CN101155421B - Method and device for distributing temporary recognition number of subdistrict wireless network - Google Patents

Abstract

A method for allocating C-RNTI by a base station, comprising steps: a user equipment sends a random access preamble to a base station; a base station sends a response message of a random access preamble to the user equipment, and the message includes: allocation information of uplink resources, timing adjustment information, and combined with the random access preamble sequence identification number to indicate the CRNTI information. The user equipment will send an L3 message to the network; the network will send a response to the L3 message to the user equipment. Compared with the traditional C-RNTI allocation method, the present invention utilizes the random access preamble sequence used by the user equipment and detected by the base station, sends subframes, and sends random access channel information to group C-RNTI, thereby reducing C-RNTI The indication information bits required for RNTI allocation reduce the signaling burden required for C-RNTI allocation, optimize the random access process, and improve the performance of random access.

Description

Method and device for allocating temporary identification number of residential wireless network

technical field

The invention relates to a method for distributing cell radio network temporary identification number (C-RNTI) used for asynchronous random access process in a mobile radio communication system.

Background technique

Now, the third generation partnership project (referred to as 3GPP) standardization organization has begun to carry out long-term evolution (LTE) of its existing system specifications. According to the current discussion about LTE, Orthogonal Frequency Division Multiplexing (OFDM) technology will be used as the downlink physical layer transmission technology in LTE, and single carrier frequency division multiple access (SC-FDMA for short) will be used as the uplink physical layer transmission technology in LTE. Layer transfer technology.

A very important process in the LTE communication system is the random access process, and the random access process is divided into a synchronous random access process and an asynchronous random access process according to whether there is uplink synchronization. The asynchronous random access procedure is used for initial physical channel connection and resource request for uplink scheduling.

The purpose of the user equipment sending an asynchronous random access request to the network includes:

-Receive the timing adjustment from the network side to obtain uplink synchronization;

-Apply to the network for user equipment identification number allocation, that is, apply for the allocation of cell wireless network temporary identification number (C-RNTI);

- sending an uplink resource request for transmitting Layer 2/Layer 3 (L2/L3) messages including Radio Resource Control (RRC) messages, Non-Access Stratum (NAS) messages and scheduling request information.

According to the current LTE discussion on asynchronous random access channels, asynchronous random access includes the following interaction process:

- In the first step, the user equipment sends a random access preamble to the network;

In this step, only the random access preamble is sent. The amount of information that can be carried in the random access preamble is very limited, and the user equipment can implicitly send 4 to 6 bits of information through the random access preamble.

- In the second step, the network end sends the response information of the random access preamble sequence to the user equipment;

The response information includes the timing adjustment (timing adjustment) calculated according to the random access preamble signal, and the uplink resources allocated for the user equipment to send subsequent information. It should be noted that the response information may or may not contain the CRNTI allocated to the user equipment.

- In the third step, the user equipment sends a Layer 2/Layer 3 (L2/L3) message on the uplink resource allocated to it by the network;

The L2/L3 message includes a Radio Resource Control (RRC) message, a Non-Access Stratum (NAS) message, and a Layer 2/Layer 3 (L2/L3) message of scheduling request information.

- In a fourth step, the network sends a response to the L2/L3 message to the user equipment.

If in the random access response in the second step, the network side does not allocate a CRNTI to the user equipment, it will allocate it to the user equipment in this step.

At present, some companies have proposed that when the user equipment sends a random preamble access sequence to the network in the first step, the preamble sequence will be used to indicate the cause (Cause) information for initiating asynchronous random access. The method of indication is to group the preamble sequence. Different sets of preambles will indicate different reasons for asynchronous random access. The reasons for asynchronous random access that can be indicated are listed in the table below:

Table 1 Reasons for asynchronous random access

It can be seen from the above table that if the cause of the preamble indication sent by the user equipment received by the network indicates that the user equipment has or does not have a C-RNTI, if there is already a C-RNTI, then the network will no longer need Allocate the C-RNTI to the user equipment.

For the allocation of C-RNTI, there are currently two methods:

One is to send the allocation of C-RNTI in the response information of the L2/L3 message sent by the network to the user equipment in the fourth step described above.

Another way is to send the allocation of C-RNTI in the response message of the random access preamble sent by the network in the second step described above.

For the first type, the allocation of C-RNTI is sent in the response information of the L2/L3 message sent by the network to the user equipment, then in the second step, there is no C-RNTI in the response message of the random access preamble sent by the network to the user equipment. -RNTI allocation, then in this message, an implicit CRNTI (Implicit CRNTI, I-CRNTI) is required to identify the user equipment before the network end allocates C-RANTI to the user equipment.

The I-CRNTI is a subset of the C-RNTI reserved in the total C-RNTI space (space), and is specially used to represent the user equipment before the user equipment is allocated a C-RNTI during the random access process. Each I-CRNTI in this subset corresponds to a preamble or a combination of a preamble and a subframe number or a combination of a preamble, a subframe number and a random access channel frequency domain sequence number. In this way, when the user equipment selects the random preamble or the random preamble and the transmission subframe or the random preamble, after the frequency domain sequence number of the transmission subframe and the transmission random access channel, it knows the corresponding I-CRNTI, This enables the user equipment to receive the message sent by the network to the user equipment according to the I-CRNTI even though the user equipment does not have a C-RNTI allocated.

The advantage of this method is that before the random collision is completely resolved, there is no C-RNTI allocation, which avoids the signaling burden brought by the C-RNTI allocation. However, the disadvantage of this method is that the C-RNTI space needs to reserve additional space for the I-CRNTI. If the I-CRNTI corresponds to the preamble sequence, since different users may use the same preamble sequence to initiate random access at different times or on different frequencies, the network end transmits the I-CRNTI when sending a message to the user equipment. In addition, the user equipment needs to be instructed to send the subframe number of the preamble sequence and the sequence number in the frequency domain, which may introduce additional signaling burden. However, if the I-CRNTI corresponds to the combination of the preamble sequence, the subframe number and the frequency domain sequence number, then the corresponding reserved space will be larger.

