KR101081846B1 - A time slot management apparatus and method based on transmission interval in time division multiple access communication system - Google Patents

Abstract

The present invention relates to a time slot management algorithm for allocating time slots in radio resources available to different terminals according to different data transmission period requirements in a time division multiple access (TDMA) communication system. It relates to a method and apparatus that can be used as.

Time Slot Allocation, Time Division Multiple Access, TDMA

Description

A time slot management apparatus and method based on transmission interval in time division multiple access communication system in a time division multiple access communication system

The present invention relates to a method and apparatus for managing a time slot to be allocated according to a transmission period of a terminal using a number of time slot allocation cases in a time division multiple access communication system.

Multiple access means that a plurality of terminal devices transmit a signal in a combined form through one communication line and separate it in the original form at a receiving side, and is for economic use of a limited transmission line. In addition to TDMA, there are FDMA (frequency division multiple access) and CDMA (code division multiple access).

The terminal joining the network requests the network central station for the required amount of radio communication resources according to the amount of data to be transmitted. The network center station allocates an appropriate radio communication resource to the terminal based on the current communication resource utilization status for the terminal request.

The terminal allocated the wireless communication resource from the network center station exclusively uses the corresponding wireless communication resource. When the communication ends, the terminal returns the used wireless communication resource to the network central station again.

A time division multiple access (TDMA) system refers to a case where a unit of the radio communication resource is a time slot. A plurality of base stations are multiplexed through one repeater to divide the same frequency band in time. It refers to a method of communicating with each other so that signals do not overlap, and is a technology mainly used for digital cellular communication.

That is, a method in which several terminals divide a signal in time and transmit a signal only during a time slot allocated to the terminal. According to the present system, a transmission time collision can be prevented by assigning a different time slot to each terminal. .

1 is a conceptual diagram of a time division multiple access system as a prior art.

Referring to FIG. 1, a time division multiple access system includes a time division multiple access network 110, a network center station 120, and terminals 130 and 140, a network center station 120, a first terminal 130, and a first terminal 130. The two terminals 140 are subscribed to the time division multiple access network 110. Network central station 120 includes a timeslot manager 121.

Each terminal transmits information to another terminal through a time division multiple access network. At this time, the network center station 120 receives the transmission period information of the information to be transmitted from the terminal, and the time slot manager 121 transmits the information to the corresponding terminal. Determine if you can assign timeslots. At this time, the time slot to be allocated is determined according to the transmission period of the information to be sent to the other terminal.

As described above, the time division multiple access communication system is advantageous in that it is easy to establish a one-to-many communication network because one radio resource can be divided by time and allocated to multiple terminals. In such a system, a transmission period of information to be transmitted to another terminal is determined according to the size of information to be transmitted by the terminal, which means that as the information to be transmitted by the terminal varies, the transmission period of the information can also vary.

Hereinafter, a process of allocating radio resources to a terminal in a time division multiple access system according to the prior art will be described.

FIG. 2 is a procedure illustrating a process of allocating and retrieving a time slot between a network center station and a terminal according to the related art.

Referring to FIG. 2, first, each terminal 130 or 140 joins the time division multiple access network 110 by performing an initial synchronization acquisition and network joining procedure (S110). The terminals 130 and 140 subscribed to the time division multiple access network 110 communicate with each other through a predetermined time slot among various time slots of the time division multiple access network 110.

For example, when the first terminal 130 joining the time division multiple access network 110 requests the network central station 120 to allocate a time slot, first, the transmission period of information of the first terminal 130 is transmitted. 120) (S120).

The network center station 120 receives this and transmits it to the timeslot manager in the network center station 120 (S130).

The time slot manager selects a time slot that satisfies the requested transmission period based on the current time slot assignment status (S140).

Information on the selected time slot is transmitted to the first terminal 130 through the modem of the network center station 120, the first terminal 130 transmits its information through the assigned time slot (S150).

The terminal performs communication by transmitting information to the network through the timeslot allocated from the network center station 120 (S160).

When the communication is completed, the terminal requests the time slot recovery request to the network center station 120 (S170), and the network recovers the time slots allocated to the terminal.

However, the conventional time division multiple access method divides the data transmission time of one transmission path by a certain time width regardless of the actual amount of data to be transmitted. Since all slots are allocated only to the corresponding terminals, there is a disadvantage in that efficiency is low.

