KR102035791B1 - Node for generating resource efficient frame structure in TDMA system - Google Patents

Abstract

Provided is a center node generating a frame structure for a resource efficiency in a TDMA system. The center node generating a frame structure for a resource efficiency in a time division multiple access (TDMA) system generates a frame containing a plurality of time slots in which the center node is allocated to all subscribing nodes one or more times per one frame among all subscribing nodes subscribed in the TDMA network. Each of the time slots forming the frame contains a dummy field containing minimum p numbers of mini slots for automatic gain control (AGC), preamble and guard time setting and a data field including dynamic mini slots which are allocated by different numbers according to data types transmitted and received by subscribing nodes and operating environments and make the length of a time slot vary, wherein the number of the dynamic mini slots is integer-multiple of data allocation basic unit. Accordingly, the present invention can support various delay time and various transmission speed.

Description

Node for generating resource efficient frame structure in TDMA system

The present invention relates to a central node for generating a frame structure for resource efficiency in a TDMA system, and more particularly, to a frame structure for resource efficiency in a TDMA system that dynamically allocates and operates timeslots on a TDMA based network. It's about the central node you create.

In a mobile communication system, a multiple access method is a method in which a plurality of subscribers share and access a limited wireless line, such as frequency division multiple access (FDMA), time division multiple access (TDMA), and code division. It is classified as Code Division Multiple Access (CDMA).

Among the multiple access schemes, the TDMA scheme refers to a scheme in which a plurality of users share one carrier by using a designated time slot within a time interval called a frame, and use a common frequency band.

LINK-16, a typical TDMA-based group communication method, performs resource allocation by changing the time slot interval for each node based on the RRN while the size of the time slot is fixed.

Military data link systems require a communication distance of more than a few hundred kilometers, which makes the TDMA scheme occupy a large portion of the time slot, taking into account the guard time due to the propagation delay caused by bidirectional communication. In other words, each time slot includes a protection time considering bidirectional propagation delay, which reduces the efficiency of communication resource operation, and requires complex resource allocation procedures to simultaneously satisfy various traffic requirements.

Korean Patent Publication No. 10-2018-0069300 (published on June 25, 2018)

The technical problem to be solved by the present invention in order to solve the above-mentioned problem is to allocate a TDMA network by changing the time slot length in accordance with the requirements of the traffic through mini slot-based dynamic timeslot allocation to meet various operating environments and user needs It is to present a central node that creates a frame structure for resource efficiency in a TDMA system that can change and operate a suitable network in real time.

The problem of the present invention is not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

As a means for solving the above technical problem, according to an embodiment of the present invention, the central node for generating a frame structure for resource efficiency in the TDMA system, the central node of all the subscription nodes subscribed to the TDMA network Create a frame comprising a plurality of timeslots allocated to the subscribing nodes one or more times per frame, each of the plurality of timeslots constituting the frame having an Automatic Gain Control (AGC), preamble and guard time setting A dummy field comprising a minimum of p minislots for a; And dynamic minislots allocated in different numbers according to data types and operational environments transmitted and received by the subscribing nodes, such that the lengths of the timeslots are dynamically changed. It includes a data field.
In this case, p is set to 3.

If the data allocation basic unit is q minislots (q> p), the q integer multiples are set differently according to the data type and operating environment, and the central node is a dynamic minislot allocated to the data field. The number of nodes is varied for each of the subscribing nodes to support independent delay time and transmission speed for each subscribing node.

The central node divides the one frame corresponding to one second into 25 auxiliary frames, and allocates one or more timeslots to each of the subscribing nodes one or more times per one auxiliary frame.

In the case of resource allocation for supporting the maximum transmission rate for each of the subscribing nodes, the center node assigns one subframe as many as the number of subscribing nodes so that a dummy field of the subscribing nodes is allocated once to a subframe. And dividing the number of minislots corresponding to the one auxiliary frame by the number of subscribing nodes to allocate the same number of dynamic minislots to the subscribing nodes.

In the case of resource allocation for the minimum delay time for each of the subscribing nodes, the central node allocates the same number of dynamic minislots to the data field for each subscribing node, wherein n is the basic unit of data allocation for the minimum delay time. Allocate mini slots.

The central node sets a time corresponding to a unidirectional propagation delay in order to minimize the decrease in resource efficiency due to the propagation delay.

The central node allocates one or more minislots between the timeslots as type slot offsets according to the communication distance between the subscribing nodes for coverage extension.

