KR20070076949A - Method for allocating dynamic channels in time division multiple access system and system thereof - Google Patents

Abstract

A method for allocating a dynamic channel in a TDMA(Time Division Multiple Access) system and a system thereby are provided to minimize the power consumption of a mobile terminal by excluding the reception of an unnecessary PDTCH/D(Packet Data Traffic Channel-Downlink) using information a base station provides. A base station confirms whether PDTCH/D and PDTCH/U allocation information exists for the next six RBs(Radio Blocks)(301). If so, the base station confirms whether it is scheduled to allocate a PDTCH/D and a PDTCH/U to a mobile terminal of which the LSB(Least Significant Bit) of the USF(Uplink Status Flag) for the six RBs is '0'(305). If so, the base station allocates PDTCH/Ds and PDTCH/Us to mobile terminals of an even group. Then the base station confirms whether it is scheduled to allocate a PDTCH/D and a PDTCH/U to a mobile terminal of which the LSB of the USF for the six RBs is '1'(307). If so, the base station allocates PDTCH/Ds and PDTCH/Us to mobile terminals of an odd group. If PDTCH/Ds and PDTCH/Us are allocated to all the mobile terminals, the base station sets the stealing flag of a PDTCH/D to '11' and transmits it to each mobile terminal(309).

Description

Dynamic channel allocation method and system according to time division multiple access system {METHOD FOR ALLOCATING DYNAMIC CHANNELS IN TIME DIVISION MULTIPLE ACCESS SYSTEM AND SYSTEM THEREOF}

1 is a diagram showing the same structure of 52 multi-frames in a TDMA system

2 shows the structure of PTCCH / D in a TDMA system;

3 is a flowchart illustrating a dynamic resource allocation method in a base station apparatus of a TDMA system according to a preferred embodiment of the present invention.

4 is a flowchart illustrating a data receiving method in a terminal of a TDMA system according to an embodiment of the present invention.

5 is a block diagram showing a base station according to a preferred embodiment of the present invention.

6 is a block diagram showing a terminal according to a preferred embodiment of the present invention.

7 illustrates an example of a dynamic resource allocation method in a system of the present invention.

The present invention relates to a method and a system for transmitting packet data in a time division multiple access (TDMA) system, in particular a general packet radio system (GPRS) or an enhanced general packet radio system (Enhanced General) Packet Radio System (EGPRS) relates to a dynamic channel allocation method of packet data and a system according thereto.

With the advent of packet data communication in time division multiple access (TDMA) systems, higher flexibility is required in resource allocation, particularly in the use of physical communication channels. Such TDMA systems include GPRS and EGPRS.

In the GPRS / EGPRS mobile communication method, when the packet data is transmitted, the uplink and the downlink use the same structure of 52 multiframes, and the structure is attached. 1 is shown.

Referring to FIG. 1, a frame 100 used in a GPRS / EGPRS mobile communication system includes 52 frames. Each frame 101 has a time interval of 4.615 ms, and each frame 101 is composed of eight consecutive slots. In addition, four frames constitute one radio block (RB) 110, and the multi-frame has a total of 12 radio blocks. Data is transmitted in each of the radio blocks 110, and there is a packet traffic channel (PTCHCH) frame 120 for every 6 radio blocks. The PTCCH frame 120 is used for updating continuous timing advance in the GPRS / EGPRS mobile communication system. According to the uplink and the downlink, it is divided into PTCCH / U and PTTCH / D, respectively. When the terminal transmits a Packet Random Access Channel (PRACH) on the uplink, the base station receiving the channel value sets a Timing Advance value to be applied to each terminal. Use D to inform each terminal.

The structure of the PTCCH / D is shown in FIG. 2.

Referring to Attached 2, the PTCCH / D 200 includes a normal burst, and includes a data field 201 and 207, a still flag 203, and a training sequence 205.

The data fields 201 and 207 contain data traffic, and the training sequence 205 is a field for synchronization. In addition, the still flag 203 is a field for notifying the terminal when the terminal is not in a normal situation, that is, during handover or emergency.

As such, the base station may use fixed allocation, dynamic channel allocation, or extended dynamic channel allocation when allocating PDTCH / U to the terminal. Among these, the dynamic channel allocation method and the extended dynamic channel method can share a single PDTCH / U at the same time, and the base station uses the uplink status flag (USF) of the PDTCH / D. It designates which terminal will use PDTCH / U. If the USF_GRANULARITY value specified when the PDTCH / U is allocated in the dynamic channel allocation method and the extended dynamic channel allocation method is' 0 ', it determines which terminal uses the PDTCH / U for each radio block and the USF_GRANULARITY value is' In case of 1 ', it determines which terminal uses PDTCH / U for every 4 radio blocks. When using the dynamic channel allocation scheme or the extended dynamic channel allocation scheme, all terminals sharing PDTCH / U should check the USF by receiving PDTCH / D in every radio block if the granularity is one radio block. If the granularity is four radio blocks, the USF should be confirmed by receiving PDTCH / D every fourth block.

