KR101341752B1 - Method and apparatus for blind decoding in mobile communication system - Google Patents

Abstract

The present invention relates to blind decoding, and more particularly to a method and apparatus for efficiently signaling candidate packet sizes of blind decoding.

In a packet transmission method in a base station according to an embodiment of the present invention, in the method for transmitting a packet in a base station in a mobile communication system, the number of candidate packet sizes (Candidate Packet Size, CPS) to be decoded is determined, and the determined candidate packet size is determined. Signaling the number of packets to the terminal, determining a reference size for packets to be transmitted, and transmitting the reference size to the terminal through a semi-persistent transmission resource when the number of candidate packet sizes is varied. Include.

Long Term Evolution (LTE), Persistent Packet Size, Candidate Packet Size, Reference Size

Description

TECHNICAL AND METHOD AND APPARATUS FOR PROCESSING BLIND DECODING IN MOBILE COMMUNICATION SYSTEM

The present invention relates to a mobile communication system, and more particularly, to a method and apparatus for processing a blind decoding by a terminal and a base station.

3GPP is working on a specification for the next generation mobile communication system, Long Term Evolution (LTE). LTE is a technology that realizes high-speed packet-based communication with a transfer rate of up to 100 Mbps with commercialization target of about 2010. Various methods are discussed for this purpose. For example, there is a method of reducing the number of nodes located on a communication path by simplifying the structure of a network, and a method of approaching wireless protocols to a wireless channel as much as possible. In LTE, a scheduler located in a base station manages and allocates radio transmission resources, and the base station reports a buffer status from a terminal before allocating reverse radio transmission resources. In voice services such as Voice over Internet Protocol (VoIP), where small packets occur periodically, the amount of reverse data is reported and allocated for each reverse packet transmission, or the forwarded resource is allocated for each forward packet transmission. This is a factor that hinders communication efficiency. As a solution to this problem, the allocation of semi-persistent transmission resources that allow the terminal to continuously use until once allocated transmission resources are released. By using the semi-persistent transmission resource, it is not necessary to request a transmission resource or to allocate a transmission resource every time a packet is transmitted, thereby using the transmission resource more efficiently.

In the LTE communication system, the base station indicates not only the transmission resource but also the size of a packet to be transmitted using the transmission resource, and thus, the base station allocates a semi-persistent transmission resource to the terminal. The transmission resources are used to signal the size of packets to be transmitted or received. For convenience of explanation, the size of a packet to be transmitted or received by the semi-persistent transmission resource is hereinafter referred to as a 'persistent packet size'.

The packet size generated in the VoIP has some variation. Whenever the packet size changes, changing the semi-persistent packet size reduces the utility of the semi-permanent transmission resources. Therefore, a method of defining several semi-persistent packet sizes corresponding to the semi-persistent transmission resources and performing blind decoding is under discussion.

1 is a diagram illustrating a process of applying blind decoding to a packet received through a conventional semi-persistent transmission resource.

Before performing the communication using the semi-permanent transmission resource in the mobile communication system composed of the transmitting device 105 and the receiving device 110, the transmitting device 105 and the receiving device 110 are connected to the semi-persistent transmission resource and the semi-permanent packet size in step 115. To agree. In the case of using the blind decoding, a plurality of packet sizes, for example, PPS1, PPS2, and PPS3 may be agreed as the semi-persistent packet size.

The transmitting apparatus 110 that has agreed on the semi-persistent transmission resource and the semi-persistent packet size selects one of PPS1, PPS2, and PPS3, for example, reference numeral 120, and configures a packet having the selected PPS2 size. In step 125, the transmitting device 110 transmits the configured packet to the receiving device 105 through the semi-persistent transmission resource. The reception device 105 sequentially applies semi-permanent packet sizes PPS1, PPS2, and PPS3 until the packet is successfully decoded in decoding the packet received through the semi-persistent transmission resource in step 130.

The semi-persistent transmission resource should be changed in various situations such as the channel status of the terminal, the call status, the codec, etc., and the allocation or change of the semi-persistent transmission resource using a higher layer control message is a new transmission. There is a problem that a long delay occurs until the resource is applied. Therefore, it is more preferable to allocate or change the semi-persistent transmission resource using the L1 / L2 control channel rather than using the upper layer control message.