When there is at least one other central node that manages overall resource allocation among the subscribing nodes, the central node is configured such that the central node and the other one or more central nodes share one TDMA network at the same time. The entire minislots present in the frame are divided into two or more groups and assigned to the central node and one or more other central nodes, respectively.

The center node is a pattern of a preamble set in the dummy field and includes a synchronization pattern set in a preamble of a first timeslot of the frame and a preamble of the remaining timeslots of the frame to obtain synchronization of an initial frame of each subscribing node. Set one of the general patterns to be set.

The central node assigns a relay time slot to the relay node by designating a relay node for a relay role between the center node and the mission node among the subscribing nodes, and source and destination information in a header of the relay time slot. In this example, information about the center node and the mission node is described, data to be relayed to the mission node is described in a payload, and the relay node is a time slot in which data to be relayed in the payload is assigned to the mission node. To send to the mission node.

On the other hand, according to another embodiment of the present invention, the dynamic timeslot allocation apparatus for resource efficiency in a TDMA system including a plurality of subscribing nodes, according to the data type and operating environment to analyze the input resource allocation input information; A resource allocation information generation unit for dynamically varying sizes of time slots to be allocated to a plurality of subscribing nodes, and determining resource positions and generating resource allocation information, which is time slot map information, in units of superframes; A resource allocation information processor configured to generate payload data by receiving data to be transmitted using the timeslots based on the timeslot map information; And a frame generation unit configured to generate a frame by loading the generated payload data in a corresponding time slot among the time slots to be transmitted to the subscribing nodes, wherein the resource allocation information generating unit includes: Allocating one or more timeslots per frame and varying the number of minislots to be allocated to one timeslot according to the data type and operating environment, based on an integer multiple of a predetermined data allocation basic unit. Generate slot map information.

The resource allocation information generation unit may be assigned a different number according to at least p minislots for automatic gain control (AGC), preamble and guard time setting, and data types and operational environments transmitted and received by the subscribing nodes. A time slot map information is generated by generating a structure of a variable timeslot by using dynamic minislots such that the length is dynamically variable, and generating the structure of the variable timeslot in units of a superframe composed of a plurality of frames.

When the number of dynamic minislots allocated to the subscribing nodes for each timeslot corresponds to an integer multiple of a data allocation basic unit, and the resource allocation information generating unit includes q minislots q> p, The q integer multiples are set differently according to the data type and the operating environment, so that the number of dynamic minislots allocated to the data field varies for each of the subscribing nodes, so that the delay time and the transmission rate are independent for each subscribing node. Support.

According to the present invention, a frame is composed of a plurality of minislots, a certain number of minislots are defined as data allocation basic units, and a time slot is configured as an integer multiple of the data allocation basic unit for each operation mode, thereby providing various delay times and various transmissions. Can support speed.

In addition, according to the present invention, the resource efficiency can be increased by configuring the TDMA network in real time according to the operating environment of various nodes and the characteristics (voice, video, etc.) of data to be used in the TDMA network.

In addition, according to the present invention, by configuring the TDMA network through the mini-slot-based dynamic timeslot allocation to solve the problems caused by data delay or overlapping, and to support a variety of network and communication systems such as coverage extension and relay structure such as communication distance Applicable to

In addition, according to the present invention, the transmission efficiency can be increased by setting the guard time in consideration of the unidirectional delay time.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 illustrates a frame structure for resource efficiency generated by a central node in a dynamic TDMA system according to an embodiment of the present invention;
2 is a diagram illustrating a structure of a minislot based timeslot according to an embodiment of the present invention;
3 is a diagram illustrating a resource allocation structure for supporting a maximum transmission rate for each subscription node;
4 is a diagram illustrating a resource allocation structure for supporting a minimum delay time for each subscription node;
5 is a diagram illustrating a resource allocation structure including a timeslot offset;
6 is a diagram illustrating a resource allocation structure using a relay timeslot;
7 is a diagram illustrating a state transition diagram of a subscription node for TDMA network synchronization and timeslot control, and FIG.
8 is a block diagram illustrating a dynamic timeslot allocation apparatus for resource efficiency in a TDMA system according to an embodiment of the present invention.

Objects, other objects, features and advantages of the present invention will be readily understood through the following preferred embodiments associated with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

Also, 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 may also include the plural unless specifically stated otherwise in the phrase.

