KR20090012545A - Channel scanning and allocation scheme for using multi-channel dls - Google Patents

Abstract

A communications method between stations through the channel search of DLS multichannel manager for improving the usability of link is provided to improve link utilization by setting up DLS(Direct-Link Setup) by using a dedicated channel. A DLS request message is delivered to AP in a source STA requesting CLS connection. The reserved bit of QoS capability field is used for informing DLS establishment. It shows to use the dedicated channel if the reserved bit is set as 1. It inspects whether the DLS request message requests the dedicated channel. When the dedicated channel is demanded, the usable DLS dedicated channel number is requested to the DLS multi-channel manager.

Description

Channel scanning and allocation scheme for using multi-channel in DLS environment {Channel scanning and allocation scheme for using multi-channel DLS}

The present invention relates to a technique using a DLS multi-channel manager that provides peripheral channel search, allocation, and communication functions to use the DLS (Direct-Link Setup) proposed in IEEE 802.11e as a dedicated channel. The multi-channel manager can be used to search for and allocate available channels efficiently, and in the DLS environment that can communicate with the BSS channel during transmission DLS channel using HCCA (HCF Controlled Channel Access) and DLS. A device and method for searching and assigning channels for using a channel.

DLS allows direct data transmission to STA-to-STA without passing through the AP when transmitting data between two STAs belonging to the same BSS in infrastructure mode.

In other words, about twice as much transmission gain as when not using DLS.

IEEE 802.11e defines DLS connection establishment and release procedures in the standard to use DLS.

The DLS connection procedure is initiated by sending a DLS request message from the source STA to the AP. The source STA wanting the DLS connection transfers the address of the destination STA and available WLANs physical layer information in the DLS request message to the AP.

After receiving the DLS request message, the AP determines the various conditions and delivers the DLS request message to the destination STA when the conditions are satisfied.

If the condition is not satisfied, the reason for connection failure is sent to the source STA in the DLS response message.

The conditions to check when the AP receives the DLS request message are: Does the AP provide the DLS function, is the destination STA currently registered in the BSS, or does the destination STA support the DLS function? to be.

After receiving the DLS request message by satisfying the condition at the AP, the source STA determines whether to accept the DLS connection request, and transfers the result to the DLS response message to the AP. Upon receiving the DLS response message, the AP forwards it back to the source STA. After receiving the DLS response message, the source STA determines whether the connection is established successfully and, when the connection is successfully executed, starts the data transmission using the DLS.

When using DLS using the same channel as BSS, the transmission gain is about twice that of non-DLS. However, if data transmission between DLS STA is frequent after establishing DLS connection, it is more beneficial to allocate and transmit DLS dedicated channel than to transmit with other STA using BSS channel.

However, in order to allocate a dedicated channel to the DLS, it is necessary to solve problems such as a method of searching and assigning a channel that can be used in addition to the BSS channel, a method of receiving data from the AP or a method of transmitting data to the AP when transmitting data using the dedicated channel.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a peripheral channel search, allocation and communication function to use the DLS (Direct-Link Setup) proposed in IEEE 802.11e as a dedicated channel. The DLS multi-channel manager can be used to search for and allocate available channels efficiently, and can also communicate with the BSS channel during transmission DLS channel using HCCA (HCF Controlled Channel Access) and DLS. An apparatus and method for channel searching and allocation for using multiple channels in an environment are provided.

In order to achieve the object of the present invention as described above, an embodiment of the channel search and allocation device for using multiple channels in the DLS environment according to the present invention, the source STA for sending a "DLS request message"; And a DLS multi-channel indicating a DLS configuration without a dedicated channel when the reserved bit is set to “1” using a reserved bit in the “QoS Capability” field when a DLS connection is requested. It is composed of manager module and performs channel search and allocation method to use multiple channels in DLS environment.

Another embodiment of a channel searching and allocating apparatus for using multiple channels in a DLS environment according to the present invention includes: an AP receiving a “DLS request message”; And a DLS multi-channel manager module for requesting available channel information upon receiving a DLS connection request message from the AP and then transmitting the channel information in a DLS request message payload when successfully assigning a dedicated channel to a destination STA. A channel search and allocation method for using a channel is performed. Here, the DLS multi-channel manager uses the data structure as shown in FIG. 6 to maintain available channel information, and the DLS multi-channel manager manages data according to the approval and release of the dedicated channel DLS as shown in FIG. 6.