As described above, when the semi-persistent transmission resource and the blind decoding are combined, the transmitter and the receiver should signal not only the semi-persistent transmission resource but also information on a plurality of semi-persistent packet sizes. Since the upper layer control message can be flexibly adjusted in size, it is possible to convey information about the plurality of semi-persistent packet sizes through the upper layer control message. However, if it is necessary to use a physical layer control channel called an L1 / L2 control channel in transmitting information about the semi-persistent packet sizes, it is impossible to signal the plurality of semi-permanent packet sizes.

Accordingly, there is a need for a method capable of signaling a semi-persistent packet size to be used for blind decoding using the L1 / L2 control channel.

Accordingly, the present invention, which was devised to solve the problems of the prior art operating as described above, provides a method and apparatus capable of signaling a semi-permanent packet size to be used for blind decoding using an L1 / L2 control channel.

The present invention also provides a method and apparatus for enabling blind decoding without signaling all packet sizes used for blind decoding.

In addition, the present invention changes the size of n candidate packets by signaling only the reference size, and allocates semi-persistent transmission resources by signaling a semi-persistent transmission resource and a reference size for deriving the candidate packet size through the control channel of the physical layer. It provides a method and apparatus that can use a more efficient physical layer control channel.

In a packet transmission method in a base station according to an embodiment of the present invention, in the method for transmitting a packet in a base station in a mobile communication system, the number of candidate packet sizes (Candidate Packet Size, CPS) to be decoded is determined, and the determined candidate packet size is determined. Signaling the number of packets to the terminal, determining a reference size for packets to be transmitted, and transmitting the reference size to the terminal through a semi-persistent transmission resource when the number of candidate packet sizes is varied. Include.
In a packet receiving method in a terminal according to an embodiment of the present invention, in the packet receiving method in a terminal in a mobile communication system, receiving a number of candidate packet sizes (CPS) to be decoded from a base station; When the number of candidate packet sizes is varied, receiving a reference size from the base station, calculating candidate packet sizes using the number of candidate packet sizes to be decoded and the reference size, and the candidate packet size And sequentially decoding the received packets using the network.
An apparatus for transmitting a packet in a base station according to an embodiment of the present invention may include a packet size number determination unit for determining a number of candidate packet sizes (CPSs) to be decoded in a packet transmission apparatus in a base station in a mobile communication system. When the number of candidate packet sizes is varied, a reference size determiner for determining a reference size for packets to be transmitted, and the number of the determined candidate packet sizes are signaled to the terminal, and the reference size is applied to the semi-persistent transmission resource. It includes a transmitter for transmitting to the terminal through.
An apparatus for receiving a packet in a base station according to an embodiment of the present invention, in the apparatus for receiving a packet in a terminal in a mobile communication system, receives a number of candidate packet sizes (CPSs) to be decoded from the base station, and receives the candidate. When the number of packet sizes is variable, a receiver for receiving a reference size from the base station, a control unit for calculating candidate packet sizes using the number of candidate packet sizes to be decoded and the reference size, and using the candidate packet sizes And a decoder to sequentially decode the received packets.

The present invention can change the size of n candidate packets by signaling only the reference size.

In addition, the present invention can use a more efficient physical layer control channel in allocating the semi-persistent transmission resources by signaling the semi-persistent transmission resources and the reference size to derive the candidate packet size through the control channel of the physical layer.

The present invention can also signal a semi-permanent packet size to be used for blind decoding using the L1 / L2 control channel.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention, and may be changed according to the intentions or customs of the user, the operator, and the like. Therefore, the definition should be based on the contents throughout this specification.

The present invention provides a method and apparatus for enabling blind decoding without signaling all packet sizes used for blind decoding. In more detail, the transmitting apparatus and the receiving apparatus recognize information that can derive the first packet size and the second packet size from the reference packet size and the reference packet size, and the reference packet size, the first packet size, The blind decoding is performed using the second packet size. When the base station allocates a semi-persistent transmission resource, the base station signals the reference packet size together, and the terminal and the base station that have acquired the information capable of deriving the first packet size and the second packet size in a call setup process, etc. Derive the packet sizes to blind decode from. If there is a need to change the packet sizes to be blind-decoded afterwards, the base station signals only the new reference packet size, and the terminal and the base station signal the remaining packet size from the packet size derivation information acquired in the new reference packet size and call setup process. Induce them.

The packet size generated in VoIP varies depending on the codec mode or the type or configuration of the header compression protocol.

2 is a diagram illustrating a structure of a VoIP packet to which the present invention is applied.