For the second method of C-RNTI allocation, the network end directly allocates C-RNTI in the response message of the preamble sequence, so that the response message of the preamble sequence will contain the identification number RA_ID corresponding to the preamble sequence, and the uplink resource allocation ( UL-RA), timing adjustment (Timing Adjustment, TA) and C-RNTI. Although in this way, the user equipment can obtain the allocation of C-RNTI earlier, but because the length of the C-RNTI sequence is long, and the network end cannot obtain accurate channel quality information when sending the response of the preamble sequence to the user equipment, At this time, the signaling burden of allocating the C-RNTI to the user equipment is relatively large. In addition, some companies currently propose to use the L1/L2 control channel to send the response of the random access preamble to the user equipment, although the use of the L1/L2 control channel to transmit the response of the preamble will avoid the signaling burden required for allocating the downlink shared data channel. However, since the burden of transmitting the C-RNTI is too great, it is almost impossible to use the L1/L2 control channel to transmit the allocation of the C-RNTI.

Therefore, it is necessary to improve the C-RNTI allocation method to reduce the corresponding signaling burden of C-RNTI allocation, so as to optimize the random access process and improve the random access performance.

Contents of the invention

In view of the above problems, the purpose of the present invention is to propose a C-RNTI allocation method to reduce the corresponding signaling burden of C-RNTI allocation, optimize the random access process, and improve the efficiency of random access.

According to one aspect of the present invention, a method for a base station to allocate C-RNTI includes steps:

a) The user equipment sends a random access preamble to the base station;

b) The base station sends a response message of the random access preamble to the user equipment, and the message includes: allocation information of uplink resources, timing adjustment information, and information indicating CRNTI combined with the identification number of the random access preamble;

c) The user equipment will send an L3 message to the network;

d) The network end will send a response to the L3 message to the user equipment.

According to another aspect of the present invention, a base station device for implementing C-RNTI allocation includes an antenna, adding a cyclic prefix, an OFDM modulation module, modulation, rate matching, and a channel coding/interleaving module, and also includes:

a) a random access preamble detector, used to detect the random access preamble sent by the user equipment, identify the sending subframe and send the random access channel;

b) The controller is used to determine the sent subframe and the sent random access channel according to the random access preamble detected by the random access preamble detector with reference to the group correspondence determined in the C-RNTI group correspondence module. The C-RNTI group of the random access preamble sequence response, and select a suitable C-RNTI in the group, and then pass it to the control information generator to generate the control information allocated by the CRNTI;

c) a sending device, configured to send control information allocated by the C-RNTI.

Compared with the traditional C-RNTI allocation method, the present invention utilizes the random access preamble sequence used by the user equipment and detected by the base station, sends subframes, and sends random access channel information to group C-RNTI, thereby reducing C-RNTI The indication information bits required for RNTI allocation reduce the signaling burden required for C-RNTI allocation, optimize the random access process, and improve the performance of random access.

Description of drawings

Fig. 1 is the operation steps of the base station in the first implementation mode of the C-RNTI allocation method of the present invention;

Fig. 2 is the operation steps of the base station in the first implementation mode of the C-RNTI allocation method of the present invention;

Fig. 3 is the random access process signaling interaction of sending C-RNTI assignment in the response message of the preamble sequence;

Fig. 4 is the signaling interaction of the random access procedure for sending the C-RNTI assignment in the response message of the L2/L3 message;

Fig. 5 is the operation steps of the base station in the second implementation mode of the C-RNTI allocation method of the present invention;

Fig. 6 is the response information format of the random access preamble sent by the base station to the user equipment;

Fig. 7 is the operation steps of the user equipment in the second implementation mode of the C-RNTI allocation method of the present invention;

FIG. 8 shows the signaling interaction between the user equipment and the base station in the second implementation mode of the C-RNTI allocation method of the present invention;

Fig. 9 is a hardware implementation block diagram of the base station in the C-RNTI allocation method of the present invention;

FIG. 10 is the format of the random access preamble response message transmitted in the L1/L2 control signaling;

Fig. 11 is a block diagram of hardware implementation of base station allocating C-RNTI in the embodiment.

Detailed ways

The C-RNTI allocation method proposed by the present invention is to reduce the number of information bits required for C-RNTI allocation by grouping the C-RNTI spaces, specifically based on the random access preamble, or the preamble and random access The combination of subframe numbers, or the combination of preamble sequence, random access subframe number, and random access frequency domain channel number, groups the C-RNTI space, and the network side sends random access according to the user equipment. The preamble sequence, or the selected preamble sequence and the transmitted subframe number, or the selected preamble sequence, the transmitted subframe number and the transmitted frequency domain channel number, determine the group in which the CRNTI allocated to the user is located, and within this group Select an unused C-RNTI and assign it to the user. Since the C-RNTIs that can be allocated are only a subset of the entire C-RNTI space, the number of information bits required to indicate the allocated C-RNTIs in this subset will be smaller than the number of information bits required to indicate the allocated C-RNTIs in the entire C-RNTI space. The number of bits required by the C-RNTI, thereby reducing the corresponding signaling burden of indicating the C-RNTI.

The invention proposes a C-RNTI allocation method, and provides steps and equipment for realizing the C-RNTI allocation method.

First of all, the present invention provides the first implementation in order to realize the proposed C-RNTI allocation method. In this implementation, the required operation steps of the base station are shown in Figure 1:

First, the base station learns the grouping mode of the C-RNTI allocated to the user equipment (101). The method for the base station to know the grouping method of the C-RNTI for the user equipment may be fixed by the specification; it may also be that other nodes at the network end configure the grouping method and notify the base station through signaling; it may also be The base station determines the grouping method of C-RNTI by itself. For example, the base station determines the grouping method of C-RNTI according to its configuration of random sequences and random channels, or determines the C-RNTI grouping method according to the configuration of random sequences and/or random channels of other nodes on the network side. - How the RNTIs are grouped.

Afterwards, the base station receives the random access preamble sent by the user equipment to determine the C-RNTI group corresponding to the random access request (102);

Then, the base station determines the C-RNTI group allocated to the user equipment, and selects a C-RNTI in the C-RNTI group to send a C-RNTI assignment to the user equipment (103). The specific implementation of this step is: the base station selects a C-RNTI that has not been allocated in the determined C-RNTI group, and sends the selected C-RNTI to the user equipment when it needs to allocate a C-RNTI to the user equipment The sequence numbers in this group enable C-RNTI assignment.

In step 103, the C-RNTI assignment sent by the base station to the user equipment can be transmitted in the response message of the random access preamble, or in the response message of the layer 2/layer 3 (L2/L3) message sent by the base station to the user equipment information is transmitted. If it is transmitted in the response message of the random access preamble sequence, the C-RNTI assignment can be transmitted in the Layer 1/Layer 2 (L1/L2) control channel, or in the downlink shared data channel.