Hereinafter, specific technical contents to be implemented in the present invention will be described in detail with reference to the accompanying drawings.

In some cases, it is mentioned in advance that parts of the invention which are commonly known in the description of the invention and which are not highly related to the invention are not described in order to prevent confusion in explaining the invention without cause.

Each configuration of device 800 shown in FIG. 8 represents a functional and / or logical separation, and does not necessarily mean that each configuration is divided into separate physical devices or written in separate code. The average expert in the art of the present invention will be able to reason easily.

The central node or device 800 may include a program installed in a predetermined data processing device to implement the technical idea of the present invention.

In addition, the central node according to an embodiment of the present invention, for example, all electronic devices capable of installing and executing programs such as a desktop PC, a server, a laptop PC, a netbook computer, and the like. One or one of them may include an electronic device.

In addition, the dynamic timeslot allocation apparatus 800 for resource efficiency according to an embodiment of the present invention is capable of installing and executing a program such as a microprocessor, a memory, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and the like. Can be implemented using a central node.

In addition, in an embodiment of the present invention, subscription nodes of a dynamic time division multiple access (TDMA) network include a central node and a mission node. The central node may be a control center or ground node that controls mission nodes or generates resource allocation information and broadcasts them to the mission nodes. The mission node may be a loading node mounted on an aircraft such as a drone, a warship, or an amphibious weapon.

The subscribing nodes may transmit and receive various types of data according to various operation modes, such as transmitting and receiving voice data or video data, or a central node (control center) transmitting and receiving operation data for coordinating a mission node (for example, a vehicle). Can be.

In addition, the basic unit of data allocation means the minimum number of minislots (q, for example, 4) required to transmit data in the TDMA network, and is an integer multiple of the basic unit of data allocation according to the latency requirement or transmission rate. Corresponding minislots may be assigned to one timeslot.

The unit of data allocation change is a frame corresponding to 1 second and may be used as a unit for changing resource allocation information. That is, the central node may broadcast the subscribed nodes by changing the timeslot map in units of 1 second.

In addition, the reference unit of data allocation is a unit configured to manage all resources, that is, a unit for generating a timeslot map. When a time slot map is generated every 16 seconds by managing all resources in units of 16 seconds, one time The slot map includes resource allocation information for 16 seconds. Thus, for example, 16 seconds is a reference unit of data allocation, and 1 second is a unit capable of changing data allocation.

1 is a diagram illustrating a frame structure for resource efficiency generated by a central node in a dynamic TDMA system according to an embodiment of the present invention.

Referring to FIG. 1, a central node (not shown) according to an embodiment of the present invention may generate a frame 100 in which timeslots are allocated to one or more times per frame to all of the subscribing nodes subscribed to the TDMA network. have.

The frame 100 used for resource allocation in a TDMA network is composed of a plurality of mini slots, and is also composed of a plurality of variable timeslots TS1 to TSn. In the case of FIG. 1, the central node may generate one frame including n variable timeslots, and may generate one timeslot with a plurality of minislots.

The central node may allocate resources such that the same number of timeslots are allocated to subscribing nodes in one frame, but may also allocate different numbers of timeslots in some cases.

In the following description, one frame is one second, and a case of 3100 mini slots will be described as an example. In addition, the frame is used as a unit of data allocation change, and the central node may allocate time slots to subscribing nodes by combining minislots in the frame.

All subscribing nodes are assigned at least one timeslot per frame, and 16 frames are defined as superframes (i.e., 16 seconds, 49,600 minislots), so that the central node is the reference for sync slot and data allocation per subscribing node. Can be used as a unit.

In addition, for convenience and efficiency of resource allocation, the central node may allocate a time slot by dividing one frame into 25 subframes. Since one frame corresponds to one second, one auxiliary frame corresponds to 40 msec. The central node may allocate resources such that all subscribing nodes are assigned one or more timeslots per one auxiliary frame as shown in FIG. 3. Twenty-five auxiliary frames are not limited thereto as an example.

In addition, the central node can use a minislot as a basic unit of frame composition and data allocation by applying a structure that varies the length of the timeslot according to the data type and operation environment. The number can be configured to be equal to the processing block length of the modem waveform.

2 illustrates a structure of a minislot based timeslot according to an embodiment of the present invention.

MiniSlot_Size of FIG. 2 is a time slot of one minislot, and when one frame is composed of 3100 minislots, MiniSlot_Size = 1 second / 3100 = about 322 μsec. MiniSlot_Count is the number of minislots allocated to the data field among one timeslot, and 3 is the number of minislots allocated to the dummy field.

