KR20120139001A

KR20120139001A - A reservation diversity method for distributed wimedia mac for ship area wimedia network

Info

Publication number: KR20120139001A
Application number: KR1020110058498A
Authority: KR
Inventors: 이연우; 김경성; 문민우; 허경; 이성로; 모귀환
Original assignee: 목포대학교산학협력단
Priority date: 2011-06-16
Filing date: 2011-06-16
Publication date: 2012-12-27

Abstract

PURPOSE: A wi-media resource reservation method for constructing a wi-media network is provided to reserve other links by passing through a relay device or a direct link. CONSTITUTION: When data is transmitted and received in an MAS(medium access slot) S-R(S518), a DRP(distributed reservation protocol) IE(information element) for a reservation target node set as a reservation detail state code of a relay notification is confirmed(S522). It is determined whether the data is transmitted and received through an MAS R-T(S524). When a relay node is able to use the MAS S-R and the MAS R-T, MAS R-T information for continuously transmitting the data is stored(S526). The DRP IE set as a relay approval reservation state code is transmitted to a reservation subject node(S528). [Reference numerals] (AA) Start; (BB,DD,FF,HH,JJ) No; (CC,EE,GG,II,KK) Yes; (LL) End; (S510) Receiving DRP IE from a reservation subject node; (S512) Reason Code == Relay Req?; (S514) Is extra power which is necessary for relay transmission existed?; (S516) Transmitting DRP IE(Reason Code == Denied) to a reservation subject node; (S518) Is data able to be transmitted and received in an MAS S-R section of DRP IE?; (S520) Transmitting DRP IE(Reason Code=Conflict) to a reservation subject node; (S522) Confirming DRP IE of a reservation target node(Reason Code==Relay Ntf) including the same stream index; (S524) Is data able to be transmitted and received in an MAS R-T section of DRP IE?; (S526) Storing MAS R-T information for relay transmission; (S528) Transmitting DRP IE(Reason Code== Relay Accepted) to a reservation subject node; (S530) Is a reservation target node matched with DRP IE(Reason Code==Relay Accepted) transmitted to a reservation subject node?; (S532) Relaying received packets to a reservation target node according to MAS R-T information stored by receiving packets during MAS S-R; (S534) Deleting reservation information of MAS S-R and MAS R-T

Description

A reservation diversity method for distributed WiMedia MAC for Ship Area WiMedia Network}

The present invention relates to a distributed reservation protocol (DRP) resource reservation method of a distributed WiMedia MAC (Media Access Control), which is essential for configuring an in-ship WiMedia network, and more specifically, three hops in a WiMedia D-MAC (D-MAC). The present invention relates to a method for avoiding reservation collision between devices having a distance interval and enabling relay transmission.

In the current WiMedia D-MAC standard technology, there is no DRP reservation conflict between devices with a two-hop distance. However, Distributed Reservation Protocol (DRP) reservation conflicts between devices with three hop distance intervals are not considered.

1A and 1B are diagrams illustrating a DRP reservation collision phenomenon between three hop range devices due to device mobility, and FIG. 1A is a two hop transmission without reservation collision, and FIG. 1B is a three hop range due to device mobility. This shows the situation where a DRP reservation conflict occurs.

In FIG. 1A, DEV E is a one-hop neighbor device of DEV B and DEV F, and DEV B and DEV F are neighbor devices of DEV A. In FIG. Thus, DEV E has a distance of three hops from DEV C. Thus, the DRP AC section can reserve and use the same MAS that overlaps with the DRP DE section. Since each DRP data transmission is outside the one-hop transmission range, four devices, DEV A, C, D, and E, transmit and receive data frames without interfering with each other.

However, as shown in FIG. 1B, when DEV E moves to the range of 1 hop of DEV A, the DRP DE section and the DRP AC section may experience a DRP reservation conflict.

FIG. 2 is a diagram illustrating a situation where a DRP reservation collision occurs as in FIG. 1B.

