KR101394217B1 - Medium access control method of enhanced ad-hoc self-organizing time division multiple access type for base station - Google Patents

Abstract

The present invention relates to a medium access control method with an enhanced ad-hoc self-organizing time division multiple access method for a base station, more particularly, to a medium access control method with an enhanced ad-hoc self-organizing time division multiple access method designed with an enhanced ad-hoc self-organizing time division multiple access (EASO-TDMA) communication method which is to improve the disadvantage of a communication method due to an ad-hoc self-organizing time division multiple access (ASO-TDMA) which is previously used and is to more practically correspond to environment change of marine communication.

Description

TECHNICAL FIELD [0001] The present invention relates to a Medium Access Control Method for Enhanced Ad-hoc Self-Organizing Time Division Multiple Access

The present invention relates to a time division multiple access method medium access control method for a land station, and more particularly, to a communication method using an ad hoc self-organizing time division multiple access (ASO-TDMA) And more particularly, to an enhanced ad hoc autonomous time division multiple access (MAC) access method for a land station, which is capable of more effectively responding to changes in the environment of maritime communication and providing usefulness to land stations.

Generally, a base station is a base station installed on the land. It is a station that communicates with marine vessels to support the safe navigation and logistics activities of the ship.

In addition, in order to perform multi-hop data communication through the VHF band with the ship station installed in the marine vessel located on the sea, the above-mentioned land station has an ad hoc autonomous configuration (MAC) as a Medium Access Control (ASMA-TDMA) scheme is used in the TDMA scheme.

In other words, the land station communicates with the ship station of the marine vessel through the ASO-TDMA scheme.

However, the ASO-TDMA method, which has been used as a MAC for maritime communication, has difficulty in stable data transmission between a land station and a ship station.

In addition, although there are many changes in the environmental conditions such as the increase of the communication data rate and the change of the maritime communication environment of the VHF band compared to the existing ones, they are not reflected substantially.

In addition, since the time slot is fixed in the land station using the existing ASO-TDMA scheme, the time slot is allocated only to the corresponding sub-time frame, so that the time delay during the multi-hop communication increases and timeout occurs frequently And there was no factor controlling network congestion.

On the other hand, the patent documents of the prior art document disclose that a maritime vessel receives marine digital data through a multi-band communication device capable of performing communication in a plurality of bands, A multi-band communication system for marine digital data exchange capable of wirelessly transmitting information data by selecting a communication device, an ad hoc communication method in a microwave band using the same, a multi-band communication method, and a marine network And the like.

[Patent Literature] Korean Published Patent Application No. 10-2011-0033553 (published on March 31, 2011)

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a communication method using an Ad Hoc Self-Organizing Time Division Multiple Access (TDMA) Enhanced EAS-TDMA (TDMA) communication scheme, which is designed to improve the performance of the mobile communication system and to provide a more realistic response to changes in the environment of maritime communication. There is provided a method of controlling access to a land station in an ad hoc autonomous time division multiple access system.

The present invention relates to an enhanced ad hoc autonomous time division multiple access (SHA) type land mobile communication system capable of avoiding a reception collision while reducing overall transmission delay due to maritime communication with a ship station, There is another purpose in providing a connection control method.

The problem to be solved by the present invention is not limited to the above-mentioned problem (s), and another problem (s) not mentioned can be clearly understood by a person skilled in the art from the following description.

In order to solve the above problems, an enhanced ad hoc autonomous time division multiple access (MAC) access method for a land station according to a preferred embodiment of the present invention includes a MAC (Medium Access Control) frame structure, A method for controlling a medium access control method for a terrestrial station in a time division multiple access system,