Referring to FIG. 2, a minislot based timeslot according to an embodiment of the present invention includes a dummy field and a data field.

The dummy field includes at least p minislots for automatic gain control (AGC), preamble, unit word (UW) and guard time settings.
At this time, p is set to 3.

Guard time includes a one-way propagation delay time (eg, 500 μsec) to support the communication distance in the TDMA system and reduces the number of minislots required for the dummy field. Therefore, the central node can set the guard time to the time corresponding to the one-way propagation delay to support the communication distance while minimizing the reduction of resource efficiency due to the propagation delay.

The preamble section may include a preamble pattern for obtaining modem timing and frequency synchronization.

The data field includes dynamic minislots that are allocated in different numbers according to data types and operational environments transmitted and received by the subscribing nodes so that the length of the timeslot is dynamically variable. The number of dynamic minislots allocated to the data field corresponds to an integer multiple of the basic unit of data allocation.In the case of video data, the number of dynamic minislots increases, and in the case of audio data, the number of minislots allocated to the video data is smaller than the number of minislots allocated to the video data. Can be.

When the data allocation basic unit is q mini slots, an integer multiple of q (q> p) is set differently according to the data type and operating environment. Thus, the central node can assign different timeslots of different lengths to each of the subscribing nodes, such that the number of dynamic minislots allocated to the data field varies from subsubscribing nodes to subsequent delay times for subscribing nodes. Can support the transmission speed.

Accordingly, the term 'dynamic' of 'dynamic minislot' means that the number of minislots assigned to the timeslots varies according to the length of the timeslots. Mixed

In an embodiment of the present invention, four minislots are used as data allocation basic units, and the present invention is not limited thereto, and may be added or subtracted according to the environment of the TDMA network or the type of data transmitted and received by the subscriber nodes. For example, when all of the subscribing nodes transmit and receive only voice data or only control data for payload adjustment, the central node may use less than four minislots as a basic data allocation unit.

When the data allocation basic unit is configured with four minislots, the minimum size time slot may be configured with seven minislots. In addition, when extending the length of the timeslot, the central node may further allocate the minislot to the timeslot by an integer multiple of the data allocation basic unit (that is, four). Therefore, the total number of minislots allocated to timeslots is '3 dummy (+ basic data unit integer multiples)', 3+ (4Х2) = 11, 3+ (4Х3) = 15, 19 And so on. In the case of FIG. 1, seven mini slots are allocated to the time slot TS1, 11 to the time slot TS2, and 31 mini slots to the time slot TS3.

3 is a diagram illustrating a resource allocation structure for supporting a maximum transmission rate for each subscription node.

Referring to FIG. 3, when the delay times required by the subscription nodes are all 40 msec equal to the size of the auxiliary frame, the center node should transmit data to each subscription node once every 40 msec. In this case, assuming that the size or type of all the data is the same, the center node may allow the dummy field of the subscription nodes to be allocated to one auxiliary frame once to support the maximum transmission speed for each subscription node. This is because when the dummy enters the auxiliary frame only once for each of the subscribing nodes, the number of minislots for data transmission increases to transmit the most data.

Accordingly, the central node divides 40 msec by the number of subscribing nodes into four timeslots TS1 to TS4 having the same size, and allocates four timeslots to the four subscribing nodes Node1 to Node4, respectively. do. That is, the center node divides the number (124) of the minislots included in one auxiliary frame by the number (4) of the joining nodes, so that the time slots TS1 to 31 of the same number of dynamic minislots (31) are included. TS4) may be allocated to subscribing nodes Node1 to Node4.

From this, one time slot is allocated 31 minislots, 3 of which are dummy minislots, and 28 are minislots for data. In addition, one auxiliary frame includes 124 minislots, 12 of which are for dummy, and 112 (= 124- (3mini slots x 4time slot_count)) are for data.

As a result, the central node can allocate resource to support the maximum transmission speed for each subscribing node based on the auxiliary frame in the TDMA based network operating 4 nodes.

4 is a diagram illustrating a resource allocation structure for supporting a minimum delay time for each subscription node.

Referring to FIG. 4, the center node may allocate resources using a minimum timeslot based on an auxiliary frame in order to support data requiring a minimum delay time for each subscription node.