Such a problem can be easily understood with reference to FIG. 3.

3 (a) and 3 (b) illustrate problems of time slot allocation without considering the transmission period when the transmission period is various in the prior art.

According to FIG. 3 (a), for example, in order to transmit information having a 5 second transmission period, the second terminal has a frame size of 10 seconds and slots 0 and 3 are allocated to the first terminal. In case of requesting time slots of 5 second intervals, time slots 1 and 2 cannot satisfy the 5 second transmission period, and thus, time slots cannot be allocated.

On the other hand, as shown in (b) of FIG. 3, when timeslots 1 and 3 are unassigned slots, if the terminal requests a 5 second transmission period, the network center station allocates timeslots 1 and 3 to the terminal 5 Information can be sent every second.

As described above, when the transmission periods are various, the time slots satisfying the requested transmission periods should be selected based on the time slot allocation status. There is a problem that waste of frequency resources may occur.

Accordingly, an object of the present invention is to provide a method for managing time slots through an algorithm using the number of time slot allocation cases when requesting allocation of time slots according to the size of information to be transmitted by a terminal in a request allocation time division multiple access system; An apparatus is proposed.

In order to achieve the above object, the present invention provides a time division multiple access (TDMA) communication system, the time for allocating time slots in the available radio resources according to the various data transmission cycle requirements of different terminals The present invention relates to a slot management algorithm, which provides a method and apparatus for efficiently utilizing timeslots.

The method includes deriving a number of timeslot allocation cases of radio resources according to a transmission period of radio frequency, receiving an information transmission cycle and a timeslot allocation request of radio resources from a terminal, and a number of timeslot allocation cases. Allocating a time slot of the radio resource according to the information transmission period of the terminal by using a time slot allocation optimization algorithm using; receiving the time slot retrieval request from the terminal; and according to the time slot retrieval algorithm Recovering the timeslot allocated to the terminal.

The apparatus derives the number of cases of the time slot allocation of the radio resources according to the transmission period of the radio frequency, the receiver for receiving the information transmission period and the time slot allocation request of the radio resources from the terminal and the optimal time slots according to the optimization algorithm A controller for retrieving the time slot and retrieving the time slot allocated to the terminal using a time slot retrieval algorithm according to the time slot retrieval request received from the terminal where communication has been completed, and a time slot of the radio resource derived from the controller. And a time slot manager for allocating time slots of the radio resources according to the information transmission period of the terminal using the number of allocation cases.

The apparatus transmits transmission period information and timeslot allocation request information to a radio central station and transmits timeslot retrieval request information when communication is over, a receiver for receiving timeslot allocation information from the radio central station, and the timeslot allocation. A time division multiple access terminal device comprising a controller for operating a time slot using information.

According to the present invention, in a time allocation multiple access communication system in which a terminal is allocated a time slot from a network central station, the time slot is variably configured in consideration of the transmission periods of all terminals to be communicated through the time division multiple access network. There is an effect that can efficiently transmit a variety of information of different periods.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding the reference numerals to the respective procedures in the flowcharts of the drawings, the reference numerals to the components in the drawings, or the reference numerals to the components in the drawings, the same procedures and components are different. It should be noted that even though the drawings are shown, the same reference numerals are used as much as possible.

In addition, many specific details appear in the following description, which is provided to help a more general understanding of the present invention, and the present invention may be practiced without these specific matters to those skilled in the art. Will be self-explanatory. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

4 is a block diagram of a request allocation time division multiple access system according to the present invention.

According to FIG. 4, the request allocation time division multiple access system includes a network center station 220, a time division multiple access network 210, terminals 230, 240, a network center station 220, a first terminal 230, and a first terminal. The two terminals 240 are subscribed to the request allocation time division multiple access network 210. The network center station also includes a timeslot manager 221 and a controller 222, and the terminal 230 includes a transmitter 231, a receiver 232, and a controller 233. Each terminal transmits information to other terminals through a time-division time-division multiple access network. At this time, the time slot manager 221 and the controller 222 in the network central station 220 select appropriate time slots according to the information transmission period of the terminal. It is determined whether it can be allocated to the terminal according to the optimization algorithm, and an appropriate time slot is allocated to the terminal.

