherein the dynamic spectrum congestion resolution comprises a reservation-based spectrum allocation, in which

during the process of allocating the spectrum dynamically, the spectrum that is obtained by a first AP of a coexisting Radio Access Technology (RAT) with reserved spectrum Nrev is a minimal value between the reserved spectrum Nrev and a spectrum demand of the first AP, and the spectrum obtained by a second AP of a coexisting RAT without reserved spectrum is a minimal value between a spectrum demand of the second AP and the difference between the total spectrum and the spectrum actually obtained by the first AP.

8. The method of claim 7, wherein the reserved spectrum preset for the coexisting RAT is determined by a criterion designed according to at least one of a spectrum outage probability and the total revenue obtained from the coexisting RAT.

9. The method of claim 5, wherein the process of performing the dynamic spectrum congestion resolution comprises:

performing the dynamic spectrum congestion resolution according to spectrum allocation probabilities preset for each coexisting RAT.

10. The method of claim 9, wherein the spectrum allocation probabilities preset for each coexisting RAT are determined by a criterion designed according to the spectrum outage probability and/or the total revenue obtained from the coexisting RAT.

11. The method of claim 5, further comprising:

allocating spectrum for an AP of a coexisting RAT in advance;

before the process of determining whether the sum of the spectrum demand of the serving AP and the spectrum demand of the cAP is greater than the total spectrum that can be shared,

if the spectrum demand of the serving AP is less than or equal to the spectrum allocated in advance, allocating, by the serving AP, the appropriate bandwidth for the MS requesting the spectrum, and performing the process of updating the spectrum allocation record in the SAT according to the spectrum allocation result;

otherwise, performing the process of determining whether the sum of the spectrum demand of the serving AP and the spectrum demand of the cAP is greater than the total spectrum that can be shared.

12. The method of claim 1, further comprising:

reallocating the spectrum for the MS when the cAP changes because the MS moves.

13. The method of claim 12, wherein the process of reallocating the spectrum comprises:

determining whether the sum of the spectrum demand of the serving AP of the MS and the spectrum demand of the cAP is greater than the total spectrum that can be shared;

if the sum is greater than the total spectrum that can be shared, performing the dynamic spectrum congestion resolution;

otherwise, allocating the appropriate spectrum for the serving AP according to the spectrum demand of the serving AP; and

updating the spectrum allocation record in the SAT according to the spectrum allocation result.

14. The method of claim 1, further comprising:

when allocating the spectrum in the scale of sectors in the serving AP of the RAT, detecting, by the MS, a sector ID and carrying the sector ID in the service request message;

maintaining, by the DSAM, an SAT corresponding to a sector;

wherein the spectrum is allocated differently between coexisting heterogeneous wireless networks in each sector of the serving AP.

15. An apparatus of dynamic spectrum allocation, comprising:

a spectrum request processing module, to receive spectrum request messages from Access Points (AP) of Radio Access Technologies (RATs), and obtain, from the spectrum request messages, parameters related to a spectrum request;

a Spectrum Allocation Table (SAT) storing module to store a spectrum allocation record corresponding to a serving AP and a coexisting AP (cAP) of a RAT;

a dynamic spectrum allocation module, connected to the spectrum request processing module and the SAT storing module, to allocate spectrum dynamically using a dynamic spectrum allocation algorithm through searching for the spectrum allocation record stored in the SAT storing module according to the parameters related to the spectrum request from the spectrum request processing module;

a spectrum allocation result output module, connected to the dynamic spectrum allocation module, to output a dynamic spectrum allocation result from the dynamic spectrum allocation module to the AP sending the spectrum request message.

16. The apparatus of claim 15, wherein the apparatus of dynamic spectrum allocation communicates with the serving AP and the cAP in a wired or wireless manner.

17. The apparatus of claim 15, wherein the SAT storing module is for maintaining an SAT corresponding to a sector of the serving AP in the RAT;

the dynamic spectrum allocation module is for allocating the spectrum in each sector between RATs;

the spectrum allocation result output module is for reporting a spectrum allocation result in each sector of the serving AP.