KR20090080915A - Method of encoding data unit using different crc algorithms - Google Patents

Abstract

A method for encoding a data unit using a plurality of CRC(Cyclic Redundancy Check) algorithms is provided to reduce overheads of MAC PDU(Medium Access Control Protocol Data Unit) included in RACH(Random Access Channel) MSG 3 and to enhance data transmission efficiency by applying different CRC algorithms according to kinds of data included in the RACH MSG 3. A data receiving process is performed to receive one or more data from an upper layer. An error-checking function selection process is performed to select one error-checking function from the error-checking functions. The error-checking functions are composed by using the received data. A data process is performed to process the received data by using the selected error-checking function. A data transmission process is performed to transmit the processed data. The upper layer is a MAC(Medium Access Control) layer or a RLC(Radio Link Control) layer.

Description

How to encrypt a data unit using a plurality of RC algorithms {METHOD OF ENCODING DATA UNIT USING DIFFERENT CRC ALGORITHMS}

The present invention relates to a wireless communication system and a terminal for providing a wireless communication service, and to a base station in an Evolved Universal Mobile Telecommunications System (E-UMTS) or a Long Term Evolution System (LTE), which has been evolved from a Universal Mobile Telecommunications System (UMTS). The present invention relates to a method for transmitting and receiving data, and in particular, when a UE transmits a RACH message 3 (MSG 3) to a base station, different cyclic redundancy checks according to types of data included in the RACH MSG 3: The present invention relates to a method of transmitting RACH MSG 3 by applying a CRC algorithm to reduce overhead of a MAC PDU (Medium Access Control Protocol Data Unit) included in RACH MSG 3 to increase data transmission efficiency.

1 is a diagram illustrating a network structure of an Evolved Universal Mobile Telecommunications System (E-UMTS), which is a mobile communication system to which the present invention and the present invention are applied.

The E-UMTS system is an evolution from the existing UMTS system and is currently undergoing basic standardization in 3GPP. The E-UMTS system may be referred to as a Long Term Evolution (LTE) system.

E-UMTS networks can be largely divided into E-UTRAN and CN. The E-UTRAN is a UE (hereinafter abbreviated as UE) and a base station (hereinafter abbreviated as eNode B), a serving gateway (abbreviated as S-GW) located at the end of the network and connected to an external network. It consists of a Mobility Management Entity (hereinafter referred to as MME) that manages the mobility of. One or more cells may exist in one eNode B.

2 and 3 illustrate a structure of a radio interface protocol between a terminal and a base station based on the 3GPP radio access network standard. The wireless interface protocol consists of a physical layer, a data link layer, and a network layer horizontally, and vertically a user plane and control for data information transmission. It is divided into a control plane for signal transmission. The protocol layers are based on the lower three layers of the Open System Interconnection (OSI) reference model, which are well known in communication systems. L1 (Layer 1), L2 (Layer 2), and L3 (Layer 3) It can be divided into.

Hereinafter, each layer of the wireless protocol control plane of FIG. 2 and the wireless protocol user plane of FIG. 3 will be described.

The physical layer, which is the first layer, provides an information transfer service to an upper layer by using a physical channel. The physical layer is connected to the upper medium access control layer through a transport channel, and data between the medium access control layer and the physical layer moves through the transport channel. Then, data is moved between different physical layers, that is, between physical layers of a transmitting side and a receiving side through physical channels.

Medium access control (hereinafter referred to as MAC) of the second layer provides a service to a radio link control layer, which is a higher layer, through a logical channel. The radio link control layer (hereinafter referred to as RLC) layer of the second layer supports reliable data transmission. The PDCP layer of the second layer is a header compression that reduces the IP packet header size, which is relatively large and contains unnecessary control information, for efficient transmission in a low bandwidth wireless section when transmitting an IP packet such as IPv4 or IPv6. Compression) function. The PDCP layer is also used to perform encryption of C-plane data, for example RRC messages. PDCP also performs encryption of U-plane data.