In detail, the central node allocates the same number of minislots to the data fields for each of the subscribing nodes in order to allocate resources for the minimum delay for each of the subscribing nodes. Allocate 4 minislots. Thus, in the embodiment of the present invention, the central node allocates seven minislots having the minimum size to each subscribing node for the minimum delay time, and equally allocates to each subscribing node, thereby minimizing the transmission delay time. In the case of FIG. 3, if the delay time is 40 msec, in the case of FIG. 4, the delay time is 10 ms.

Hereinafter, an operation using a time slot offset and an operation using a relay timeslot for coverage expansion or shadow area resolution will be described with reference to FIGS. 5 and 6.

5 illustrates a resource allocation structure including a timeslot offset.

Referring to FIG. 5, the central node may allocate a resource including an offset between timeslots in units of mini slots according to the distance between subscription nodes for coverage extension operation.

For example, in FIG. 4, if the maximum communication distance between the center node N1 and the mission node N2 is 150 km and the time set for the guard time to prevent propagation delay by 150 km is 500 μsec, the mission node N2 may guard. By the time (500 µsec), it is possible to prevent a problem that the data transmission time point and the reception time point overlap.

However, if the maximum communication distance is extended from 150km to 200km, if the guard time is maintained at 500μsec, the time required to prevent the actual propagation delay is 500μsec or more, so when the mission node N2 transmits and receives the data The points of overlap will overlap.

Therefore, the central node must reconfigure the time slots as shown in FIG. 5 for such communication distance, that is, coverage extension, and since one minislot is approximately 322 μsec, the minislot is a time slot offset in proportion to the extended communication distance. Can be allocated between the two slots, and the minislot does not contain data. As the communication distance is extended, the delay time is increased, and the number of minislots allocated to the timeslot offset may increase.

6 is a diagram illustrating a resource allocation structure using a relay timeslot.

For example, when the mission node N3 moves to a distance exceeding the maximum communication distance, the central node allocates a relay time slot to support relay, and receives header information of the relay time slot. The relay delay time can be minimized by repeating the timeslot unit.

Referring to FIG. 6, timeslot 1 TS1 is a timeslot allocated by the central node N1 for transmission to the mission node N2, and timeslot 2 TS2 is a task by the center node N1. A timeslot allocated for transmission to node N3, and timeslot 3 TS3 is a timeslot allocated for transmission by mission node N2 to mission node N3. This timeslot map, i.e., scheduling information, is broadcast to mission nodes and shared in advance.

The central node designates a relay node (e.g., mission node N2) for the relay role between the central node N1 and the mission node N3 for coverage expansion and elimination of shadow areas, and a time slot TS2 for relaying. ) Is assigned to the relay node N2, and information about the relay slot (the source node and the destination node N3 as the source and destination information) of the relay slot is included in the header message of the timeslot 2 TS2 of the relay node N2. Information) and data to be relayed to the mission node N3 in the payload.

The relay node N2 analyzes the header message of the received timeslot 2 (TS2) to confirm the source and the destination, and transmits the data to be relayed in the payload of the timeslot 2 (TS2) to the timeslot 3 (TS3). It can be sent to the mission node (N3). Conventionally, the data described in the payload is decoded from the MAC layer to the upper end, decoded, and described in the payload, whereas in the present invention, only the header information is analyzed and the data described in the payload is described in TS3 without decoding. This can further minimize latency.

Meanwhile, the central node according to an embodiment of the present invention may operate multiple center nodes through time slot allocation distribution for each center node of a single TDMA network in configuring a variable timeslot. That is, the central node N1 may designate and distribute mini slots that can be used for each of the plurality of central nodes, thereby configuring time slots using the mini slots designated for each central node to simultaneously operate an independent TDMA network.

In detail, when at least one other central node that manages the entire resource allocation exists in subscribing nodes of one TDMA network, the central node N1 may allow both itself and the other central nodes to share one TDMA network at the same time. The total timeslots or all minislots present in one frame may be divided into groups as many as the number of center nodes and allocated to the center node and one or more other center nodes, respectively. For example, if there is one other center node, since there are two total center nodes, the center node N1 assigns even-numbered timeslots to itself, and odd-numbered timeslots to other center nodes. You can share the network. At this time, the sizes of the timeslots may all be the same or may be different.