If a DRP collision in the 3-hop range occurs, only one DRP reservation segment of all conflicting DRP reservation segments maintains the reserved DRP segment, and the remaining DRP reservations are terminated, negotiating DRP reservation. You must start again. Thus, current WiMedia D-MAC standard technology can waste channel timeslots due to frequent DRP reservation collisions in the three-hop range in mobile device environments, and can consume additional transmit and receive power during DRP reservation renegotiation. This deteriorates the QoS performance in DRP transmission.

As a result, the current WiMedia D-MAC standard technology does not define a method for broadcasting three-hop hidden DRP reservation information to prevent such three-hop range collision. In FIG. 1B, since the beacon slot collision does not occur when DEV E moves to the 1 hop range of DEV A, the 3RP range DRP reservation collision problem is a problem to be solved.

SUMMARY OF THE INVENTION The present invention has been devised in the technical background as described above, and in order to avoid Distributed Reservation Protocol (DRP) reservation conflicts, it provides the potential conflict target device with an additional opportunity to maintain reserved resources, and not only a Direct Link but also a relay device. The task is to provide a DRP resource reservation method applying a cooperative relay communication technology that can reserve another link via the network.

According to the present invention, it gives the potential conflicting device an additional opportunity to maintain the reserved resources, and can reserve another link via the relay devices (MAS AC and MAS BC) as well as the Direct Link (MAS AB). To be.

In the DRP resource reservation method of a distributed WiMedia MAC according to an aspect of the present invention, a relay node has an extra power required for relay transmission, and is set to a reservation code of a relay request ('Relay Req'). When receiving a DRP IE from a reservation subject node, checking whether data can be transmitted and received in a medium access slot (MAS) SR section included in a distributed reservation protocol (DRP) information element (IE) of a reservation subject node; If it is possible to send and receive data in the section in SR, check the DRP IE for the reservation target node set to the reservation code of the relay notification ('Relay Ntf') to determine whether data transmission and reception through the corresponding MAS RT is possible. And if the relay node is available with both MAS SR and MAS RT, store the MAS RT information for relay transmission and reserve relay 'Relay Accepted' details. Transmitting the DRP IE is set to code (Reason Code) subject to reserve nodes.

In the DRP resource reservation method of the distributed WiMedia MAC according to another aspect of the present invention, the reserved node receives a DRP IE including a reservation code of a relay notification ('Relay Ntf') from the relay node. If the DRP IE for the MAS ST with the same stream index is not received from the reservation subject node, it is determined whether the MAS RT resource is allowed, and if it is available, 'Relay Accepted' Reservation Code Broadcasting the DRP IE set to the reservation subject node and the relay node, and if the reservation code (Reason Code) of the DRP IE transmitted from the relay node is 'Relay Accepted' through MAS RT Preparing to receive the data packet, otherwise deleting the information on the MAS RT.

According to the present invention, a three-hop range of DRP (Distributed Reservation) is provided by providing a potential collision target device with an additional opportunity to maintain a reserved resource and by allowing another link to be reserved via a relay device as well as a direct link. Protocol) reservation collision can be avoided, thereby improving the yield of the WiMedia D-MAC device.

1A and 1B are diagrams illustrating a DRP reservation collision phenomenon between three hop range devices due to device mobility, and FIG. 1A is a two hop transmission without reservation collision, and FIG. 1B is a three hop range due to device mobility. This shows the situation where a DRP reservation conflict occurs.
FIG. 2 is a diagram illustrating a situation where a DRP reservation collision occurs as in FIG. 1B.
3 illustrates an example of DRP relay diversity for collision avoidance, and FIGS. 4, 5, and 6 are flowcharts illustrating operations for relay transmission according to an embodiment of the present invention, respectively. , The operation of the relay node (R node) and the reservation target node (T node).
7 shows a yield value according to each mIn probability value of the D-MAC reference device.
8 shows the number of MASs reserved by one-hop neighbor devices, the one-hop range DRP collision probability according to the R1-hop value.
9 shows the collision avoidance yield value of the WiMedia D-MAC device according to the UWB / PHY data rate at each mIn probability value.