The radio resource control layer (hereinafter abbreviated as RRC) layer located at the bottom of the third layer is defined only in the control plane, and the configuration and resetting of radio bearers (abbreviated as RB) are performed. It is responsible for the control of logical channels, transport channels and physical channels in relation to configuration and release. In this case, RB means a service provided by the second layer for data transmission between the terminal and the E-UTRAN.

The following is a detailed description of the RACH (Random Access Channel). The RACH channel is used for transmitting a short length of data upward. In particular, the RACH channel is used when there is a signaling message or user data to be transmitted upward by a terminal that has not been allocated a dedicated radio resource. Or, it may be used when the base station instructs the terminal to perform the RACH process.

The following is a description of the random access procedure provided by the LTE system. The random access process provided by the LTE system is classified into a contention based random access procedure and a non-contention based random access procedure. The division between the contention-based random access process and the contention-free random access process is determined according to whether the UE directly selects a random access preamble used in the random access process or the base station.

In the contention-free random access procedure, the terminal uses a random access preamble allocated by the base station directly to the base station. Therefore, when the base station allocates the specific random access preamble only to the terminal, the random access preamble uses only the terminal, and other terminals do not use the random access preamble. Therefore, since a 1: 1 relationship is established between the random access preamble and the terminal using the random access preamble, there can be no collision. In this case, as soon as the base station receives the random access preamble, the base station may know the terminal that has transmitted the random access preamble.

On the contrary, in the contention-based random access process, since a random access preamble can be randomly selected and transmitted by the UE, there is a possibility that a plurality of terminals always use the same random access preamble. Therefore, even if a base station receives a certain random access preamble, it is not possible to know which UE transmits the random access preamble.

In general, the UE may perform a random access procedure in the following cases. 1) When the terminal does not have an RRC connection to the base station (initial access) 2) When the terminal is initially connected to the target cell during the handover process 3) When requested by the command of the base station 4 5) Radio link failure or handover when uplink data occurs in a situation in which uplink time synchronization is not correct or a designated radio resource used for requesting a radio resource is not allocated. In case of recovery in case of handover failure.

Based on the above description, Figure 4 shows the operation of the terminal and the base station in the contention-based random access process.

First, in contention-based random access, the UE may randomly select one random access preamble from a set of random access preambles indicated by system information or a handover command, and transmit the random access preamble. The PRACH resource is selected and transmitted to the base station. (Step 1) The preamble at this time is called RACH MSG 1.

After the terminal transmits the random access preamble as described above, the terminal attempts to receive a response to its random access preamble within the random access response reception window indicated by the system information or the handover command (step 2). In more detail, the random access response information is transmitted in the form of a MAC PDU, and the MAC PDU may be transmitted in a physical downlink shared channel (PDSCH). In addition, the physical downlink control channel (PDCCH) is also delivered in order for the terminal to properly receive the information delivered to the PDSCH. That is, the PDCCH may include information of a terminal that should receive the PDSCH, frequency and time information of radio resources of the PDSCH, a transmission format of the PDSCH, and the like. In this case, if the UE succeeds in receiving the PDCCH coming to the UE, the UE properly receives a random access response transmitted to the PDSCH according to the information of the PDCCH. The random access response includes a random access preamble identifier (ID), a UL grant (uplink radio resource), a temporary C-RNTI (temporary cell identifier), and a time alignment command. The reason why the random access preamble identifier is necessary is that since one random access response may include random access response information for one or more terminals, which terminal the UL Grant, Temporary C-RNTI and Time Alignment Command information are valid for It is to inform. The random access preamble identifier corresponds to the random access preamble selected by the user in step 1.