Another embodiment of an apparatus for searching and allocating a channel for using multiple channels in a DLS environment according to the present invention includes: a destination STA for receiving a “DLS request message”; And a DLS multi-channel manager module configured to distinguish whether or not to set up a dedicated channel DLS connection by using a reserved bit of a "QoS Capability" field when receiving a DLS connection request, and searching for a channel to use multiple channels in a DLS environment. And an assignment method. Here, the DLS multi-channel manager module reserves the HCCA resource by using TSPEC when the dedicated channel DLS connection is established, and is used when transmitting or receiving data to the AP, and assigns the channel number assigned when transmitting the DLS response message to the DLS response message payload Create and send.

Another embodiment of an apparatus for searching and assigning a channel for using multiple channels in a DLS environment according to the present invention includes: an AP for receiving a “DLS response message”; And a DLS multi-channel manager module that notifies the DLS multi-channel manager of the final use of the channel when a dedicated channel DLS connection is successfully performed, and performs a channel search and allocation method for using multiple channels in a DLS environment. .

Another embodiment of an apparatus for searching and assigning a channel for using multiple channels in a DLS environment according to the present invention includes: a source STA that receives a “DLS response message”; And a DLS multi-channel manager module that is used for HCCA resource reservation, data transmission or reception to AP using TSPEC when a dedicated channel DLS connection is successfully established, and a channel search and allocation method for using multiple channels in a DLS environment. Perform.

Another embodiment of an apparatus for searching and allocating a channel for using multiple channels in a DLS environment according to the present invention includes: a QSTA receiving an HCCA polling message from a QAP; And a DL-HCCA manager module for distinguishing whether the received HCCA polling message is a polling message for DLS using a TSID and a TCLASS, and performs a channel search and allocation method for using multiple channels in a DLS environment.

Another embodiment of a channel searching and allocating apparatus for using multiple channels in a DLS environment according to the present invention is to switch to a BSS channel at the start of a next beacon when receiving or transmitting data to a BSS during transmission of a dedicated channel DLS data, HCCA Method of searching and allocating channel for using multi-channel in DLS environment, including DLS multi-channel manager module which starts DLS communication when communicating with AP and receiving contention free period from AP. Do this.

According to the present invention as described above, it is possible to obtain a very improved link utilization by setting the DLS using a dedicated channel, and the available channel search and allocation scheme for this can be efficiently performed using the DLS multi-channel manager. All. In addition, using the method using the HCCA proposed in the present invention among the communication using the dedicated channel DLS can bring the advantage that can also communicate with the existing BSS AP, STA.

Hereinafter, with reference to the accompanying drawings an embodiment of the present invention will be described in more detail.

The DLS multi-channel manager proposed in the present invention is located in a server capable of communicating with an access point (AP), and manages channels of various APs to use DLS using a dedicated channel.

STA (Station) to communicate by using a dedicated channel in the DLS delivers a DLS connection request message to the AP, the AP receives the request to the DLS multi-channel manager requests an additional channel for the DLS.

The DLS multi-channel manager periodically manages channel information about neighboring APs and DLS channels that are already allocated.

Upon receiving the channel assignment request, the DLS multi-channel manager checks the assignable channels and notifies the AP of the result. The AP notified of the channel allocation result transmits the channel allocation failure in the DLS response message to the source STA when the channel allocation fails.

If the channel allocation is successful, the allocated channel number is delivered to the destination STA by the DLS request message. After receiving the DLS request message, the destination STA determines whether to accept the multi-channel DLS and transfers the result to the DLS response message to the AP. Upon receiving the DLS response message, the AP delivers the result to the source STA. After the multi-channel DLS connection is successful, the destination STA and the source STA request resource allocation from the AP to use the HCCA using the TSPEC, and the AP transmits all data destined for the source STA and the destination STA using the HCCA.

Figure 1 shows the overall scenario, the DLS multi-channel manager manages the channels of the AP registered in advance. 2 shows a channel search and allocation procedure proposed in the present invention.

First, the source STA requesting the DLS connection transmits a DLS request message to the AP. At this time, the reserved bit of the "QoS Capability" field is used to inform the DLS configuration using the dedicated channel as shown in FIG. Setting the reserved bit to “1” indicates that the dedicated channel is used. If the reserved bit is set to “0”, the DLS configuration is shown without the dedicated channel.

Upon receiving the DLS request message, the AP performs an operation as shown in FIG. 4.

