CN102387600B - Random access method for broadband trunking communication system - Google Patents

Abstract

The invention provides a random access method for a broadband trunking communication system, which is specific to user equipment (UE) supporting a single subband working mode. The method comprises the following steps that: the UE transmits a random access preamble code, directly skips to an ordinary subband mapped by a physical random access channel (PRACH) resource where the transmitted random access preamble code is positioned, and monitors a random access response; and an evolved Node B (eNB) receives the random access preamble code transmitted by the UE, and transmits a random access response to the UE on the ordinary subband mapped by the PRACH resource where the transmitted random access Preamble code is positioned. According to the method, the UE supporting the single subband working mode can normally complete a random access process by using the mapping relation between the PRACH resource where the random access preamble code is positioned and the ordinary subband where the random access response is positioned.

Description

The method of random access in the trunked communication system of a kind of broadband

Technical field

The present invention relates to wireless communication technology field, particularly the method for random access in the trunked communication system of a kind of broadband.

Background technology

In the trunked communication system of broadband, system available bandwidth is divided into a plurality of continuous or discrete subbands, adopts OFDM (OFDM) technical transmission on each subband.According to function, by each sub-band division, be synchronous subband and common subband conventionally.Synchronous subband is for the synchronous and broadcast channel of up-downgoing, wherein uplink special time slot (UpPTS) and the sub-frame of uplink in synchronous subband can be used as Physical Random Access Channel (PRACH) resource, allows user to access at random in PRACH resource.Common subband is for the transmission of regular traffic.

Random access technology is an important technology of media access control in communication system.In the broadband trunked communication system based on time-division Long Term Evolution (TD-LTE) technology, random access is the access procedure of subscriber equipment (UE) before network service, is mainly used in the objects such as initial access, RRC connection reconstruction and switching of UE.

Fig. 1 is the flow chart of random access procedure in existing LTE system, and each UE adopts the mode of competition to access at random, mainly comprises following four steps:

Step 101:UE sends random access pilot tone (Preamble code) in up PRACH, is designated as Msg1.

Step 102: base station (eNB) so that this UE is carried out to uplink authorization, is designated as Msg2 at the upper accidental access response producing to this UE transmission MAC layer of downlink sharied signal channel (DL-SCH).

Step 103:UE receives after accidental access response, at uplink shared channel (UL-SCH), above transmits scheduling request information, and the schedule information that comprises uplink first in this scheduling request information, is designated as MSG3.

Step 104:eNB receives after MSG3, and on DL-SCH channel, to this UE transmission competition decision message, the competition that comprises UE in this competition decision message resolution sign, is designated as Msg4.

So far, UE completes the random access procedure of competition.

In order to reduce costs and implementation complexity, make UE support list band mode of operation, UE receiver bandwidth needs not to be whole system bandwidth, and UE only supports to receive single subband needn't receive whole subbands.Like this, reduce the requirement to UE receiver bandwidth, also reduced the demand of system to hardware capabilities.This change causes existing LTE random access procedure directly not apply, otherwise the UE of list band mode of operation cannot be known the transmission subband of MSG2, cannot normally receive Msg2, and this will cause UE cannot complete random access procedure.

Summary of the invention

In view of this, the invention provides the method for random access in the trunked communication system of a kind of broadband, so that support the UE of list band mode of operation can normally complete random access procedure.

A method for random access in the trunked communication system of broadband, the method is for the user equipment (UE) of supporting list band mode of operation, and the method comprises:

Described UE selects PRACH resource to send random access Preamble code to base station eNB;

Described UE is according to default mapping relations, jumps on the common subband that described PRACH resource is mapped to, and monitors the accidental access response that described eNB sends to described UE.

Wherein, described UE selects PRACH resource specifically to comprise to the random access of eNB transmission Preamble code:

Described UE, in continuous m radio frames, selects a PRACH resource to send the random access Preamble code of current area according to random function from synchronous subband; Wherein, m is greater than 1 integer, and described random function meets the selecteed probability of each PRACH resource in described continuous m radio frames and equates.

Further, the method can also comprise: if described UE successfully receives described accidental access response in setting-up time,, according to the uplink authorization information of carrying in described accidental access response, on authorized subband, to described eNB, send scheduling request information;

Otherwise determine this random access failure, again go to described UE and select PRACH resource to send random access Preamble code to eNB.