Advantages and features of the present invention, and methods of achieving the same will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are to make the disclosure of the present invention complete, and those skilled in the art to which the present invention pertains. As the invention is provided to fully inform the scope of the invention, the invention is defined only by the description of the claims. Meanwhile, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the reservation diversification method for DRP (Distributed Reservation Protocol) collision prevention according to an embodiment of the present invention, three reservation detail status codes (Reason Code) as shown in Table 1 are added for relay transmission. Accordingly, the reservation diversification method according to the embodiment of the present invention guarantees full compatibility with the WiMedia D-MAC standard and basically conforms to the DRP standard technology.

value code meaning 5 Relay req Request relay transmission to relay node 6 Relay ntf Notify reservation target node of relay transmission through relay node 7 Relay accepted DRP Resource Reservation Request Approved for This Relay Transfer

RELAY REQ A reservation code is transmitted between two nodes for a reservation owner to request a DRP reservation from a relay node. The 'Relay Req' Reason Code indirectly informs the reservation target node that there is a DRP reservation request between the reservation subject node and the relay node.

'Relay Ntf' The Reservation Code indicates that if the requested resource is approved by the relay node through the 'Relay Req' Reservation Code, Used to notify the reservation target node that data will be relayed to the reservation target node through the relay node.

Relay device which received 'Relay Req' reservation code and reservation target device which received 'Relay Ntf' reservation code is approved In case of transmission, 'Relay Accepted' Reserved Code is transmitted, and the requested relay is transmitted only when both nodes transmit 'Relay Accepted' Reserved Code. This can be done.

3 illustrates an example of DRP relay diversity for collision avoidance, and FIGS. 4, 5, and 6 are flowcharts illustrating an operation for such relay transmission, respectively, a reservation subject node (S node) and a relay node (R node). ) Shows the operation of the reservation target node (T node).

First, the operation of the reservation subject node (S node) will be described with reference to FIG. 4.

The reservation subject node first receives DRP Availability Information Elements (IEs) from neighbor devices at a distance of 1 hop as shown in FIG. 3, and then MAS for communication between the reservation subject node and the reservation target node. The MAS ST confirms that the reservation is possible (S412). The reservation subject node also receives DRP Availability IEs contained in the beacons of the relay node and the reservation target node, so that the MAS for communication between the reservation node and the relay node, that is, the MAS SR and the MAS for communication between the relay node and the reservation target node. That is, it is checked whether MAS RT can be reserved (S414).

At this time, if both the MAS S-R and the MAS R-T can be reserved for an arbitrary relay node (YES in S414), multiple reservations for DRP relay diversity are performed. First, the reservation detail status code (Reason Code) of the DRP IE is set to 'Accepted' and transmitted to the reservation target receiving node for the MAS S-T (S416).

In addition, for relay transmission, DRP IE's reservation code (Reason Code) for MAS SR is set to relay request ('Relay Req') to relay node, and relay node sends MAS RT to reservation target node. The reservation detail status code (Reason Code) of the DRP IE is set as a relay notification ('Relay Ntf') and transmitted (S416). At this time, the stream indexes of the two DRP IEs are set identically.

If there is no MAS S-T that can be reserved (No in S412), only DRP IE setting and transmission for MAS S-R and MAS R-T for relay transmission are executed (S424).

If the reservation detail status code of the DRP IE received from the reservation target node is 'Accepted' (S418), the reservation subject node which is the transmitting node directly transmits data to the reservation target node without passing through the relay node ( S420).

On the other hand, if the reservation detail status codes of the DRP IE received from the relay node and the reservation target node are all relay approved ('Relay Accepted') (S426), relay transmission is performed through the corresponding relay node (S428). If any value other than the reservation detail status code value described above is received, it operates according to the contents of the existing DRP standard.