When the terminal receives a random access response valid for the terminal, the terminal processes the information included in the random access response. That is, the terminal applies a Time Alignment Command and stores a Temporary C-RNTI. In addition, by using the UL Grant, data stored in the buffer of the terminal or newly generated data is transmitted to the base station (step 3). At this time, among the data (hereinafter also referred to as message 3) included in the UL Grant, an identifier of the terminal must be included. This is because, in the contention-based random access process, it is not possible to determine which terminals perform the random access process in the base station, since the terminal needs to be identified for future collision resolution. Here, there are two methods for including the identifier of the terminal. In the first method, if the UE already has a valid cell identifier assigned to the cell before the random access procedure, the UE transmits its cell identifier through the UL Grant. On the other hand, if a valid cell identifier has not been allocated before the random access procedure, the terminal transmits its own unique identifier (eg, S-TMSI or Random Id). In general, the unique identifier is longer than the cell identifier. In step 3, if the UE transmits data through the UL Grant, the UE starts a contention resolution timer.

After the terminal transmits data including its identifier through the UL Grant included in the random access response, the terminal waits for instructions from the base station to resolve the collision. That is, it attempts to receive the PDCCH to receive a specific message (step 4). Here, there are two methods for receiving the PDCCH. As mentioned above, when its identifier transmitted through the UL Grant is a cell identifier, it attempts to receive a PDCCH using its cell identifier, and when the identifier is a unique identifier, it is included in the random access response. Attempt to receive the PDCCH using the Temporary C-RNTI. Then, in the former case, if the PDCCH (hereinafter referred to as message 4) is received through its cell identifier before the conflict resolution timer expires, the UE determines that the random access procedure has been normally performed, and randomly Terminate the access process. In the latter case, if the PDCCH is received through the temporary cell identifier before the conflict resolution timer expires, the data (hereinafter referred to as message 4) transmitted by the PDSCH indicated by the PDCCH is checked. If the unique identifier is included in the content of the data, the terminal determines that the random access procedure has been normally performed, and ends the random access procedure. Here, the message or MAC PDU received in this fourth step is often called RACH MSG 4.

The following describes a method for the UE to receive data in the downward direction in the LTE system. 5 is an exemplary diagram illustrating a radio resource allocation according to the prior art.

In the down direction, physical channels are divided into two types, which are a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH). PDCCH is not directly related to transmission of user data, and control information necessary for operating a physical channel is transmitted. In the simplest case, the PDCCH may be used to control other physical channels. In particular, the PDCCH is used to transmit information necessary for the UE to receive the PDSCH. At any particular point in time, information is transmitted through the PDCCH, such as which data is transmitted using which specific frequency band, for which UE, what size of data is transmitted, and the like. Accordingly, each UE receives a PDCCH at a specific TTI, checks whether the data to be received is transmitted through the PDCCH, and if it is informed that the data to be received is transmitted, it is indicated by the PDCCH. PDSCH is further received using information such as frequency. Data of the PDSCH is transmitted to which UE (one or a plurality of UEs), and information on how the UEs should receive and decode the PDSCH data includes physical channel physical downlink control channel (PDCCH). It can be said to be included in the transmission.

For example, in a specific subframe, radio resource information A (e.g., frequency position) and transmission format information B (e.g., transport block size, modulation and coding information, etc.) are RNTI (Radio Network). Assume that CRC is masked with Temporary Identity and transmitted through PDCCH. One or more terminals in the cell monitor the PDCCH using their own RNTI information. In the above assumption, a CRC error does not occur when the terminal decodes the PDCCH with an RNTI of C. Will not. Accordingly, the terminal receives the data by decoding the PDSCH using the transmission type information B and the radio resource information A. On the other hand, in the above assumption, a CRC error occurs when the PDCCH is decoded in a terminal that does not have an RNTI of C. Therefore, the terminal does not receive the PDSCH.

In this process, a radio network temporary identifier (RNTI) is transmitted to inform UEs about which radio resources are allocated through each PDCCH. There are a dedicated RNTI and a common RNTI. The dedicated RNTI is assigned to one terminal and used for transmitting and receiving data corresponding to the terminal. The dedicated RNTI is allocated only to a terminal whose information is registered in the base station. On the contrary, the common RNTI is used when terminals that do not have a dedicated RNTI assigned because information is not registered in the base station exchange data with the base station, or transmit information commonly applied to a plurality of terminals such as system information.