Meanwhile, in order to operate a TDMA network, it is necessary to acquire and maintain superframe synchronization, which is a frame synchronization and resource allocation standard for each subscribing node. In case of using 1PPS of GPS, all subscribing nodes can synchronize the starting point of the frame based on 1PPS, and in the time slot structure of the present invention considering only one-way propagation delay, the TDMA network synchronization Can be acquired and maintained.

However, in a situation where GPS cannot be used, acquisition and maintenance of a network synchronizer is necessary through a process of compensating for propagation delay according to the distance between subscribing nodes by configuring initial frame synchronization of a subslot and configuring a separate timeslot. Do.

In order to acquire the initial frame synchronization of the timeslots by the subscribing nodes, the central node according to the embodiment of the present invention is configured by differently configuring the preamble pattern of the first timeslot of the frame and the preamble patterns of the remaining timeslots (ie, by duplexing). In other words, the nodes attempting to join the initial network can acquire the received frame synchronization even in the absence of 1PPS. Acquisition and maintenance of superframe synchronization is possible by the central node further transmitting and receiving the frame number in the header message of the first timeslot of the frame.

First, when using a redundant preamble pattern, the center node is one of a synchronization pattern set in the preamble of the first timeslot of the frame and a general pattern set in the preambles of the remaining timeslots of the frame for synchronization acquisition of the initial frame of each subscribing node. Can be set as a preamble pattern in the dummy field. That is, the center node may set a preamble of the sync pattern for each first timeslot of a frame corresponding to 1 second, and set a general pattern for the remaining timeslots.

When the synchronization pattern is set in the first timeslot of the frame, the mission nodes that receive the synchronization pattern may find the preamble pattern and confirm that it is the first start of the second of the 16 seconds of the superframe, and synchronize the frame.

Next, when using the header, the frame is received once per second, but there is no information for 16 seconds, that is, no information about the superframe. Therefore, when transmitting the timeslot, the ground center node may further display the frame number in the header of the timeslot and transmit the timeslot. The task nodes that have received this can check whether the frame currently received from the frame number of the header corresponds to the number of seconds (that is, the number of frames) of the superframe of 16 seconds. For example, if the frame number identified from the header is 7, then the mission node may recognize that a frame corresponding to 8 seconds is received next and start synchronization.

By duplexing the preamble pattern or enabling the frame to be synchronized using the header, the GPS (Global Positioning System) jamming may occur or operate without a GPS.

7 is a diagram illustrating a state transition diagram of a subscription node for TDMA network synchronization and timeslot control.

Referring to FIG. 7, in the initial state, the subscribing node transitions to a Precise Positioning System (PPS) state when GPS interworking is completed (if GPS_Enable = 1), and otherwise to an IEN state (if GPS_Enable = 0).

The PPS state confirms whether 1pps is normally input, and the joining node initializes the internal timer by 1pps. When 1pps is confirmed to be input normally (0 (if GPS_Lock = 1), the central node transitions to the IEN state.

The IEN state is a state where the subscribing node waits for acquisition of start information of initial frame synchronization and super frame synchronization, and upon receiving the first time slot signal of the central node, initializes an internal timer and transitions to the RTT state (if GPS_Enable = 0). , if Rx_Frame_Synch = 1). If GPS is interlocked, transition to the FINE state (if GPS_Enable = 1, if Rx_Frame_Synch = 1).

The RTT state is a state in which a subscriber node transmits or receives an RTT message using synchronization slot allocation information among resource allocation map information, updates an internal timer (minislot interval counter, etc.) according to the received RTT message information, and updates The time information is applied from the next superframe. After the update is completed, the state transitions to the FINE state (if Tx_Frame_Synch = 1).

In the FINE state, when the internal minislot counter and the slot information coincide by using the slot information for synchronization, transmission and reception among the resource allocation map information, the subscribing node generates a pulse to the modem transmission or reception block, thereby preventing data transmission or reception. To control.

8 is a block diagram illustrating a dynamic timeslot allocation apparatus 800 for resource efficiency in a TDMA system according to an embodiment of the present invention.

Referring to FIG. 8, the dynamic timeslot allocation apparatus 800 according to an embodiment of the present invention may include a resource allocation information generator 810, a resource allocation information processor 820, and a frame generator 830. .

When the resource allocation input information input by the user is input through the graphical user interface (GUI), the resource allocation information generator 810 may analyze the resource allocation input information and generate resource allocation information required for processing in the MAC layer. .