It should be noted that, according to the allocation method of the above C-RNTI group, the C-RNTI allocation in a certain C-RNTI group may be exhausted. In order to avoid such depletion, the above allocation method may further include a step: the base station sends C-RNTI reallocation signaling to some user equipments that have completed the random access process.

The base station sends C-RNTI reassignment signaling to some user equipments that have been connected, so that they can use C-RNTIs of other groups and release the C-RNTIs of the original C-RNTI group, which can avoid some C-RNTIs The allocation of C-RNTIs in the group is exhausted.

In the method of the present invention, the grouping of the C-RNTI space allocated to the user equipment can have the following methods:

C-RNTI space grouping method 1:

C-RNTI spatial grouping method 1 is a grouping method based on random access preambles. Assuming that the number of preambles used for grouping is N _RS , a grouping method can be given as shown in formula (1). Assuming that there are N _T C-RNTIs in the entire C-RNTI space, and the serial number of the C-RNTI in the entire C-RNTI space is n, then the serial number n _g of the group to which the C-RNTI with the serial number n belongs is:

n _g = n mod N _RS 0≤n≤N _T (1)

According to formula (1), the preamble-based C-RNTI grouping method can be given as shown in Table 2.

Table 2C-RNTI space grouping based on preamble

C-RNTI space grouping method 2:

The C-RNTI spatial grouping method 2 is a grouping method based on a combination of a random access preamble sequence and a transmission subframe (or transmission frame). The purpose of grouping C-RNTIs based on transmission subframes (or transmission frames) is to group C-RNTIs with reference to random access transmission time (time reference to the RA). Assuming that the number of preamble sequences used for grouping is N _RS , and the number of random access subframes (or frames) that can be transmitted in one random access transmission cycle is N _FN , then a The grouping method is shown in formula (2). Assuming that there are N _T C-RNTIs in the entire C-RNTI space, and the serial number of the C-RNTI in the entire C-RNTI space is n, then the serial number n _g of the group to which the C-RNTI with the serial number n belongs is:

n _g ＝nmod(N _RS *N _FN )0≤n≤N _T (2)

According to the formula (2), the C-RNTI grouping method based on the combination of the preamble sequence and the transmission subframe (or transmission frame) can be given as shown in Table 3.

Table 3C-RNTI space grouping method based on combination of preamble sequence and transmission subframe (or transmission frame)

C-RNTI space grouping method 3:

The C-RNTI spatial grouping method 3 is a grouping method based on a combination of a random access preamble sequence, a transmission subframe (or a transmission frame) and a sequence number in the frequency domain of the transmitted random access channel. The purpose of grouping C-RNTIs based on random access channel frequency domain sequence numbers is to group C-RNTIs with reference to the frequency of random access transmission (frequency reference to the RA). It is assumed that the number of preamble sequences used for grouping is N _RS , and the number of random access subframes (or frames) that can be transmitted in one random access transmission period is N _FN , and the same random access transmission The number of random access channels in a subframe (or frame) is N _CN , then a grouping method can be given as shown in formula (3). Assuming that there are N _T C-RNTIs in the entire C-RNTI space, and the serial number of the C-RNTI in the entire C-RNTI space is n, then the serial number n _g of the group to which the C-RNTI with the serial number n belongs is:

n _g ＝nmod(N _RS *N _FN *N _CN )0≤n≤N _T (3)

According to the formula (3), the C-RNTI grouping method based on the combination of the transmission subframe (or transmission frame) and the frequency domain sequence number of the transmission random access channel can be given as shown in Table 4.

As shown in Table 1 above, the preamble sequence of random access may indicate different reasons, some of which indicate that the user equipment has a C-RNTI, and some of which indicate that the user equipment does not have a C-RNTI. Assuming that the number of sequences used to indicate that the user equipment does not have a C-RNTI is N _NC , then the number of preamble sequences used for grouping in the three C-RNTI grouping methods given here is N _RS may be equal to N _NC , It can also be smaller than N _NC .

With the grouping method of C-RNTI given here, after receiving the random access preamble sent by the user equipment at the network side, it can be based on the preamble, or the combination of the preamble and the transmission subframe (or frame), or The combination of the preamble sequence, the transmission subframe (or frame) and the frequency domain sequence number of the random access channel determines the group where the C-RNTI should be allocated to the user, and selects an unused C-RNTI in this group, And send the sequence number of the C-RNTI in the group to the user equipment so as to realize the allocation of the C-RNTI.

The present invention provides the operation steps required by the user equipment in the first mode of the C-RNTI allocation method, as shown in Figure 2:

First, the user equipment learns the grouping mode allocated by the C-RNTI (201). The method for the user equipment to know the grouping method of the C-RNTI for the user equipment may be fixed by the specification; it may also be that the network side configures the grouping method and notifies the user equipment through signaling; it may also be The user equipment is determined by the user equipment itself according to the configuration of the random sequence and/or the configuration of the random channel at the network side.

Afterwards, when the user equipment needs to initiate random access, it selects a random access preamble, selects a sending subframe (or frame), selects a random access channel, and sends the random access preamble to the base station (202).

Then, the user equipment receives the serial number of the C-RNTI in the C-RNTI group sent by the base station (203), and according to the sent random access preamble, or a combination of the preamble and the sending subframe (or frame), or The combination of the preamble sequence and the sent subframe (or frame) and the sent random access channel, referring to the known grouping method to determine the group where the allocated C-RNTI is located, and determining the allocated group according to the group and sequence number of the C-RNTI C-RNTI.

After the user equipment completes the random access process, start data transmission with the base station (204);

After the random access process is completed, if the base station has a new C-RNTI allocation for it, receive the new C-RNTI allocation sent by the base station, and use the new C-RNTI (205).

According to the method proposed in the present invention, when the base station sends the C-RNTI assignment to the user equipment, that is, sends the sequence number of the C-RNTI in the group, it can be transmitted in the second step of the random access procedure described above, that is It can be transmitted in the response message of the random access preamble sent by the network to the user equipment, or it can be transmitted in the fourth step of the random access process described above, that is, in the L2/L3 message sent by the network to the user equipment. transmitted in the response message.

If the sequence number of the C-RNTI sent by the base station in the packet is transmitted in the response message of the random access preamble, the signaling interaction process between the base station and the user equipment is shown in FIG. 3 .