First, the structure of the MAC PDU (Medium Access Control Protocol Data Unit) used in the MAC entity will be described. 6 shows a format of a MAC PDU used by a MAC entity. In FIG. 6, the LCID indicates which logical channel the MAC SDU corresponds to, and the L field indicates the size of the corresponding MAC SDU. The E field additionally indicates whether headers exist. In the above process, if the size of the corresponding MAC SDU or MAC Control Element is less than or equal to 127, the 7-bit L field illustrated in FIG. 7 is used, and if the size of the corresponding MAC SDU or MAC Control Element is greater than 127 If large, an L field of 15 bits is used. A MAC sub-header of the type shown in FIG. 7 (b) is used for a MAC sub-header or a fixed MAC control element for the MAC SDU included in the MAC PDU. In this case, a MAC subheader of the type shown in Fig. 7 (a) is used.

The following is a more detailed description of each field used in FIG.

LCID: This tells which logical channel the MAC SDU is or what information the MAC Control Element (MAC) contains.

-E: This indicates whether there is another MAC sub-header behind this MAC sub-header.

F: tells the length of the following L field.

R: reserved bit, unused bit.

Here, the information on the values used for the LCID can be represented by the following table.

In general, a terminal that has not established an RRC connection has to establish an RRC connection with a base station when a call starts. At this time, the terminal to perform the RACH process. In addition, the terminal in the RRC connection state, if there is no uplink radio resource allocated to the self, if the data that needs to be transmitted upwards, should perform the RACH process. In both cases, the UE configures a MAC PDU having a size corresponding to the information included in the random access response received in the second step of the RACH process, and uses the radio resource indicated by the information to inform the base station. It will send a MAC PDU. At this time, the total amount of data that the UE can transmit in the upward direction, that is, the size of the MAC PDU is approximately 56 bits.

In addition, the first RRC message transmitted by the terminal that has not established the RRC connection is an RRC Connection Request message, which is approximately 56 bits in size. However, the RRC message is delivered in the form of MAC SDU to the MAC layer via the RLC layer. In order to configure the MAC PDU, a MAC header and a MAC SDU are required, where the minimum size of the MAC header is 8 bits in consideration of only one MAC subheader. Therefore, if the MAC PDU including only the RRC connection request message is configured, it is at least 64 bits, which is larger than the size of the message that can be sent in the third step of the RACH process.

On the other hand, the message transmitted by the UE, which has established the RRC connection, to request the allocation of radio resources to the base station is a Buffer Status Report (BSR). There are two types of Buffer Status Report (BSR), the largest of which is 32 bits including the MAC Subheader. In addition, at this time, the terminal should send its information to the base station, which is a MAC C-RNTI CE (Control Element), which is 24bit, including the MAC Subheader. Therefore, the size of the MAC PDU configured in this case is 56 bits, which may be transmitted in the third step in the RACH process.

In the third step of the RACH process, in order to send the RRC connection request message, 1) the size of the MAC PDU that can be sent in the third step of the RACH process must be increased, or 2) the size of the RRC connection request message must be reduced. If the size of the MAC PDU that can be transmitted in the third step of the RACH process may be increased by 64 bits, in this case, the UE in the RRC connection state needs to include 8 bits unnecessarily in the MAC PDU.

In addition, if the size of the RRC connection request message is reduced, the UE additionally performs another RACH process to send the remaining information, which causes a problem in that it takes longer to establish an RRC connection. In the above process, when the RRC connection request message is included in the MAC PDU, if the MAC Subheader is not included, the MAC PDU may be configured according to the limitation of 56 bits, but when the receiver receives the MAC PDU, There is a problem that the side does not know whether the RRC connection request message or the Buffer Status Report (BSR) is included in the MAC PDU.

