KR20080092800A - Method and apparatus for collective byte alignment in mobile communication system - Google Patents

Abstract

A method and an apparatus for aligning collective bytes in a mobile communication system are provided to obtain a length of a collective byte alignment padding without receiving dedicated information on the collective byte alignment padding by adding a predetermined pattern to the collective byte alignment padding. A first protocol device(1005,1010,1015,1020) divides/concatenates upper layer data and outputs a first protocol packet data unit and first protocol header size information. The first protocol header is added into the first protocol packet data unit. A second protocol header and byte alignment padding inserting unit(1025) generates a second protocol header to be added to the first protocol packet data unit, calculates a size of the collective byte alignment padding from the header sizes of the first and second protocol headers, and generates the collective byte alignment padding corresponding to the calculated size. The second protocol header and byte alignment padding inserting unit inserts the collective byte alignment padding at a tail of the second protocol header. A multiplexer(1030) concatenates the second protocol header with the second protocol sub packet data units, which are outputted from the byte alignment padding inserting unit, and outputs a second protocol packet data unit. A physical layer device(1035) transmits the second protocol packet data unit from the multiplexer to a receiver side.

Description

METHOD AND APPARATUS FOR COLLECTIVE BYTE ALIGNMENT IN MOBILE COMMUNICATION SYSTEM}

1 illustrates a conventional collective byte alignment scheme.

2 is a diagram illustrating a first layer and a second layer protocol structure and a PDU structure of LTE.

3 is a signal flowchart for explaining the overall operation of the first preferred embodiment of the present invention.

4 illustrates the structure of a MAC sub-PDU with collective byte alignment padding in the first preferred embodiment of the present invention.

5 is a signal flowchart for explaining the operation of the transmitting apparatus according to the first preferred embodiment of the present invention.

6 is a signal flowchart for explaining the operation of the receiving apparatus according to the first embodiment of the present invention.

FIG. 7 illustrates the structure of a MAC PDU with aggregated byte alignment padding in a preferred embodiment of the present invention. FIG.

8 is a signal flowchart for explaining the operation of the transmitting apparatus according to the second preferred embodiment of the present invention.

9 is a signal flowchart for explaining an operation of a receiving apparatus according to a second preferred embodiment of the present invention.

10 is a diagram showing the structure of a transmitting device according to the present invention;

11 is a diagram showing the structure of a receiving apparatus according to the present invention.

The present invention relates to a method and apparatus for byte-aligning the size of a header in a mobile communication system, and more particularly, to a method in which a size of a header generated in each hierarchical structure is collectively aligned in bytes in a mobile communication system having two or more hierarchical structures. A method and apparatus are disclosed.

In general, aligning the size of a header means adding padding for byte alignment to a header that is not byte aligned. As mobile communication systems become faster, it is important to reduce the processing load by byte-aligning the size of the header.

On the other hand, there are several protocol layers in one mobile communication system, and the byte alignment of the header size for each protocol layer causes excessive overhead in terms of adding padding bits, which are meaningless data for each protocol layer. have. For example, when any mobile communication system is equipped with two protocol layers X and Y, headers generated in the X protocol layer contain X protocol-specific header fields, and the sum of the sizes of these header fields is For example, three bytes and four bits may not be aligned by byte. In this case, the sender byte-aligns the header size of the X protocol layer by inserting byte alignment padding of a predetermined size in the rear part of the header field. The size of the byte alignment padding is derived by Equation 1 below.

In Equation 1, header size x is the size of a header added in the x protocol layer. As in the above example, when the sum of the size of the header fields is 3 bytes and 4 bits, the header size x is 4 bits.

The Y protocol-specific header fields are also added in the Y protocol layer, and if the sum of the sizes of the header fields is not in bytes, byte alignment padding is inserted so that the header size is byte aligned.

As described above, since padding is a sequence of meaningless bits, it is preferable to minimize them as much as possible, so it is not desirable to byte-align headers according to protocol layers.

In 3GPP, which is progressing standardization of Long Term Evolution (LTE), a next-generation mobile communication system using OFDM, in order to overcome the above problem, a method of collectively byte-aligning headers of various protocol layers is under discussion.

The two-layer protocol of the LTE mobile communication system illustrated in FIG. 1 will be described in more detail with reference to a configuration diagram of RLC (Radio Link Control) and MAC (Medium Access Control).

Referring to FIG. 1, byte alignment padding is collectively added to the sum 125 of the headers including the RLC header 110 and the MAC header 105. In other words, it is determined whether the sum of the RLC header and the MAC header is byte aligned, and if not, the byte alignment padding 115 is inserted for the sum of the two headers.

However, the above approach violates the basic principle of layering that any protocol layer device does not actively modify data created in another protocol layer.