Next, the operation of the relay node R node will be described with reference to FIG. 5.

As shown in FIG. 5, when the relay node receives the DRP IE from the reservation subject node (S510), and the reservation code (Reason Code) of the DRP IE is a relay request ('Relay Req') (S512), the relay diver It is checked whether the relay node supporting the city has extra power required for relay transmission (S514).

If the above conditions are not satisfied, the DRP IE set to the 'Denied' reservation detail status code (Reason Code) is transmitted to the reservation subject node (S516).

If the above condition is satisfied, it is checked whether data transmission / reception is possible in the MAS S-R section included in the DRP IE of the reservation subject node (S518). If reception is possible in the MAS SR, the DRP IE for the reservation target node set as the reservation detail status code (Reason Code) of the relay notification ('Relay Ntf') is checked (S522), and data transmission and reception through the corresponding MAS RT is performed. It is determined whether it is possible (S524).

If the corresponding relay node is available for both MAS SR and MAS RT (YES in S524), the MAS RT information for relay transmission is stored (S526), and the relay 'Relay Accepted' reservation detail status code (Reason Code). In step S528, the DRP IE is set to the reserved subject node.

If data transmission and reception is not possible in the MAS R-T section (No in S524), the DRP IE set to 'Conflict' reservation code (Reason Code) is transmitted to the reservation subject node (S520).

If the reservation code of the DRP IE transmitted by the reservation target node to the reservation node is 'Relay Accepted' (S530), relay transmission is performed using the stored MAS RT information (S532). If not, delete the reservation information for the MAS SR and MAS RT (S534).

The operation of the reservation target node (T node) will now be described with reference to FIG. 6.

As shown in FIG. 6, as a result of receiving the DRP IE from the relay node (S610), the DRP IE including the reservation detail status code (Reason Code) of the relay notification ('Relay Ntf') was received (“Yes” in S612). ), When the DRP IE for the MAS ST including the same stream index is not received from the reservation subject node (“No” in S 614), and the reservation target node determines whether to allow the MAS RT resource (S632). (“YES” in S632) Relay Accepted ('Relay Accepted') DRP IE set to Reserve Code (Reason Code) is broadcasted to the reservation subject node and the relay node (S622) to reserve MAS RT for relay transmission. (S624). If the reservation code (Reason Accepted) of the DRP IE transmitted from the relay node is 'Relay Accepted' (YES in S626), prepare to receive a data packet through the MAS RT (S628). If not (No in S626), the information on the MAS RT is deleted (S630).

On the other hand, when the DRP IE for the MAS ST including the same stream index is also received from the reservation subject node (YES in S614), it is first determined whether to allow the MAS ST resource (S616), and when it is reserved (S616). "Yes"), and broadcasts the DRP IE set to the 'Accepted' Reason Code to the reservation subject node and the relay node (S618).

If the reservation is not possible for the MAS S-T resource (“No” in S616), the above reservation procedure for the MAS R-T resource is executed (S620). On the other hand, when the reservation for both the MAS ST resource and the MAS RT resource is impossible, the reserved node broadcasts the DRP IE set to the reason code of 'Conflict' or 'Denied' to the reserved entity node and the relay node (S634). .

In FIG. 5 and FIG. 6, since the relay node or the reservation target node that receives the DRP IE of the reservation subject node does not support relay DRP, the reservation detail status code proposed in [Table 1] is proposed. If the code is not interpreted, the resource reservation request through the corresponding DRP IE is ignored, and thus the reservation diversity method for preventing the DRP collision according to the embodiment of the present invention is guaranteed with backward compatibility.