Therefore, the present invention intends to provide a method of increasing the efficiency of data transmission in the process of sending and receiving data between the base station and the terminal.

In order to solve the above problems of the present invention, a method of communicating data in a wireless communication system, comprising: receiving at least one data from a higher layer; Selecting one error checking function from error-checking functions configured according to the received at least one data; Processing the received at least one data using the selected error checking function; And transmitting the processed data.

Preferably, the upper layer is a medium access control (MAC) layer or a radio link control (RLC) layer.

Preferably, the at least one data is a medium access control protocol data unit (MAC PDU) or a radio link control protocol data unit (RLC PDU).

Preferably, the error checking function is a CRC (Cyclic Redundancy Check) function.

Preferably, the error checking function is selected according to a data format of the received at least one data.

Preferably, the error checking function is selected according to a reception channel of the received at least one data.

Preferably, the received at least one data is processed by applying the selected error checking function to the at least one received data.

In addition, to solve the above problems of the present invention, a method of communicating data in a wireless communication system, comprising the steps of: receiving at least one data; Processing the received at least one data using all error checking functions within configured error checking functions; Determining which error checking function has been successfully performed on the received at least one data; And decoding the received at least one data using the configuration related to the determined error checking function.

Preferably, the error checking function is a CRC (Cyclic Redundancy Check) function.

Preferably, the determining step is characterized in that performed by the physical layer of the network.

Preferably, the decrypting step is performed by a medium access control (MAC) layer of the network.

In addition, to solve the above problems of the present invention, a method of communicating data in a wireless communication system, comprising: receiving at least one data from a higher layer; Selecting a preamble according to the received at least one data; Transmitting the selected preamble; Receiving a response message in response to the selected preamble, wherein the response message includes allocated radio resources for a next scheduled data transmission, and next scheduled data using the configuration associated with the selected preamble. Characterized in that it comprises the step of transmitting.

Preferably, the preamble is a random access channel (RACH) preamble.

Preferably, the configuration is characterized in that used to generate a MAC PDU (Medium Access Control Protocol Data Unit).

Preferably, the MAC Medium Access Control Protocol Data Unit (PDU) is generated by including or not including a header.

In the present invention, when the terminal transmits the RACH message 3 (MSG 3) to the base station, by applying a different CRC algorithm according to the type of data included in the RACH MSG 3 to transmit the RACH MSG 3, to the RACH MSG 3 This reduces the overhead of the MAC PDU involved, resulting in higher data transmission efficiency.

The present invention is applied to 3GPP communication technology, in particular UMTS (Universal Mobile Telecommunications System) system, communication device and communication method. However, the present invention is not limited thereto and may be applied to all wired and wireless communication to which the technical spirit of the present invention can be applied.

The basic concept of the present invention is a method of communicating data in a wireless communication system, comprising: receiving at least one data from a higher layer; Selecting one error checking function from error-checking functions configured according to the received at least one data; Processing the received at least one data using the selected error checking function; And it proposes a method for communicating data in a wireless communication system comprising the step of transmitting the processed data and a wireless mobile communication terminal and a wireless network capable of performing such a method.

A method of communicating data on a wireless communication system, the method comprising: receiving at least one data; Processing the received at least one data using all error checking functions within configured error checking functions; Determining which error checking function has been successfully performed on the received at least one data; And decoding the received at least one data using the configuration related to the determined error checking function, and suggesting a method of communicating data on a wireless communication system, and performing such a method. A wireless mobile communication terminal and a wireless network are proposed.

A method of communicating data on a wireless communication system, the method comprising: receiving at least one data from an upper layer; Selecting a preamble according to the received at least one data; Transmitting the selected preamble; Receiving a response message in response to the selected preamble, wherein the response message includes allocated radio resources for a next scheduled data transmission, and next scheduled data using the configuration associated with the selected preamble. A method for communicating data in a wireless communication system, comprising the step of transmitting the data, and a wireless mobile communication terminal and a wireless network capable of performing the method are proposed.