2 illustrates a protocol layer structure diagram in an LTE system. Referring to FIG. 2, when LTE layer 1 and layer 2 are composed of an RLC layer 205 to 220, a MAC layer 225, a HARQ device and a physical layer 230, FIG. By inserting byte alignment padding between the RLC header and the RLC payload in the MAC layer device, the MAC layer device violates the basic principle of layering.

For reference, briefly describing the role of each protocol layer of LTE illustrated in FIG. 2, one RLC layer 205 to 220 may be configured per service and include an RLC SDU (235, Service Data Unit), which is data generated from a higher layer. It reconfigures to an appropriate size and attaches a predetermined RLC header 240 to the MAC layer 225. Data transmitted from the RLC layers 205 to 220 to the MAC layer 225 is called an RLC PDU 245. The RLC layers 205 to 220 also perform a reliable transmission of data by performing Automatic Retransmission Request (ARQ) on the RLC PDU.

The MAC layer 225 attaches a predetermined MAC header 250 to the RLC PDU and transmits the MAC header 250 to the HARQ device and the physical layer 230, and the HARQ device and the physical layer 230 transmit the data through a predetermined HARQ operation. Responsible for the operation of transmitting over a wireless channel. The MAC header 250 stores multiplexing information indicating to which RLC device the RLC PDU 245 should be delivered.

As described above, the operation of the RLC layer and the MAC layer may be generalized by inserting a predetermined header into the data transmitted from the upper layer and transferring the same to the lower layer. As described above, the RLC header and the MAC header are collectively byte aligned. In order to achieve this, the MAC layer 225 separates the RLC PDU into an RLC header 240 and an RLC payload 243, and then inserts byte aligned padding at the end of the RLC header. There is a problem that violates the basic principle.

Accordingly, an object of the present invention is to propose a method and apparatus for collectively byte-aligning a header of a higher layer and a header of a lower layer without violating the basic principle of layering. have

It is a further object of the present invention that the collective byte alignment padding may have a predetermined length so that the receiving side can recognize the length of the collective byte alignment padding without receiving separate information on the collective byte alignment padding from the transmitting side. The present invention proposes an apparatus and method for having a pattern.

One embodiment of the present invention for achieving the above object is a method for byte-aligning the header of the first protocol, the upper layer and the second protocol, the lower layer in the transmitting apparatus of the mobile communication system composed of two or more protocol layers And dividing / concatenating the first protocol packet data unit received from the upper layer into an appropriate size, and inserting a predetermined first header to configure the first protocol packet data unit. Constructing a second protocol header for the second protocol header and calculating a size of the collective byte alignment padding from the size of the first protocol header and the size of the second protocol header to generate the collective byte alignment padding of the calculated size. And attaching the second protocol header and the collective byte alignment padding to the first protocol packet data unit. And a process of generating a second protocol sub packet data unit.

Another embodiment of the present invention provides a method for byte-aligning headers of a first protocol that is a higher layer and a second protocol that is a lower layer in a receiving apparatus of a mobile communication system composed of two or more protocol layers. Detecting the last bit of the second protocol header of the second protocol packet data unit to detect the location of the collective byte alignment padding of the second protocol subpacket data unit, and a second protocol header at the second protocol subpacket data unit And generating the first protocol unit by removing the collective byte alignment padding, and delivering the first protocol packet data unit to the corresponding first protocol.

Another embodiment of the present invention provides a method for byte-aligning headers of a first protocol, which is a higher layer, and a second protocol, which is a lower layer, in a transmission apparatus of a mobile communication system composed of two or more protocol layers. Receiving header size information of a unit and a packet data unit of a first protocol, adding a predetermined second protocol header to the packet data unit of the first protocol, and a first protocol packet to which the second protocol header is added. Separating the second protocol header / first protocol header and the first protocol payload from the data unit, concatenating the second protocol header and the first protocol header to form an aggregate header, and Compute the size of the collective byte alignment padding from the size and calculate the aggregated byte definition It comprises the step of adding the separated first protocol payload back of the process and, collectively, byte alignment padding added padding, and delivering the second protocol packet data units to a lower layer.

Another embodiment of the present invention provides a method for byte-aligning headers of a first protocol that is a higher layer and a second protocol that is a lower layer in a receiving apparatus of a mobile communication system composed of two or more protocol layers. Searching for and separating the second protocol header / first protocol header of the unit from the second protocol packet data unit, and adding the sizes of the separated second protocol header / first protocol headers together to collectively align byte padding; Calculating a size of, removing the calculated size from the second protocol packet data unit, separating the first protocol payload using the first protocol payload size information of the second protocol header, and then 1 protocol header together with the corresponding first protocol device.