First, the user equipment sends a random access preamble to the base station (301);

Secondly, the base station sends a random access preamble response message (302) to the user equipment, which will include: allocation of uplink resources, timing adjustment, and the sequence number of the C-RNTI allocated by the base station to the user equipment in the group .

Afterwards, the user equipment will send an L2/L3 message to the network (303);

Then, the network end will send a response to the L2/L3 message to the user equipment (304);

After the user equipment completes the random access process, if the C-RNTI in the C-RNTI group where the C-RNTI used by the user equipment is close to exhaustion, the network will send a C-RNTI reallocation message to the user equipment ( 305), assigning a new C-RNTI in other groups to the user equipment.

Wherein, in step 302, the response message of the random access preamble sent by the base station to the user equipment may also include: allocation information of uplink resources, timing adjustment information, and an identification number (Random Access preamble ID) corresponding to the random access preamble , RA_ID) and information indicating CRNTI combined with RA_ID. Wherein, the information indicating the CRNTI combined with the RA_ID may be the sequence number of the C-RNTI allocated by the base station to the user equipment in the CRNTI group.

Wherein, in step 302, the sequence number of the assigned C-RNTI in the packet can be transmitted in a layer/layer 2 control channel (L1/L2 control channel), or can be transmitted in a downlink shared channel (DL-SCH) .

If the sequence number of the C-RNTI sent by the base station in the packet is transmitted in the response message of the L2/L3 message, the signaling interaction process between the base station and the user equipment is shown in FIG. 4 .

First, the user equipment sends a random access preamble to the base station (401);

Secondly, the base station sends a random access preamble response message (402) to the user equipment, and the message will include information such as allocation of uplink resources and timing adjustment.

After that, the user equipment will send an L2/L3 message to the network (403);

Then, the network end will send a response (404) of the L2/L3 message to the user equipment, which will contain the sequence number information of the C-RNTI sent by the base station to the user equipment in the packet;

After the user equipment completes the random access process, if the C-RNTI in the C-RNTI group where the C-RNTI used by the user equipment is close to exhaustion, the network will send a C-RNTI reallocation message to the user equipment ( 405), assigning a new C-RNTI in other groups to the user equipment.

The method for allocating C-RNTI provided by the present invention has another implementation mode. In this mode, the corresponding operation steps of the base station are shown in FIG. 5 .

First, the base station learns the grouping mode of the C-RNTI allocated to the user equipment (501). The method for the base station to know the grouping method of the C-RNTI for the user equipment may be fixed by the specification; it may also be that other nodes at the network end configure the grouping method and notify the base station through signaling; it may also be The base station determines the grouping method of C-RNTI by itself. For example, the base station determines the grouping method of C-RNTI according to its configuration of random sequences and random channels, or determines the C-RNTI grouping method according to the configuration of random sequences and/or random channels of other nodes on the network side. - How the RNTIs are grouped.

After that, the base station receives the random access preamble sent by the user equipment to determine the C-RNTI group corresponding to the random access request (502);

Then, the base station determines the C-RNTI group allocated to the user equipment, and selects a C-RNTI in the C-RNTI group to send a C-RNTI assignment to the user equipment (503).

In step 503, the C-RNTI assignment sent by the base station to the user equipment can be transmitted in the response message of the random access preamble, or in the response message of the layer 2/layer 3 (L2/L3) message sent by the base station to the user equipment information is transmitted.

If it is transmitted in the response message of the random access preamble sequence, the C-RNTI assignment can be transmitted in the Layer 1/Layer 2 (L1/L2) control channel, or in the downlink shared data channel.

If it is transmitted in the L1/L2 control channel, the specific implementation of this step is: select an available C-RNTI in the determined C-RNTI group as the user's C-RNTI to send the L1/L2 control channel to the user equipment Signaling sends a response to the random preamble. In this step, the sent random preamble response message will include: uplink resource allocation, timing adjustment, C-RNTI and other possible information. Among them, C-RNTI will perform an exclusive OR (XOR) operation with the cyclic redundancy check bit, and then transmit it together (mask CRC). In this step, the format of the response information of the random access preamble sent by the base station to the user equipment is shown in FIG. 6 .

It should be noted that, according to the allocation method of the above C-RNTI group, the C-RNTI allocation in a certain C-RNTI group may be exhausted. In order to avoid such depletion, the above allocation method may further include a step: the base station sends C-RNTI reallocation signaling to some user equipments that have completed the random access process.

The base station sends C-RNTI reassignment signaling to some user equipments that have been accessed, so that they can use the C-RNTI outside the C-RNTI grouping space and release the C-RNTI of the original C-RNTI grouping, which can avoid The allocation of C-RNTIs in some C-RNTI packets in the C-RNTI packet space is exhausted.

In the second mode of the method of the present invention, to group C-RNTIs, first, a subset {C-RNTI _n , N _start ≤ n ≤ N _end } in the total C-RNTI space is used as the C-RNTI grouping space, here The C-RNTIs in the space are C-RNTIs that can be used during and after the random access process, and then these C-RNTIs are grouped. The C-RNTI not grouped will not be allocated to the user as the initial C-RNTI allocation in the initial random access process, but will only be allocated to the user equipment when the C-RNTI is re-allocated after the random access process is completed.

The grouping of the C-RNTI grouping space can be done in the following ways:

Grouping mode 1 of C-RNTI grouping space:

C-RNTI spatial grouping method 1 is a grouping method based on random access preambles. Assuming that the number of preambles used for grouping is N _RS , a grouping method can be given as shown in formula (1). Assume that the serial number of C-RNTI in the entire C-RNTI space is n, and the subset of C-RNTI group space is {C-RNTI _n , N _start ≤ n ≤ N _end }, then in this C-RNTI group space The sequence number n _g of the group to which the C-RNTI with sequence number n belongs is:

n _g = n mod N _RS N _start ≤ n ≤ N _end (4)

Grouping method 2 of the C-RNTI grouping space:

The grouping method 2 of the C-RNTI grouping space is a grouping method based on a combination of a random access preamble sequence and a transmission subframe (or a transmission frame). The purpose of grouping C-RNTIs based on transmission subframes (or transmission frames) is to group C-RNTIs with reference to random access transmission time (time reference to the RA). Assuming that the number of preamble sequences used for grouping is N _RS , and the number of random access subframes (or frames) that can be transmitted in one random access transmission cycle is N _FN , then a The grouping method is shown in formula (5). Assume that the serial number of C-RNTI in the entire C-RNTI space is n, and the subset of C-RNTI group space is {C-RNTI _n , N _start ≤ n ≤ N _end }, then in this C-RNTI group space The sequence number n _g of the group to which the C-RNTI with sequence number n belongs is:

n _g ＝nmod(N _RS *N _FN ) N _start ≤n≤N _end (5)

Grouping mode 3 of the C-RNTI grouping space:

Grouping method 3 of the C-RNTI grouping space is a grouping method based on a combination of a random access preamble sequence, a transmission subframe (or a transmission frame) and a sequence number in the frequency domain of the transmitted random access channel. The purpose of grouping C-RNTIs based on random access channel frequency domain sequence numbers is to group C-RNTIs with reference to the frequency of random access transmission (frequency reference to the RA). It is assumed that the number of preamble sequences used for grouping is N _RS , and the number of random access subframes (or frames) that can be transmitted in one random access transmission period is N _FN , and the same random access transmission The number of random access channels in a subframe (or frame) is N _CN , then a grouping method can be given as shown in formula (6). Assume that the serial number of C-RNTI in the entire C-RNTI space is n, and the subset of C-RNTI group space is {C-RNTI _n , N _start ≤ n ≤ N _end }, then in this C-RNTI group space The sequence number n _g of the group to which the C-RNTI with sequence number n belongs is:

n _g ＝nmod(N _RS *N _FN *N _CN )N _start ≤n≤N _end (6)

As shown in Table 1 above, the preamble sequence of random access may indicate different reasons, some of which indicate that the user equipment has a C-RNTI, and some of which indicate that the user equipment does not have a C-RNTI. Assuming that the number of sequences used to indicate that the user equipment does not have a C-RNTI is N _NC , then the number of preamble sequences used for grouping in the three C-RNTI grouping methods given here is N _RS may be equal to N _NC , It can also be smaller than N _NC .

With the grouping method of C-RNTI given here, after receiving the random access preamble sent by the user equipment at the network side, it can be based on the preamble, or the combination of the preamble and the transmission subframe (or frame), or The combination of the preamble sequence, the transmission subframe (or frame) and the frequency domain sequence number of the random access channel determines the group where the C-RNTI should be allocated to the user, and selects an unused C-RNTI in this group, The C-RNTI is used as the user's identification number, and the response information of the random access preamble is sent to the user equipment in the L1/L2 control channel.

The present invention provides the operation steps required by the user equipment in the second mode of the C-RNTI allocation method, as shown in Figure 7:

First, the user equipment learns the grouping mode allocated by the C-RNTI (701). The method for the user equipment to know the grouping method of the C-RNTI for the user equipment may be fixed by the specification; it may also be that the network side configures the grouping method and notifies the user equipment through signaling; it may also be The user equipment is determined by the user equipment itself according to the configuration of the random sequence and/or the configuration of the random channel at the network side.

Afterwards, when the user equipment needs to initiate random access, it selects a random access preamble, selects a sending subframe (or frame), selects a random access channel, and sends the random access preamble to the base station (702).

Then, the response message of the preamble sent by the base station is received, and the C-RNTI included in the response message is identified (703). The method for the user equipment to identify the C-RNTI is to first determine the grouping of the corresponding C-RNTI according to the transmission of the random access preamble sequence and the transmission of the random access preamble sequence, and then use all the C-RNTIs contained in the group to sequence the preamble sequence The C-RNTI contained in the response message and the field together with the cyclic redundancy check bit mask are detected, so as to identify the C-RNTI contained in the message.

Then the user equipment will send the L2/L3 message to the base station, and receive a response to the L2/L3 message sent by the base station (704).

After the user equipment completes the random access process, start data transmission with the base station (705);

After the random access process is completed, if the base station has a new C-RNTI allocation for it, receive the C-RNTI reallocation message sent by the base station, and use the new C-RNTI (706).

The signaling interaction process between the base station and the user equipment in the second mode of the C-RNTI allocation method given by the present invention is shown in Figure 8:

First, the user equipment sends a random access preamble to the base station (801);

Next, the base station sends a random access preamble response message to the user equipment (802), which will include: allocation of uplink resources, timing adjustment, and C-RNTI allocated by the base station to the user equipment. Among them, the C-RNTI will be together with the cyclic redundancy check bit mask.

Afterwards, the user equipment will send an L2/L3 message to the network (803);

Then, the network end will send a response to the L2/L3 message to the user equipment (804);

After the user equipment completes the random access process, if the C-RNTI in the C-RNTI group where the C-RNTI used by the user equipment is close to exhaustion, the network will send a C-RNTI reallocation message to the user equipment ( 805), allocate a new C-RNTI in the non-C-RNTI grouping space to the user equipment.

The present invention also provides a hardware implementation block diagram of the base station equipment needed to realize the proposed CRNTI allocation method, as shown in Figure 9:

The receiving device 901 of the base station receives the random access preamble sent by the user equipment, inputs it to the random access preamble detector 902, and determines the random access preamble sent by the user equipment, or the random access preamble and the transmission subframe (or frame), or a combination of the random access preamble, the transmission subframe (or frame) and the frequency domain sequence number of the random access channel, and send the detection result to the controller 903 . The controller 903 will refer to the random access preamble, or the combination of the random access preamble and the transmission subframe (or frame), or the frequency of the random access preamble, the transmission subframe (or frame) and the random access channel. Combination of field serial numbers, and correspondence between C-RNTI grouping 904, determine the C-RNTI allocated to the user equipment, and pass the determined C-RNTI to the control information generator 905, and generate the control of allocating C-RNTI message, and send it to the user equipment through the sending means 906.

Example

In order to illustrate the method of the present invention, an embodiment of the C-RNTI allocation method proposed by the present invention is given below.

In the given embodiment, it is assumed that there are a total of 2 ¹⁶ =65536 C-RNTIs in the C-RNTI space of the system, that is to say, 16 bits are required for the system to send a C-RNTI assignment to the user equipment for indication. For example, if according to the existing technology, the network end transmits "0000000000000101" to a certain user equipment in the C-RNTI allocation signaling, it means that the network end allocates the C-RNTI with the sequence number 5 among the 65526 C-RNTIs The user is given the device.