When the time slot is determined in the controller 222 of the network central station 220 and the time slot is allocated through the time slot manager 221, the terminal receives the time slot assignment information through the receiver 232 to receive the controller 233. Communication is performed by controlling a transmission signal to transmit information in an allocated time slot.

5 is a flowchart illustrating an allocation and retrieval process of timeslots between a network central station and a terminal according to the present invention.

According to FIG. 5, before starting the communication, the controller 222 in the network center station 220 prepares the number identification diagram of the radio resource timeslot allocation case according to the transmission period (S210). This is, of course, possible to create within the controller 222 as well as other devices or timeslot managers.

When the preparation of the number identification diagram in the case of time slot allocation is completed, each of the terminals 230 and 240 joins the time division multiple access network 210 by performing an initial synchronization acquisition and network subscription procedure (S220).

After completing the network subscription procedure, the terminal reports the transmission period of the information to be transmitted to the other terminal to the network central station 220 (S230).

The controller 222 in the network central station 220 searches for an optimal time slot in consideration of the transmission period and time slots allocated by the terminal using an optimization algorithm and reports the searched time slot to the time slot manager 221. (S240).

The time slot manager 221 determines the time slot to be allocated to each terminal by receiving the retrieved time slot (S250).

The network center station 220 allocates the timeslot determined by the timeslot manager 221 to the terminal requesting communication (S260).

The terminal performs communication by transmitting information to the network through the timeslot allocated from the network center station 220 (S270).

After the transmission of the information to be transmitted, the terminal requests the network center station 220 to recover the timeslots allocated to the terminal (S280).

If there is a request for the time slot recovery of the terminal, the network recovers the timeslot allocated to the terminal by the recovery algorithm (S290).

As described above, in the present invention, when one or a plurality of terminals access a request allocation time division multiple access system through an optimization algorithm, a time slot allocation procedure for efficiently using radio resources is performed.

Hereinafter, the basic principle and implementation procedure of the optimization algorithm for time slot allocation according to the present invention will be described in detail.

In order to help the understanding of the present invention, a request allocation time division multiple access system according to the present invention will be described on the assumption that the frame size is 12 seconds, the minimum transmission period is 6 seconds, and the maximum transmission period is 48 seconds. In addition, it is assumed that a message related to timeslot allocation and retrieval is transmitted and received between a network center station and a terminal.

6 illustrates a time slot identification and a number of timeslot allocation cases of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention.

As shown in Fig. 6, one frame consists of four timeslots, which are controlled by the network central station.

Before performing communication with the first terminal, the time slot manager of the network center station initializes the number of allocation cases for each time slot. In this case, the initialization process includes determining which transmission period of messages can be allocated to each time slot. Therefore, before performing communication with the terminal, no time slot is assigned to the identification of FIG. 6.

In this example, since the maximum transmission period is 48 seconds, which is four times the frame, the number of allocation cases is initialized for four frames to generate the timeslot identification and the number of timeslot allocation cases as shown in FIG.

In FIG. 6, 0-X, 1-X, 2-X, and 3-X mean messages having transmission periods of 6 seconds, 12 seconds, 24 seconds, and 48 seconds, respectively.

That is, when a terminal requests a network center station for message allocation having a transmission period of 12 seconds, the network center station selects and assigns a time slot that can most efficiently use radio resources among the time slots from 1-0 to 1-3. do. That is, when one or more arbitrary terminals require time slot allocation at the same time or later, it means that the time slot is selected so that time slots can be allocated to as many terminals as possible.

When the terminal requests a time slot for information having a transmission period of 24 seconds while the time slot manager of the network center station is initialized as shown in FIG. 6, the network center station can maximize radio resource utilization in the current time slot assignment state. Since no time slot is assigned yet, you can select and assign any time slot from 2-0 to 2-7.

Time slots 0-0, 1-0, 2-0, and 3-8 share time slots with each other.

Therefore, in this example, assume that 2-0 is assigned, the timeslots used for 0-0, 1-0, and 3-8 due to the assignment of 2-0 will no longer be allocated due to the assignment of 2-0. It becomes impossible.

This assignment state is shown in FIG.

7 is a time slot 2-0 assigned in a communication system in which a frame size is 12 seconds, a minimum transmission period is 6 seconds, and a maximum transmission period is 48 seconds, according to an embodiment of the present invention. It shows the slot identification and the number of timeslot allocation cases.