First, the present invention proposes a method for transmitting a data block (or data unit) effectively by providing a method for a transmitting side to inform a receiving side of the content or type of a data block to be transmitted without using additional radio resources. We want to implement More specifically, the present invention provides a method for a receiver to know the content or type of a data block included in the MAC PDU without using information included in a medium access control protocol data unit (MAC PDU). I would like to present.

To this end, the present invention proposes that the transmitting side transmits by applying different processing methods according to the characteristics of the data to be transmitted. In addition, the receiving side applies different processing methods to the received data block, and then, based on the result, identifies the characteristics of the received data block and proposes to process the received data block accordingly. In the above process, the characteristic of the data to be transmitted is a type of data included in the data block in the transmitting side of the data to be transmitted, or which logical channel the data block is received from, or the data block. It means the data received from this higher layer. In addition, the data block to be transmitted in the above process means a MAC PDU (Medium Access Control Protocol Data Unit), a Transport Block (TB), or a PDU (Protocol Data Unit). In addition, the type of data included in the data block in the process may include whether the data is a control message or user data, whether the data is an RRC message, or whether the data is a CCCH message or not. Indicates whether or not it is a MAC Control Element (CE).

In addition, the data received from the logical channel in the process, whether the data is received from the common control channel (Common Control Channel), or whether it is received from the dedicated control channel (Dedicated Control Channel), or dedicated traffic Whether it is data received from a dedicated traffic channel, or data received from a common traffic channel, or data received from a broadcast control channel, or a multimedia broadcast control channel (MBMS Control). Whether or not it is data received from a channel or data received from a multimedia broadcasting traffic channel (MBMS Traffic Channel). In addition, the data received from the upper layer in the above process means that, when the sender configures and transmits the data block, whether the data included in the data block is data received from the upper layer or data generated by itself. Means. Also, in the above process, the data created by the user himself or herself means a control message that the user directly configures and includes. In addition, in the above process, the control message that is configured by itself includes a MAC control element.

In addition, different processing methods in the above process means that different CRC algorithms are applied. That is, it means that the result obtained by using different CRC algorithm is applied to the data block and transmitted. Alternatively, different processing methods mean that different parity algorithms are applied. In other words, the result obtained by using different parity algorithm is applied to the data block and transmitted. Alternatively, different processing methods mean that different security algorithms are applied. That is, it means that the result obtained by using different security algorithm is applied to the data block and transmitted. Alternatively, different treatments mean that different robust algorithms are applied. In other words, the result obtained by using different robust algorithm is applied to the data block and transmitted. In this case, the robust algorithm means a method capable of determining whether or not an error exists in a data block.

To illustrate the above processes in more detail, the following example is given. First, suppose that a processing method A and a processing method B are set on the transmitting side. In addition, it is assumed that the processing method A is used for processing data having the characteristic of C, and the processing method B is used for processing the data having the characteristic of D. In this case, each time the data block is transmitted, the transmitting side identifies the characteristics of the data included in the data block, determines a processing method to be applied accordingly, and applies the determined processing method to the data block. For example, when the data block to be transmitted includes data of characteristic C, the transmitting side applies the processing method A to transmit the data block. For example, when the data block to be transmitted includes data of characteristic B, the transmitting side applies the processing method D to transmit the data block.

In the above process, different processing methods mean that different parameters are used according to characteristics of data. Alternatively, different processing methods mean that different parameters are used for the use of the CRC value according to the characteristics of the data. Alternatively, different processing methods mean that different CRC masking is used according to characteristics of data.

For example, different parameters may be used to calculate the CRC depending on the characteristics of the data, different Radio Temporary Network Identity (RNTI) may be used, or different RNTI may be used for the CRC algorithm or the like.