Wherein, if the information matches of the RA-RNTI that the accidental access response that UE listens in setting-up time comprises and described PRACH resource, and the shift of the random access Preamble code that the Preamble code shift comprising sign sends with described UE identifies consistent, described UE determines and successfully receives the accidental access response that sends to this UE.

More preferably, if the RA-RNTI that described accidental access response comprises meets RA-RNTI=64+slot_id+7*f_id, the RA-RNTI that definite described accidental access response comprises and the information matches of described PRACH resource; Wherein, slot_id is the time slot index at described PRACH resource place, and f_id is the synchronous subband index at described PRACH resource place.

Further, in described scheduling request information, comprise competition resolution sign.

If described UE received at competition judgement timer the competition decision message that comprises described competition resolution sign that eNB returns then, determine that this accesses successfully at random; Otherwise this random access failure, again goes to described UE and selects PRACH resource to send random access Preamble code to eNB.

More preferably, described default mapping relations are:

$\mathrm{SN}=\left\{\begin{array}{cc}(\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}(N_i/7)\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7=0\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}{N}_i\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7\≠0\end{array}\right.;$ Wherein, SN is the sub-reel number of the common subband at accidental access response place, SFN _msg1for the System Frame Number of described PRACH resource, slot_id is the time slot index at described PRACH resource place, N _ithe number of common subband in being one bunch.

A method for random access in bandwidth trunked communication system, the method is for the user equipment (UE) of supporting list band mode of operation, and the method comprises:

Base station eNB receives after the random access Preamble code of described UE transmission, according to default mapping relations, on the common subband being mapped to, to described UE, sends accidental access response in the described random PRACH resource that accesses Preamble code place.

Wherein, in described accidental access response, comprise: with the RA-RNTI of the information matches of the PRACH resource at described random access Preamble code place, identify consistent Preamble code shift sign and indicate described UE to send the uplink authorization information of scheduling request information on authorized subband with the shift of described random access Preamble code.

More preferably, with the RA-RNTI of the information matches of the PRACH resource at described random access Preamble code place be:

RA-RNTI=64+slot_id+7*f_id, wherein, slot_id is the time slot index at described PRACH resource place, f_id is the synchronous subband index at described PRACH resource place.

Further, the method also comprises: described eNB, after receiving the scheduling request information that comprises competition resolution sign that described UE sends, replys the competition decision message that comprises described competition resolution sign to described UE.

More preferably, described default mapping relations are:

$\mathrm{SN}=\left\{\begin{array}{cc}(\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}(N_i/7)\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7=0\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}{N}_i\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7\≠0\end{array}\right.;$ Wherein, SN is the sub-reel number of the common subband at accidental access response place, SFN _msg1for the System Frame Number of described PRACH resource, slot_id is the time slot index at described PRACH resource place, N _ithe number of common subband in being one bunch.

As can be seen from the above technical solutions, UE, after sending random access Preamble code, directly jumps to and sends on the common subband that the PRACH resource at access Preamble code place is mapped at random, monitors accidental access response.Equally, eNB, after receiving the random access Preamble code of UE transmission, to this UE sends accidental access response on the common subband being mapped in this random PRACH resource that accesses Preamble code place.That is to say, utilize the mapping relations between the random access PRACH resource at Preamble code place and the common subband at accidental access response place, guaranteed to support that the UE of list band mode of operation can normally complete random access procedure.

Accompanying drawing explanation

Fig. 1 is the flow chart of random access procedure in existing LTE system;

Fig. 2 is main method flow chart provided by the invention;

The subband distribution map of the electric power load monitoring and control communication network that Fig. 3 provides for the embodiment of the present invention.

Embodiment

In order to make the object, technical solutions and advantages of the present invention clearer, below in conjunction with the drawings and specific embodiments, describe the present invention.

Method provided by the invention can as shown in Figure 2, mainly comprise the following steps:

Step 201:UE selects PRACH resource to send random access Preamble code to eNB.

