WO2008041296A1

WO2008041296A1 - Wireless communication apparatus

Info

Publication number: WO2008041296A1
Application number: PCT/JP2006/319549
Authority: WO
Inventors: Noriaki Takahashi; Shigeru Shinohara
Original assignee: Fujitsu Limited
Priority date: 2006-09-29
Filing date: 2006-09-29
Publication date: 2008-04-10

Abstract

In an RLC layer in the protocol layer structure of a wireless communication system, in a case of converting an SDU from an upper layer to a PDU, an LI of 15 bits is reduced by, for example, three bits down to 12 bits, and these three bits are used to introduce a remaining identifier RI that is information indicative of the statuses of the octets of the tail of the SDU and the subsequent octets. In addition, without using the LI, a header expansion area is provided with the values of a novel definition indicating that the tail of the SDU is coincident with the tail of the PDU and that the tail of the SDU ends with the tail of the PDU minus one octet and the tail octets are a padding. This can solve the problem that an insertion of the LI indicative of the tail of the SDU causes the tail of the SDU to be excluded. Further, it becomes possible to determine, from the current PDU, that the tail of the SDU is included in the current PDU and to determine, from the current PDU, the statuses of the octets of the tail of the SDU and the subsequent octets without awaiting a reception of the next PDU.

Description

Specification

Wireless communication device

Technical field

TECHNICAL FIELD [0001] The present invention relates to a wireless communication apparatus having a function of dividing or combining first data items into a second data unit in data transfer between protocol layers of wireless communication, and more particularly to wireless communication. In the RLC layer belonging to layer 2 that constitutes the protocol layer, this relates to a wireless communication device that performs communication processing when the end of the SDU is included in the PDU.

Background art

[0002] The protocol layer in a wireless communication system such as W-CDMA is composed of a physical layer (layer 1), a data link layer (layer 2), and a network layer (layer 3). Layer 2 is MAC (Medium

Access Control) and RLC (Radio Link Control). Each layer is specified by 3GPP, and RLC is a communication protocol specified by 3GPP TS25.322.

[0003] Figure 1 shows RLC PDU (Protocol Data

2 is a diagram showing a format of (Unit). The RLC PDU (hereinafter referred to as PDU) shown in Fig. 1 is an Acknowledge that allows data acknowledgment control and retransmission control.

The PDU header is a D / C bit that distinguishes between user data and control data, and a sequence number (SN (Sequence

Number)), polling bit P indicating presence / absence of delivery confirmation request, HE (Header Extension) area indicating user data extension information, length indicator (Length

Indicator) With LI and E (Extension) bits, data and padding bits in the data area P AD or Piggybacked

STATUS PDU) is stored.

[0004] The data size of the PDU is fixed to, for example, 42 oct, 82 oct, 122 oct (loct (octet) is 8 bits), and is not changed during communication. The PDU is identified by the sequence number SN and The Kens number SN is given a number from 0 to a maximum of 4095, for example.

[0005] In the RLC of Fig. 1, the RLC transmission side is fixed by dividing, combining, and padding variable-length RLC SDUs (Service Data Units) (hereinafter referred to as SDUs) transmitted from higher layers. Convert to long PDU. Since the SDU size is variable, when the SDU is divided or combined into fixed-length PDUs, the end position of the SDU does not necessarily match the end position of the PDU. Therefore, if the end position of the SDU is present in the PDU, a length indicator LI is added to the PDU as header information to indicate the end position.

[0006] The number of LI bits may be 7 bits (substantially 1 octet) or 15 bits (substantially 2 octets), and either one operates according to an instruction from an upper layer. However, since LI is usually 15 bits, the following description will be made with an example of operation with 15 bits. Whether LI is present in the PDU depends on the HE (Header

It is indicated by the value in the Extension) area.

FIG. 2 is a diagram showing a pattern of conventional PDU generation processing. 02 (A) is the case where the SDU data does not end with the last octet of the current PDU and continues. In this case, L I is not inserted. As an example, a PDU has a fixed length of 12 octets. If the header area does not contain LI, the header area is 2 octets and the data area is 10 octets. Each time the PDU includes the end of the SDU and a 2-octet LI is inserted to indicate it, the data area is decremented by 2 octets.

[0008] Figure 2 (Α ') shows the case where the last segment data of the SDU data matches the last octet of the current PDU. In this case, the LI indicating that the end of the SDU ends with the end octet of the PDU cannot be inserted. If LI is inserted, the last segment data of the SDU will not end with the last octet of the PDU. Therefore, conventionally, as shown in Fig. 7 (b) described later, LI "0x0000" indicating that "SDU ended in accordance with the last octet of the previous SN PDU" is set to the header area of the next PDU. Insert into. In this case, there is a problem that it is not possible to determine that the SDU ends with the current PDU until the next PDU is received.