First, an embodiment of the first implementation method of the C-RNTI allocation method proposed by the present invention is given.

Example 1:

The following assumptions are given here:

- The preamble sequence of random access is sent every 10ms interval;

- There are 4 subframes in every 10ms interval that can send the random access preamble;

- There is one random access channel (frequency band with 1.25MHz bandwidth) in each subframe that can send random access preamble;

- There are 64 random access preamble sequences available to the system, 32 of which are used to initiate an asynchronous random access request requiring C-RNTI allocation (the user equipment does not have a C-RNTI).

According to the above assumptions, the C-RNTI space of the system can be grouped as follows according to the method proposed by the present invention:

As shown in the above table, it can be seen that the 65536 C-RNTIs in the C-RNTI allocation space are divided into 32×4=128 according to the different random access preamble sequences sent by the user equipment and the different selected sending subframes groups, and there are 65536/128=512 C-RNTIs in each group.

If both the base station and the user equipment have learned the above-mentioned C-RNTI grouping method, the allocation and identification of the C-RNTI can be performed:

After the base station detects the random access preamble sent by the user equipment, it can determine the random access preamble that should be allocated to it according to the random access preamble selected by the user equipment and the subframe it sends, and according to the grouping relationship in Table 5. C-RNTI grouping, and then you can select a C-RNTI that has not been allocated in the C-RNTI grouping, and assign the 9-bit binary number corresponding to the sequence number of the C-RNTI in the grouping to the user equipment. The RNTI signaling is sent to the user equipment, so that the 9-bit binary number is used to indicate the C-RNTI allocation. Compared with the traditional 16-bit binary number to indicate the C-RNTI allocation, there is a 7-bit signaling burden. decrease.

After the user equipment sends the random access preamble, it can determine the corresponding C-RNTI group according to the random access preamble and the sending subframe, and according to the grouping relationship in Table 5. When the user equipment receives the After allocating the 9-bit binary number sent in the C-RNTI signaling to the user equipment, the C-RNTI allocated by the base station can be identified.

It should be noted that when the network side finds that the C-RNTI in a C-RNTI group is close to exhaustion, it will send C-RNTI reassignment signaling to some users who have already connected to the network to reassign Certain relatively idle groups, that is, C-RNTIs in groups whose C-RNTIs use less.

Example 2:

The following assumptions are given here:

- The preamble sequence of random access is sent every 10ms interval;

- There are 4 subframes in every 10ms interval that can send the random access preamble;

- There is one random access channel (frequency band with 1.25MHz bandwidth) in each subframe that can send random access preamble;

- There are 64 random access preamble sequences available to the system, 32 of which are used to initiate an asynchronous random access request requiring C-RNTI allocation (the user equipment does not have a C-RNTI).

According to the above assumptions, the C-RNTI spatial grouping of the system can be given as shown in Table 5 according to the method proposed by the present invention.

It can be seen from Table 5 that the 65536 C-RNTIs in the C-RNTI allocation space are divided into 32×4=128 according to the different random access preamble sequences sent by the user equipment and the different transmission subframes selected groups, and there are 65536/128=512 C-RNTIs in each group.

If both the base station and the user equipment know the above-mentioned C-RNTI grouping manner, they can perform C-RNTI allocation and identification.

First, the user equipment sends a random access preamble to the base station, and then the base station receives the random access preamble sent by the user equipment. According to the method of the present invention, the random access preamble sequence sent by the user equipment will correspond to a group of CRNTI. Taking Table 5 as an example, the combination of the random access preamble sent by the user equipment and the sent subframe will correspond to a CRNTI group. After the base station detects the random access preamble sent by the user equipment, it can base on the The selected random access preamble sequence and the subframe it sends can determine the C-RNTI group that should be allocated to it according to the grouping relationship in Table 5, and then select an unallocated C-RNTI group in the C-RNTI group. C-RNTI, and send the CRNTI assignment information in the response message of the random access preamble sequence to the user equipment, the CRNTI assignment information will be combined with the random access preamble sequence identification number information to indicate the CRNTI allocated by the base station . In this way, the response message of the random access preamble sequence will contain the following content:

Uplink resource assignment (UL resource assignment, UL RA), timing adjustment (TimingAdjustment, TA), random access preamble identification number (Random Access preambleID, RA_ID), and information indicating CRNTI combined with RA_ID.

In this embodiment, the combination of the RA_ID and the information indicating the CRNTI may be the sequence number of the allocated CRNTI in the CRNTI group, where the CRNTI group in this embodiment is the RA_ID and the transmission subframe of the random access preamble sequence The determined CRNTI packets are combined.

In this embodiment, the CRNTI group corresponding to the random access preamble contains only 29=512 CRNTIs, so the sequence number of the CRNTI allocated to the user equipment in the CRNTI group is a 9-bit binary number.

The 9-bit binary number corresponding to the sequence number of the C-RNTI in the group is sent to the user equipment in the C-RNTI allocation signaling to the user equipment, thereby realizing the use of 9-bit binary numbers to indicate the C-RNTI allocation, which is relatively Since the traditional 16-bit binary number is used to indicate the C-RNTI allocation, the signaling burden of 7 bits is reduced.

After sending the random access preamble, the user equipment can determine the corresponding C-RNTI group according to the random access preamble and the sending subframe, and according to the grouping relationship in Table 5. After that, the user equipment receives the response message of the random access preamble sent by the base station, and detects whether the message contains the RA_ID sent by it. If the RA_ID sent by it is detected, it can be determined that the response message includes the CRNTI assignment information allocated to the user equipment. Afterwards, the user equipment will detect the assignment information of the CRNTI sent by the base station in the message, and use this information together with the identification number of the random access preamble sent by it to determine the CRNTI assigned by the base station. Specifically, the user equipment determines the CRNTI grouping according to the combination of the RA_ID and the sending subframe of the preamble sequence and the corresponding relationship in Table 5, and then according to the CRNTI sent by the base station in the response message of the random access preamble sequence, the CRNTI grouping The sequence number (9-bit binary number) in can be combined to determine the CRNTI allocated by the base station.

It should be noted that when the network side finds that the C-RNTI in a C-RNTI group is close to exhaustion, it will send C-RNTI reassignment signaling to some users who have already connected to the network to reassign Certain relatively idle groups, that is, C-RNTIs in groups whose C-RNTIs use less.

Example 3:

The following assumptions are given here:

- There are 64 random access preamble sequences available to the system.