In FIG. 7, when another terminal requests time slot allocation for a 24 second transmission cycle message, the time slot manager of the network center station allocates 2-4 out of selectable time slots 2-1 to 2-7. Most advantageous.

The most advantageous reason for choosing timeslots 2-4 here is that 2-0 is already assigned, so only 3-4 and 3-12 timeslots will not be available for future selection. This is because there are relatively many timeslots that can be allocated later.

8 is a time slot identification time slot 2-0 of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention. If is additionally assigned, it shows the time slot identification and the number of timeslot assignment cases that can be allocated later.

As described above, when there is a time slot allocation request for transmitting information of a transmission period of 12 seconds from another terminal, the number of allocation cases of the current 12 second transmission period is from timeslot 1-1 to timeslot 1-3. In case of assigning timeslot 1-1 or timeslot 1-3, the timeslot 1-2 is allocated since the number of timeslots 0-1 is deleted and the timeslot 1-2 cannot be allocated for the 6-second transmission cycle message. It is advantageous to maintain the number of cases of assignment of timeslots 0-1.

9 is allocated timeslots 2-0 and 2-4 in a time slot identification diagram of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention. After that, when a time slot allocation of a 12-second transmission period is required from another terminal, the time slot identification and the number of timeslot allocation cases that can be allocated are shown.

According to the principle described above, the present invention can optimize the time slot allocation for the communication request of the terminal, thereby effectively using the non-dispersed resources. To embody this, the present invention embodies the above principle through the concept of "optimization algorithm". Although the optimization algorithm is implemented through the following method, it will of course be possible to implement the idea of the present invention by using another algorithm that can allocate time slots using the above principle even if the algorithm is not described below.

10 shows an algorithm flow diagram for initializing the identification of the number of timeslot allocation cases according to the present invention. Since the degree of identification of the number of timeslot allocation cases depends on the transmission period of the terminal requesting communication, it is necessary to initialize the identity of the number of timeslot allocation cases previously created in a new communication environment.

The initialization algorithm uses the concept of "double array A" in initializing the identification of the number of timeslot allocation cases. In double-array A, two indexes are used, where the primary index means a transmission period, and the secondary index means the order of the number of allocation cases for each transmission period. In the case of FIG. Table 1 has the meaning. That is, in the present algorithm, the time slots of each identification can be distinguished using a double array A having information on the transmission period and the time slot order in each transmission period. That is, by dividing each time slot from the number identification in the case of time slot allocation, a time slot suitable for a transmission period of information to be transmitted by a terminal connected to a network can be optimally allocated.
Double array A Primary index meaning Secondary index meaning 0 6 second cycle 0 Number of first allocation cases One 12 second cycle One Number of second allocation cases 2 24 second cycle 2 The number of third allocation cases 3 48 second cycle … …
For example, referring to FIG. 6, when trying to determine the number of fourth allocation cases for a 24 second period, 2, the primary index, means a 24 second period, and 3, the secondary index, is a fourth allocation case. Means the number of. In array A, we know the value 6 stored in the primary index 2 and the secondary index 3, where 2-6 is assigned to the primary index 2 and 6 stored in double array A. Will identify the number. That is, in the 24 second period, the number of fourth allocation cases corresponds to 2-6.

Referring to the initialization algorithm of the present invention with the example of FIG. 6 as an example, the number identification diagram of the allocation case of FIG. 6 is stored in the double array A of Table 2 as follows by the initialization algorithm of the present invention. For example, if the number of 12-second transmission cycles is assigned, the number is 1-0, 1-2, 1-1, 1-3, and this value is stored in double-array A. , 1 and 3 are stored sequentially.

Double array A Primary
index Secondary
index value Primary
index Secondary
index value 0 0
One 0
One 3 0
One
2
3
4
5
6
7
8
9
10
11
12
13
14
15 0
8
4
12
2
10
6
14
One
9
5
13
3
11
7
15 One 0
One
2
3 0
2
One
3 2 0
One
2
3
4
5
6
7 0
4
2
6
One
5
3
7

In the timeslot allocation algorithm, the network central station performs an initialization algorithm that identifies the total number of allocation cases before operating the network. For easy understanding of the initialization algorithm according to FIG. 10, the initialization algorithm for the implementation of the present invention is based on the assumption that the slot number S in the frame is 4, the shortest transmission period SP is 6 and the frame size FL is 12. It will be described in detail.