The Preamble code that UE adopts is known, owing to only having a Preamble code at whole network, interference for fear of adjacent cell, Preamble sequence in Yi Ge community adopts same cyclic shift, if the Preamble code of other cyclic shifts detected in eNB community, can be judged as the interference signal of neighbor cell.Shift index indication Preamble code in Preamble code carries out the information of cyclic shift, and it is that UE obtains by broadcast in cell search process.That is to say, UE adopts the Preamble sequence of appointment to send in the PRACH resource of selecting.

In order to reduce the collision problem of the random access of competition, UE can be in m radio frames continuously, according to random function from synchronous subband can with PRACH resource in select a PRACH resource to send random access Preamble code.Wherein, m is greater than 1 integer.For example, radio frames n+1 adjacent after the radio frames n at current time place is to radio frames n+m, according to random function, from synchronous subband, in available PRACH resource, select a PRACH resource, in certain hour length, equiprobability is selected the PRACH sign resources on synchronous subband.Wherein, random function meets the selected probability of each PRACH resource and equates, thereby reduces to compete the collision probability of random access.

UE selects can be represented by the time slot index slot_id of synchronous subband index f_id, System Frame Number and PRACH resource for sending the PRACH resource information of random access Preamble code.Wherein synchronous subband index f_id can be mapped to the sub-reel number of synchronous subband, and sub-reel number is all synchronous subbands and the common subband numbering after according to frequency domain ascending order or descending sort.System Frame Number is for sending the System Frame Number (SFN) of the radio frames of random access Preamble code.The time slot index slot_id of PRACH resource can be mapped to the time interval resource at PRACH resource place, and mapping relations can be as shown in table 1.

Table 1

In addition, UE can adopt default random access Preamble code transmitted power to send random access Preamble code.

Step 202:eNB determines that UE sends the common subband that the random PRACH resource mapping that accesses Preamble code place arrives, and sends accidental access response to UE on this common subband.

Correspondingly, UE after sending random access Preamble code, jump to the PRACH resource mapping that sends random access Preamble code place to common subband on, monitor the accidental access response that eNB sends to this UE.

In the accidental access response that base station sends, comprise random access radio network and identify sign (RA-RNTI) temporarily, this RA-RNTI is determined by the PRACH resource that sends random access Preamble code, for example, can adopt following formula (1) to determine:

RA-RNTI＝64+slot_id+7*f_id (1)

In conventional wireless frame structure, 0 <=slot_id <, 7,0 <=f_id < K, the number that K is synchronous subband.

Correspondingly, UE, when monitoring accidental access response, listens to and comprises the RA-RNTI sign corresponding with the PRACH resource that sends random access Preamble code, determines and sends to this UE.

In addition, the common subband that the common subband that base station transmission accidental access response is used and UE receiving random access response jump to is to be determined by information and the mapping relations between common subband of the PRACH resource setting in advance, the common subband that definite information that sends the PRACH resource of the random Preamble of access code is mapped to.Wherein, the information of PRACH resource can comprise: synchronous subband index, radio frames index and time slot index.

Mapping relations between the common subband of the information of PRACH resource and accidental access response place can adopt following formula:

$\mathrm{SN}=\left\{\begin{array}{cc}(\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}(N_i/7)\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7=0\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}{N}_i\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7\&NotEqual;0\end{array}\right.---\left(2\right)$

Wherein, SN is the sub-reel number of the common subband at accidental access response place, SFN _msg1for sending the System Frame Number of random access Preamble code, N _ithe number of common subband in being one bunch.

In one bunch, comprise a synchronous subband and seven or seven above common subbands, because the position of synchronous subband is not fixed, SN can be in one bunch except desynchronizing subband, common subband in frequency domain with the relatively common sub-reel number of ascending order or descending.According to place, bunch map out with this relative common sub-reel number of SN the reel number of monitoring accidental access response place.

In addition, the accidental access response window that UE monitors accidental access response originates in the transmission next radio frames of the radio frames of access Preamble code at random, and length can be m radio frames.

Once UE successfully receives the accidental access response that sends to this UE, stop monitoring accidental access response transmission.Wherein, if the shift sign of the random access Preamble code that the Preamble code shift comprising in the accidental access response that UE receives in setting-up time sign sends in step 201 with UE is consistent, determines and successfully receive the accidental access response that sends to this UE; If do not receive the accidental access response that sends to this UE in setting-up time, or the Preamble code shift that the accidental access response that sends to this UE receiving comprises sign is inconsistent with the shift sign of the random access Preamble code that UE sends in step 201, determine and successfully do not receive the accidental access response that sends to this UE, this random access failure.