(A) synchronizing a time frame of the MAC frame; (B) checking whether a time slot number (NO _TS ) is equal to a reserved time slot number (NO _TSrsv ) in a process for allocating a time slot in the time frame; (C) the (B) time slot number in step (NO _TS) is reserved a time slot number (NO _TSrsv) and equal, the sub-time frame number in each time frame (NO _SF) = 10 and time-slot number (NO _TS ) = 220; (D) If the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 220 in step (C), the switch from the reception mode RX to the transmission mode TX, Transmitting a beacon and a packet to the beacon; (E) incrementing the time slot number (NO _TS ) by one; (F) after the step (E), confirming whether the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215; (G) checking whether the time slot number (NO _TS ) is greater than 225 if the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215 in step (F); (H) comprising in the (G) step time slot number (NO _TS) is large, a time slot number (NO _TS) = 1 by increasing one of the sub-time frame number (NO _SF) than the 225: (I) After step (H), it is determined whether the sub-time frame number (NO _SF ) is greater than 10; (J) confirming whether to end the program if the sub-time frame number (NO _SF ) is greater than 10 in the step (I); (K) If it is determined in step (J) that the program is to be terminated, the program is terminated; otherwise, the time slot number (NO _TS ) is set to 1 and the sub time frame number (NO _SF ) A step of regressing the program progress to a step of; As a basic feature of the technical construction.

The details of other embodiments are included in the detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and / or features of the present invention and the manner of achieving them will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. And is provided to fully explain the scope of the present invention to those skilled in the art.

According to the present invention, it is possible to improve the disadvantages of the conventional communication method using Ad-hoc Self-Organizing Time Division Multiple Access (TDMA) (EASO-TDMA) communication method capable of performing an enhanced ad-hoc configuration TDMA (Time Division Multiple Access (TDMA)

The present invention can reduce the overall transmission delay due to maritime communication with the ship station, avoid the reception collision, and can also control the network congestion.

Brief Description of the Drawings Fig. 1 shows a MAC frame structure for illustrating an understanding of the present invention. Fig.
FIG. 2 is a diagram showing a header definition for the MAC frame of FIG. 1 in the present invention. FIG.
Figure 3 is a chart depicting the definitions of the parameters described in the present invention.
FIG. 4 is a flow chart illustrating a method of processing a medium access control method for a land-office of an enhanced ad hoc autonomous configuration time division multiple access scheme according to a preferred embodiment of the present invention.
5 is a diagram illustrating a time frame and a sub time frame in the present invention;
6 is a detailed flowchart showing RPP_BS processing in the present invention.
7 shows an example of a type of neighboring ship station table in the present invention.
8 is a diagram for explaining a queuing processing method of a received packet in the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The enhanced ad hoc autonomous structured time division multiple access system access control method for a land station according to a preferred embodiment of the present invention is performed based on a medium access control (MAC) frame structure shown in FIG. 1, FIG. 2 shows a table defining a MAC frame header to help understand the headers of the MAC frame structure.

In addition, FIG. 3 shows a table defining network parameters for easy understanding of various network parameters used in the description of the present invention.

As shown in FIG. 4, the enhanced ad hoc autonomous structured time division multiple access (MAC) access method for a land station according to a preferred embodiment of the present invention synchronizes a time frame with the start of a MAC frame (S1).

As shown in FIG. 5, the time frame has a plurality of sub-time frames for one time frame, and can be set to 10 sub-time frames per one time frame. One time frame corresponds to 10 sub- Time frame, it can be defined that each sub-time frame constitutes 225 time slots equally.

Next, it is checked whether the time slot number (NO _TS ) is equal to the reserved time slot number (NO _TSrsv ) in the process of allocating the time slot in the time frame (S2).

If the time slot number (NO _TS ) is equal to the reserved time slot number (NO _TSrsv ) in step S2, it is determined whether the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 220 in each time frame (S3).

If the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 220 in step S3, the mobile station switches from the reception mode RX to the transmission mode TX and transmits a beacon with a reserved time slot. And a packet (S4).

After step S4, it is checked whether the sub-time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215 after increasing the time slot number (NO _TS ) by one (S5) .

If it is determined in step S6 that the sub-time frame number (NO _SF ) is 10 and the time slot number (NO _TS ) is not 215, it is checked whether the time slot number (NO _TS ) is greater than 225 (S7).

In step S7, if the time slot number (NO _TS ) is greater than 225, the time slot number (NO _TS ) is set to 1 and the sub time frame number (NO _SF ) is incremented by one (S8).

At this time, if the time slot number (NO _TS ) is not greater than 225 in step S7, the program proceeds to step S2.

After step S8, it is checked whether the sub-time frame number (NO _SF ) is greater than 10 (S9).