First, it checks whether the currently received DLS request message requires a dedicated channel.

If you do not require a dedicated channel, follow the DLS connection setup procedure outlined in the standard. If a private channel is required, request the available DLS dedicated channel number from the DLS multi-channel manager. At this time, if the channel is not allocated from the DLS multi-channel manager, the cause of DLS setting is marked in the "reason field" and the DLS response message is transmitted to the source STA.

If the channel is successfully allocated, the allocated channel is recorded in the payload portion of the DLS request message and transmitted to the destination STA.

The destination STA receiving the DLS request message acts as shown in FIG. 5. First check whether the currently received DLS request message requires a dedicated channel. At this time, whether the dedicated channel is used or not also uses the reseverd field of the "QoS capability" field.

If a dedicated channel is not required, follow the DLS connection setup procedure defined in the standard. If the DLS setting using the dedicated channel is requested, acceptance is determined. If the DLS is rejected using the dedicated channel, the AP informs the AP after marking the reason code for rejection in the DLS response message. If the channel is accepted, the AP informs the AP after marking the connection reason code in the DLS response message. At this time, the DLS response message is transmitted to the AP, and the HCCA resource is allocated between the destination STA and the AP using the TSPEC. This is used for receiving data from the AP or vice versa. After the HCCA resource is reserved, the channel is switched to the DLS dedicated channel and the DLS communication is prepared.

Upon receiving the DLS response message, the AP checks the result of the DLS connection establishment. If the dedicated channel DLS connection is successfully established, it informs the DLS multi-channel manager that the allocated channel is finally used and delivers the received DLS response message to the source STA. Upon receiving the DLS response message, the source STA checks the result of the dedicated channel connection request and, if the connection is established successfully, reserves the HCCA resource using TSPEC and switches to the DLS dedicated channel to start DLS communication.

The format shown in FIG. 6 is used to manage the list of channels available in the DLS multi-channel manager. In the DLS multi-channel manager, the data structure of FIG. 6 is configured for each dedicated channel DLS, and BSS information adjacent to the dedicated channel is maintained in a list form.

When receiving data from the AP or transmitting data when transmitting data using the dedicated channel DLS, the method as shown in FIG. 7 is proposed in the present invention. First, the source STA and the destination STA transmit data using a dedicated channel after establishing the DLS connection. Transmit data using dedicated channel and switch back to BSS channel before beacon message occurs. Since the beacon message is periodically generated from the AP, the next beacon generation time can be predicted. After switching to the BSS channel, it receives a beacon message and receives or transmits data from the AP according to the HCCA polling message. After notifying the end of the contention free period from the AP, it switches back to the DLS channel and resumes DLS communication.

The apparatus and method for searching and allocating a channel for using multiple channels in a DLS environment according to the present invention described above is not limited to the above-described embodiments, and without departing from the gist of the present invention as claimed in the following claims. Anyone with ordinary knowledge in the field of the invention has the technical spirit to the extent that it can be variously modified and implemented.

1 is a diagram showing the configuration of an entire network according to the present invention;

2 is a view showing a dedicated channel DLS connection procedure in the present invention.

3 is a format used to distinguish a dedicated channel DLS connection request in the present invention.

4 is a diagram illustrating an operation process in an AP receiving a DLS request message according to the present invention.

5 is a diagram illustrating an operation process in a destination STA receiving a DLS request message according to the present invention.

FIG. 6 is a diagram illustrating a data structure of a DLS multi-channel manager configuring channel information in the present invention. FIG.

7 is a view showing an operation of communicating with the BSS channel of the dedicated channel DLS communication in the present invention.

Claims (2)

In order to use the DLS (Direct-Link Setup) proposed by EEE 802.11e as a dedicated channel, it is possible to efficiently search for and allocate available channels using the DLS multi-channel manager, which provides peripheral channel search, allocation and communication functions. And a channel search and allocation apparatus for using multiple channels in a DLS environment that can communicate with a BSS channel during transmission DLS channel using HCCA controlled channel access (HCCA) and DLS. In order to use the DLS (Direct-Link Setup) proposed by EEE 802.11e as a dedicated channel, it is possible to efficiently search for and allocate available channels using the DLS multi-channel manager, which provides peripheral channel search, allocation and communication functions. And a channel search and allocation method for using multiple channels in a DLS environment that can communicate with a BSS channel during transmission DLS channel using HCCA (HCF Controlled Channel Access) and DLS.

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