[0009] FIG. 2 (B) shows a case where the SDU data ends with the last octet-1 of the current PDU and padding is inserted into the last octet. In this case as well, since there is the end of the SDU in the PDU, it is necessary to insert an LI to indicate the position. If an LI with 2 octets is inserted, On the contrary, 1 octet is not enough. Therefore, without inserting the LI indicating the end position of the SDU, the last segment data of the S DU is stored up to the last octet of the PDU—padding is inserted into the remaining one octet, and the LI is inserted into the header area of the next PDU. Insert "0x7FFB". LI "0x7FFB" means that "SDU ended in accordance with the last octet 1 of the previous PDU. The remaining 1 octet is padding" as shown in Fig. 7 (b). Also in this case, it is not possible to recognize that the end of the SDU is included in the current PDU! /, Until the next PDU containing Ll “0x7FF B” is received.

[0010] 02 (C) is the case where the end of the SDU is included in the current PDU, and the end of the SDU and the end of the PDU match by inserting the LI indicating the end position of the SDU. In this case, the end position of the SDU can be determined from the current PDU, and no padding is inserted, so there is no problem.

[0011] Figure 2 (D) shows the case where the end of the SDU is included in the current PDU, and when a 2-octet LI indicating the end position of the SDU is inserted, the last 1 octet is left and padding is inserted there. It is. In this case, it is not possible to insert a LI that indicates that the last 1 octet is padding. In this case, a normal LI value indicating the end position of the SDU is inserted, and padding is inserted into the remaining 1 octet. In the header area of the next PDU, `` SDU matches the end octet of the previous PDU. LI "0x7FFB" is inserted to indicate that the remaining 1 octet is padding.

[0012] Therefore, there is a problem that until the next PDU is received, it cannot be determined whether the last octet of the current PDU is padding or the leading data of the next SDU.

[0013] Figure 2 (E) shows that when the end of an SDU is included in the current PDU and a 2-octet LI indicating the end position of the SDU is inserted, the last 2 octets are left, and there is segment data for the next SDU. Is inserted. The end position of the SDU is indicated by LI, and no padding is inserted, so there is no problem.

[0014] Figure 2 (F) shows the case where the end of the SDU is included in the current PDU, and when the 2-octet LI indicating the end position of the SDU is inserted, the last 2 octets are left and padding is inserted there. It is. However, in practice, LI indicates that the remaining octets are padding.

By inserting “0x7FFF”, the end of the SDU matches the end of the PDU, and the padding is Although not entered, LI "" 0x7FFF "assumes that 0 octet padding is inserted.

[0015] 02 (G) is the case where the end of the SDU is included in the current PDU, and when a 2-octet LI indicating the end position of the SDU is inserted, the last 2 octets are left and padding is inserted there. is there. In this case as well, as in Fig. 2 (F), the force to insert LI "0x7FFF" indicating that the octet is 2 octets of LI and the remaining octets are padding Ll "0x7FFF" j Even if is inserted, the last one octet is left, so padding is inserted there.

[0016] FIG. 2 (H) shows a case where the last segment data of SDU # 1 ends with the current PDU, and the entire next SDU # 2 ends with the last octet of the current PDU. In this case, LI indicating the end position of SDU # 1 is inserted force. LI indicating the end position of SDU # 2 cannot be inserted! /. Therefore, there is a problem that it cannot be determined that the next SDU # 2 will end in the current PDU.

[0017] 02 (1) is the case where SDU # 1 ends with the current PDU, and the next entire SDU # 2 ends with tail octet-1 of the current PDU. In this case, the LI indicating the end position of the SDI cannot include the LI indicating that the end of the next SDU # 2 is included and the end octet is padding. Therefore, there is a problem that it cannot be determined that the next SDU # 2 will be terminated in the current PDU.

[0018] In FIG. 2 (J), SDU # 1 ends with the current PDU, and the entire next SDU # 2 is also included in the current PDU, and LI indicating the end positions of SDU # 1 and SDU # 2 is displayed. This is the case when the end of SDU # 2 and the end of the PDU match. In this case, the end position of SDU # 2 can also be determined from the LI of the current PDU, and no problem occurs.

[0019] In FIG. 2 (K), SDU # 1 ends with the current PDU, and the entire next SDU # 2 is also included in the current PDU, and LI indicating the end positions of SDU # 1 and SDU # 2 is displayed. This is the case when padding is inserted there after the last one otatsukato S. In this case, it is not possible to insert a LI that indicates that the last 1 octet of padding is inserted into the 2 octets of LI that indicate the end positions of SDU # 1 and SDU # 2. In this case, LI "0x7FFB" is inserted in the header area of the next PDU, indicating that "SDU ended with a match with the last octet of the previous PDU. The remaining 1 octet is padding." Therefore, there is a problem that it cannot be determined whether the last octet of the current PDU is padding or the head data of the next SDU after SDU # 2. [0020] In Patent Document 1 below, in a wireless packet communication system configured to include one access point and a plurality of terminals, a terminal that transmits a packet to the access point receives a packet next to the access point. Is characterized in that next packet information indicating the size of the next packet to be transmitted or the presence or absence of the next packet is added to the packet.