According to another embodiment of the present invention, an apparatus for byte-aligning and transmitting headers of a first protocol, which is an upper layer, and a second protocol, which is a lower layer of a mobile communication system composed of two or more protocol layers, transmits upper layer data to a predetermined size. And a first protocol packet data unit configured to divide / concatenate into a second protocol, add a first protocol header, and output first protocol header size information, and a first protocol packet data unit received from the first protocol device. A second protocol header to be added to the second protocol header, a size of the collective byte alignment padding is calculated from the sizes of the first protocol header and the second protocol header, and a collective byte alignment padding corresponding to the calculated size is generated; Second protocol header and byte alignment padding inserted after the protocol header and outputted A multiplexer for generating and outputting a second protocol packet data unit by concatenating an inserter, second protocol subpacket data units output from the second protocol header and byte alignment padding inserter, and a second outputted from the multiplexer. It consists of a physical layer device for transmitting two protocol packet data units to a receiving side.

Another embodiment of the present invention provides a reception device for byte-aligning a header of a first protocol, which is an upper layer, and a second protocol, which is a lower layer, of a mobile communication system composed of two or more protocol layers, wherein the second protocol packet data unit is removed. A demultiplexer for dividing and outputting the data into two protocol subpacket data units, and removing the second protocol header from the second protocol service packet data unit, and determining the start bit and the last bit of byte alignment padding to determine byte alignment padding. And a second protocol header and byte alignment padding removal unit for delivering the removed first protocol packet data unit to the corresponding first protocol device.

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The present invention provides a method and apparatus for inserting byte-aligned padding into a later part of a lower layer protocol header in collectively byte-aligning two or more headers so that the lower layer protocol device does not violate the principle of layering. . In particular, the collective byte alignment padding has a predetermined pattern so that a receiver can recognize the length of the collective byte alignment padding without receiving separate information about the collective byte alignment padding from the transmitter.

In one embodiment of the present invention, when collective byte alignment is applied to the first protocol header and the second protocol header, byte alignment padding is inserted at the rear of the second protocol header corresponding to the lower layer. The byte alignment padding has a pattern corresponding to a rule previously promised with the receiver so that the receiver can recognize the length of the byte alignment padding. For example, the remaining bits except the last bit of the collective byte alignment padding are coded as 0, and the last bit of the collective byte alignment padding is coded as 1. However, this is only one embodiment of byte alignment padding, and it is noted that the present invention may include any pattern of byte alignment padding that its length can be recognized at the receiving end.

The receiving side interprets the fields of the second protocol header and takes necessary actions. Upon recognizing that the second protocol header is finished, the receiving side recognizes that the collective byte alignment padding starts from the next bit of the last bit of the second protocol header. The bit corresponding to the first one after the collective byte alignment padding starts is recognized as the last bit of the collective byte alignment padding. The next bit of the last bit of the collective byte alignment padding is recognized as a starting point of the first protocol header. By inserting the collective byte alignment padding at the end of the second protocol header as above, the principle of stratification is observed, and the end bit of the collective byte alignment padding is 1 for the remaining bits of the collective byte alignment padding. By coding zero, there is no need to use extra information to inform the length of the collective byte alignment padding.

In the following description, the first protocol is RLC and the second protocol is described as an example. However, this is only for convenience of description and the present invention can be applied to a communication system composed of two or more layers. It is obvious.

3 is a diagram illustrating a signal flow between a transmitting side and a receiving side according to the first embodiment of the present invention.

In the mobile communication system consisting of the RLC apparatus 302 of the transmitting side, the MAC apparatus 304, the MAC apparatus 306 of the receiving side, and the RLC apparatus 308, the RLC apparatus 302 of the transmitting side is received from an upper layer. RLC PDUs are constructed by cutting or concatenating data into appropriate sizes and attaching RLC headers. In operation 310, the RLC device 302 transmits the size information of the configured RLC PDU and RLC PDU header to the MAC device 304. Here, the header of the RLC PDU may be already byte aligned or may not be byte aligned.

The MAC device 304 configures a predetermined MAC header for the RLC PDU, and calculates the size of the collective byte alignment padding for the MAC header and the RLC header using Equation 2 below.

The transmitting MAC apparatus 304 creates a collective byte alignment padding with reference to the collective padding size in step 320. The collective byte alignment padding is variable in size, with the last bit being coded as 1 and the remaining bits except the last bit being coded as 0. Therefore, the receiving side can distinguish the start and end of the collective byte alignment padding without any additional information. However, depending on whether the size of the collective byte alignment padding is 1, it can be configured as follows.

<How to configure aggregated byte alignment padding>

If the size of the collective padding is 1: Composed padding with 1 bit called '1'

If the size of the collective padding is greater than 1: Code the last bit as '1' and the remaining bits as '0' except the last bit.