As illustrated in FIG. 2, the VoIP packet transmitted / received through the semi-persistent transmission resource may include a two-layer header (L2 header) 205, a compressed IP / UDP / RTP header 210, and a VoIP frame ( frame) 215. The two-layer header is a sum of headers inserted by a layer device classified into a two-layer protocol such as RLC (Radio Link Control) and MAC (Medium Access Control), and usually has a constant value.

Since the uncompressed IP / UDP / RTP header 210 has a size of 40 bytes or 60 bytes and the VoIP frame 215 is only a few tens of bytes, transmitting the header as it is is inefficient in terms of overhead. . Therefore, LTE reduces the IP / UDP / RTP header by several bytes using a technique called RObust Header Compression (ROHC). In order to compress the header, the receiving device must successfully receive the IP / UDP / RTP pool header one or more times, and only information changed from the pool header is transmitted and received after the pool header is successfully transmitted and received. Depending on the type or amount of changed information, the compressed header has a value between 3 and 60 bytes.

The VoIP frame 215 stores actual voice data and has a predetermined size depending on the type or mode of the codec used. For example, an adaptive multi rate (AMR) codec commonly used in 3GPP generates VoIP frames of 32 bytes in 12.2 kbps mode and 14 bytes in 4.75 kbps mode.

In summary, the size of the VoIP packet transmitted and received through the semi-persistent transmission resource is shown in Table 1 below.

In Table 1, H ₁ , H ₂ , and H ₃ are as follows.

⊙ H ₁ : Constant as the sum of L2 overhead.

H ₂ : When compressing an IP / UDP / RTP header using the ROHC protocol, the amount of overhead added according to the size and value of the CID (Context Identifier) is 0, 1 or 2 bytes. It maintains a constant value within one session and it is not known which value of the set will be applied until the header compression device processes the first packet.

⊙ H ₃ : When compressing the IP / UDP / RTP header using the ROHC protocol, the size of the remaining header except for the part including the CID. The value varies between 2 and 63 bytes depending on the amount or type of new information included in the header being compressed. For the convenience of description and is termed the minimum value of the maximum value of H ₃ H _3MIN, H ₃ to H _3MAX.

Since the size of the L2 overhead and the size of the VoIP frame are constant, the size of the VoIP packet is determined according to the compression header size unless the codec mode of the VoIP is changed. And variations of the VoIP packet size H _3MIN ~ H _3MAX Constant in bytes For example, the size of the VoIP packet from the 12.2 kbps codec mode has a value between _{[H 1 + H 2 + H} 3MIN + 32] and byte _{[H 1 + H 2 + H} 3MAX + 32] byte.

Changing the codec mode only changes the size of the VoIP frame and does not affect the size or variation of the remaining components. Variation over VoIP packet size in the present invention, the codec mode is left intact H _3MIN ~ H _3MAX in view from that point event to the bytes defining candidate packet size of the blind decoding to efficiently cope with the variation, and the blind decoding One of the sizes of candidate packets is defined as a reference packet size. In addition, the difference between the reference packet size and the remaining candidate packet sizes is signaled to the transmitting device and the receiving device in advance in the call setup process. Even if candidate packet sizes need to be newly set due to a change in the codec mode, the base station is associated with a transmitting apparatus because the same relationship exists as the signal signaled in the call setup process between the new candidate packet sizes and the new reference packet size. Only the new reference packet sizes corresponding to the new candidate packet sizes are signaled to the receiving device, and the transmitting device and the receiving device derive the new candidate packet sizes by themselves. As described above, since the present invention achieves the same effect as signaling only one reference packet size to signal n candidate packet sizes, the reference packet size to be used for blind decoding through the L1 / L2 control channel is semi-permanent. Transmission resources can be signaled together.

3 is a flowchart illustrating a forward operation according to an embodiment of the present invention.

In the call establishment process, the base station 310 determines d ₁ , d ₂ ,..., D _{n - 1} , which are the difference between the reference size and the semi-permanent packet sizes, in step 315, and signals the terminal 305 in step 317. . The d ₁ , d ₂ ,..., And d _{n - 1} are used to calculate candidate packet sizes from future reference sizes. The process of determining the base station d ₁ , d ₂ , ..., d _{n -1} is as follows.