First, in initializing the number identification in the case of allocation, in S301, first, a Num_G value and a Num_L value are designated to generate a double array A.

The cnt_L value is set to 0 by default. Substituting the above values into the S, SP, and FL values shown in S301, the Num_G value is 1, and the Num_L value is 3 in this example.

In S302, the cnt_L value and the Num_L + 1 value are compared. In this example, the cnt_L value is 0 and the Num_L + 1 value is 4, so the two values are different.

In S303, it is determined whether the cnt_L value corresponds to 0. In this example, since the cnt_L value is 0, the process proceeds to S314.

In S314, the cnt_G value and the TempA value are respectively set to 0, and the process proceeds to S310.

S310 is a step of comparing the cnt_G value and the Num_G + 1 value. In the same case, the process proceeds to S315 and in other cases, the process proceeds to step S311. In this example, since the cnt_G value and the Num_G + 1 value are different from 0 and 2, respectively, the process proceeds to S311.

In S311, a value of TempA + cnt_G is calculated. In this example, TempA + cnt_G = 0.

In the next S312, the values of Temp_TempAd are sequentially stored in an array having the primary index of the double array A at 0 with cnt_L = 0 and Temp_TempA = 0. That is, in this example, since the value of Temp_TempA is stored in A [0] [0], A [0] [0] = 0, and the process proceeds to S313.

In S313, 1 is added to the cnt_G value, and the process returns to S310 again.

From S310 to S312, the same procedure described above is repeated. That is, in S312 repeatedly performed in the present embodiment, since cnt_L = 0 and Temp_TempA = 1, the values of Temp_TempA are sequentially stored in an array in which the primary index of the double array A is zero. In the present embodiment, since 0 is already stored in A [0] [0], a new Temp_TempA is stored in A [1] [0] this time. Therefore, A [1] [0] = 1, and A [0 ~ 1] [0] = [0 1], so that the storage of the value corresponding to the primary index 0 in the double array A is completed.

In this case, since the values of cnt_G and Num_G + 1 are equal to 2, and when the flow returns to S310 again through S313, the flow returns to S302 by adding 1 to the existing cnt_L value in S315.

In this example, since the cnt_L value and the Num_L + 1 value are different from 1 and 4 in S302, the flow advances to S303.

In S303, since the cnt_L value is 1, the flow proceeds to S304.

Loop value is 1 in S304, cnt value and cnt_cnt value are set to 0, and the process proceeds to S305.

In S305, a value of TempA [cnt] is specified. In this example, cnt_L is 1 and cnt_cnt is 0, so TempA [0] is 0.

In S306, a value of TempA [cnt + 1] is specified. In this example, TempA [0 ~ 1] = [0 2].

In S307, it is determined whether the loop value is 1, and if it is 1, the process proceeds to S310 through S309, and if not, the process returns to S305 through S308. In this example, since the loop value is 1, the process proceeds to S310.

In S310, as described above, the cnt_G value and the Num_G value are compared. In this example, since the values are different from 0 and 1, the process proceeds to S311.

From S311 to S313, the same procedure as described above is repeatedly performed. In this example, A [0 ~ 1] [1] = [0 2] is stored and Temp_TempA [0 ~ 1] = TempA [0 ~ 1] + 1 = [1 3] is stored. Therefore, since cnt_L value is 1 and Temp_TempA [0 ~ 1] value is [1 3], the value of Temp_TempA is stored in A [2 ~ 3] [1] in an array with the primary index of double array A. Save the Temp_TempA [0 ~ 1] value.

That is, A [2 ~ 3] [1] = [1 3] by the above procedure. A [0 ~ 3] [1] = [0 2 1 3] completes storing the value corresponding to the primary index of 1 in the double array A, thereby initializing the identification of the number of timeslot allocation cases. A kind of unique identification table is formed for each transmission period and subsequent timeslots by array A.

11A, 11B, and 11C show a flowchart of a timeslot allocation algorithm according to the present invention.