As described above, the last bit is coded as 1, and the remaining bits including the start bit are coded as 0, so that the receiver recognizes from the first bit after the end of the MAC header to the bit where the first 1 appears as a collective byte alignment padding. The next first bit of the aggregated byte alignment padding is recognized as the start bit of the RLC header. However, when the RLC header and the MAC header are already byte-aligned collectively, that is, when the size of the collective padding is 0 bits, the receiving device misidentifies the RLC header as the collective byte-aligned padding. To avoid this case, the sender artificially inserts an 8-bit aggregate padding when the aggregated byte alignment padding has a size of 0 so that there is always a collective byte alignment padding.

4 is a block diagram illustrating a configuration of a MAC sub-PDU according to an embodiment of the present invention. Referring to FIG. 4, the transmitting MAC apparatus 304 configures the collective byte alignment padding 410 as described above, and uses the MAC header 405 and the collective byte alignment padding 410 as the RLC PDU 430. Insert before the to create the MAC sub PDU 435. The MAC sub PDU refers to an addition of a MAC header and byte alignment padding to an RLC PDU. A plurality of MAC sub PDUs may be concatenated to configure one MAC PDU.

Referring back to FIG. 3, the transmitting MAC device 304 creates respective MAC sub PDUs from one or several RLC PDUs delivered from one or several RLC devices 302 in step 330, and the MAC sub PDUs. The PDUs are concatenated to form a MAC PDU, which is transmitted to the receiving MAC device 306 in step 340.

The receiving MAC device 306 interprets the MAC header of the first MAC sub PDU of the received MAC PDU, and determines which RLC device to transfer the RLC PDU stored in the MAC sub PDU to. When the last bit of the MAC header is recognized, the bit following the last bit of the MAC header is recognized as the first bit of the collective byte alignment padding, and up to the bit in which 1 appears first is determined as byte alignment padding. For example, if the bit following the last bit of the MAC header is 1, then the aggregated byte alignment padding consists of one bit of '1'. If the bits after the last bit of the MAC header are '0001001100', then the aggregated byte alignment padding is an RLC header such as the first four bits including the first one, '0001', followed by '001100'.

When the MAC header is interpreted as described above and the start and end bits of the collective byte alignment padding are recognized, the MAC receiver 306 removes the MAC header and the collective byte alignment padding from the MAC sub PDU to remove the RLC PDU. After reconstruction, the RLC PDU is transferred to the appropriate RLC device 308 in step 360. If several MAC sub PDUs are stored in the MAC PDU, the MAC receiving apparatus 306 repeats steps 350 and 360 for each MAC sub PDU.

FIG. 5 is a signal flowchart illustrating an operation for performing a collective byte sorting method in a transmitting device configured of an RLC and a MAC in FIG. 3.

In step 505, the transmitting side RLC apparatus 302 divides or concatenates the RLC SDUs received by the upper layer into an appropriate size and inserts a predetermined RLC header to form an RLC PDU. In step 510, the transmitting side RLC device 302 transmits the RLC PDU and the header size of the RLC PDU to the MAC device 304. In step 515, the MAC device 315 configures a MAC header for the RLC PDU received from the RLC layer. The MAC header includes a logical identifier of the RLC device carrying the RLC PDU, size information of the RLC PDU, and the like. In step 520, the MAC device 304 calculates the size of the collective byte alignment padding from the size of the RLC header and the size of the MAC header, which is larger than the sum of the RLC header and the MAC header and the closest byte value and the RLC header. Compute the difference between the sum of the MAC headers and use it as the size of the byte alignment padding.

In step 525, the MAC device 304 checks whether the collective byte alignment padding size (CBAPS) calculated in step 520 is 0 bits. As a result of the checking in step 525, if the size of the byte alignment padding is 0 bits, it means that the RLC header and the MAC header are already byte aligned. In step 530, the MAC device 304 determines that the receiving device has collectively aligned the RLC header. Create an 8-bit collective byte alignment padding called '0000 0001' to avoid mistaken padding.

As a result of the checking in step 525, if the size of the byte alignment padding is not 0 bits, it means that the RLC header and the MAC header are not byte aligned, and therefore, in step 535, the MAC device 304 performs a predetermined number of zeros. Combine 1 to create a collective byte-align padding. The last bit of the collective byte alignment padding is always one. The number of zeros is 1 minus the size of the collective byte alignment padding calculated in step 520. That is, in step 520, if the size of the collective byte alignment padding n is calculated, byte alignment padding is calculated by concatenating 0 of 1 [n-1] bits and 1 of 1 bit.