The base station 310 judges _3MIN H and H _3MAX in consideration of the nature of the arc is first set. H _3MAX for IPv4 _calls is about 43 bytes, and H _3MAX for IPv6 _calls is about 63 bytes. H _3MIN for IPv4 calls is 0 bytes or 2 bytes, and H _3MIN for IPv6 calls is 2 bytes. The base station 310 determines the H and H _{3MIN 3MAX} determines the number n of the blind decoding candidate packet size (Candidate Packet Size, CPS). As the number of candidate packet sizes increases, more processing load is added to the terminal 305 so that the base station 310 determines n in consideration of the processing capability of the terminal 305. Considering that the smallest packet occurs most frequently, and packets that are larger than a few bytes sometimes occur, n is set to 3 so that the candidate packet sizes include the minimum size, the size of a few bytes more than the minimum size, and the maximum size. Can be set. When the base station 310 determines the n, the n H ₃ values are appropriately determined by referring to the generation pattern of the packet size. As in the above example, you can define the H ₃ and so on corresponding to the largest size in case the H _3, and if the case of the H _3, be greater than the minimum packet size corresponding to a minimum packet size of bytes corresponding to the largest packet size. For convenience, the following description of the determined n H ₃ the size of the order of H _{3 _1, _2} H _3, ..., is named as H _{3 _n.} H _{3 _1} is the smallest H ₃ , H _{3 _ n} is the largest H ₃ .

The base station 310 using the H _{3 _1} , H _{3 _2} , ..., H ₃ _ _n in step 315 as shown in Equation 1 below, d ₁ , d ₂ , ..., d _{n -1} Determine.

d ₁ = H _{3 _2} -H _{3 _1,}

d ₂ = H _{3 _3} -H _{3 _1} ,

...,

d _{n -1} = H _{3 _n} -H _{3 _1}

After signaling the determined d ₁ , d ₂ ,..., And d _{n − 1} to the terminal 305, the base station 310 waits until a VoIP packet to be transmitted to the terminal 305 arrives.

When the first forward VoIP packet to be transmitted to the terminal 305 arrives, the base station 310 compresses the header of the packet and determines a reference size in step 320. The reference size corresponds to the smallest of the candidate packet sizes of the blind decoding, and is a sum of H ₁ , H ₂ , and H _{3 _1 plus} the VoIP frame size of the corresponding codec mode. H _{3 _1} is the smallest value of H ₃ selected by the base station 310, and is generally the same as H _3MIN . As described above, H ₂ has one of 0 bytes, 1 byte, and 2 bytes, and may determine the value after performing compression on the first packet. The base station 310 selects the candidate packet sizes of blind decoding CPS ₁ , CPS ₂ , ..., CPS _n using the reference size determined in step 325 and d ₁ , d ₂ ,..., And d _{n - 1} . It is calculated as in <Equation 2>.

CPS ₁ = reference size,

CPS ₂ = reference size + d ₁ ,

CPS ₃ = reference size + d ₂ ,

CPS ₄ = reference size + d ₃ ,

...,

CPS _n = reference size + d _{n -1}

The base station 310, CPS ₁ , CPS ₂ , ..., CPS _n in step 330 The candidate packet size for transmitting the VoIP packet most efficiently is determined, and the base station 310 transmits the first packet through the semi-persistent transmission resource in step 335 and the semi-persistent transmission resource and the reference through the L1 / L2 control channel. Signal size. In step 340, the base station 310 constructs a MAC PDU multiplexed with VoIP packets using the determined candidate packet size and transmits it through a semi-persistent transmission resource. The semi-persistent transmission resource and the reference size are signaled only once, and the terminal 305 and the base station 310 transmit and receive subsequent VoIP packets using the semi-persistent transmission resource and the reference size without transmitting additional L1 / L2 control information in the future. . The terminal 305 when recognizing the size of the reference, at step 345 by summing to the _{d 1, d 2, ...,} d n -1 to the standard size as shown in <Formula 3>, which are packet size candidates CPS ₁ , CPS ₂ , ..., CPS _n are calculated.

CPS ₁ = reference size,

CPS ₂ = reference size + d ₁ ,

CPS ₃ = reference size + d ₂ ,

CPS ₄ = reference size + d ₃ ,

...,

CPS _n = reference size + d _{n -1}

In operation 350, the terminal 305 determines that the packet size received through the semi-persistent transmission resource is one of the candidate packet sizes, and performs blind decoding. That is, the terminal 305 attempts decoding by sequentially applying the candidate packet sizes until the packet received through the semi-persistent transmission resource is successfully decoded.

