WO2011162594A1

WO2011162594A1 - Method for use in mesh network based on 802.16j

Info

Publication number: WO2011162594A1
Application number: PCT/MY2011/000119
Authority: WO
Inventors: Md. Nazmus Saadat; Kee Ngoh Ting
Original assignee: Mimos Berhad
Priority date: 2010-06-22
Filing date: 2011-06-22
Publication date: 2011-12-29

Abstract

The present invention provides a method for use in a mesh network based on 802.16j Standard, whereby a direct communication between the relay station (RS) and the base stations (BS) and more particularly MR-BS in different cells can be attained.

Description

METHOD FOR USE IN MESH NETWORK BASED ON 802.16J FIELD OF INVENTION

The present invention relates to a method for facilitating in wireless mesh network, and more particularly a method for use in a multi hop wireless mesh network. BACKGROUND OF INVENTION

The urge to improve network capacity and thus provide high speed data transfer between mobile devices or components has been progressively demanding within the emergent world. An exemplary of the most prominent and reliable communication paradigms of this age is the wireless mesh network (WMN) , in which generally, this particular paradigm is developed to enable wireless interconnections between nodes, by means of remote information transmission. At present, wireless networking is commonly associated with multi-hop networking and mesh networking, in which for such network, information is conveyed or routed from a source to a destination using two or more networks. The efficiency in providing maximum data transfer between nodes as briefly discussed above plays a significant role in providing reliable data to users. However, in many cases data can only be transferred with the assistance of various intermediate components or devices particularly for mesh operations, whereby data travelling or transfer may become rather expensive.

It is further known among the experts of the field that the primary challenges in providing suitable and effect data throughput between nodes are to provide resilient, cost efficient and reliable connections for future generation networks . Following the above, IEEE 802.16j is part of an effort to create reliable data throughput whereby it is generally a wireless multi-hop network communication standard extended from IEEE 802.16e predominantly to improve network capacity and extend network coverage size by way of forming tree or network topologies using multi-hop relays approach. It is being reported that 802.16j defines relay station (RS) as a better technology in assisting base stations (BS) for solving challenges related to coverage extension or throughput enhancement issues. Nevertheless, the limitations of using 802.16j include the use of Access Service Network (ASN) and Connectivity Service Network (CSN) which are known to be costly in terms of BW usage, delay and longer path routing. This is typically the case when the Subscriber Station (SS) requires communication with other SS, within a same cell; the data and control would have to go through the ASN. And in the event that the SS requires communication with another SS which is located in another different cell, the said SS would have to go through an ASN and a CSN. Both of these operations are therefore pricey.

The main causative factor for the above described conditions is the fact that existing 802.16j standard does not provide or define any mesh topology among multi hop relay base station (MR-BSs) and thereby MR-BSs are not able to send data directly to other MR-BSs devoid of any assisting operations or the likes, for instance HO messages. Further, there have yet a defined network entry or procedures for inter linking of MR-BS mesh, as the standard at present solely defines the RS within the MR-BS cell. Current efforts to prevail over the shortcomings of the conventional methods and systems as discussed above, experts of the respective industry are constantly developing solutions to improve the network capacity for multi-hop networking.

An exemplary of an advancement to address the issues discussed in the preceding paragraph is as disclosed in US 7415, 278, entitled Method and System for creating and deploying a mesh network. This disclosure teaches the computer based method for providing a mesh router which is used in a cell from a plurality of cells that is adapted to cover a predetermined geographic region, whereby the mesh router includes at least three backhaul radios on different channels and one access radio. The gist of the disclosure is to permit channel re-use throughout the plurality of cells, by means of assigning a common channel based on the three different channels. Although this may be expedient relative to allowing communication based on a plurality of channels, the method reguires at least three radios for backhaul and at least one access radio. Again, this operation would be costly and routing path is rather extended . Based on the above, although the conventional approaches may be expedient in certain circumstances, great majorities of the said known approaches and methods in the art may not provide an effective solution in regards to latency and throughput.

Recognizing the aforementioned shortcomings, the present invention has been accomplished to provide an effective approach for addressing the common drawbacks related to 802.16j standards.

It is therefore the primary object of the present invention to provide an approach for providing reliable throughput within a network.

It is yet another object of the present invention to provide a method for use in allowing direct data transfer to another MR-BS devoid of any intermediate operations or components .

It is a further object of the present invention to provide a method for coupling approach among a plurality of MR-BSs using 802.16j based relay station to form MR-BS full mesh topology . These and other objects, features and advantages o f the present invention will be apparent from the following detailed description of preferred embodiments thereof.

SUMMARY OF INVENTION

The present invention discloses a method for use in a mesh network, said network comprising at least one relay station (RS) and at least two base station (BR) the method comprising the steps of: the relay station (RS) undergoing a first network entry process for acquiring a first access station; registering under the nearest base station; the relay station (RS) undergoing a second network entry process for acquiring a second access station; registering the second nearest base station as the second access station; coupling said first and second base stations to the relay station; configuring the relay station to be in simultaneous and transmit mode (STR) ; configuring the hop count relay station (RS) based on the MAC layer of the relay station (RS) . BRIEF DESCRIPTION OF THE DRAWINGS

The features, objects and advantages thereof may be best understood by reference to the following detailed description when read with accompanying drawings in which:

FIG 1 shows the standard method of communication between two subscriber stations (SS) in different cells;

FIG 2 shows the mesh topology in accordance with a preferred embodiment of the present invention;

FIG 3 shows the coupling of relay station with base stations respectively.