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-67115

Disclosure of the invention

Problems to be solved by the invention

[0021] The above problems are summarized as follows. That is,

(1) If the end of the SDU and the end of the PDU match, the LI indicating that there is an end of the SDU cannot be inserted into the current PCU containing the end of the SDU, and is inserted into the next PDU. For this reason, the end of SDU cannot be determined from the current PDU power, but only from the LI of the next PDU! /.

[0022] (2) When the SDU ends with the last octet of the PDU—when padding is inserted in the last octet, the end of the SDU and the rest is padding. It cannot be inserted into the current PDU, but is inserted into the next PDU. For this reason, the end of the SDU cannot be determined by the current PDU power, and it can be determined only from the LI of the next PDU that the last octet is padding (not the first data of the next SDU).

[0023] (3) If the SDU ends in the last octet of the PDU—when padding is inserted in the remaining octets, a LI can be inserted into the current PDU indicating that there is an end of the SDU. LI indicating that is a padding cannot be inserted and will be inserted in the next PDU. For this reason, only the LI of the next PDU can determine that the last octet is padding (not the first data of the next SDU)! /.

[0024] Thus, even if the RLC receiving side receives the current PDU with the end of the SDU, it can recognize that the end of the SDU is included in the current PDU until the next PDU is received. In other words, processing is delayed and complicated.

[0025] For example, even if the current PDU has already been received, if the next PDU cannot be received and is retransmitted, processing of the PDU that follows the current PDU is continued until the next PDU is received. Data transfer delay increases.

[0026] FIG. 3 is a diagram showing processing when the next PDU after reception of the current PDU is retransmitted. R The LC receiver (receiver's wireless communication device) receives PDUs sequentially. The end of SDU # 1 is the power contained in PDU # 3. LI indicating that PDU # 3 has the end of SDU # 1 is included in the next PDU # 4. Therefore, when PDU # 3 is received, SDU # 1 is completed, but the completion cannot be recognized until PDU # 4 is received and the LI included in it is acquired. At this time, if the next PDU # 4 cannot be received due to a data error or the like and a retransmission is requested, the completion of SDU # 1 cannot be recognized until PDU # 4 is received after PDU # 9 of SDU # 3 is received. Originally, although PDU # 1 to PDU # 3 including all segment data of SDU # 1 were received normally, the effect of retransmission of PDU # 4 of SDU # 1 unrelated to SDU # 1 Therefore, the transfer to the upper layer is greatly delayed.

[0027] Further, as a further problem, (4) when there is no subsequent SDU, it is necessary to generate an additional PDU including only the LI indicating that there is a tail (not including SDU data), and the traffic volume is reduced. Increase

[0028] Therefore, even in the cases (1) to (3) above, RLC control is performed so that the PDU including the end of the SDU includes information (for example, LI) indicating the PDU. It is an object of the present invention to provide a wireless communication apparatus that enables this.

Means for solving the problem

[0029] A first configuration of the wireless communication apparatus of the present invention for achieving the above object is to receive a variable-length first data unit at a predetermined layer constituting a wireless communication protocol layer, and In a wireless communication device that converts one data unit to one or more fixed-length second data units, the received data size of the first data unit is the data size of the free data area of the second data unit. If larger, the dividing means for dividing the first data unit into a plurality of segment data in accordance with the data size of the empty data area of the second data unit, and the entire received first data unit or the plurality of data The data size of the last segment data of the segment data is one octet larger than the data size of the empty data area of the second data unit. If the first data unit ends with a value indicating that the last octet of the second data unit is one octet before and the last octet of the second data unit is padding, And a control means for setting in a predetermined area of the header area of the data unit. [0030] A second configuration of the wireless communication apparatus according to the present invention is characterized in that, in the first configuration, the predetermined area is a header extension area of a protocol data unit.

[0031] A third configuration of the wireless communication apparatus of the present invention is a predetermined layer that constitutes a protocol layer for wireless communication, receives a variable-length first data unit, and receives one first data unit. Or, in a wireless communication device that converts to a plurality of fixed-length second data units, if the data size of the received first data unit is larger than the data size of the empty data area of the second data unit, A dividing means for dividing the first data unit into a plurality of segment data in accordance with the data size of the empty data area of the second data unit; and the received first data unit or the plurality of segment data The end of the last segment data is included in the free data area of the second data unit, and the end of the end of the last segment data is included in the header area of the second data unit. If the indicator indicating the position is included, the remaining identifier indicating the type of data stored in the remaining free area of the second data unit after the end is set in the predetermined area of the header area of the second data unit. And a control means.

In a fourth configuration of the wireless communication apparatus of the present invention, in the third configuration, the predetermined area in which the remaining identifier is set is a part of an area assigned to the indicator, and the remaining The end position can be indicated by the area.

[0033] A fifth configuration of the wireless communication apparatus of the present invention is the same as the fourth configuration described above, wherein the empty data area of the second data unit includes the entire first data unit or a plurality of the last segment data. If the indicator indicating the position of each end is included, a remaining identifier indicating the type of data stored in the remaining free space of the second data unit is set in a part of the area of the last indicator. It is characterized by that.

[0034] According to a sixth configuration of the wireless communication apparatus of the present invention, in the third configuration, the remaining identifier has at least a first type of data stored in a remaining free area of the data unit. It is characterized by identifying whether the whole data unit, segment data of the first data unit or padding data.