If the sub-time frame number (NO _SF ) is greater than 10 in step S9, it is checked whether the program is to be terminated (S10).

At this time, if it is confirmed that the program is terminated, the program is terminated.

If the program is not terminated in step S10, a time slot number (NO _TS ) is set to 1, a sub time frame number (NO _SF ) is set to 1, and program progression is regressed in step S2 (S11).

If it is determined in step S2 that the time slot number (NO _TS ) is not equal to the reserved time slot number (NO _TSrsv ), one of the two processes can be selectively performed.

At this time, one of the two processes switches to the reception mode (RX) to receive a packet from the ship stations if the time slot number (NO _TS ) is not equal to the reserved time slot number (NO _TSrsv ) And performs an RPP_BS (Received Packet Processing Base Station) for sorting and processing according to the type of packet (S21).

At this time, after performing the step S21, the program moves to the step S5.

Here, in the land station, since the ship stations are allocated the time slots, they are switched to the receive mode, and RPP_BS is performed to receive packets from the ship stations.

The other one of the two processes are not the same as in the S2 stage time slot number (NO _TS) is a time slot number (NO _TSrsv) reservation, a time slot number (NO _TS), a new sub-time frame number (NO _SF) (S22).

Here, the new sub-time frame number (NO _SF) is to determine a time slot number (NO _TS) to going to increase a time slot number (NO _TS) that is above 225 the sub-time frame number (NO _SF) 1 each Time frame number (NO _SF ) = 10 to change the time frame number and to keep track of this parameter in the land station so as to usefully check the increase of the sub time frame number (NO _SF ).

If it is determined in step S22 that the time slot number (NO _TS ) is the new sub time frame number (NO _SF ), it is checked whether the packet storage queue Q _{TX_PL} storing the packet to be transmitted to the physical layer is empty (step S23) .

If the packet storage queues (Q _{TX _ PL)} for storing the packets to be transmitted to the physical layer in the step S23 is not empty, and transmits the packet to be sent in the next time frame to the physical layer (S24).

If the packet storage queue Q _{TX_PL} for storing a packet to be transmitted to the physical layer is empty in step S23, the program moves to step S5.

If it is determined in step S22 that the time slot number (NO _TS ) is not the new sub time frame number (NO _SF ), it is checked whether the time slot number (NO _TS ) is smaller than the reserved time slot number (NO _TSrsv ) ).

If the time slot number (NO _TS ) is smaller than the reserved time slot number (NO _TSrsv ) in step S25, the program proceeds to step S23. Otherwise, the program moves to step S5.

If it is determined in step S3 that the sub-time frame number (NO _SF ) is equal to 10 and the time slot number (NO _TS ) is not equal to 220, the mobile station switches from the reception mode RX to the transmission mode TX, After the transmission (S31), the program moves to the step S5.

In addition, the correct, in step S6 the sub-time frame number (NO _SF) = 10 and time-slot number (NO _TS) = 215, to make the time-out is generated whether or not the packet sent to the ship station (S41).

If a timeout of a packet sent to the ship station has occurred in step S41, it is checked whether N _B (the number of time slots occupied by the land station) and N _Bmax (the maximum number of time slots occupied by the land station) are equal S42).

In this case, N is equal to _B (land station the number of the occupied time slot) and N _Bmax (maximum number of time slots occupied by the land station) in the step S42, the return process the program in the step S2.

The in S42 step N _B (land station the number of the occupied time slot) and N _Bmax (land station a maximum number of time slots that occupies) is not the same, N _B (land station the number of the occupied time slot) value (S43), the program is returned to the step S2.

Here, it is desirable to increase the number of time slots when N _B (the number of time slots occupied by the land station) value is less than N _Bmax (the maximum number of time slots occupied by the land station) value.

If the timeout packets are sent to the ship station in the S41 step did not occur, check the equality N _B (land stations the number of occupied time slots) and N _Bmin (land stations is the minimum number of time slots are occupied) (S44).

If N _B (the number of time slots occupied by the land station) and N _{B min} (the number of the minimum time slots occupied by the land station) are equal to each other in step S44, the program is regressed to step S2.