The base station 310 does not change the reference size until an event in which the size pattern of the VoIP packet changes, such as a change in the forward codec mode or a call state, occurs, and the terminal 305 does not change the reference size. If not, blind decoding is performed on the VoIP packet using existing candidate packet sizes. If the size pattern of the VoIP packet is changed, the base station 310 applies new candidate packet sizes by calculating a new reference size and signaling it to the terminal 305. That is, signaling a new reference size to the terminal 305 has the same effect as signaling n new candidate packet sizes. Instead of using d ₁ , d ₂ , ..., d _{n -1} , the base station 310 notifies the terminal 305 in the call setup process by tabulating the relationship between the reference size for each codec mode and the candidate packet sizes. You may. For example, if there is a need to use the candidate packet sizes by pre _- signing n-1 candidate packet sizes such as CPS_ _1x , CPS_ _2x , CPS_ _3x , and CPS_ _{(n-1) x} for any reference size x, The reference size x is reported via the L1 / L2 control channel. When the reference size x is signaled, the terminal 305 receives the candidate packet sizes CPS_ _1x , CPS_ _2x , CPS_ _3x ,..., CPS_ _{(n-1) x} that are candidate packet sizes associated with the reference size x and the reference size x. It considers the size and performs blind decoding.

4 is a flowchart illustrating an operation of a terminal receiving a packet through a forward semi-persistent transmission resource according to an embodiment of the present invention.

Referring to FIG. 4, in step 405, the terminal 305 receives d ₁ , d ₂ ,..., D _{n −1} from the base station 310 through a call setup process. Alternatively, mapping information (tabled mapping information) listing mapping relationships between the reference size and the candidate packet sizes may be signaled. For example, the base station 310 determines n ₁ reference sizes in advance, associates the reference sizes with the required number of candidate packet sizes, and sets up a call setting information indicating a mapping relationship between the reference sizes and the candidate packet sizes. Signaling to the terminal 305 in the process.

After completing the call setup process, the terminal 305 recognizes the reference size through the L1 / L2 control channel or another predetermined control channel in step 410. In the above process, the terminal 305 may also acquire semi-persistent transmission resource information. In step 415, the terminal 305 calculates candidate packet sizes CPS ₁ , CPS ₂ , ..., CPS _n using Equation 3 using the reference size.

In step 405, if the mapping table storing the mapping relationship between the reference size and the candidate packet sizes is signaled, the terminal 305 detects the reference size from the mapping table and recognizes the mapped candidate packet sizes in step 415.

In step 420, upon receiving the packet through the semi-persistent transmission resource, the terminal 305 performs blind decoding using the CPS ₁ , CPS ₂ , ..., CPS _n as candidate packet sizes. That is, one of the candidate packet sizes is regarded as the size of the received packet and attempts to decode until the packet received through the semi-persistent transmission resource is successfully decoded. If the initially selected candidate packet size is the size of the actual packet, the terminal 305 may succeed in decoding at the first attempt. If the m-th candidate packet size selected by the terminal 305 is the size of the actual packet, the terminal 305 may attempt decoding at least m times and then succeed in decoding.

The terminal 305 receives the packet through the semi-persistent transmission resources, and also monitors whether the reference size changes in step 425. That is, a new reference size is signaled through a control channel, and when a new reference size is signaled, the process returns to step 410 to calculate new candidate packet sizes from the new reference size, and then blind decoding using the new candidate packet sizes. Resume the operation to perform. However, if the reference size does not change, the process returns to step 420 to perform blind decoding using existing candidate packet sizes.

5 is a flowchart illustrating the overall operation in the reverse direction according to an embodiment of the present invention.

In the forward operation, the terminal plays the role of the receiving device. In the reverse operation, the terminal plays the role of the transmitting device.

In step 515, the base station 510 determines u ₁ , u ₂ ,..., U _{n- 1} , which are the difference between the reference size and the semi-permanent packet sizes, and signals the terminal 505. The process of the base station 510 is determining the value is the same as the procedure for determining the _{d 1, d 2, ...,} d n -1 detailed description thereof will be omitted.

When the base station 505 receives the first reverse VoIP packet from the terminal 505, the base station 505 determines a reference size from the size of the packet in step 520. The reference size corresponds to the smallest of the candidate packet sizes of the blind decoding, and is a sum of H ₁ , H ₂ , and H _{3 _1 plus} the VoIP frame size of the corresponding codec mode. H _{3 _1} is the smallest value of H ₃ selected by the base station 50, and is generally the same as H _3MIN .

In step 525, the base station 505 notifies the terminal 505 of the reference size through a predetermined control channel. In this case, the UE may also allocate reverse semi-persistent transmission resources to be used for reverse VoIP packet transmission.