In step 540, the MAC device 304 attaches the MAC header and the collective byte alignment padding to the RLC PDU to create a MAC sub PDU. In operation 545, the MAC device 304 checks whether another RLC PDU exists. If there is another RLC PDU as a result of the check in step 545, the process proceeds to step 515 and the MAC device 304 repeats the process of configuring the MAC sub PDU from the RLC PDU. On the other hand, if there is no other RLC PDU as a result of the check in step 545, the MAC device 304 proceeds to step 550, the MAC sub PDUs are concatenated to form a MAC PDU, and then the MAC PDU is delivered to a lower layer.

FIG. 6 is a signal flow diagram illustrating an operation for performing a collective byte alignment method in a receiving device composed of the MAC 306 and the RLC 308 of FIG. 3.

When the MAC receiving device 306 receives the MAC PDU from the lower layer in step 610, the first MAC header of the MAC PDU received in step 620 is interpreted. Since the MAC PDU is a concatenation of several MAC sub PDUs, the MAC header of the first MAC sub PDU starts from the first bit of the MAC PDU.

In step 630, the MAC receiving apparatus 306 completes the interpretation of the MAC header of the first MAC sub PDU and recognizes the last bit of the MAC header. In step 640, the MAC receiving device 306 determines whether the aggregated byte alignment padding of the first MAC sub PDU is inserted over which bits to which bits. The MAC receiving device 306 first recognizes the first bit of the collective byte alignment padding. The first bit of the aggregated byte alignment padding is the next bit after the last bit of the MAC header. The MAC receiving apparatus checks bit by bit from the first bit including the first bit of the collective byte alignment padding, and recognizes the first 1 as the last bit of the collective byte alignment padding. And bits between the first and last bits, including the first and last bits of the collective byte alignment padding, as collective byte alignment padding. In step 650, the MAC receiving device 306 removes the MAC header and the collective byte alignment padding from the MAC sub PDU to form an RLC PDU, and then transfers the RLC PDU to the appropriate RLC device 308 in step 660.

In step 670, the MAC receiving apparatus checks whether there is a remaining MAC sub PDU. If there is a remaining MAC sub PDU as a result of the check in step 670, the MAC receiving apparatus repeats the operation of extracting the RLC PDU from the MAC sub PDU in step 620. However, if the MAC sub PDU no longer exists as a result of the checking of step 670, the MAC receiving apparatus proceeds to step 640 and waits until the next MAC PDU is delivered.

In the first embodiment of the present invention as described above, the collective byte alignment padding is inserted after the MAC header, thereby enabling the collective byte alignment while observing the principle of layering. By using '1' as the last bit of the collective byte alignment padding, the start and end of the collective byte alignment padding are indicated without any additional information. However, a disadvantage of the first embodiment is that in the situation where the collective padding of the MAC header and the RLC header has already been made, 8-bit collective byte alignment padding is unnecessary.

The principle of stratification is not an absolute norm that must be observed unconditionally, but a reasonable recommendation to be observed. Therefore, if the expected gain is large, it is possible to violate the principle of layering, and we can often see cases where the principle of layering has been violated in many protocols, such as header compression protocols, that are currently in the commercialization stage.

In a second embodiment of the present invention, a method and apparatus for collectively byte-aligning RLC headers and MAC headers of a plurality of RLC PDUs are provided on the assumption that the principle of layering may be violated. As the number of headers byte aligned together increases, the gain of the collective byte alignment also increases. In the second embodiment, the RLC headers and MAC headers of all RLC PDUs multiplexed into one MAC PDU are placed in the same region. Add byte-aligned padding collectively for the headers. An example thereof will be described in more detail with reference to FIG. 7.

Referring to FIG. 7, an arbitrary MAC transmitting apparatus multiplexes three RLC PDUs, such as RLC PDU 1 705, RLC PDU 2 710, and RLC PDU 3 715, into one MAC PDU at an arbitrary time point. Assume the case. Here, the MAC transmitter adds predetermined MAC headers 720, 725, and 730 to the RLC PDU 1, RLC PDU 2, and RLC PDU 3. The MAC header and RLC headers 735, 740, and 745 of the respective RLC PDUs are separated from the RLC payloads 750, 755, and 760 to fill the MAC header and RLC headers from the front of the MAC PDU. When all the headers are stored, the collective byte alignment padding 747 is obtained by using the following equation for the entire header, and the collective byte alignment padding 747 is added.

Following the collective byte alignment padding, the MAC transmitting apparatus receives RLC payloads 750, 755, and 760 in the order in which the MAC header / RLC header is stored. Thus, by extending the range of collective byte alignment to the MAC headers and RLC headers of all RLC PDUs contained in the MAC PDU, only one collective byte alignment is independent of the number of RLC PDUs contained in any MAC PDU. By just padding you can achieve byte alignment.

8 is a signal flowchart illustrating the operation of the MAC transmitting apparatus according to the second embodiment of the present invention.