In detail, the resource allocation information generation unit 810 analyzes the input resource allocation input information and dynamically varies the size of the timeslots to be allocated to the plurality of subscribing nodes according to the type of data to be transmitted and the operating environment. The resource allocation information, which is the timeslot map information, may be generated in units of superframes (for example, in units of 16 seconds) by determining the positions of the frames.

The resource allocation input information is, for example, how many mount nodes are operated on a ground node basis, index information of each mount node, Tc (TeleCommand), which is control information transmitted from the ground node to the mount node, or the ground node at the mount node. It includes information such as Tm (TeleMetry), which is the state information to be transmitted, and whether the on-board node and the audio channel are opened or the video channel. In addition, the resource allocation input information, when a relay node is required, performs the operation described with reference to FIGS. 1 to 6 by designating a relay node, information on whether to use a synchronization slot, whether to use a type slot offset, and the number of use. Include the necessary information.

The resource allocation information generation unit 810 determines a size of a time slot to be allocated to subscribing nodes according to a data type and an operating environment based on various communication setting schemes such as bandwidth, modulation scheme, and coding rate of a TDMA network previously set. A resource may be allocated to subscribing nodes by analyzing a predetermined timeslot size and resource allocation input information.

As described with reference to FIG. 2, the resource allocation information generation unit 810 allocates at least p minislots for AGC, preamble, and guard time setting, and different numbers according to data types and operational environments transmitted and received by the subscriber nodes. The structure of the variable timeslot may be generated using dynamic minislots such that the length of the timeslot is dynamically variable. In particular, the resource allocation information generation unit 810 sets an integer multiple of the data allocation basic unit differently according to the data type (for example, video or audio or control data) and the operating environment, and allocates the dynamic minislot to the data field. The number of times may vary for each of the subscribing nodes.

In addition, the resource allocation information generator 810 may generate time slot map information by generating a structure of a variable timeslot in a superframe unit composed of a plurality of frames (for example, 16). Thus, the resource allocation information generator 810 may generate timeslot map information corresponding to the resource allocation information.

In addition, the resource allocation information generation unit 810 is the operation described with reference to FIGS. 3 to 6, that is, a time slot structure for supporting the maximum transmission rate, a time slot structure for the minimum delay time, and a time slot for the time slot offset. A time slot structure using a structure or a time slot for relaying can be generated according to a user's request. Here, the timeslot structure, resource allocation information, resource allocation structure, time information map may be used in the same or similar meanings, and may be used for convenience of description.

In addition, the resource allocation information generation unit 810 may include a time slot structure for sharing a single TDMA network by a plurality of central nodes, a time slot structure for different preamble patterns for frame synchronization, a structure using a header, or a GPS. A time slot structure in which synchronization slots are allocated when synchronization is not possible may be generated according to a user's request.

The resource allocation information processor 820 may generate payload data by receiving data to be transmitted using timeslots based on the timeslot map information.

For example, the resource allocation information processing unit 820 analyzes the resource allocation information input from the resource allocation information generation unit 810, and if the information corresponds to a specific node, for example, the mission node N2, the mission node N2. Find the time slots corresponding to) and generate payload data to load the corresponding data according to the time slots.

The frame generator 830 may generate and transmit a frame by loading the generated payload data in a corresponding time slot among the time slots to be transmitted to the subscription nodes. 3 to 6 illustrate some of the frames generated by the frame generator 830. The frame generator 830 may transmit or receive a frame by loading data of an actual physical layer on a wayform, and may use a field programmable gate array (FPGA).

On the other hand, the operation of the central node (Node1) or the dynamic timeslot allocation apparatus 800 according to the present invention is provided by being included in a recording medium that can be read through a computer by a program of instructions for implementing the type is implemented tangibly It may be understood by those skilled in the art.

That is, the operation of the central node Node1 or the dynamic timeslot allocation apparatus 800 according to the present invention may be implemented in the form of a program that can be performed through various computer means, and recorded on a computer-readable recording medium. The computer-readable recording medium may include program instructions, data files, data structures, etc. alone or in combination. The computer-readable recording medium may include magnetic media such as a hard disk, optical media such as a CD-ROM, and DVD, and ROM, RAM, flash memory, USB memory, and the like. Hardware devices specifically configured to store and execute program instructions are included.

In addition, when an element, component, apparatus, or system is referred to in the present invention as including a component made up of a program or software, the element, component, apparatus, or system, even if not expressly stated, means that the program or It is to be understood that the software includes hardware required for execution or operation (e.g., memory, CPU, etc.) or other programs or software (e.g., an operating system or drivers necessary for running the hardware, etc.).