When the terminal 505 recognizes the reference size, in step 530, u ₁ , u ₂ ,..., U _n−1 are added to the reference size and candidate packet sizes CPS ₁ , CPS ₂ , ..., CPS _n is calculated as shown in Equation 4 below.

CPS ₁ = reference size,

CPS ₂ = reference size + u ₁ ,

CPS ₃ = reference size + u ₂ ,

CPS ₄ = reference size + u ₃ ,

...,

CPS _n = reference size + u _n-1

The base station 510 also signals the reference size to the terminal 505 in step 535, and then calculates the candidate packet sizes CPS ₁ , CPS ₂ ,..., CPS _n .

When the VoIP packet arrives from the upper layer, the terminal 505 compresses the header of the packet and attaches a predetermined second layer header or the like. Hereinafter, for convenience of description, a packet attached with a layer 2 header and transmitted through a wireless channel will be referred to as a MAC medium access control protocol data unit (MAP PDU). In step 540, the terminal 505 transmits the MAC PDU using the semi-persistent transmission resources. First, the terminal 505 determines the packet size to most efficiently transmit the MAC PDU. In short, the terminal 505 selects a candidate packet size having a size closest to the MAC PDU size among the candidate packet sizes larger than the MAC PDU as the packet size of the MAC PDU. The difference between the size of the MAC PDU and the selected packet size is then corrected by inserting padding in the MAC PDU or multiplexing other user data. In other words, the terminal 505 selects the packet size to which the data other than the padding or the VoIP packet is multiplexed the smallest in transmitting the packet through the semi-persistent transmission resource, and multiplexes the MAC PDU by padding or other data. The size of is adjusted to fit the size of the selected packet. If there is no candidate packet size larger than the MAC PDU, the terminal 505 selects the largest candidate packet size.

In step 545, the terminal 505 transmits the VoIP packet to the base station 510 using the selected packet size and semi-persistent transmission resources. The base station 510 performs blind decoding by considering the size of a packet received through the semi-persistent transmission resource as one of CPS ₁ , CPS ₂ ,..., And CPS _n in step 550. The base station 510 does not change the reference size until an event in which the size pattern of the VoIP packet is changed, such as a reverse codec mode change or a call state change, does not change the reference size. If not, the VoIP packet is transmitted using existing candidate packet sizes.

When the size pattern of the VoIP packet is changed, the base station 510 calculates a new reference size and signals it to the terminal 505. The terminal 505 and the base station 510 calculate new candidate packet sizes from the reference size, and perform blind decoding using the new candidate packet sizes in the future.

Instead of signaling the difference value between the reference size and candidate packet sizes such as u ₁ , u ₂ ,..., And _{n n-1} , the relationship between the reference size for each codec mode and the candidate packet sizes is tabled. The base station may notify the terminal in the setting process. For example, n-1 candidate packet sizes such as CPS_ _1x , CPS_ _2x , CPS_ _3x , and CPS_ _{(n-1) x} are previously signaled to the terminal 505 for an arbitrary reference size x, and the candidate packet size If there is a need to use them, the terminal 505 is notified of the reference size x through the L1 / L2 control channel. When the reference size x is signaled, the terminal 505 uses the candidate packet sizes associated with the reference size x and the reference size x as CPS_ _1x , CPS_ _2x , CPS_ ₂₃ , and CPS_ _{(n-1) x} as candidate packet sizes. Perform blind decoding.

6 is a flowchart illustrating an operation of a terminal for transmitting a packet received through a reverse semi-persistent transmission resource according to an embodiment of the present invention.

In step 605, the terminal 505 receives u ₁ , u ₂ ,..., U _n-1 from the base station 510 through a call setup process. In operation 605, a mapping relationship between the reference size and the candidate packet sizes may be signaled. The information indicating the mapping relationship may be configured in the form of a mapping table listing the relationship between the reference sizes and the related candidate packet sizes. After completing the call setup process, the terminal 505 recognizes the reference size information through the L1 / L2 control channel or another predetermined control channel in step 610. In the above process, the terminal 505 may also recognize semi-persistent transmission resource information. In step 615, the terminal 505 derives candidate packet sizes CPS ₁ , CPS ₂ , ..., CPS _n from the reference size information. If u ₁ , u ₂ ,..., U _{n − 1} are signaled in step 605, the terminal 505 calculates CPS ₁ , CPS ₂ , ..., CPS _n as shown in Equation 4 above. do.