[0035] A seventh configuration of the wireless communication apparatus of the present invention is the above-described remaining configuration in the third configuration. The bespoke means that at least the first data unit, the segment data of the first data unit, the padding data or the entire first data unit and the end of the data type stored in the remaining free space of the data unit are It is characterized by identifying whether it is a combination of paddings inserted in octets.

[0036] In an eighth configuration of the wireless communication apparatus of the present invention, in any one of the first to seventh configurations, the first data unit is provided in a layer 2 constituting a protocol layer for wireless communication. It is a service data unit (SDU) transmitted / received in the RLC layer to which it belongs, and the second data unit is a protocol data unit (PDU) transmitted / received in the RLC layer.

The invention's effect

[0037] According to the present invention, in the wireless communication apparatus on the transmission side, the indicator indicating the end position of the first data unit is inserted into the header area of the second data unit. The dilemma that the end of the data unit is not included in the second data area can be resolved.

[0038] Further, the receiving side wireless communication apparatus can determine completion of the first data unit from the current second data unit without waiting for reception of the next second data unit. it can. Also, the type of data after the end of the first data unit included in the current second data unit can be determined without waiting for the reception of the next second data unit. Therefore, even if reception of the next second data unit is delayed due to the retransmission processing of the next second data unit, the completion of the first data unit can be determined from the current second data unit. The assembled first data unit can be quickly transferred to the upper layer, and the transfer delay can be shortened.

[0039] Since an additional indicator that does not need to insert an indicator indicating the end position of the previous second data unit is generated in the next second data unit, the amount of communication data can be reduced accordingly. , Do not press the communication band.

Brief Description of Drawings

FIG. 1 is a diagram showing a format of RLC PDU (Protocol Data Unit).

FIG. 2 is a diagram showing a pattern of conventional PDU generation processing. FIG. 3 is a diagram showing a process when the next PDU after receiving the current PDU is retransmitted.

FIG. 4 is a configuration diagram of a wireless communication apparatus in an embodiment of the present invention.

FIG. 5 is a diagram showing a PDU format in the embodiment of the present invention.

FIG. 6 is a diagram for explaining the definition of RI in the embodiment of the present invention.

FIG. 7 is a diagram illustrating the definition of LI in the embodiment of the present invention.

FIG. 8 is a diagram for explaining the definition of the HE region in the embodiment of the present invention.

FIG. 9 is a diagram showing a pattern of PDU generation processing in the embodiment of the present invention.

FIG. 10 is a diagram showing a process when the next PDU after receiving the current PDU is retransmitted in the embodiment of the present invention.

FIG. 11 is a diagram for explaining a delay in SDU transfer to a higher layer than in the first example.

FIG. 12 is a diagram for explaining the delay of SDU transfer to a higher layer than in the second example. Explanation of symbols

[0041] 10: Radio communication terminal device, 20: Radio base station device, 11: RLC transmission control unit, 12: RLC reception control unit, 21: RLC transmission control unit, 22: RLC reception control unit

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment does not limit the technical scope of the present invention.

[0043] FIG. 4 is a configuration diagram of the wireless communication apparatus according to the embodiment of the present invention. The wireless communication device is the wireless communication terminal device 10 or the wireless base station device 20, and the wireless communication terminal device 1

0 and the radio base station apparatus 20 are RLC transmission control units 11 and 21 and RLC reception control unit 12, respectively.

22 is provided.

[0044] In the RLC layer, the RLC transmission control units 11 and 21 divide the SDU from the upper layer into one or more segment data (if the SDU is smaller than the data size of the PDU, It has a function of converting into a PDU (in combination) and a function of resending the PDU subject to the retransmission request based on a retransmission request from the receiving side.

[0045] RLC reception control units 12 and 22 assemble SDUs from received PDUs in the RLC layer, and

A function that makes a retransmission request for a function to transfer to a higher layer and a PDU that cannot be received. Have the ability. The embodiment described below is the control in the RLC transmission control units 11 and 21, and the RLC transmission control units 11 and 21 are provided with the dividing means and the control means in the present invention.

[0046] In the case of downlink communication, the radio base station apparatus 20 is the radio communication apparatus of the present invention, and in the case of uplink communication, the radio communication terminal apparatus 10 is the radio communication apparatus of the present invention. Hereinafter, the RLC transmission control unit 11 of the radio communication terminal apparatus 10 will be described as an example, but the embodiment of the present invention is similarly applied to the RLC transmission control unit 21 of the radio base station apparatus 20. The RLC transmission control units 11 and 12 and the RLC reception control units 12 and 22 may be configured by deviations of hardware, software, or a combination of both.

[0047] In the embodiment of the present invention, the remaining identifier RI (Rest

(Indicator) (3 bits) is defined.