In the above process, the receiving side applies different processing methods to the received data block, and then processes according to the result. The receiving side applies all the processing methods set to the received data block, and then finishes successfully. After confirming the method, it means that the characteristics of the data block associated with the processing method are checked and the received data block is processed accordingly.

Specifically, it is assumed that processing method A and processing method B are set on the receiving side. In addition, it is assumed that the processing method A is used for processing data having the characteristic of C, and the processing method B is used for processing the data having the characteristic of D. In this case, the receiving side applies the processing method A and the processing method B each time a data block is received. At this time, the receiving side checks, among the above processing methods, which processing method has been successfully completed. For example, when the processing method A is successfully completed for the received data block, the terminal assumes that the data block includes data having the characteristic C and performs further processing. For example, when the processing method B is successfully completed for the received data block, the terminal assumes that the data block includes data having the characteristic D and performs further processing.

Hereinafter, the configuration and operation of the embodiments according to the present invention will be described with reference to the accompanying drawings.

FIG. 8 is an exemplary diagram illustrating an operation of encrypting or decoding a data unit using a plurality of CRC formulas according to the present invention. In the above example, it is assumed that there are two kinds of data and two kinds of CRC formulas (formula, algorithm). In the above example, it is assumed that CRC formula 1 is used to transmit data transmitted through a common control channel (CCCH) channel, and CRC formula 2 is used to transmit data other than the CCCH channel. In the above example, when the transmitter configures and transmits a MAC PDU, the transmitter determines whether the data included in the MAC PDU is CCCH, and if CCCH data is included, applies the CRC formula 1 to the MAC PDU and transmits it. In the above example, when the transmitter configures and transmits a MAC PDU, the transmitter determines whether the data included in the MAC PDU is CCCH, and if the CCCH data is not included, applies the CRC formula 2 to the MAC PDU and transmits it. . In the above example, the receiving side applies both CRC formula 1 and CRC formula 2 to the received data block and checks which side the CRC success occurs. If the CRC check is successfully completed in the CRC formula 1, the receiver concludes that the data block, that is, the MAC PDU contains data of the CCCH, and processes the MAC PDU. If the CRC check is successful in CRC Equation 2, the receiver determines that the data block, that is, the MAC PDU does not include the data of the CCCH, and processes the MAC PDU.

In the above process, the CRC formula means an algorithm or a hash function for generating a CRC value. In the example of FIG. 8, Formula 1 and Formula 2 use the same CRC algorithm, but may be implemented by using input values, for example, different RNTIs. In addition, in the above process, when the type or characteristic of the data is confirmed, the receiving side may reassemble the MAC PDU according to the MAC PDU structure. For example, if a CCCH is included in a MAC PDU, the MAC PDU is reassembled without including the MAC Subheader, and if other data except the CCCH is included in the MAC PDU, the MAC PDU is included in the MAC PDU. Can be reassembled. Therefore, the transmitting side and the receiving side may use different MAC PDU structures according to data characteristics.

The present invention also proposes to classify the RACH access preamble in another way that can solve the problems described above. That is, when transmission of a CCCH message or a specific message is required, the UE selects and transmits a specific preamble group. At this time, when the base station receives a preamble belonging to the specific preamble group, the base station allocates more bits to the preamble. 9 is a diagram illustrating a method for operating by setting a specific message or data of a specific channel for each random access preamble group according to the present invention. As shown in FIG. 9, the terminal selects a preamble group and transmits one of the preambles according to whether the message to be transmitted is a CCCH message. That is, according to the present invention, a separate random access preamble group is set for transmission of a specific message or data of a specific channel, and when a terminal needs to transmit data of a specific channel or a specific message, the separate random access preamble is set. To choose. In this case, information about a specific channel, a specific message, and a specific preamble group may be informed by the base station to the terminal.

Hereinafter, a terminal according to the present invention will be described.