If a mapping table of reference size and candidate packet sizes is signaled in step 605, the terminal 505 retrieves the corresponding reference size from the mapping table in step 615 and recognizes relevant candidate packet sizes from the searched reference size. . In step 620, the terminal 505 determines the size of the MAC PDU to be transmitted through the semi-persistent transmission resources. When the VoIP packet to be transmitted through the semi-persistent transmission resource is compressed and a size obtained by summing a predetermined L2 header is x, the terminal 505 is the candidate closest to x among candidate packet sizes equal to or larger than x. The packet size is selected as the size of the MAC PDU to be transmitted. The terminal 505 stores the VoIP packet in the MAC PDU of the selected size, and if extra space is left, other data is stored or padding is inserted in the space.

If there is no size of the candidate packet meeting the criteria, that is, if the size of the sum of the predetermined headers to the VoIP packet is larger than the size of the largest candidate packet, the terminal 505 selects the largest candidate packet size. In this case, VoIP packets are stored in MAC PDUs.

When the terminal 505 determines the size of a packet to be transmitted using the uplink transmission resource, the terminal 505 configures a MAC PDU of the size and transmits it through the uplink semi-persistent transmission resource.

The terminal 505 transmits a packet through a semi-persistent transmission resource, and monitors whether the reference size changes in step 625. That is, the control channel monitors whether a new reference size is signaled. If the new reference size is signaled, the terminal 505 returns to step 610 to calculate new candidate packet sizes from the new reference size, and then configures and transmits a MAC PDU using one of the new candidate packet sizes. Resume the operation.

However, if the reference size does not change, the terminal 505 returns to step 620 to continue configuring and transmitting the MAC PDU using existing candidate packet sizes.

7 is a block diagram of a terminal according to an embodiment of the present invention.

The terminal is composed of a higher layer control device (not shown), a multiplexing and demultiplexing unit 705, a HARQ processing unit 710, a control unit 715, a control channel processing unit 720, and a transceiver unit 725.

The control unit 715 is d ₁ , d ₂ ,..., D _{n - 1} and u ₁ , u _{2 ,.} Receive ₁ The reference size is received from the control channel processor 720 to calculate forward candidate packet sizes and reverse candidate packet sizes. The controller 715 notifies the transceiver 725 of the forward candidate packet sizes and the semi-persistent transmission resource, and the candidate for the packet received through the semi-persistent transmission resource by the receiver of the transceiver 725. Blind decoding by applying the packet size. The control unit 715 also notifies the multiplexer and demultiplexer 705 of the reverse candidate packet sizes, and the multiplexer and demultiplexer 705 receives a MAC PDU multiplexed with VoIP packets according to the reverse candidate packet size. Configure.

The transceiver 725 of the terminal transmits and receives a packet through a wireless channel or transmits and receives control information.

The HARQ processing unit 710 transmits the packet received from the multiplexing and demultiplexing unit 705 to the base station via the transceiver unit 725 through a predetermined HARQ operation. The HARQ processor 710 is a set of soft buffers configured to perform an HARQ operation and is identified by a HARQ process identifier. The control channel processor 720 monitors a control channel received by the transceiver 725, for example, a channel provided with reverse transmission resource allocation information, and processes control information received or transmits control information to be transmitted through the transmitter. Process. When semi-persistent transmission resource information and reference size information are received through the control channel, the control channel processor 720 transmits the information to the controller 715.

8 is a block diagram of a base station according to an embodiment of the present invention.

The base station is composed of a higher layer control device (not shown), a multiplexing and demultiplexing unit 805, a HARQ processing unit 810, a control unit 815, a control channel processing unit 820, and a transceiver unit 825.

The control unit 815 is d ₁ , d ₂ ,..., D _{n - 1} and u ₁ , u _{2 ,.} Receive ₁ In addition, the controller 815 receives a reference size from the upper layer control device. The controller 815 transmits the reference size to the control channel processor 820 so that the reference size is signaled through a predetermined control channel. The controller 815 notifies the transceiver unit 825 of the reverse candidate packet sizes and the semi-persistent transmission resource, and the transceiver 825 receives the candidate packet size for the packet received through the semi-persistent transmission resource. Apply blind decoding. The control unit 815 also notifies the multiplexing and demultiplexing unit 805 of the forward candidate packet sizes, and the multiplexing and demultiplexing unit 805 is configured to generate a MAC PDU multiplexed with VoIP packets according to the forward candidate packet size. Configure. The transceiver 825 of the base station transmits and receives a packet or transmits and receives control information through a wireless channel.