In step 810, the MAC transmitting apparatus receives the RLC PDU and header size information of the RLC PDU from the RLC layer. In step 820, the apparatus for transmitting a MAC adds a predetermined MAC header to the RLC PDU. As described above, the MAC header stores information necessary for the MAC receiver to demultiplex the RLC PDUs from the MAC PDU and then deliver the RLC PDU to the appropriate RLC device, that is, the identifier of the RLC device and the length information of the RLC PDU. . In the second embodiment of the present invention, the size information of the RLC payload is stored in the MAC header instead of the length information of the RLC PDU. The MAC transmitting apparatus uses a limit value of the RLC header in the size of the RLC PDU received from the RLC layer as the size information of the RLC payload.

In step 830, the MAC header and the RLC header and the RLC payload are separated from the RLC PDU to which the MAC header is added. That is, the MAC transmitting apparatus recognizes as many bits as the RLC header from the first bit of the RLC PDU as the RLC header, and recognizes the rest of the RLC PDU except the RLC header as the RLC payload. The RLC payload is separated from the RLC PDU to which the MAC header is added.

In operation 840, the apparatus for transmitting a MAC checks whether an RLC PDU to be multiplexed together with the RLC PDU exists. If another RLC PDU is multiplexed together with the RLC PDU as a result of the check in step 840, the process proceeds to step 810 to receive the RLC PDU and the RLC header size information from the RLC layer, adds the MAC header, and adds the RLC payload. Repeat the disconnecting operation.

However, if the RLC PDU to be multiplexed as a result of the check in step 840 no longer exists, the MAC transmitting apparatus proceeds to step 850 to concatenate the MAC header and the RLC headers to form a collective MAC header. For example, when n RLC PDUs from any RLC PDU [1] to RLC PDU [n] are multiplexed into one MAC PDU, the collective MAC header of the MAC PDU includes the MAC header of the RLC PDU [1]. In the RLC header, the MAC header and RLC header of the RLC PDU [n] are stored in a predetermined order.

In operation 860, the apparatus for transmitting MAC calculates the size of the collective byte alignment padding by referring to the size of the collective MAC header. That is, the size of the closest byte-aligned size larger than the size of the aggregated MAC header is calculated, and the value obtained by subtracting the size of the aggregated MAC header from the byte-aligned size is recognized as the size of the aggregated byte alignment padding, Append a zero to the end of the collective MAC header.

In step 870, the MAC apparatus stores the RLC payload after the collective byte alignment padding in the order in which the MAC header and the RLC header are stored in the collective MAC header. When all of the RLC payloads are received, the MAC PDU is delivered to the lower layer in step 880.

9 is a signal flowchart illustrating the operation of the MAC receiving apparatus according to the second embodiment of the present invention.

In step 910, the MAC receiving apparatus receives a MAC PDU. In step 920, the MAC receiving apparatus recognizes the first bit of the MAC PDU as the first bit of the first MAC header / RLC header and separates the first MAC header / RLC header from the MAC PDU. In step 930, the MAC receiving apparatus determines whether another MAC header / RLC header exists in the MAC PDU. As a result of the determination in step 930, if there is another MAC header / RLC header in the MAC PDU, the process proceeds to step 920, and the MAC receiver separates the next MAC header / RLC header from the MAC PDU and proceeds to step 930 again. However, if it is determined in step 930 that no other MAC header / RLC header is present in the MAC PDU, in step 940, the MAC receiving apparatus sums all sizes of MAC header / RLC headers separated from the MAC PDU to collectively arrange bytes. Compute the size of the padding and remove the aggregated byte alignment padding from the MAC PDU.

In step 950, the MAC receiving apparatus separates the RLC payload by referring to the RLC payload size information of the associated MAC header in the collective payload portion of the MAC PDU, and then transfers the RLC payload to the appropriate RLC device with the associated RLC header in step 960. . The association between the RLC header, the MAC header, and the RLC payload is determined according to the order in the collective header part and the collective payload part. That is, the n th RLC header / MAC header of the collective header part is associated with the n th RLC payload of the collective payload part.

In step 970, the MAC receiving apparatus checks whether an RLC payload remains in the collective payload part. If the RLC payload remains in the collective payload part as a result of the inspection of step 970, the process proceeds to step 950 to separate the RLC payload and deliver it to an appropriate RLC device. However, if the RLC payload does not remain in the collective payload part as a result of the inspection of step 970, it waits until another MAC PDU is received although not shown in the figure.

10 is a block diagram illustrating an internal configuration of a transmission apparatus according to the present invention.

Referring to FIG. 10, a transmitting device includes a plurality of RLC devices 1005, 1010, 1015, and 1020, a MAC header and a collective byte alignment padding inserter 1025, a multiplexer 1030, a HARQ device, and a physical layer device ( 1035).