If the N _B (land station the number of the occupied time slot) and N _Bmin (land station the minimum number of time slots that occupies) in the S44 step like, N _B (land station the number of the occupied time slot) value (S45), the program is returned to the step S2.

Here, N _B (land station the number of the occupied time slot) when the value _Bmin N (land station the minimum number of time slots that occupies) larger than the value, it is preferable to decrease the number of time slots.

FIG. 6 shows time slots per sub-time frame occupied by time slot allocation according to the present invention.

Further, in the present invention having the above-described steps, the land station has a time slot allocation scheme in which a fixed time slot is allocated by N _B (the number of time slots occupied by the land station), which is sent to the ship station a time-out if the packets according to the update time for each frame, such as increasing or decreasing the number of time slots N _B (land station the number of the occupied time slot) value and transmits a beacon.

Such beacon transmission can prevent collision between time slots by informing the ship stations at a distance of one-hop communication with the land station by N _B (the number of time slots occupied by the land station) Ship stations at the received one-hop communication distance release the corresponding time slot or allocate the corresponding time slots and transmit the packet.

Here, if the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 225, then all ship stations receive the DTS (Determine Time Slot) to set the time slot in the sub time frame (Idle) state.

Meanwhile, the RPP_BS (Received Packet Processing Base Station) performed in step S21 receives the packet from the ship stations in the one-hop communication distance, And checks whether an error has occurred in the packet received from the ship stations (S21-1).

At this time, if an error occurs in step S21-1, the received packet is dropped (S21-2), and the program is terminated.

If no error has occurred in step S21-1, the neighboring ship station table (NS table) is updated (S21-3).

The neighboring ship station table can be configured as one type as shown in FIG. 8, and can extract and update and store the parameter information shown in the table of the table in the packet received from the ship stations, Can be an indicator of the idle time slot.

After updating the neighboring ship station table through step S21-2, it is confirmed whether the packet received from ship stations is a data packet (D_packet) (S21-4).

The data packet is correct in the step S21-4, IP-based or non-IP-based in accordance with the received from (the IP-based data packet storage queue received from the physical layer) or Q _{RX _ _NIP PL} (physical layer Q _{RX_PL_IP} non-IP-based data Packet storage queue) (S21-5).

After step S21-5, it is confirmed whether the data packet is uplinked (S21-6).

At this time, if the uplink processing is performed in step S21-6, it is checked whether the fragment number (LEN) of the MAC frame is "1" (S21-7).

If it is determined in step S21-6 that the uplink processing has not been performed, the process proceeds to step S21-2 where drop processing is performed.

If in the step S21-7 MAC (MAC) pieces of the frame number (LEN) is "1", and transmits it to remove the header of the MAC address Q _{TX _ NL} (packet storage queues to be sent to the network layer) (S21- 8).

If it is determined in step S21-7 that the fragment number (LEN) of the MAC frame is not "1", it is checked whether the fragment number FN of the MAC frame is equal to the fragment number LEN of the MAC frame S21-9).

Equal to the fragment number (FN) and the MAC (MAC) pieces of the frame number (LEN) of the MAC frame in the step S21-9, the program proceeds to the above step S21-8 remove the header of the MAC address Q _{TX_NL} (Network To the packet storage queue to be transmitted to the layer).

In addition, if the piece number (FN) and the MAC (MAC) pieces of the frame number (LEN) of the MAC frame in the same step S21-9, sends the data packets to a _TX Q _{_ DL} (data packet temporary storage queue) ( S21-10).

If it is determined in step S21-4 that the packet is not a data packet, it is checked whether the packet received from the ship stations is a routing packet (S21-11).

If the packet received from the ship stations in step S21-11 is correct, the route setting packet is stored in _{QRX_PL_R} (queue storing the route setting packet received from the physical layer) (S21-12) The program proceeds to step S21-8 and removes the header of the MAC address and transmits it to Q _{TX_NL} (packet storage queue to be transmitted to the network layer).

If the packet received from the ship stations in step S21-11 is not a routing packet, NO _SF (sub-time frame number) and NO _TS (time slot number) are checked and the neighboring ship station table is updated (S21- 13).

At this time, but the receiving and the release notes check _SF NO and NO _TS value the step S21-13, it is possible to remove the NO and NO _{TS SF} value and performing the update processing for the idle time slot.