Step 203:UE successfully receives after the accidental access response that sends to this UE, to eNB, sends scheduling request information.

UE can determine according to the uplink authorization information of carrying in accidental access response the up sub-band information that UE is authorized, authorized up sub-reel number for example, and send scheduling request information on authorized subband, i.e. Msg3 message.

In addition, in random access procedure, mixed automatic retransfer request (HARQ) is supported in the transmission of Msg3 message, and wherein HARQ maximum retransmission is notified to UE by high level.

Step 204:eNB receives after the scheduling request information of UE, the judgement that is at war with, and return to competition decision message to UE.

In the scheduling request information that UE sends in step 203, comprise competition resolution sign, if eNB successfully receives the scheduling request information of UE, in the competition decision message of returning to UE, comprise this competition resolution sign.

If UE received at competition judgement timer the competition decision message that eNB returns then, and the competition comprising in this competition decision message resolution sign and this UE send to the competition of eNB to resolve to identify consistent, and this accesses successfully at random; Otherwise this random access failure.

For convenient, understand, the random access procedure competed in power communication system of take is below elaborated to said method as example.

The subband distribution map of the electric power load monitoring and control communication network that Fig. 3 provides for the embodiment of the present invention, in this networking, each community has 40 subbands, be divided into three bunches, in each bunch, have 1 synchronous subband, other be common subband, as shown in Figure 3, the subband of filling shade is synchronous subband, and the subband filling in the blanks is common subband.Whole network only has a Preamble code, and for fear of the interference of adjacent cell, the Preamble sequence in Yi Ge community only adopts same cyclic shift, and the Preamble code of other cyclic shift is considered as the interference signal of neighbor cell.If UE supports list band model in this networking, the random access procedure of its competition is as follows:

First performing step 201, UE selects PRACH resource to send random access Preamble code to eNB at random.

This random access Preamble code adopts the Preamble sequence of community appointment, and the information of the cyclic shift that the indicated Preamble code of shift index wherein carries out is that UE obtains by broadcast in cell search process.

In order to reduce the collision problem of the random access of competition, in this example, UE is in can be after the radio frames n at current time place adjacent two continuous radio frames n+1 and n+2, according to random function, from synchronous subband, in available PRACH resource, select a PRACH resource, i.e. the random PRACH resource of selecting on synchronous subband in certain hour length equiprobably.Wherein, random function meets the selected probability of each PRACH resource and equates, thereby reduces to compete the collision probability of random access.

The information of the PRACH resource that UE selects is represented by the time slot index slot_id of synchronous subband index f_id, System Frame Number and PRACH resource.Wherein, in this example, synchronous number of sub-bands is 3, and the sub-reel number of the synchronous subband that synchronous subband index is mapped to can be as shown in table 2.In this example, System Frame Number is for sending the System Frame Number of the radio frames of random access preamble code.The time slot index slot_id of PRACH resource can be as shown in table 1.

Table 2

Like this, UE is used default random access preamble code transmitted power and the random access preamble sequence of community appointment to transmit in the PRACH resource of selecting.

Then perform step 202, base station determines that UE sends the common subband that the random PRACH resource mapping that accesses Preamble code place arrives, and sends accidental access response message to UE on this common subband.

Correspondingly, UE sends after random access Preamble code, jump to the PRACH resource mapping that sends random access Preamble code place to common subband on, monitor the accidental access response that base station sends to this UE.

Wherein, the RA-RNTI sign comprising in the accidental access response that base station sends can adopt above-mentioned formula (1) to determine, does not repeat them here.UE, when monitoring accidental access response, listens to and comprises the RA-RNTI sign corresponding with the PRACH resource that sends random access Preamble code, determines and sends to this UE.

The accidental access response window that UE monitors accidental access response originates in the transmission next radio frames of the radio frames of access Preamble code at random, and length is 2 radio frames.