In the above-described GPRS / EGPRS system, all terminals simultaneously allocated to one PDTCH / U will check to see if the PDTCH / U of the next radio block is assigned to them. That is, the terminal must continuously check the PDTCH / D according to the system. Therefore, even if the PDTCH / D is not allocated to the terminal, the terminal should receive the PDTCH / D of each radio block or the PDTCH / D corresponding to the last radio block of four radio blocks according to the USF_GRANULARITY value. At this time, if the USF is not assigned to itself from the terminal receiving PDTCH / D not assigned to itself, the received PDTCH / D information is not used at all, and as a result, data that does not need to be received receives unnecessary power. Will be consumed.

Accordingly, an object of the present invention is to provide a dynamic channel allocation method and system according to the present invention, which can reduce power consumption in a TDMA system.

The present invention for achieving the above-mentioned is composed of a radio block (RB) consisting of four frame units, constitutes a Packet Traffic Channel (PTCCH) frame between the six RB, 12 In a dynamic channel allocation method for packet data in a TDMA system using 52 RBs, 52 PTTCH frames, and 2 idle frames, a radio block of a predetermined period unit transmitted by a base station belongs to a certain terminal group. A first process of checking whether the mobile station is configured, a second process of the base station setting and transmitting a stealing flag of the PTTCH to set a group of terminals according to the verification result, and a terminal of the received PTTCH And a third process of controlling the reception based on the still flag value.

The present invention for achieving the above-mentioned is composed of a radio block (RB) consisting of four frame units, constitutes a Packet Traffic Channel (PTCCH) frame between the six RB, 12 In a TDMA system using 52 multi-frame standards consisting of RBs, the PTTCH frame, and two idle frames, it is checked to which terminal group a radio block of a predetermined cycle unit to be transmitted belongs, and according to the result, And a base station for setting and transmitting a stealing flag and a terminal for controlling reception based on the stealing flag of the PTTCH.

The base station includes a data queue for temporarily storing data received from an upper node, a control unit for checking information on whether to allocate data to a radio block of a predetermined period to be transmitted, and controlling a scheduler; And a scheduler for setting and scheduling a predetermined still flag and a data processor for modulating the scheduled data.

The terminal receives an RF signal from the base station and converts a baseband signal, an RF (RADIO FREQUENCY) unit, a data queue for temporarily storing the baseband signal, and whether the RF unit is received according to the still flag value. It characterized in that it comprises a control unit for controlling.

The period is characterized in that the unit of six radio blocks.

The still flag value consists of 2 bits.

DETAILED DESCRIPTION Hereinafter, detailed descriptions of preferred embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the same components in the figures represent the same numerals wherever possible. Specific details are set forth in the following description, which is provided to aid a more general understanding of the invention. 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.

The present invention is characterized in that in the TDMA system, even if there is no data allocated to the terminal, unnecessary operations are performed to check whether data traffic is allocated. To this end, two stealing flags of PTCCH / D, designated as 1 and 1, are used on '3GPP TS 45.003 5.2 Packet control channels'. In this case, the base station predetermines the PDTCH / D and the PDTCH / U for the next six radio blocks (RBs) to be transmitted, if possible, and determines two stealing flags accordingly. You will be informed in advance. Accordingly, when the terminal checks the two stilling flags at predetermined periods, the terminal can know whether to receive a predetermined number of radio blocks.

Then, after the dynamic resource allocation method of the present invention will be described, a base station apparatus and a terminal applied to the present invention will be described.

As described above, in the dynamic resource allocation method of the present invention, a terminal allocated for each group according to the two-bit stealing flag determines whether the PDTCH is received during a predetermined frame. The base station allocates the terminal using the least significant bit (LSB) of the USF, which is an allocation code of the terminal. In the following description, for convenience of explanation, it is assumed that it is divided into two groups of even odd numbers. Accordingly, the base station divides the least significant bit (LSB) of the USF, which is an allocation code of the terminal, into '0' or '1' and sets and transmits a still flag of PTCCH / D. The value of the still flag of the present invention is shown in Table 1 below.

Referring to Table 1, the still flag bit is 2 bits, and four cases can be set.

1. If the still flag value of PTCCH / D is '00', the terminal whose LSB of the allocated USF value is '1' does not need to receive PDTCH / D for six radio blocks thereafter.