Meanwhile, in the present invention, it is preferable to perform a queuing process on received packets in the RPP_BS (Received Packet Processing Base Station) performed in step S21. As shown in FIG. 9, One packet is transmitted to the physical layer for queuing, and the packet received from the physical layer is transmitted to the network layer or the physical layer again for queuing processing.

At this time, in the received packet, the data packet is not transmitted but is transmitted by its own data. The data packet can be classified into an IP-based packet and a non-IP-based packet, and a route setting packet is generated for a communication path setting of the ship stations or its own communication path .

In this case, the packets received from the network layer are transmitted to the physical layer for queuing (PQ1). The queuing priority is determined based on a route setting packet (R_packet)> an IP based data packet (D_packet) (D_packet).

In addition, the packet received from the physical layer is transmitted to the network layer or the physical layer again to perform the queuing process (PQ2). The queuing priority is the IP based data packet (D_packet)> the routing packet> the non-IP based data packet (D_packet) . ≪ / RTI >

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It will be understood by those skilled in the art that various changes, modifications, substitutions, and equivalents may be made therein without departing from the spirit and scope of the invention.

Claims (8)

An access control method for an ad hoc autonomous configuration time division multiple access method for a land station, which is performed based on a medium access control (MAC) frame structure,
(A) synchronizing a time frame of the MAC frame;
(B) checking whether a time slot number (NO _TS ) is equal to a reserved time slot number (NO _TSrsv ) in a process for allocating a time slot in the time frame;
(C) the (B) time slot number in step (NO _TS) is reserved a time slot number (NO _TSrsv) and equal, the sub-time frame number in each time frame (NO _SF) = 10 and time-slot number (NO _TS ) = 220;
(D) If the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 220 in step (C), the switch from the reception mode RX to the transmission mode TX, Transmitting a beacon and a packet to the beacon;
(E) incrementing the time slot number (NO _TS ) by one;
(F) after the step (E), confirming whether the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215;
(G) checking whether the time slot number (NO _TS ) is greater than 225 if the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215 in step (F);
(H) in the step of (G) step time slot number _(TS NO) is large, a time slot number (NO _TS) = 1 to increase and one sub-time frame number (NO _SF) than 225:
(I) after step (H), confirming whether a sub time frame number (NO _SF ) is greater than 10;
(J) confirming whether to end the program if the sub-time frame number (NO _SF ) is greater than 10 in the step (I);
(K) If it is confirmed that the program is terminated in the step (J), the process ends; otherwise, the time slot number (NO _TS ) is set to 1 and the sub time frame number (NO _SF ) Regenerating the program progression; Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 1,
(B-1) In step (B), if the time slot number (NO _TS ) is not equal to the reserved time slot number (NO _TSrsv ), the base station switches to the reception mode (RX) Performing a received packet processing base station (RPP_BS) for classifying and processing according to the type, and then proceeding to the step (E); Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 1,
(Ba) determine whether the (B) If in the step of time equal to the slot number (NO _TS) is a time slot number (NO _TSrsv) reservation, a time slot number (NO _TS), a new sub-time frame number (NO _SF) ;
(Bb) If the time slot number (NO _TS ) in the (Ba) step is confirmed as a new sub time frame number (NO _SF ), it is checked whether the packet storage queue Q _{TX - - PL} for storing a packet to be transmitted to the physical layer is empty Checking;
(Bc) If the packet storage queue (Q _{TX - PL} ) storing a packet to be transmitted to the physical layer in step (Bb) is empty, the program is advanced to step (E), and a packet for storing a packet to be transmitted to the physical layer Transmitting a packet to be sent in the next time frame to the physical layer if the queue (Q _{TX - - PL} ) is not empty;
(Bd) If the time slot number (NO _TS ) in the step (Ba) is not the new sub time frame number (NO _SF ), it is checked whether the time slot number (NO _TS ) is smaller than the reserved time slot number (NO _TSrsv ) ;
(Be) If the time slot number (NO _TS ) is smaller than the reserved time slot number (NO _TSrsv ) in the step (Bd), the program is advanced to the step (Bb). If not, Progressing; Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 1,