FIG. 5 is a diagram showing a PDU format in the embodiment of the present invention. In the header area of the PDU, the conventional 15-bit LI is reduced to 12 bits, and the 3-bit RI area is concatenated to the final LI. Since the maximum size of a PDU is 5000 bits, the maximum number of octets in the data area when LI is inserted is

5000 / 8-2 = 62 l = 0x26D

Since 10 bits can indicate the end of the SDU, a maximum of 5 bits can be reduced, so it is no problem to reduce LI by 3 bits to 12 bits.

[0049] Then, in the header area of the PDU, the content of the remaining data area after the position indicated by LI is determined by RI concatenated with the final LI (E bit is determined by "0"). Show. If the remaining data area is only padding, or Piggybacked

(STATUS PDU) is also indicated by RI.

FIG. 6 is a diagram for explaining the definition of RI in the embodiment of the present invention. As shown, five RI values are defined. Specifically, RI “000” is defined as “the rest of the position indicated by the LI value is SDU segment data”, and RI “001” is “the rest of the position indicated by the LI value is padding” RI "010" is defined as "the rest of the position indicated by the LI value is the entire SDU", and RI "011" is the "the rest of the position indicated by the LI value is the entire SDU. However, the last octet Is defined as “padding”, and RI “100” is defined as “the rest of the position indicated by the LI value is Piggybacked STATUS PDU”. The remaining values are reserved values (Reserved). The processing using each RI will be described later.

[0051] In addition, by introducing the RI characteristic of the present invention, the conventional special LI value becomes unnecessary, and the LI value is purely a pointer indicating the position in the PDU.

FIG. 7 is a diagram for explaining the definition of LI in the embodiment of the present invention. FIG. 7 (a) shows only the LI (normal LI value) used in the embodiment of the present invention, and FIG. 7 (b) shows the LI used in the embodiment of the present invention and the conventional LI. FIG. 5 is a diagram including a special LI that has been used and that is not used in the embodiment of the present invention. The special LI values “0x0000” and “0x7FFA”, “0x7FFB”, “0x7FFE”, and “0x7FFF”, which are conventionally used as shown in Fig. 7 (b), are no longer necessary, and the SDU from the next octet in the header area Only the normal LI value indicating the number of octets to the end is used (see Fig. 7 (a)).

[0053] In the embodiment of the present invention, an unused value is newly defined in the HE area of the header area of the PDU. Of the 2-bit area allocated to the HE area, according to the 3GPP definition, the upper bits are not currently used as "Reserved". Therefore, a new definition is added to indicate that the end of the SDU matches the end of the PDU using this upper bit. This makes it possible to indicate that the end of SDU without inserting LI matches the end of PDU, and inserts LI indicating that the end of SDU matches the end of PDU as before. This eliminates the dilemma that the end of the SDU does not match the end of the PDU.

FIG. 8 is a diagram for explaining the definition of the HE region in the embodiment of the present invention. As shown in Fig. 8, the values "00" and "01" are already defined values. In addition to this, a new value "10" is followed by the entire SDU or the end of the SDU. This is segment data and defines that the end of the PDU and the end of the SDU match.The value "1 Γ" is followed by the octet that follows the entire SDU or the last segment data of the SDU, and the end of the SDU is from the end of the PDU. There is up to 1 octet, the last 1 octet is padding ”. Processing using this HE region value will be described later.

FIG. 9 is a diagram showing a pattern of PDU generation processing in the embodiment of the present invention. Corresponds to Figure 2. This processing is executed by the RLC transmission control units 11 and 21. Figure 9 (A) shows the case where the SDU data does not end with the last octet of the current PDU and continues. Since the SDU is larger than the data area of the PDU, the SDU is divided into multiple segment data and non-final segment data is stored in the PDU. In this case, there is no problem and it is the same as Fig. 2 (A).

[0056] Figure 9 (Α ') shows the case where the last segment data of the SDU matches the last octet of the current PDU. In this case, by setting “10” in the HE area of the header, it is possible to indicate that the end of the SDU ends with the end octet of the PDU without inserting an LI.

[0057] The value “10” in the HE area is defined as “the entire SDU or the last segment of the SDU after the following octet”, and a 2-octet LI indicating that the end of the SDU is the end of the PDU. It can be shown that the end of the SDU without insertion is the end of the PDU. Since LI is not inserted, the dilemma that the end of SDU does not coincide with the end of PDU by inserting LI is also resolved. On the receiving side (corresponding to RLC reception control units 12 and 22), it is possible to determine that the end of the SDU is the end of the PDU by reading the value “10” in the HE area. In addition, it is not necessary to insert a special LI value (see Fig. 7) indicating that the previous PDU has the end of the SDU in the next PDU. This solves the problem in Fig. 2 (Α ').

[0058] Figure 9 (iii) shows the case where the SDU ends with the last octet-1 of the current PDU and padding is inserted into the last octet. In this case, by setting “11” in the HE area of the header, it is possible to indicate that the SDU without inserting the LI ends with the last octet-1 of the current PDU and that the last octet is padding.