2. If the still flag value of PTCCH / D is '01', the terminal whose LSB of the allocated USF value is '0' does not need to receive PDTCH / D for six radio blocks thereafter.

3. If the still flag value of PTCCH / D is '10', all terminals do not need to receive PDTCH / D for 6 radio blocks.

4. If the still flag value of PTCCH / D is '11', all terminals must receive PDTCH / U for 6 radio blocks. This is the same as the existing method and can maintain compatibility with the existing system.

3 is a flowchart illustrating a dynamic resource allocation method in a base station apparatus of a TDMA system according to a preferred embodiment of the present invention.

Referring to FIG. 3, the base station apparatus first checks whether there is information on whether PDTCH / D and PDTCH / U are allocated to six radio blocks in step 301. The reason for confirming the PDTCH information for the six radio blocks is because the base station transmits the PTCCH frame in units of six radio blocks in a 52 multi-frame structure. The information confirmation period of the PDTCH may be set differently according to the transmission period of the PTCCH.

If there is no allocation information of the PDTCH in step 301, the base station can not know which terminal group to assign to the base station proceeds to step 309 and sets the still flag of the PTCCH / D to '11' and transmits. However, if there is allocation information of the PDTCH, the base station checks in step 305 whether there is a plan to allocate PDTCJ / D and PDTCH / U to the terminal whose LSB of the USF for the six radio blocks is '0'. That is, it checks whether the terminal is allocated to an even group. When PDTCH is allocated to the even-numbered terminals, it is determined whether PDTCH / D and PDTCH / U are allocated to terminals having LSBs of USR '1' for six radio blocks in step 307. In other words, this time, the allocation of the odd number of terminals is confirmed.

When allocating PDTCH / D and PDTCH / U to all UEs in step 307, the base station transmits by setting the still flag of PTCCH / D to '11' in step 309. Setting the stilling flag to '11' causes all terminals to check whether PDTCH / D or PDTCH / U is received, as shown in Table 1. However, if the terminal is not allocated to the odd-numbered group, the base station proceeds to step 311 and sets the still flag of the PTCCH / D to '00' and transmits it. If the still flag is set to '00', as shown in Table 1, only the even-numbered terminals receiving the PTCCH / D receive the corresponding PDTCH / D or PDTCH / U.

If there is no plan to allocate PDTCH / D and PDTCH / U to even-numbered terminals in step 305, the base station determines in step 313 PDTCH / D and PDTCH to terminals whose LSBs of the USF for the next six radio blocks are '1'. Make sure you assign / D. If only the odd group is assigned after confirmation, the flow proceeds to step 315 to set the still flag of PTCCH / D to '01'. That is, only odd-numbered terminals receive six radio blocks afterwards. If it is not assigned to the odd group after checking in step 313, the process proceeds to step 317 to set the still flag of PTTCH / D to '10' to prevent all terminals from receiving six radio blocks.

Next, a method of receiving and processing allocation information of a PDTCH transmitted from a base station in the system of the present invention will be described with reference to FIG. 4.

4 is a flowchart illustrating a method of receiving and operating a stealing flag transmitted from a base station in a terminal of a TDMA system according to a preferred embodiment of the present invention.

Referring to FIG. 4, the terminal receives the PTCCH / D in units of six radio blocks in step 401 and checks the still flag of the PTCCH / D as in step 403. The terminal confirming the stilling flag confirms whether the PDTCH / D or PDTCH / U to be transmitted later is a group allocated to the terminal. In this case, the checking method is performed by checking the still flag and the LSB of its own USF. For example, when the terminal itself is an even group, if the checked still flag is '00' or '11', it is determined that there is a PDTCH assigned to the terminal, and if it is '01' or '10', it is determined that there is no PDTCH assigned to the terminal. do. In contrast, in the case of an odd group of terminals, if the checked still flag is '01' or '11', it is determined that there is a PDTCH assigned to the terminal, and if it is '00' or '10', it is determined that there is no PDTCH assigned to the terminal. .

In step 405, if the UE determines that the frame to be transmitted thereafter is allocated to itself, then six PDTCH / Ds are received as in step 407. However, if it is not assigned to itself, it does not receive six PDTCH / Ds later.

Next, a base station and a terminal according to the present invention will be described with reference to FIGS. 5 and 6.

5 is a block diagram showing a base station 500 according to a preferred embodiment of the present invention.

Referring to FIG. 5, the base station 500 includes a scheduler 501, a controller 503, a data queue 505, a data processor 507, and an RF unit 509.