The RLC apparatus 1005, 1010, 1015, and 1020 configures an RLC PDU by dividing or concatenating upper layer data into an appropriate size, adding an RLC header, and then padding the RLC PDU and RLC header size information with MAC header and byte alignment padding. Transfer to insert portion 1025.

The MAC header and byte alignment padding inserter 1025 creates a MAC header to be added to the RLC PDU, and then calculates the size of the collective byte alignment padding by referring to the size of the RLC header and the MAC header. After the collective byte alignment padding corresponding to the calculated size is created, the collective byte alignment padding is inserted after the MAC header in the first embodiment and after the collective MAC header in the second embodiment.

In the first embodiment, the multiplexer 1030 concatenates the MAC sub PDUs with the MAC header and the collective byte alignment padding inserted therein into MAC PDUs, and then converts the MAC PDUs to the HARQ device and the physical layer device 1035. To pass.

In the second embodiment, the multiplexer 1030 concatenates the collective MAC header, the collective byte alignment padding, and the payload into a MAC PDU, and then transfers the MAC PDU to the HARQ device and the physical layer device 1035. The HARQ device and the physical layer device 1035 transmit a MAC PDU to a receiver through a predetermined HARQ process.

11 is a block diagram illustrating an internal configuration of a receiving apparatus according to the present invention.

The receiving device includes a plurality of RLC devices 1105, 1110, 1115, and 1120, a MAC header and byte alignment padding removal unit 1125, a demultiplexer 1130, a HARQ device, and a physical layer device 1135. The HARQ device and the physical layer device 1135 receive the MAC PDU through a predetermined HARQ process and transmit the MAC PDU to the demultiplexer 1130.

In the first embodiment, the demultiplexer 1130 divides the MAC PDU into MAC sub-PDUs and transfers the MAC PDUs to the MAC header and byte alignment padding remover. In the second embodiment, the demultiplexer 1130 divides the MAC PDU into a collective MAC header and a MAC payload and transfers the MAC PDU to the MAC header and byte alignment padding remover 1125.

In the first embodiment, the MAC header and byte alignment padding removal unit 1125 removes the MAC header from the MAC service PDU, and removes byte alignment padding by determining the start bit and the last bit of the byte alignment padding. The resulting RLC PDU is then transferred to the appropriate RLC device. In the second embodiment, the MAC header and byte alignment padding remover 1125 separates the collective MAC header into individual MAC header / RLC header pairs. And removes the collective byte alignment padding from the collective MAC header. It also removes the MAC header from the individual MAC header / RLC header pair and then delivers the RLC header and associated RLC payload to the RLC device.

As described above, the present invention has the advantage that the header of the upper layer and the header of the lower layer can be byte aligned collectively without violating the basic principle of layering. In addition, since the collective byte alignment padding has a predetermined pattern in advance, the receiving side can recognize the length of the collective byte alignment padding without receiving separate information on the collective byte alignment padding from the transmitting side. There is an advantage.

Claims (20)