In each of FIGS. 11A, 11B, and 11C, uppercase letters “A”, “B”, and “C” mean that the procedure diagrams are connected to each other. That is, each of FIGS. 11A, 11B, and 11C represents one procedure (hereinafter referred to as "FIG. 11" throughout "FIGS. 11A, 11B, and 11C"). First, referring to FIG. 11, in the time slot allocation algorithm using the double array A and the double array B, reading the double array A generated by the initialization algorithm (S402) and initializing the double array B (S403 to S406). ), Continuously monitoring whether a time slot allocation request is received from the terminal (S407), and when a time slot allocation request is received from the terminal, searching whether the network center station can accommodate the request of the terminal through the double-array B; (S408 to S412), determining whether the network center station can accommodate the request of the terminal according to the results of the S409 to S412 (S413), if the network center station can accept the request of the terminal, S409 to The time slot information is generated by using the values stored in the corresponding primary index and the secondary index in the primary index, the secondary index, and the double array A of the one selected in S412, and allocated to the terminal. Steps S413 to S432, wherein the network central station changes the timeslot allocated in the double array B to unavailable (S437 to S443). If the network center station cannot accept the request of the terminal, the request is sent to the requesting terminal. The method may include a step S427 of notifying the time slot allocation failure.

When the double-array A is formed for each of the timeslots of the number identification in the case of time slot allocation, the appropriate time slots should be searched for the request of the terminal. The slot with the smallest number of cases lost by allocation is allocated.

For this purpose, the algorithm uses the concept of "double array B". The primary and secondary indexes of array B have the same meaning as the primary and secondary indexes of array A, and the value stored in array B is the number of available allocation cases (0, if available) 1) if not available. For example, if the primary index is 2, and the secondary index is stored with 6 in double array A and 0 in double array B for 3, this is the fourth allocation of a 24 second period (1 primary index is 2). The number 2-6 of allocation cases corresponding to the number of cases (secondary index equals 3) means that it is currently available.

In the flowchart of FIG. 11, it is determined whether the number of allocation cases corresponding to each transmission period is available through the double array B. FIG. Since there is no slot assigned at initialization, the double array B value is set to 0. When the slot is allocated, the value corresponding to the slot allocated in the double array B is changed from 0 to 1. Therefore, the double array A and the double array B can determine which slots are currently allocated and which slots are available.

In this situation, when the request of the 24 second transmission cycle as shown in FIG. 7, the dual array B determines whether there is an available slot in the 24 second transmission cycle. In this example, all slots except 2-0 are available, so all but B [0] [2] have a value of zero. In this situation, it is determined whether the number of allocation cases of higher transmission periods (12 seconds, 6 second transmission periods shorter than 24 seconds) is available for each available slot. That is, for B [1] [2], the values of B [0] [1] and B [0] [0], which are higher than B [1] [2], are accumulated. Further, for B [2] [2], the values of B [0] [1] and B [0] [0], which are higher than B [2] [2], are accumulated.

Thus, the largest value is selected from the cumulative value of a higher value with respect to the number of assignable cases. In this example, it is most advantageous to allocate B [1] [2] because the cumulative value of the upper value of B [1] [2] is the largest.

If B [1] [2] is selected, it identifies which time slot is determined from the value of A [1] [2] in the double array A and assigns it to the terminal. In addition, when the allocation is performed, the number of cases in which not only the allocated slot but also the upper (short transmission period) of the allocated slot is allocated should be marked as impossible. Therefore, the slot selected in the double array B and its value should be changed from 0 to 1. . In this example, since B [0] [1] and B [0] [0] are already set to 1, there is no change, but only B [1] [2] is changed from 0 to 1.

Hereinafter, the time slot allocation process shown in FIG. 11 will be described in detail.

First, when there is a slot allocation request from the terminal, the transmission period requested by the terminal is stored in step S408. The REQ_L, D, and N values are set in step S409, and in step S410, an array in which the primary index value of the dual array is REQ_L is stored in the array Temp_B. In step S411, the position where 0 is stored in the Temp_B is stored in the usable index (Avail_index), and in step S412, the length of the usable index is stored in the Length_Avail_index.

In step S413, the Length_Avail_index value is determined to be 0, and if it is 0, it informs that the slot cannot be allocated to the requesting terminal (S427). If the Length_Avail_index value is not 0 in S413, the process proceeds to S414, and it is determined whether the Length_Avail_index value is the same as the D value set in S409. In the case of the same value as D, an arbitrary one is selected from the array Avail_index in S426 and the index of the selected value is stored in the index. If the Length_Avail_index value is not D, the array path of Length_Avail_index length is initialized to 0 in S416.