According to the above assumptions, the C-RNTI spatial grouping of the system can be given as shown in Table 7 according to the method proposed by the present invention.

Table 7 Grouping method of C-RNTI space in embodiment 3

It can be seen from Table 7 that the 65536 C-RNTIs in the C-RNTI allocation space are divided into 64 groups according to the different random access preamble sequences sent by the user equipment, and each group has 65536/64=1024 C-RNTI.

If both the base station and the user equipment know the above-mentioned C-RNTI grouping manner, they can perform C-RNTI allocation and identification.

First, the user equipment sends a random access preamble to the base station, and then the base station receives the random access preamble sent by the user equipment. According to the method of the present invention, the random access preamble sequence sent by the user equipment will correspond to a group of CRNTI. Taking Table 7 as an example, the random access preamble sent by the user equipment will correspond to a CRNTI group. After the base station detects the random access preamble sent by the user equipment, it can Sequence, according to the grouping relationship in Table 7, the C-RNTI group that should be allocated to it can be determined, and then a C-RNTI that has not been allocated can be selected in the C-RNTI group, and the random access to the user equipment CRNTI assignment information is sent in the preamble response message, and the CRNTI assignment information is combined with random access preamble sequence identification number information to indicate the CRNTI allocated by the base station. In this way, the response message of the random access preamble sequence will contain the following content:

Uplink resource assignment (UL resource assignment, UL RA), timing adjustment (TimingAdjustment, TA), random access preamble identification number (Random Access preambleID, RA_ID), and information indicating CRNTI combined with RA_ID.

In this embodiment, the combination of the RA_ID and the information indicating the CRNTI may be the sequence number of the allocated CRNTI in the CRNTI group, where the CRNTI group is the CRNTI group determined by the RA_ID in this embodiment.

In this embodiment, the CRNTI group corresponding to the random access preamble contains only 2 ¹⁰ =1024 CRNTIs, so the sequence number of the CRNTI allocated to the user equipment in the CRNTI group is a 10-bit binary number.

Assume that the sequence identification number of the random access preamble sent by the user equipment to the base station is 1, because there are 2 ⁶ =64 random access preambles in this embodiment, then the sequence identification number can be converted into a 6-bit binary number "000001", that is to say, the identification number RA_ID of the random access preamble sent by the user equipment = "000001".

After receiving the random access preamble sent by the user equipment, the base station determines that the CRNTI allocated to the user equipment should be in the CRNTI group 1 . Assuming that the base station selects C-RNTI 1022*64+1 (C-RNTI 65409) to allocate to the user equipment in Group 1, then the base station will include the following content in the random access response message sent to the user equipment:

- Uplink resource assignment (UL resource assignment, UL RA);

- Timing adjustment (Timing Adjustment, TA);

- the sequence number of the selected CRNTI assigned to the user equipment in the CRNTI group, namely "1111111110" (sequence number 1022);

-Random Access preamble ID (RA_ID), that is, "000001" (Random Access preamble ID 1).

In this way, the serial number "1111111110" of the indicated CRNTI in the CRNTI packet is used as the first 10 bits of the 16-bit CRNTI, and the identification number "000001" of the random access preamble is used as the last 6 bits of the 16-bit CRNTI. CRNTI "1111111110000001" (CRNTI 65409) to assign.

It should be noted that, in the above embodiment, the RA_ID is used to represent the last 6 bits of the CRNTI, and the sequence number in the CRNTI group represents the first 10 bits of the CRNTI. Using a similar method, given different grouping methods, RA_ID can also be used to represent the first 6 bits of the CRNTI, and the serial number in the CRNTI group can represent the last 10 bits of the CRNTI.

After the user equipment sends the random access preamble, it can determine the corresponding C-RNTI group according to the sent random access preamble and according to the grouping relationship in Table 7. After that, the user equipment receives the response message of the random access preamble sent by the base station, and detects whether the message contains the RA_ID sent by it. If the RA_ID sent by it is detected, it can be determined that the response message includes the CRNTI assignment information allocated to the user equipment. Afterwards, the user equipment will detect the assignment information of the CRNTI sent by the base station in the message, and use this information together with the identification number of the random access preamble sent by it to determine the CRNTI assigned by the base station. Specifically, the user equipment determines the CRNTI grouping according to the combination of RA_ID and the sending subframe of the preamble sequence and the corresponding relationship in Table 7, and then according to the CRNTI sent by the base station in the response message of the random access preamble sequence in the CRNTI grouping The serial number (10-bit binary number) in can be combined to determine the CRNTI allocated by the base station.

It should be noted that when the network side finds that the C-RNTI in a C-RNTI group is close to exhaustion, it will send C-RNTI reassignment signaling to some users who have already connected to the network to reassign Certain relatively idle groups, that is, C-RNTIs in groups whose C-RNTIs use less.

Secondly, an embodiment of the second implementation method of the C-RNTI allocation method proposed by the present invention is also given.

Example 4:

The following assumptions are given here:

- The preamble sequence of random access is sent every 10ms interval;

- There are 4 subframes in every 10ms interval that can send the random access preamble;

- There is one random access channel (frequency band with 1.25MHz bandwidth) in each subframe that can send random access preamble;

- There are 64 random access preamble sequences available to the system, 32 of which are used to initiate an asynchronous random access request requiring C-RNTI allocation (the user equipment does not have a C-RNTI).

According to the above assumptions, according to the method proposed by the present invention, firstly, in the total space containing 65536 C-RNTIs, C-RNTIs with sequence numbers from 1 to 1024 can be selected as special C-RNTI allocation spaces, and the C-RNTIs in this space - RNTI is a C-RNTI that can be used both during the random access process and after the random access process is completed. This special C-RNTI space can then be grouped as follows:

As can be seen from the above table, the 1024 C-RNTIs in the special C-RNTI allocation space are divided into 32×4=128 according to the different random access preamble sequences sent by the user equipment and the different selected sending subframes groups, and there are 1024/128=8 C-RNTIs in each group.

If both the base station and the user equipment have learned the above-mentioned C-RNTI grouping method, the allocation and identification of the C-RNTI can be performed:

After the base station detects the random access preamble sent by the user equipment, it can determine the random access preamble that should be allocated to it according to the random access preamble selected by the user equipment and the subframe it sends, and according to the grouping relationship in Table 6. C-RNTI grouping, then a C-RNTI that has not been allocated can be selected in the C-RNTI grouping, and sent to the user equipment in the response message of the random access preamble.