The terminal according to the present invention includes all types of terminals that can use a service that can exchange data with each other over the air. That is, the terminal according to the present invention is a mobile communication terminal capable of using a wireless communication service (for example, user equipment (UE), mobile phone, cellular phone, DMB phone, DVB-H phone, PDA phone, and PTT phone, etc.) It is a comprehensive meaning including laptops, laptops, laptops, digital TVs, GPS navigation, handheld game consoles, MP3s, and other consumer electronics.

The terminal according to the present invention may include a basic hardware configuration (transmitter / receiver, processor or controller, storage, etc.) required to perform functions and operations for efficient system information reception illustrated in the present invention.

The method according to the invention described thus far can be implemented in software, hardware, or a combination thereof. For example, the method according to the present invention may be stored in a storage medium (eg, internal memory of a mobile terminal or base station, flash memory, hard disk, etc.) and may be stored in a processor (eg, mobile terminal or base station). Code or instructions within a software program that can be executed by an internal microprocessor).

In the above, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary and will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a network structure of E-UTRAN, which is a mobile communication system to which the present invention and the present invention are applied.

Figure 2 is an exemplary view showing a control plane structure of a radio interface protocol between the terminal and the E-UTRAN in the prior art.

3 is an exemplary diagram illustrating a user plane structure of a radio interface protocol between a terminal and an E-UTRAN in the prior art.

4 is an exemplary diagram illustrating a contention based random access procedure.

5 is an exemplary diagram illustrating a radio resource allocation according to the prior art.

6 is an exemplary diagram illustrating a format of a protocol data unit (PDU) used in a medium access control (MAC) entity.

7 (a) and 7 (b) are exemplary diagrams illustrating a MAC subheader format used in a medium access control (MAC) entity.

8 is an exemplary diagram illustrating an operation of encoding or decrypting a data unit using a plurality of CRC formulas according to the present invention.

9 is an exemplary diagram illustrating a method of operating a specific message or data of a specific channel by setting a random access preamble group according to the present invention.

Claims (15)

A method of communicating data on a wireless communication system, Receiving at least one data from an upper layer; Selecting one error checking function from error-checking functions configured according to the received at least one data; Processing the received at least one data using the selected error checking function; And Transmitting the processed data. The method of claim 1, wherein the upper layer is a medium access control (MAC) layer or a radio link control (RLC) layer. The method of claim 1, wherein the at least one data is a Medium Access Control Protocol Data Unit (MAC PDU) or a Radio Link Control Protocol Data Unit (RLC PDU). The method of claim 1, wherein the error checking function is a cyclic redundancy check (CRC) function. The method of claim 1, wherein the error checking function is selected according to a data format of the received at least one data. The method of claim 1, wherein the error checking function is selected according to a reception channel of the received at least one data. 2. The method of claim 1, wherein said at least one received data is processed by applying said selected error checking function to said received at least one data. A method of communicating data on a wireless communication system, Receiving at least one data; Processing the received at least one data using all error checking functions within configured error checking functions; Determining which error checking function has been successfully performed on the received at least one data; And Decrypting the received at least one data using a configuration related to the determined error checking function. 10. The method of claim 8, wherein the error checking function is a cyclic redundancy check (CRC) function. 9. The method of claim 8, wherein said determining step is performed by a physical layer of a network. 9. The method of claim 8, wherein said decrypting step is performed by a medium access control (MAC) layer of a network. A method of communicating data on a wireless communication system, Receiving at least one data from a higher layer; Selecting a preamble according to the received at least one data; Transmitting the selected preamble; In receiving a response message in response to the selected preamble, the response message includes an allocated radio resource for a next scheduled data transmission, and Transmitting next scheduled data using the configuration associated with the selected preamble. 13. The method of claim 12 wherein the preamble is a Random Access Channel (RACH) preamble. 13. The method of claim 12, wherein the configuration is used to generate a Medium Access Control Protocol Data Unit (MAC PDU). 15. The method of claim 14, wherein the Medium Access Control Protocol Data Unit (MAC PDU) is generated with or without a header.

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