[0059] The value “11” in the HE area is defined as “the entire SDU or the last segment of the SDU after the following octet, and the last one octet is padding”, and the value “11” in the HE area is used. By doing so, it is possible to indicate that the SDU without inserting a 2-octet LI ends with the last octet of the current PDU, and that the last octet is padding. Since LI is not inserted, the dilemma that the end of SDU does not coincide with the end of PDU by inserting LI is also resolved. On the receiving side (corresponding to RLC reception control units 12 and 22), it is possible to determine that the end of the SDU is the end of the PDU by reading the value “11” in the HE area. In addition, a special LI value (see Figure 7) indicating that “the previous PDU has the end of SDU” is inserted in the next PDU. There is no need. This eliminates the problem in Figure 2 (B).

[0060] Fig. 9 (C) shows the case where the end of the SDU is included in the current PDU, and the end of the SDU and the end of the PDU match by inserting the LI indicating the end position of the SDU. In this case, there is no problem because the SDU end position can be determined from the current PDU by inserting a 2-octet LI that indicates the end position of the SDU, and no padding is inserted.

[0061] RI "001" is defined as "the rest of the position indicated by the LI value is padding", and there is no padding, but it is assumed that padding of 0 octets is inserted. The RI is inserted in concatenation with each LI, and only the RI of the final LI (LI with E bit = 0) is valid, as described later.

[0062] Figure 9 (D) shows the case where the end of the SDU is included in the current PDU, and when a 2-octet LI indicating the end position of the SDU is inserted, the last 1 octet is left and padding is inserted there. It is. In this case, RI “001” that is linked to the 2-octet LI indicating the end position of the SDU is also inserted. The last octet of the PDU is padding. With RI "001", it can be determined that the last octet after the LI value is padding. In addition, it is not necessary to insert a special LI value (see Fig. 7) indicating that "the previous PDU has the end of SDU" in the next PDU. This eliminates the problem in Figure 2 (D).

[0063] Figure 9 (E) shows that when the end of the SDU is included in the current PDU and a 2-octet LI indicating the end position of the SDU is inserted, the last 2 octets are left, and there is segment data for the next SDU. Is inserted. In this case, a 2-octet LI indicating the end position of the SDU is inserted, and the RI “000” to be linked to it is set.

[0064] RI “000” is defined as “the remainder of the position indicated by the LI value is an SDU segment”, and the octet after the LI value (last 2 octets) stores the segment of the next SDU. Can be determined. When LI is set, the last 2 octets of the PDU become the next SDU segment.

[0065] Figure 9 (F) shows the case where the end of the SDU is included in the current PDU, and when the 2-octet LI indicating the end position of the SDU is inserted, the last 2 octets are left and padding is inserted there. It is. In this case, insert an LI of 2 octets indicating the end position of the SDU, and insert “001” to connect to the LI. By inserting LI, the last 2 octets of the PDU are padded. RI “001” can be used to determine that the last two octets after the LI value are padding. Togashi.

[0066] Figure 9 (G) shows the case where the end of the SDU is included in the current PDU, and when 2 octets of LI indicating the end position of the SDU are inserted, there is an extra 2 octets and padding is inserted there. It is. In this case, as in Fig. 9 (F), a 2-octet LI indicating the end position of the SDU is inserted, and RI “001” connected to the LI is inserted. Also, depending on the LI setting, the last 3 octets of the PDU are padding. With RI “001”, it is possible to determine that the last 3 octets after the LI value are padding.

[0067] FIG. 9 (H) shows a case where the last segment data of SDU # 1 ends with the current PDU, and the entire next SDU # 2 ends with the last octet of the current PDU. In this case, set RI “010” to be linked to LI indicating the end position of SDU # 1. Since RI “010” is defined as “the rest of the position indicated by the LI value is the entire S DU”, the octet after the LI value is the entire next SDU # 2, and the end of the SDU # 2 It can be determined that the end of the PDU matches. As a result, the problem shown in FIG. 2 (H) can be solved.

[0068] FIG. 9 (I) shows a case where SDU # 1 ends with the current PDU, and the next SDU # 2 as a whole ends with the last octet-1 of the current PDU. In this case, set RI “011” to be linked to LI indicating the end position of SDI. RI “011” is defined as “the rest of the position indicated by the LI value is the entire SDU. However, the last one octet is padding”, so the entire S DU # 2 following the octet after the LI value is defined. (SDU # 2 ends with the last octet of the PDU) and it can be determined that the last octet is padding. As a result, the problem shown in Fig. 2 (1) can be solved.

[0069] Figure 9 (J) shows that SDU # 1 ends with the current PDU, and the entire next SDU # 2 is also included in the current PDU, and LI indicating the end positions of SDU # 1 and SDU # 2 is displayed. This is the case when the last one octet is left after insertion, and padding is inserted there. The LI indicating the end position of SDU # 1 is inserted, and the LI indicating the end position of the next SDU # 2 is inserted, so that the entire SDU # 2 ends with the end octet of the current PDU. Each LI is linked to RI.

[0070] Since the E bit of LI indicating the end position of SDU # 1 is "1", the RI linked to the LI is not considered and an arbitrary value is given. When the LI E bit is "1", a further LI is set after the LI in the header area. The RI of the present invention is linked to the final LI. The definition is valid only for one RI, and no other RI is considered.