Base station send common subband that accidental access response uses and the frame-skipping of UE receiving random access response institute to common subband be definite with the mapping relations between common subband by the information of the PRACH resource setting in advance.In this example, the mapping relations of employing can be:

$\mathrm{SN}=\left\{\begin{array}{cc}\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}2\right)*7& f\_\mathrm{id}=\mathrm{0,2}\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}9\right)*7)\mathrm{mod}9,& f\_\mathrm{id}=1\end{array}\right.---\left(3\right)$

Wherein, SN is the sub-reel number that transmission accesses the common subband that the PRACH resource of Preamble code is mapped at random, SFN _msg1for sending the System Frame Number of random access Preamble code.

Because the position of synchronous subband is not fixed, SN can be except desynchronizing subband in one bunch, the relatively common sub-reel number that common subband is arranged with ascending order in frequency domain, according to place bunch with this relative common sub-reel number of SN, can map out the sub-reel number of monitoring accidental access response transmission place.

When UE successfully receives the accidental access response that sends to this UE, stop monitoring accidental access response transmission.Wherein, if the shift sign of the random access Preamble code that the Preamble code shift comprising in the accidental access response that UE receives in setting-up time sign sends with UE is consistent, determines and successfully receive the accidental access response that sends to this UE; If do not receive the accidental access response that sends to this UE in setting-up time, or the Preamble code shift that the accidental access response that sends to this UE receiving comprises sign is inconsistent with the shift sign of the random access Preamble code that UE sends, and determines and does not successfully receive the accidental access response that sends to this UE.

Afterwards, execution step 203, UE sends scheduling request information to eNB.

When UE receives accidental access response in setting-up time, and the shift sign of the random access Preamble code that the Preamble code shift comprising in this accidental access response sign sends with UE is consistent, UE determines according to the uplink authorization information of carrying in accidental access response the up sub-band information that UE is authorized, and on authorized subband, send scheduling request information, i.e. Msg3 message.

HARQ process is supported in the transmission of this Msg3 message, and wherein HARQ maximum retransmission is notified by high level.Particularly, UE sends after Msg3 message, if received the ACK response message that eNB replys before HARQ timer expires, UE will stop the re-transmission of Msg3 message, waits for the competition resolution message of eNB.If UE received the NACK response message of eNB before HARQ timer expires, UE will carry out the re-transmission of Msg3 message on authorized ground subband.When number of retransmissions reaches maximum HARQ number of retransmissions, UE does not still receive the ACK response message that eNB returns, and UE thinks that this random access procedure is failed; If in retransmission processes, UE has received the ACK response message of eNB, and UE will stop retransmitting, and waits for the competition resolution message of eNB.

Finally perform step 204, eNB and return to competition decision message to UE.

After eNB successfully receives Msg3 message, the competition resolution sign that this UE sends in Msg3 message will be carried in the competition decision message returning.

If UE received at competition judgement timer the competition decision message that eNB returns then, and the competition comprising in this competition decision message resolution sign and this UE send to the competition of eNB to resolve to identify consistent, and this accesses successfully at random; Otherwise this random access failure.

By above description, can be found out, method provided by the invention can possess following advantage:

1) UE, after sending random access Preamble code, directly jumps to and sends on the common subband that the PRACH resource at access Preamble code place is mapped at random, monitors accidental access response.Equally, eNB, after receiving the random access Preamble code of UE transmission, to this UE sends accidental access response on the common subband being mapped in this random PRACH resource that accesses Preamble code place.That is to say, utilize the mapping relations between the random access PRACH resource at Preamble code place and the common subband at accidental access response place, guaranteed to support that the UE of list band mode of operation can normally complete random access procedure, reduced signaling consumption.

2) UE is after receiving accidental access response, utilize uplink authorization acquisition of information in accidental access response to the information of residence sub-band, resident on authorized subband and send scheduling request information and receive competition decision message, thus signaling consumption and access delay reduced.

The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of making, be equal to replacement, improvement etc., within all should being included in the scope of protection of the invention.