A method for byte-aligning headers of a first protocol, which is a higher layer, and a second protocol, which is a lower layer, in a transmitting device of a mobile communication system composed of two or more protocol layers, Dividing / concatenating the first protocol packet data unit received by the upper layer into an appropriate size, and inserting a predetermined first header to configure the first protocol packet data unit; Configuring a second protocol header for the first protocol packet data unit; Calculating the size of the collective byte alignment padding from the size of the first protocol header and the size of the second protocol header to generate the collective byte alignment padding of the calculated size; And attaching the second protocol header and the collective byte alignment padding to the first protocol packet data unit to generate a second protocol subpacket data unit. The method of claim 1, wherein the collective byte alignment padding is A method of collective byte sorting of headers in a transmitting device, characterized in that the size is generated in a pattern corresponding to a predetermined rule that can recognize a size upon reception. 3. The method of claim 1 or 2, wherein the last bit of the collective byte alignment padding is And the remaining bits are padded with zeros. The method of claim 1, And wherein the first protocol is RLC and the second protocol is MAC. The method of claim 1, wherein the second protocol header is And a logical identifier of the first protocol that generated the first protocol packet data unit and size information of the first protocol packet data unit. The method of claim 1, wherein the aggregated byte alignment size is A collective value of headers in a transmitting apparatus, wherein a difference between a minimum byte value larger than a sum of sizes of the first protocol header and the second protocol header and a sum of the sizes of the first protocol header and the second protocol header Byte sorting method. The method of claim 1, And checking whether the size of the calculated byte alignment padding is 0 bit, and when the size of the byte alignment padding is 0 bit, generating 8-bit aggregate byte alignment padding. Collective byte alignment method in the header. A method for byte-aligning headers of a first protocol, which is a higher layer, and a second protocol, which is a lower layer, in a receiving device of a mobile communication system composed of two or more protocol layers, Detecting the position of the collective byte alignment padding of the second protocol subpacket data unit by detecting the last bit of the second protocol header of the second protocol packet data unit received from the lower protocol; Generating a first protocol unit by removing a second protocol header and aggregated byte alignment padding from the second protocol subpacket data unit; And forwarding the first protocol packet data unit to the corresponding first protocol. 9. The method of claim 8, wherein detecting the location of the collective byte alignment padding A method of collective byte alignment of a header in a receiving apparatus, characterized in that the size of the collective byte alignment padding is recognized according to a rule previously agreed with the transmitting side. 10. The method of claim 8 or 9, wherein the location of the collective byte alignment padding is Collective byte alignment method of the header in the receiving device, characterized in that the first bit in the next bit of the last bit of the second protocol header A method for byte-aligning headers of a first protocol, which is a higher layer, and a second protocol, which is a lower layer, in a transmitting device of a mobile communication system composed of two or more protocol layers, Receiving header size information of the first protocol packet data unit and the packet data unit of the first protocol, and adding a predetermined second protocol header to the packet data unit of the first protocol; Separating the second protocol header / first protocol header and the first protocol payload from the first protocol packet data unit to which the second protocol header is added; Concatenating the second protocol header and the first protocol header to form an aggregate header; Calculating the size of the collective byte alignment padding from the size of the collective header and adding the calculated aggregated byte alignment padding; And adding the separated first protocol payload after the aggregated byte alignment padding, and delivering the second protocol packet data unit to a lower layer. 12. The method of claim 11, wherein the second protocol header is And a first protocol identifier. The method of claim 29, wherein the header comprises a first protocol identifier. 12. The method of claim 11, wherein the second protocol header is And the length information of the first protocol packet data unit or the first protocol payload size information. 12. The method of claim 11, wherein the aggregate header byte sort size is And a difference between the minimum byte value larger than the aggregated header size value and the aggregated header size value. A method for byte-aligning headers of a first protocol, which is a higher layer, and a second protocol, which is a lower layer, in a receiving device of a mobile communication system composed of two or more protocol layers, Retrieving a second protocol header / first protocol header of a second protocol packet data unit and separating from the second protocol packet data unit; Summing all the sizes of the separated second protocol headers / first protocol headers to calculate the size of the collective byte alignment padding, and removing the calculated size from the second protocol packet data unit; And separating the first protocol payload by using the first protocol payload size information of the second protocol header, and then transferring the first protocol payload together with the associated first protocol header to the corresponding first protocol device. Collective byte alignment method on the device. An apparatus for byte-aligning and transmitting headers of a first protocol, which is an upper layer, and a second protocol, which is a lower layer, of a mobile communication system composed of two or more protocol layers, A first protocol device for dividing / concatenating upper layer data into a predetermined size and outputting a first protocol packet data unit and first protocol header size information configured by adding a first protocol header; A size calculated by generating a second protocol header to be added to the first protocol packet data unit received from the first protocol device, and calculating the size of the collective byte alignment padding from the sizes of the first protocol header and the second protocol header. A second protocol header and byte alignment padding inserter which generates a collective byte alignment padding corresponding to and inserts and outputs after the second protocol header; A multiplexer which generates a second protocol packet data unit by concatenating second protocol subpacket data units output from the second protocol header and byte alignment padding inserter, and outputs the second protocol packet data unit; And a physical layer device for transmitting the second protocol packet data unit output from the multiplexer to a receiving side. The method of claim 16, wherein the multiplexing unit And generating a second protocol packet data unit by concatenating the collective second protocol header, the collective byte alignment padding, and the payload, and outputting the second protocol packet data unit. A receiving device for byte-aligning headers of a first protocol, which is an upper layer, and a second protocol, which is a lower layer, of a mobile communication system composed of two or more protocol layers, A demultiplexer for dividing and outputting a second protocol packet data unit into a second protocol subpacket data unit; Removing a second protocol header from the second protocol service packet data unit, and determining a start bit and a last bit of byte alignment padding to transfer the first protocol packet data unit from which byte alignment padding has been removed to a corresponding first protocol device. And a protocol header and byte alignment padding removal unit. 19. The method of claim 18, wherein the demultiplexer is And receiving a second protocol packet data unit into a collective second protocol header and a second protocol payload. 17. The apparatus of claim 16, wherein the second protocol header and byte alignment padding remover Separate the collective second protocol header into separate second protocol header / first protocol header pairs, remove the collective byte alignment padding from the collective second protocol header, and from the separate second protocol header / first protocol header pair And remove the second protocol header.

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