[0071] The E bit of LI indicating the end position of SDU # 2 is "0" indicating the final LI, and Rl "001" is set. RI “001” is defined as “the rest of the position indicated by the LI value is padding”, and there is no padding, but it is assumed that padding of 0 octets is inserted.

[0072] In FIG. 9 (K), SDU # 1 ends with the current PDU, and the entire next SDU # 2 is also included in the current PDU, and LI indicating the end positions of SDU # 1 and SDU # 2 is displayed. This is the case when padding is inserted there after the last one otatsukato S. In this case, the LI indicating the end position of SDU # 1 is inserted, and further, the LI indicating the end position of the next SDU # 2 is inserted, so that the entire SDU # 2 ends with the end octet 1 of the current PDU. , Padding is inserted in the last octet.

[0073] As described above, since the E bit of LI indicating the end position of SDU # 1 is "1", the RI connected to the LI is not considered and an arbitrary value is given. When the E bit of LI is "1", a further LI is set after that LI. The definition of the RI of the present invention is valid only for the RI linked to the final LI, so other RIs are not considered.

[0074] The E bit of LI indicating the end position of SDU # 2 is "0" indicating the final LI, and Rl "001" is set. RI “001” is defined as “the rest of the position indicated by the LI value is padding”, and it can be determined that the last octet after the LI value is padding. This eliminates the problem in Figure 2 (K).

As described above, in this embodiment, (1) 15-bit LI is reduced by 3 bits, for example, and 12 bits are used to indicate the state of octets after the end of the SDU. Introduce some remaining identifier RI. (2) Furthermore, without using LI, the end of the SDU matches the end of the PDU, and the end of the SDU ends at the end of the PDU—one octet, and the new octet is padding. Give a value of the proper definition to the HE area. This eliminates the problem that the end of the SDU is not included by inserting the LI indicating the end of the SDU, and that the end of the SDU is included in the current PDU and that the octet after the end of the SDU The status (padding power, SDU segment data, etc.) can be determined from the current PDU card without waiting for the next PDU to be received. Also, a special LI other than the LI indicating the end position of the SDU is not required. [0076] Further, when there is no subsequent SDU, it is possible to suppress an increase in the amount of communication that does not require generation of an additional PDU including only the LI indicating that there is a tail (not including SDU data).

[0077] FIG. 10 is a diagram showing processing when the next PDU after reception of the current PDU is retransmitted in the embodiment of the present invention. This corresponds to Fig. 4, which shows the conventional processing. The RLC receiving side (receiving side wireless communication device) receives PDUs sequentially. The end of SDU # 1 is included in PDU # 3, and it is also indicated in PDU # 3 that the end of SDU # 1 matches the end of PDU # 3 by the processing of the embodiment of the present invention described above. Therefore, from the reception of PDU # 3, the end of SDU # 1 can be recognized and the completion of SDU # 1 can be confirmed. In other words, it is not affected by the delay in receiving the next PDU # 4 (such as when it is retransmitted), and can be transferred to the upper layer as soon as SDI is completed.

FIG. 11 is a diagram for explaining the delay of SDU transfer to higher layers according to the first example. The first example shows the case of forwarding according to the order of PDUs (sequence number order). A simple explanation will be given when one SDU is assembled by one PDU. The end of S DU # 1 is the end of PDU # 1, Fig. 11 (a) shows the delay when there is no retransmission, and Fig. 11 (b) shows the end of SDU # 1 is the end of PDU # 1. Figure 11 (c) shows the delay due to conventional processing when PDU # 2 including LI indicating the end is retransmitted.Figure 11 (c) shows PDU # including the LI indicating the end of PDU # 1. FIG. 5 is a diagram showing a delay due to processing in the embodiment of the present invention when 2 is retransmitted. When there is no retransmission, the time (delay time) from the start of reception of one PDU to the start of SDU transfer to the upper layer is set to 1.

As shown in FIG. 11 (a), when there is no retransmission, the delay time is the reference time “1” for all four PDUs, so the average delay time is “1”.

[0080] In Fig. 11 (b) showing the conventional case, when PDU # 2 is retransmitted and PDU # 2 retransmitted after PDU # 4 is received, the completion power of SDU # 1 Since it cannot be determined until PDU # 2 is received and cannot be transferred, the transfer of SDU # 1 is greatly delayed. When transferring SDUs in order, the transfer delay of SDU # 1 is affected and the transfer of subsequent SDUs is also greatly delayed. In the case of Fig. 11 (b), the average delay time is "5". .

[0081] On the other hand, in FIG. 11 (c) showing the case of the embodiment of the present invention, since information indicating the end of SDU # 1 is included in PDU # 1, SDU # 1 is a normal delay time. Transferred with `` 1 '' and SDU Only the SDUs after # 2 are delayed, and the average delay time in this case is “3.25”, which is significantly reduced compared to the case of Fig. 11 (b). In addition, the capacity of the notifier memory for holding data can be reduced.