Performance evaluation results in the present invention was derived through the ns-2 simulation. Table 2 below shows the DRP simulation parameters used in the present invention.

variable value Total devices 30 Total simulation time 10 minutes R1-hop 30MASs / 30secs / minute N2-hop 20 DRPown 30MASs / 30secs / minute mOut 0.2 / minute

The network size, which is configured within two hops of the reference device, is 10 square meters and up to 30 devices are randomly located. In this simulation, the number of MASs included in DRP reservation intervals owned by the reference device itself is DRPown, and the number of MASs in DRP intervals reserved by neighboring devices having one hop distance from the reference device is R1-hop. And the number of MASs in the DRP sections reserved by neighboring devices two hops away from the reference device is N2-hop, while each device has two kinds of mobility such as mIn and mOut. mIn is the probability that any device moves one hop closer to the reference device, and mOut is the probability of moving one hop further away from the reference device.

To analyze the efficiency of the present invention, the concept of Theoretical Maximum Throughput (TMT) is introduced. Then, set six assumptions: (1) Bit error rate (BER) is zero. (2) There is no loss due to the collision. (3) Packet loss due to buffer overflow at the receiving node does not occur. (4) The transmitting node has enough packets to transmit. (5) The MAC layer does not use fragmentation. (6) Beacons and association frames are not considered. WiMedia standard PHY / MAC parameters and PSDU data rate based modulation parameters are applied.

7 shows a yield value according to each mIn probability value of the D-MAC reference device. In FIG. 7, by the devices in the beacon group, the transmitted frame size was fixed at 4095 bytes, and the data rate of the reference device was fixed at 480 Mbps. As shown in FIG. 7, the yield of the D-MAC device is not significantly affected by the R1-hop value, especially at an mIn probability value of more than 70%, but may vary according to the mIn value.

8 shows the number of MASs reserved by one-hop neighbor devices, the one-hop range DRP collision probability according to the R1-hop value. As shown in FIG. 8, the DRP reservation collision probability increases rapidly in proportion to the R1-hop value and the mIn value. This results in poor QoS performance and energy efficiency for WiMedia D-MAC devices. Therefore, such DRP reservation conflict must be seriously considered in designing WiMedia D-MAC technology.

9 shows the collision avoidance yield value of the WiMedia D-MAC device according to the UWB / PHY data rate at each mIn probability value. In FIG. 9, it can be seen that the yield decreases gradually as the mIn probability value of devices located two hops away increases. This is because an increase in the mIn probability causes more DRP reservation collisions. That is, this result may be a result indicating how the reservation diversification method for DRP collision prevention based on relay communication according to an embodiment of the present invention improves the yield of the WiMedia D-MAC device through collision avoidance.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the claims and their equivalents should be construed as being included in the scope of the present invention.

Claims

As a DRP resource reservation method of distributed WiMedia MAC,
If the relay node has the extra power required for relay transmission and receives the DRP IE from the reservation subject node set to the reservation code of the relay request ('Relay Req'), the DRP IE of the reservation subject node. Checking whether data transmission and reception are possible in the MAS SR section included in the;
If data transmission / reception is possible in the MAS SR, checks the DRP IE for the reservation target node set as the reservation code of the relay notification ('Relay Ntf') and checks whether data transmission and reception through the corresponding MAS RT is possible. Judging the;
If the relay node is available for both MAS SR and MAS RT, the DRP IE stores MAS RT information for relay transmission and sets the relay acceptance (Relay Accepted) Reservation Code to the reservation subject node. DRP resource reservation method comprising the step of.

As a DRP resource reservation method of distributed WiMedia MAC,
The reservation target node received the DRP IE including the reservation code of the relay notification ('Relay Ntf') from the relay node but did not receive the DRP IE for the MAS ST with the same stream index from the reservation subject node. If not, determine whether to accept the MAS RT resource and, if available, broadcast a DRP IE set to a 'Relay Accepted' Reservation Code to the reservation subject node and the relay node;
If the reservation code (Reason Accepted) of the DRP IE transmitted from the relay node is 'Relay Accepted', prepare to receive the data packet through the MAS RT, otherwise the information about the MAS RT DRP resource reservation method comprising the step of deleting.