(C-1) If the sub-time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 220 in step (C), the mobile station switches from the reception mode RX to the transmission mode TX, Transmitting a packet with a time slot, and then proceeding to the step (E); Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 1,
(F-1) checking whether a timeout of a packet sent to the ship station occurs if the sub time frame number (NO _SF ) = 10 and the time slot number (NO _TS ) = 215 in step (F);
(F-2) If a timeout of a packet sent to the ship station in the step (F-1) has occurred, N _B (the number of time slots occupied by the land station) and N _Bmax (the maximum time slot occupied by the land station) The number of < / RTI >
(F-3) above (F-2) Step N _B (land station the number of the occupied time slot) at the N _Bmax (land station a maximum number of time slots that occupies) is equal to the (B) step the program Otherwise, adding 80 to the value of N _B (the number of time slots occupied by the land station) and proceeding to the step (B);
(F-4) If there is no timeout of the packet sent to the ship station in the (F-1) step, N _B (the number of time slots occupied by the land station) and N _Bmin Number of time slots) is the same;
(F-5) wherein (F-4) N _B (land station the number of the occupied time slot), in step with N _Bmin (land station the minimum number of time slots that occupies) is equal to the (B) step the program Decreasing the value of N _B (the number of time slots occupied by the land station) to 80, and then advancing the program to the step (B); Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
3. The method of claim 2,
The RPP_BS in the step (B-1)
(B-1a) confirming whether an error has occurred in a packet received from ship stations;
(B-1b) if an error occurs in the step (B-1a), dropping the received packet and terminating the program;
(B-1c) updating the neighboring ship station table (NS_table) if an error has not occurred in the step (B-1a);
(B-1d) After the step (B-1c), it is confirmed whether the packet received from ship stations is a data packet (D_packet).
(B-1e) If the data packet is correct in the step (B-1d), Q _{RX_PL_IP} (IP based data packet storage queue received from the physical layer) or Q _{RX_PL_NIP} A non-IP based data packet storage queue);
(B-1f) After the step (B-1e), confirming whether the data packet is uplinked;
(B-1g) checking whether the fragment number (LEN) of the MAC frame is "1" if the uplink processing is performed in the step (B-1f);
(B-1h) If the fragment number (LEN) of the MAC frame is '1' in the step (B-1g), the MAC address header is removed and Q _{TX_NL} (packet storage queue to be transmitted to the network layer) Transmitting; Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 6,
If the fragment number LEN of the MAC frame is not "1 " in the step (B-1h), the fragment number FN of the MAC frame and the fragment number LEN ) Are the same;
If the fragment number FN of the MAC frame is equal to the fragment number LEN of the MAC frame in the step (B-1), the program proceeds to the step B-1h, Removing the header of the packet and transmitting it to Q _{TX_NL} (packet storage queue to be transmitted to the network layer);
(B-1k) If the fragment number FN of the MAC frame and the fragment number LEN of the MAC frame are not equal in the step (B-1i), the data packet is transmitted as Q _{TX_DL} (data packet temporary storage queue) Transmitting;
(B-11) checking whether the packet received from the ship stations is a routing packet if it is not a data packet in the step (B-1d);
(B-1m) If the packet received from the ship stations in the step (B-11) is correct, the path setting packet is stored in Q _{RX_PL_R} (queue storing the path setting packet received from the physical layer) (B-1h), removing the header of the MAC address, and transmitting the packet to the Q _{TX_NL} (packet storage queue to be transmitted to the network layer);
(B-1) If the packet received from the ship stations in the step (B-11) is not a routing packet, it checks the NO _SF (sub time frame number) and the NO _TS (time slot number) ; Wherein the method comprises the steps of: (a) determining whether the MAC address of the access point is the MAC address of the access point;
The method according to claim 6,
In the received packet,
The packet received from the network layer is transmitted to the physical layer for queuing processing. The queuing priority is processed by a route setting packet (R_packet)> an IP based data packet (D_packet)> a non-IP based data packet (D_packet)
The packet received from the physical layer is queued by being transmitted to the network layer or the physical layer again, and the queuing priority is processed by an IP-based data packet (D_packet)> a path setting packet> a non-IP based data packet (D_packet) Wherein the method comprises the steps of: (a)

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