In this embodiment, the C-RNTI is transmitted to the user equipment in the control channel of layer 1/layer 2 (L1/L2), and the C-RNTI is used as the user equipment identification number (UE ID) to send the L1 /Identifier of the L2 control channel, and allocate a C-RNTI to the user equipment at the same time.

The sent C-RNTI can be XORed with the cyclic redundancy check bit, and then transmitted together (mask CRC). If the sent C-RNTI and CRC mask are transmitted together in the L1/L2 control channel, the format of the random access preamble sequence response message is shown in Figure 10. The response message to the random preamble transmitted in the L1/L2 control channel shall contain:

- uplink resource assignment;

- Timing adjustment;

-C-RNTI and mask bits of cyclic redundancy bits;

-other.

After the user equipment sends the random access preamble, it can determine the corresponding C-RNTI group according to the random access preamble and the sending subframe according to the grouping relationship in Table 6. When the user equipment receives the After the response message of the random preamble sequence, it is necessary to use the 8 C-RNTI contained in the determined packet to unmask the random preamble sequence response message in turn and perform CRC check, so as to identify the C-RNTI transmitted in the response message. C-RNTI, that is, obtain the C-RNTI allocated by the base station.

It should be noted that when the network side finds that the C-RNTI in a C-RNTI group is close to exhaustion, it will send C-RNTI reassignment signaling to some users who have already connected to the network to reassign The C-RNTI in the non-C-RNTI group space, thereby releasing the C-RNTI in the special space originally used, so as to avoid the exhaustion of the C-RNTI allocation of some groups in the C-RNTI special space.

The following is a hardware implementation block diagram of the base station implementing C-RNTI allocation in this embodiment, as shown in FIG. 11 .

First, the base station receives the random access preamble sent by the user equipment through the 1101 antenna and 1102 analog-to-digital conversion, and detects the random access preamble sent by the user equipment in the 1103 random access preamble detector, and converts it Send to 1104 controller.

In the 1105 random access preamble correspondence relationship module, the random access preamble sequence, the sending subframe, and the correspondence between the sent random access channel and the C-RNTI group will be stored. After the base station determines the random access preamble sent by the user equipment, and after sending the subframe and the sent random access channel, the controller 1104 will, according to the random access preamble stored in the random access preamble correspondence module in step 1105, Send subframes and the corresponding relationship between the sent random access channel and the C-RNTI group, determine the C-RNTI group that should be allocated to the user equipment, and select the appropriate C-RNTI assignment in the group, and assign the C-RNTI RNTI assignment information is sent to 1107 control information generator to generate control information assigned by C-RNTI, and passes through sending device, that is, 1108 channel coding/interleaving module, 1109 rate matching module, 1110 modulation module, 1111 control channel mapping module, 1112 OFDM modulation module, 1113 add cyclic prefix module, 1114 digital/analog conversion module, 1115 radio frequency transmitter module and 1101 antenna, send to user equipment.

Claims (14)

1. the method for a base station assigns cell-radio network temporary identifier C-RNTI comprises step:

A) subscriber equipment sends random access leader sequence to the base station;

B) response message of random access leader sequence is sent to subscriber equipment in the base station, and this response message comprises: the assignment information of ascending resource, and timing adjustment information, and make up the information of indication C-RNTI together with the random access leader sequence identifier;

C) subscriber equipment will send the message of L3 to network terminal;

D) network terminal can be sent the response of L3 message to subscriber equipment.

2. method according to claim 1 is characterized in that step b), and the information that said and random access leader sequence identifier makes up indication C-RNTI together is the sequence number of C-RNTI in specific C-RNTI divides into groups of being distributed.

3. method according to claim 1 is characterized in that step b), and said base station can also comprise the identifier of random access leader sequence to the response message of subscriber equipment transmission random access leader sequence.

4. method according to claim 2 is characterized in that the packet mode that said C-RNTI divides into groups is to be divided into groups as the C-RNTI packet space in whole C-RNTI space.

5. method according to claim 2 is characterized in that the packet mode that said C-RNTI divides into groups is that a sub-set in whole C-RNTI space is divided into groups as the C-RNTI packet space.

6. method according to claim 2 is characterized in that packet mode that said C-RNTI divides into groups is based on random access leader sequence the C-RNTI packet space is divided into groups.

7. method according to claim 2 is characterized in that said specific C-RNTI is grouped into the corresponding C-RNTI of the received random access leader sequence in base station and divides into groups.

8. method according to claim 2 is characterized in that the combination that packet mode that said C-RNTI divides into groups is based on the transmission subframe of random access leader sequence and random access leader sequence divides into groups.

9. method according to claim 2 is characterized in that said specific C-RNTI is grouped into the corresponding C-RNTI grouping of combination of the transmission subframe of received random access leader sequence in base station and random access leader sequence.

10. method according to claim 1 is characterized in that packet mode that said C-RNTI divides into groups is based on the transmission subframe of random access leader sequence, random access leader sequence and the combination of RACH is divided into groups.

11. method according to claim 2 is characterized in that said specific C-RNTI is grouped into the transmission subframe of the received random access leader sequence in base station, random access leader sequence and the corresponding C-RNTI of combination of RACH divides into groups.

12. method according to claim 1 is characterized in that step b), the response message of the random access leader sequence of said base station transmits transmits in the L1/L2 control channel.

13. method according to claim 1 is characterized in that step b), the response message of the random access leader sequence of said base station transmits transmits in descending shared data channel.

14. a base station equipment that is used to realize cell-radio network temporary identifier C-RNTI distribution comprises antenna, adds cyclic prefix module, the OFDM modulation module, and modulation module, the rate-matched module, chnnel coding/interleaving block, said base station equipment also comprises:

A) random access leader sequence detector is used for detecting the random access leader sequence that subscriber equipment sends, and identification is sent subframe and sent RACH;

B) controller; Be used for according to the C-RNTI grouping of the detected random access leader sequence of random access leader sequence detector, transmission subframe and transmission RACH with reference to the definite random access leader sequence response of being sent of the grouping corresponding relation of confirming in the C-RNTI grouping corresponding relation module; And in grouping, select suitable C-RNTI, pass to the control information maker afterwards and generate the control information that C-RNTI distributes;

C) dispensing device is used to send the control information that C-RNTI distributes.

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