In S417, the Temp_index value is set to the Avail_indec [cnt] value, and in S418, the quotient of dividing the Temp_index value by 2 is stored in the new Temp_index. In S419, it is determined whether the value of B [Temp_index] [Temp_L] is 1, and if it is not 0, it is determined whether Temp_L is 0. If it is not 0, the process moves to S418 again. [cnt] Determines whether the value equals the REQ_L value. In the same case, the Avail_index [cnt] value is stored in the index value. In the other case, an arbitrary one is selected from the array Avail_index through S424, and the index of the selected value is stored in the index value (S425).

In S430 to S432 informs the terminal that the network central station can use the slot at every specific interval (REQ_P) from the SS th slot of the specific (F) frame to the terminal requesting the time slot, and the terminal ID, frame number (F), slot number ( SS), the level REQ_L.

S437 to S443 is a step of changing the double array B, and repeats the steps S438 to S443 to indicate that the time slot allocated from the double array B according to the request of the terminal is changed from 0 to 1 and is not available.

12 is a flowchart of a process of retrieving allocated time slots after communication is completed according to the present invention. First, referring to FIG. 12, after the communication is finished, the process of recovering the allocated time slot includes continuously determining whether the network center station has received the time slot recovery request from the terminal (S503), and the network center station for the recovery of the time slot. Determining the current double array B (S504), the network central station may include the step of changing the value of the place corresponding to the time slot recovered from the double array B from unavailable to available (S511).

When communication between the terminal and the network center station ends, the network center station recovers the timeslots allocated to the terminal.

Referring to FIG. 12, when a terminal returning a slot is allocated the corresponding slot, the terminal notifies the network center of the frame number, slot number, and transmission period indicated by the network center. The network central station reporting the slot number and transmission period performs the retrieval procedure for the slot.

For easy understanding of the invention, it will be described in detail assuming that the terminal requests to return the time slot of the 12 second transmission period.

In S501 and S502, the network central station reads the double array A generated by the initialization algorithm and generates Num_G and Num_L values.

In S503, it is determined whether there is a time slot return request from the terminal, and when there is a return request, the double array B is read in real time in S504.

In S507, the primary index stores the corresponding secondary index having the value of RTN_SEL through the RTN_SEL value. In S508, the cntN value is initialized to 0 and the cnt value and the L value are generated.

In S509, the cnt_N value is compared with the N value, and in S510, a counter of the cnt value and the cnt_N value is incremented by one. The procedures of S509, S510, and S511 are repeated until the value of B [cnt] is set to 0 so that all of the recovered timeslots can be reassigned.

If the value of B [cnt] is reset to 0 for all the timeslots to be recovered, the process proceeds to S512 if the value of cnt_N is equal to the value of N in S509.

The process of S512 to S518 is the same as that of S443 in S437 described above, indicating that the corresponding timeslot is available by changing the double-array B of the recovered timeslot.

  In the above description of the preferred embodiments of the present invention by way of example, the scope of the present invention is not limited to these specific embodiments, the present invention is in various forms within the scope of the spirit and claims of the present invention It may be modified, changed, or improved. In addition, the variables used in the algorithm should not be construed as limiting the scope of the present invention, and will be said to belong to the scope of the present invention even when other variables are used.

1 is a conceptual diagram of a time division multiple access system as a prior art.

FIG. 2 is a procedure illustrating a process of allocating and retrieving a time slot between a network center station and a terminal according to the related art.

3 (a) and 3 (b) illustrate problems of time slot allocation without considering the transmission period when the transmission period is various in the prior art.

4 is a block diagram of a request allocation time division multiple access system according to the present invention.

5 is a flowchart illustrating an allocation and retrieval process of timeslots between a network central station and a terminal according to the present invention.

6 illustrates a time slot identification and a number of timeslot allocation cases of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention.

7 is a time slot 2-0 assigned in a communication system in which a frame size is 12 seconds, a minimum transmission period is 6 seconds, and a maximum transmission period is 48 seconds, according to an embodiment of the present invention. It shows the slot identification and the number of timeslot allocation cases.

8 is a time slot identification time slot 2-0 of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention. If is additionally assigned, it shows the time slot identification and the number of timeslot assignment cases that can be allocated later.