FIG. 12 is a diagram for explaining the delay of SDU transfer to a higher layer than in the second example. The second example shows the case of transferring in the order of completion of SDUs in any order other than the order of SDUs. Similar to Fig. 11, the explanation is simplified when one SDU is assembled by one PDU. Also, the end of SDU # 1 is the end of PDU # 1, Fig. 12 (a) shows the delay when there is no retransmission, and Fig. 12 (b) shows the end of SDU # 1 is PDU # Figure 12 (c) shows the delay due to conventional processing when PDU # 2 including LI indicating the end of 1 is retransmitted.Figure 12 (c) shows the end of SDU # 1 with LI indicating the end of PDU # 1. FIG. 10 is a diagram showing a delay due to processing in the embodiment of the present invention when included PDU # 2 is retransmitted. When there is no retransmission, the time (delay time) from the start of reception of one PDU to the start of SDU transfer to higher layers is set to 1.

As shown in FIG. 12 (a), when there is no retransmission, the delay time is the reference time “1” for all four PDUs, so the average delay time is “1”.

[0084] In Fig. 12 (b) showing the conventional case, when PDU # 2 is retransmitted and PDU # 2 retransmitted after PDU # 4 is received, the completion power of SDU # 1 PDU # 2 SDU # 1 transfer is significantly delayed because it cannot be determined until it is received and cannot be transferred. SDU # 2 is also not assembled until it receives retransmitted PDU # 2. When SDU # 3 and # 4 are successfully received, they are transferred with a delay time of “1”, and then SDU # 1 and # 2 are transferred with a significant delay based on the reception of retransmitted PDU # 2. The In the case of Figure 12 (b), the average delay time is “3”.

[0085] On the other hand, in FIG. 12 (c) showing the case of the embodiment of the present invention, since information indicating the end of SDU # 1 is included in PDU # 1, SDU # 1 is a normal delay time. It is transferred with “1”, and SDU # 3 and # 4 are also transferred with normal delay time “1”, and only SDU # 2 is delayed. In this case, the average delay time is “1.75”, which is significantly reduced compared to the case of Fig. 12 (b). In addition, the capacity of the noffer memory for holding data can be reduced.

[0086] In the above description, the wireless communication device of the present invention is a radio communication protocol configuration. The communication processing in the case of converting from the SDU to the PDU has been described for the RLC layer belonging to the carrier 2, but this is not limited to the SDU and PDU in the RLC layer. It can be applied to communication processing when one data unit is divided or combined and converted to a second data unit.

Industrial applicability

The present invention can be applied to a radio communication terminal apparatus and a radio base station apparatus constituting a radio communication system such as W-CDMA.

Claims

The scope of the claims

[1] A predetermined layer that constitutes a protocol layer for wireless communication, receives a variable-length first data set, and converts one first data unit into one or a plurality of fixed-length second data units. In a wireless communication device that converts to

If the received data size of the first data unit is larger than the data size of the free data area of the second data unit, adjust the first data unit to the data size of the free data area of the second data unit. A dividing means for dividing the data into a plurality of segment data;

If the data size of the received first data unit or the last segment data of the plurality of segment data is one octet less than the data size of the free data area of the second data unit, the end of the first data unit Is set in the predetermined area of the header area of the second data unit to indicate that the last octet of the second data unit is one octet before and the last octet of the second data unit is padding. A wireless communication apparatus.

[2] In claim 1,

The wireless communication apparatus, wherein the predetermined area is a header extension area of a protocol data unit.

[3] A predetermined layer that constitutes a protocol layer for wireless communication, receives a variable-length first data set, and converts one first data unit into one or a plurality of fixed-length second data units. In a wireless communication device that converts to

The entire received first data unit or the end of the last segment data of the plurality of segment data is included in the empty data area of the second data unit, and the end position of the end is included in the header area of the second data unit. If an indicator is included

, The data stored in the remaining free space of the second data unit after the end A wireless communication apparatus comprising: a control unit that sets a remaining identifier indicating a type in a predetermined area of a header area of the second data unit.

[4] In claim 3,

The wireless communication apparatus, wherein the predetermined area in which the remaining identifier is set is a part of an area assigned to the indicator, and the position of the end can be indicated by the remaining area.

[5] In claim 4,

When the empty data area of the second data unit includes the entire first data unit or a plurality of the last segment data and includes an indicator indicating the end position of each, a part of the last indicator area And a remaining identifier indicating the type of data stored in the remaining free area of the second data unit.

[6] In claim 3,

The remaining identifier identifies the type of data stored in the remaining free space of the data unit 1S at least whether it is the entire first data unit, segment data of the first data unit, or padding data. Wireless communication device.

[7] In claim 3,

The remaining identifier is the type of data stored in the remaining free space of the data unit. At least the entire first data unit, the segment data of the first data unit, the padding data or the entire first data unit and the last octet. A wireless communication apparatus that identifies whether a padding combination is inserted.

[8] In any one of claims 1 to 7,

The first data unit is a service data unit (SDU) transmitted / received in an RLC layer belonging to Layer 2 constituting a protocol layer for wireless communication, and the second data unit is transmitted / received in the RLC layer. A wireless communication device characterized by being a protocol data unit (PDU).