In addition, it is to be understood that an element (or component) may be implemented in software, hardware, or any form of software and hardware, unless otherwise specified in the implementation of any element (or component).

Accordingly, the present invention provides a program stored in a computer-readable recording medium which is executed on a computer controlling the electromagnetic wave characteristic measuring system to implement the operation of the central node Node1 or the dynamic timeslot allocation apparatus 800.

On the other hand, while described and illustrated in connection with a preferred embodiment for illustrating the technical idea of the present invention, the present invention is not limited to the configuration and operation as shown and described as described above, and depart from the scope of the technical idea It will be apparent to those skilled in the art that many modifications and variations can be made to the present invention without departing from the scope of the invention. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

800: dynamic timeslot allocation unit
810: resource allocation information generation unit
820: resource allocation information processing unit
830: frame generation unit

Claims (8)

In the center node for generating a frame structure for resource efficiency in a time division multiple access (TDMA) system,
A central node of all subscribing nodes subscribed to a TDMA network generates a frame including a plurality of timeslots allocated to all the subscribing nodes at least once per frame,
Each of the plurality of timeslots constituting the frame,
A dummy field including at least p minislots for automatic gain control (AGC), preamble and guard time settings; And
Dynamic minislots are allocated in different numbers according to data types and operational environments transmitted and received by the subscribing nodes to dynamically vary the length of the timeslot, and the number of the dynamic minislots corresponds to an integer multiple of the basic unit of data allocation. A data field;
If there is at least one other central node that manages the entire resource allocation among the subscribed nodes,
The central node is,
The central node is divided into two or more groups by dividing one of all timeslots and all minislots present in the one frame into two or more groups such that the central node and the other one or more central nodes share one TDMA network at the same time. A center node for generating a frame structure for resource efficiency in a TDMA system, characterized in that each of which is assigned to one or more other central nodes.
In this case, p is 3. The method of claim 1,
When the data allocation basic unit is q minislots (q> p), the q integer multiples are set differently according to the data type and operating environment,
The central node is,
Create a frame structure for resource efficiency in a TDMA system, characterized in that the number of dynamic minislots allocated to the data field is variable for each of the subscribing nodes to support independent delay time and transmission rate for each subscribing node. The central node. The method of claim 1,
The central node is,
The frame for resource efficiency in a TDMA system, wherein the one frame corresponding to one second is divided into 25 auxiliary frames, and all the subscribing nodes are allocated one or more timeslots per one auxiliary frame. The central node that creates the structure. The method of claim 3,
In case of resource allocation for supporting the maximum transmission rate for each of the subscribing nodes,
The central node is,
The one auxiliary frame is divided by the number of the subscribing nodes so that the dummy field of the subscribing nodes is allocated to one subframe one time, and the number of the minislots corresponding to the one subframe is the number of the subscribing nodes. Splitting by a number, the central node for generating a frame structure for resource efficiency in a TDMA system, characterized in that the same number of dynamic minislots are allocated to the subscribing nodes. The method of claim 3,
In case of resource allocation for the minimum delay time for each of the subscribing nodes,
The central node is,
The same number of dynamic minislots are allocated to the data field for each of the subscribing nodes, and n minislots, which are the basic units of data allocation, are allocated for the minimum delay time. The center node you create. The method of claim 1,
The central node is,
And a guard node for generating a frame structure for resource efficiency in a TDMA system, wherein the guard time is set to a time corresponding to a unidirectional propagation delay to minimize the reduction of resource efficiency due to the propagation delay. The method of claim 1,
The central node is,
A pattern of a preamble set in the dummy field, among the synchronization pattern set in the preamble of the first timeslot of the frame and the general pattern set in the preambles of the remaining timeslots of the frame in order to obtain synchronization of the initial frame for each subscribing node; A central node for generating a frame structure for resource efficiency in a TDMA system, characterized in that one set. The method of claim 1,
The central node is,
Assign a relay time slot to the relay node by designating a relay node for a relay role between the center node and the mission node among the subscription nodes,
In the header of the relay time slot, information of the central node and the mission node is described as source and destination information, and data to be relayed to the mission node is described in a payload.
The relay node is a central node for generating a frame structure for resource efficiency in the TDMA system, characterized in that the data to be relayed in the payload to the mission node to transmit the data to be relayed in the payload.

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