The data queue 505 stores data received from an upper node in a queue for each terminal or service. The controller 503 collects information on whether PDTCH / D and PDTCH / U are allocated to a terminal for six radio blocks to be transmitted in the future. Then, the scheduler 501 is controlled according to the allocation to perform the dynamic resource allocation operation according to the present invention. That is, the controller 503 sets the stilling flag according to the present invention in consideration of the information on whether the allocation. And overall control of the remaining functional blocks. The scheduler 501 performs a scheduling operation according to the present invention. In particular, the scheduler 501 sets the still flag of the PTCCH / D frame in the period of the PTCCH / D under the control of the controller 503.

The data processor 507 performs operations such as modulation and demodulation and interleaving of data to be transmitted from the scheduler 501. The RF unit 509 performs an operation such as upconverting to receive the data processed signal and transmit the received signal to the terminal.

6 is a block diagram illustrating a terminal 600 according to an exemplary embodiment of the present invention.

Referring to FIG. 6, the terminal 600 includes an RF unit 603, a controller 605, a data queue 607, and a data processor 609.

The RF unit 603 down-converts the high frequency signal received through the antenna 601 and converts it into a baseband signal. In addition, the control unit 605 maintains the reception standby state for a predetermined time thereafter.

The data queue 607 receives and stores baseband signals, and the controller 605 determines whether to receive six subsequent radio blocks according to the still flag value of PTTCH / D of the data queue 607. Decide Thereafter, if the six radio blocks are not related to the self, the RF unit 603 is controlled to not receive the six radio blocks.

The data processor 609 performs data processing such as demodulation and deinterleaving of the received data. The description thereof will be omitted since the gist of the present invention is not significantly related.

7 is a view showing an example of a dynamic resource allocation method in the system of the present invention. The legend is described first, the empty block 713 represents a radio block that the terminal receives, and the hatched block 715 represents a radio block that the terminal does not receive. In addition, block 717 denotes a PDTCH / D in which a terminal number is X and a USF is assigned to Y in a downlink frame, and block 719 denotes a PDTCH / U in which a terminal number is allocated to Z in an uplink frame.

Referring to FIG. 7, when the terminal receives a still flag value of PTCCH of '00', since only the USFs are even terminals 705 and 709 in six radio block sections 721, the USF is odd. It can be seen that the terminals 707 and 711 are not receiving. When the still flag 703 of the PTTCH received after the six radio blocks is '11', it can be seen that all terminals receive the radio block in the six radio block intervals 723.

Therefore, the base station transmits allocation information about a specific group to the terminal. Accordingly, since the terminal does not receive a frame not related to itself, it is possible to prevent unnecessary power consumption.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, some of the terminals may unnecessarily reduce power consumption of the terminal by not receiving PDTCH / D that does not require reception by using information provided by the base station. In addition, the present invention has the compatibility (Compatibility) with the existing system has no effect on the existing system at all, there is an effect that can be added relatively easily.

Claims (8)

It consists of a radio block (RB) consisting of four frame units, and constitutes a timing traffic channel (PTCCH) frame between the six RBs, the 12 RBs and the PTTCH frame and two In a dynamic channel allocation method of packet data in a TDMA system using 52 multi-frame standards consisting of idle frames, A first step of identifying, to which terminal group, a radio block of a predetermined periodic unit to be transmitted by the base station; A second process of the base station setting and transmitting a stealing flag of the PTTCH to set a group of terminals according to the checking result; And a third process of controlling whether the terminal receives the received flag based on the still flag value of the PTTCH. The method of claim 1, wherein the period, Dynamic channel allocation method characterized in that the unit of six radio blocks. The method of claim 1, wherein the stilling flag value, Dynamic channel allocation method, characterized in that 2 bits. It consists of a radio block (RB) consisting of four frame units, and constitutes a timing traffic channel (PTCCH) frame between the six RBs, the 12 RBs and the PTTCH frame and two In a TDMA system using 52 multi-frame standards consisting of idle frames, A base station for checking which terminal group the radio block to be transmitted in the future belongs to, and setting and transmitting a stealing flag of the PTTCH according to a result; And a terminal for controlling the reception based on the still flag of the PTTCH. The method of claim 4, wherein the base station, A data queue for temporarily storing data received from an upper node; A control unit which checks information on whether to allocate data to a radio block of a predetermined period to be transmitted and controls the scheduler; A scheduler for setting and scheduling a current still flag according to control of the controller; And a data processor for modulating the scheduled data. The method of claim 4, wherein the terminal, An RF (RADIO FREQUENCY) unit for receiving a high frequency signal from the base station and converting a baseband signal; A data queue for temporarily storing the baseband signal; And a control unit controlling whether the RF unit is received according to the stilling flag value. The method of claim 4, wherein the period, System characterized in that the six radio block units. The method of claim 4, wherein the stilling flag value, A system characterized by two bits.

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