9 is allocated timeslots 2-0 and 2-4 in a time slot identification diagram of a communication system having a frame size of 12 seconds, a minimum transmission period of 6 seconds, and a maximum transmission period of 48 seconds according to an embodiment of the present invention. After that, when a time slot allocation of a 12-second transmission period is required from another terminal, the time slot identification and the number of timeslot allocation cases that can be allocated are shown.

10 is a flowchart illustrating an algorithm for initializing the identification of the number of timeslot allocation cases according to the present invention.

11A, 11B, and 11C show a flowchart of a timeslot allocation algorithm according to the present invention.

12 is a flowchart of a process of retrieving allocated time slots after communication is completed according to the present invention.

Claims (13)

In the wireless communication method, Deriving an identification of the number of timeslot allocation cases of radio resources according to a transmission period; Receiving information transmission period information and a time slot allocation request of the radio resource from a terminal; Performing a time slot allocation algorithm using the transmission period information of the terminal and the identification diagram to search for an assignable slot and assigning the found slot to the terminal; Receiving the timeslot retrieval request from the terminal after communication termination; And Recovering the timeslot assigned to the terminal according to a timeslot retrieval algorithm; The identification of the number of timeslot allocation cases indicates the number of timeslot allocation cases using a primary index representing a transmission cycle and a secondary index representing a sequence number of allocation cases in each transmission cycle. A time division multiple access communication method characterized by deriving using a double array A. The method of claim 1, The time slot allocation algorithm configures an identification of the number of time slot allocation cases, and allocates time slots randomly when there are no allocated time slots. The method of claim 1, The timeslot allocation algorithm constructs an identification diagram for the number of timeslot allocation cases so that when there is a new time slot allocation request while there is already allocated time slots, the available time slots are duplicated according to the new time slot allocation. A time division multiple access communication method comprising allocating timeslots to be the minimum. The method of claim 1, The time slot retrieval algorithm is a time division multiple access communication method using a frame number, a slot number, a transmission period of a time slot allocated to the terminal. delete The method according to claim 1 or 2, The timeslot allocation algorithm includes a double array B indicating whether the number of allocation cases of the longest transmission period is available, and whether the timeslot is assignable using the double array B corresponding to each time slot. And determining and allocating the time slots. In a communication system, A receiver for receiving an information transmission period and a time slot allocation request of a radio resource from a terminal; According to the time slot allocation algorithm for deriving the degree of identification of the number of timeslot allocation of the radio resources according to the transmission period of the radio frequency, and searching for the optimal timeslot based on the transmission period information and the identification of the terminal. A controller for retrieving an optimal timeslot and retrieving the timeslots allocated to the terminals using a timeslot retrieval algorithm according to the timeslot retrieval request received from the terminal upon which communication has been completed; And A time slot manager for allocating time slots of the radio resources according to the information transmission period of the terminal by using the number of timeslot allocation cases of the radio resources derived from the controller; The identification of the number of timeslot allocation cases indicates the number of timeslot allocation cases using a primary index representing a transmission cycle and a secondary index representing a sequence number of allocation cases in each transmission cycle. A time division multiple access communication system characterized by deriving using a double array A. The method of claim 7, wherein And the controller allocates time slots randomly without going through the optimal time slot search procedure when there is a time slot assignment request in the absence of an allocated time slot. The method of claim 7, wherein If there is a new time slot allocation request in the state where there is already allocated time slot, the controller may determine that adjacent time is minimized so that the waste of sigin slots that can be allocated later by the new time slot allocation request is minimized. Time slotted multiple access communication system for retrieving slots and allocating the retrieved timeslots. The method of claim 7, wherein The time slot retrieval algorithm is a time division multiple access communication system, characterized in that using the frame number, slot number, transmission period of the time slot allocated to the terminal. delete 9. The method according to claim 7 or 8, The timeslot allocation algorithm includes a double array B indicating whether the number of allocation cases of the longest transmission period is available, and whether the timeslot is assignable using the double array B corresponding to each time slot. And determining and allocating the timeslots. In the communication terminal device, A transmitter for transmitting transmission period information and timeslot allocation request information to the radio central station and transmitting timeslot retrieval request information when communication is complete; A receiver for receiving timeslot allocation information from the radio central station; And And a controller for operating a timeslot using the timeslot assignment information.

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