Claims (10)

1. a method for random access in the trunked communication system of broadband, the method, for the user equipment (UE) of supporting list band mode of operation, is characterized in that, the method comprises:

Described UE selects Physical Random Access Channel PRACH resource to send random access pilot tone Preamble code to base station eNB;

Described UE is according to default mapping relations, jumps on the common subband that described PRACH resource is mapped to, and monitors the accidental access response that described eNB sends to described UE;

Described default mapping relations are:

$\mathrm{SN}=\left\{\begin{array}{cc}(\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}(N_i/7)\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7=0\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}{N}_i\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7\&NotEqual;0\end{array}\right.;$ Wherein, SN is the sub-reel number of the common subband at accidental access response place, SFN _msg1for the System Frame Number of described PRACH resource, slot_id is the time slot index at described PRACH resource place, N _ithe number of common subband in being one bunch.

2. method according to claim 1, is characterized in that, described UE selects PRACH resource specifically to comprise to the random access of eNB transmission Preamble code:

Described UE, in continuous m radio frames, selects a PRACH resource to send the random access Preamble code of current area according to random function from synchronous subband; Wherein, m is greater than 1 integer, and described random function meets the selecteed probability of each PRACH resource in described continuous m radio frames and equates.

3. method according to claim 1 and 2, it is characterized in that, the method also comprises: if described UE successfully receives described accidental access response in setting-up time,, according to the uplink authorization information of carrying in described accidental access response, on authorized subband, to described eNB, send scheduling request information;

Otherwise determine this random access failure, again go to described UE and select PRACH resource to send random access Preamble code to eNB.

4. method according to claim 3, it is characterized in that, if the random access radio network that the accidental access response that UE listens in setting-up time comprises is identified the information matches of sign RA-RNTI and described PRACH resource temporarily, and the shift of the random access Preamble code that the Preamble code shift comprising sign sends with described UE identifies consistent, described UE determines and successfully receives the accidental access response that sends to this UE.

5. method according to claim 4, it is characterized in that, if the RA-RNTI that described accidental access response comprises meets RA-RNTI=64+slot_id+7*f_id, the RA-RNTI that definite described accidental access response comprises and the information matches of described PRACH resource; Wherein, slot_id is the time slot index at described PRACH resource place, and f_id is the synchronous subband index at described PRACH resource place.

6. method according to claim 3, is characterized in that, comprises competition resolution sign in described scheduling request information;

If described UE received at competition judgement timer the competition decision message that comprises described competition resolution sign that eNB returns then, determine that this accesses successfully at random; Otherwise this random access failure, again goes to described UE and selects PRACH resource to send random access Preamble code to eNB.

7. a method for random access in bandwidth trunked communication system, the method, for the user equipment (UE) of supporting list band mode of operation, is characterized in that, the method comprises:

Base station eNB receives after the random access pilot tone Preamble code of described UE transmission, according to default mapping relations, on the common subband being mapped in the described random Physical Random Access Channel PRACH resource that accesses Preamble code place, to described UE, send accidental access response;

Described default mapping relations are:

$\mathrm{SN}=\left\{\begin{array}{cc}(\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}(N_i/7)\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7=0\\ (\mathrm{slot}\_\mathrm{id}+\left({\mathrm{SFN}}_{\mathrm{Msg}1}\mathrm{mod}{N}_i\right)*7)\mathrm{mod}{N}_i,& N_i\mathrm{mod}7\&NotEqual;0\end{array}\right.;$ Wherein, SN is the sub-reel number of the common subband at accidental access response place, SFN _msg1for the System Frame Number of described PRACH resource, slot_id is the time slot index at described PRACH resource place, N _ithe number of common subband in being one bunch.

8. method according to claim 7, it is characterized in that, in described accidental access response, comprise: identify sign RA-RNTI temporarily, identify consistent Preamble code shift sign and indicate described UE on authorized subband, to send the uplink authorization information of scheduling request information with the shift of described random access Preamble code with the random access radio network of the information matches of the PRACH resource at described random access Preamble code place.

9. method according to claim 8, is characterized in that, with the RA-RNTI of the information matches of the PRACH resource at described random access Preamble code place is:

RA-RNTI=64+slot_id+7*f_id, wherein, slot_id is the time slot index at described PRACH resource place, f_id is the synchronous subband index at described PRACH resource place.

10. according to the method described in claim 7,8 or 9, it is characterized in that, the method also comprises: described eNB, after receiving the scheduling request information that comprises competition resolution sign that described UE sends, replys the competition decision message that comprises described competition resolution sign to described UE.