FIG 4 shows the method in accordance with a preferred embodiment of the present invention; FIG 5 shows the overall steps involved for method in accordance with a preferred embodiment of the present invention; FIG 6 shows the method with respect to a preferred embodiment of the present invention;

FIG 7 shows the pseudo code involved with respect to the method of the present invention.

DETAILED DESCRIPION OF THE PRESENT INVENTION

In addition to the drawings and in line with the summary of the invention, further understanding of the object, construction, characteristics and functions of the invention, a detailed description with reference to the embodiments is given in the following to understand the inventive features of the present invention. It shall be apparent to one skilled in the art, however that this invention may be practiced without such specific details. Some of the details may not be described at length so as not to obscure the invention. For ease of reference, common reference numerals will be used throughout the figures when referring to the same or similar features common to the figures . FIG 1 depicts the standard method of communication between two subscriber stations (SS) in different cells. As seen is the said drawing, relay stations (RS) can communicate directly to the respective MR-BS or other relay stations (RS) . However, in the event that the MR-BS is out of range relative to another MR-BS, these base stations would not have a direct radio link in between them. Therefore, communications are provided with the assistance of ASN and/or CSN as discussed briefly earlier.

The gist of the invention is to provide an interlink communication for transfer of data between two MR-BS with the aid of two or a pair of RSs. To achieve this based on 802.16j; the intermediate RSs are suitably configured to be in STR mode and adapted to undergo a modified network entry process in accordance with a preferred embodiment of the present invention.

FIG 2 and FIG 3 show the mesh topology in accordance with a preferred embodiment of the present invention and coupling of relay station with base stations respectively. FIG 4 depicts the network entry and initialization process for method used with respect to the present invention whilst FIG 5 shows the overall view of the steps involved with respect to the present invention, and more particularly the area in which the network entry and relay station (RS) coupling with the base station is shown. FIG 6 shows entry steps in accordance with the present invention, which will be configured for the relay station (RS) . Still referring to FIG 5 and FIG 6 the method of the present invention commences with the relay station (RS) undergoing the first network entry process until it gets registered under the nearest first R-BS. Subsequently, it would run network re-entry process in order to acquire a second stage access station. During this stage, the relay station therefore is configured to undergo a second network entry process and in the event that the RS successfully identified another MR-BS by way of neighbor scanning, the RS thereby assigns a second stage access based on the respective BS identification (48 bit unique MAC) . The RS later registers the second base station as the second access station. The pseudo code involved with respect to the method of the present invention is shown in FI G 7 .

Accordingly, the RS therefore stores at least two identification numbers, whereby at least one identification data is acquired for a first MR-BS and at least one identification data acquired for the second stage access MR-BS. With such condition there are two MR-BS connected or coupled to one RS .

From the above, the RS is then suitably configured to attain Simultaneous Transmit and Receive (STR) mode, preferably by using fixing bit in RS_Config-CMD . Suitably, the hop count of the RS thereby would be fixed to 2 hops based on the preferred embodiment of the present invention.

In another embodiment of the present invention, the method may include the step of rescheduling of radio resource if necessary and routing mechanism for the BS MAC. In addition, centralized scheduling algorithms and standard layer 2 routing algorithm may be used in accordance with another preferred embodiment of the present invention. From the foregoing, it would be appreciated that the present invention may be modified in light of the above teachings. It is therefore understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Claims

1. A method for use in a mesh network, said network comprising at least one relay station (RS) and at least two base station (BR) the method comprising the steps of: the relay station (RS) undergoing a first network entry process for acquiring a first access station;

registering under the nearest base station;

the relay station (RS) undergoing a second network entry process for acquiring a second access station; registering the second nearest base station as the second access station;

coupling said first and second base stations to the relay station;

configuring the relay station to be in simultaneous and transmit mode (STR) ;

configuring the hop count relay station (RS) based on the MAC layer of the relay station (RS) .

2. The method as claimed in Claim 1 wherein the method is for use based on 802.16] standard.

3. The method as claimed in Claim 1 wherein the method further comprising the step of scheduling of radio resource usage.

4. The method as claimed in Claim 1 wherein the method further comprising routing the base station MAC when necessary .

5. The method as claimed in Claim 1 to 4 wherein the method further includes using centralized scheduling algorithms and layer 2 routing algorithm.

6. The method as claimed in Claim 1 wherein the method further comprising the relay station (RS) storing both identification data for the first base station and second base station.

7. The method as claimed in Claim 1 wherein the second access stage step further comprising scanning the second nearest base station and acquiring the identification data of said base station.

8. The method as claimed in Claim 1 wherein the base station is a multi-hop relay base station (MR-BS)