The HARQ processing unit 810 transmits the packet received from the multiplexing and demultiplexing unit 805 to the terminal via the transceiver unit 825 through a predetermined HARQ operation. The HARQ processor 810 is a set of soft buffers configured to perform an HARQ operation and is identified by a HARQ process identifier. The control channel processor 820 transmits predetermined control information through a predetermined control channel. For example, it transmits scheduling information through an L1 / L2 control channel.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the present invention.

1 is a flowchart illustrating a process of applying blind decoding to a packet received through a conventional semi-persistent transmission resource;

2 is a diagram illustrating a structure of a VoIP packet to which the present invention is applied;

3 is a flowchart illustrating a forward operation according to an embodiment of the present invention;

4 is a diagram illustrating a forward operation of a terminal receiving a packet through a forward semi-persistent transmission resource according to an embodiment of the present invention;

5 is a flowchart illustrating a reverse operation according to an embodiment of the present invention;

6 is a flowchart illustrating a reverse operation of a terminal transmitting a packet received through a reverse semi-persistent transmission resource according to an embodiment of the present invention;

7 is a block diagram of a terminal device according to an embodiment of the present invention;

8 is a block diagram of a base station apparatus according to an embodiment of the present invention.

Claims (16)

In the packet transmission method in a base station in a mobile communication system, Determining the number of candidate packet sizes (CPSs) to be decoded and signaling the determined number of candidate packet sizes to the terminal; Determining a reference size for packets to be transmitted when the number of candidate packet sizes is varied; And transmitting the reference size to the terminal through a semi-persistent transmission resource. In a packet receiving method in a terminal in a mobile communication system, Receiving a number of candidate packet sizes (CPSs) to be decoded from a base station; Receiving a reference size from the base station when the number of candidate packet sizes varies; Calculating candidate packet sizes using the number of candidate packet sizes to be decoded and the reference size; And sequentially decoding the received packet by using the candidate packet sizes. A packet transmission apparatus in a base station in a mobile communication system, A packet size number determination unit for determining the number of candidate packet sizes (CPSs) to be decoded; A reference size determiner which determines a reference size for packets to be transmitted when the number of candidate packet sizes is varied; And a transmitter for signaling the determined number of candidate packet sizes to a terminal and transmitting the reference size to the terminal through a semi-persistent transmission resource. In a packet receiving apparatus in a terminal in a mobile communication system, A receiving unit receiving a number of candidate packet sizes (CPSs) to be decoded from a base station and receiving a reference size from the base station when the number of candidate packet sizes is varied; A controller configured to calculate candidate packet sizes using the number of candidate packet sizes to be decoded and the reference size; And a decoder for sequentially decoding the received packet using the candidate packet sizes. The method of claim 1, And the reference size is determined to be the smallest of the candidate packet sizes. The method of claim 1, In the base station in the mobile communication system, before the variable number of candidate packet sizes, the method comprising the step of transmitting a table of the relationship between the reference size for each codec mode and the candidate packet size to the terminal; Packet transmission method. The method of claim 1, And transmitting a difference value between the reference size and the remaining candidate packet sizes to the terminal before varying the number of candidate packet sizes. 3. The method of claim 2, Wherein the reference size is determined to be the smallest of the candidate packet sizes. 3. The method of claim 2, In the terminal in the mobile communication system, before receiving the variable number of candidate packet sizes, receiving a table of the relationship between the reference size for each codec mode and the candidate packet size from the base station Packet reception method. 3. The method of claim 2, And receiving a difference value between the reference size and the remaining candidate packet sizes from the base station before varying the number of candidate packet sizes. The method of claim 3, And the reference size is determined to be the smallest of the candidate packet sizes. The method of claim 3, In the base station in the mobile communication system before the variable number of the candidate packet size, further comprising a transmission unit for transmitting to the terminal a table of the relationship between the reference size for each codec mode and the candidate packet size Packet transmitter. The method of claim 3, And a transmitter configured to transmit a difference value between the reference size and the remaining candidate packet sizes to the terminal before varying the number of candidate packet sizes. 5. The method of claim 4, And the reference size is determined to be the smallest of the candidate packet sizes. 5. The method of claim 4, In the terminal in the mobile communication system, before receiving the variable number of the candidate packet size, further comprising a receiving unit for receiving a table of the relationship between the reference size for each codec mode and the candidate packet size from the base station Packet receiving device. 5. The method of claim 4, And a receiving unit for receiving a difference value between the reference size and the remaining candidate packet sizes from the base station before varying the number of candidate packet sizes.

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