Summary of the invention
The embodiment of the invention provides a kind of methods, devices and systems of expanding the coverage area, so that under the prerequisite that enlarges the eNB coverage, save running time-frequency resource.
A kind of method of expanding the coverage area, this method comprises:
Evolution base station eNB is in the frequency resource that uplink random access channel PRACH takies, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour's ascending pilot frequency subframe UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH, and allocation result is sent to UE;
Wherein, described time symbol comprises orthogonal frequency division multiplex OFDM symbol or the multiplexing SC-FDMA symbol of single carrier frequency division, and N is a natural number, and 1≤N≤7.
When described service subframe was the downlink business subframe, described time symbol was the OFDM symbol;
When described service subframe was the uplink service subframe, described time symbol was the SC-FDMA symbol.
Described N value is to determine according to the coverage requirement of eNB in advance.
This method also comprises: described eNB sets in advance the position of described UpPTS, perhaps, when carrying out the running time-frequency resource scheduling, according to the behaviour in service of running time-frequency resource, described UpPTS is arranged on the service subframe that is in close proximity to idle running time-frequency resource.
The position of described UpPTS is arranged between protection subframe GP and second the service subframe TS1, perhaps is arranged on the position of up-downgoing switching point, perhaps is arranged on after the TS1 and between any two service subframe before the up-downgoing switching point.
When described UpPTS is arranged on the service subframe that is in close proximity to idle running time-frequency resource, if described UpPTS is arranged on after this free time running time-frequency resource, then this there are back N the time symbol and the shared time-frequency resource allocating of UpPTS of the service subframe of idle running time-frequency resource to give PRACH; If described UpPTS is arranged on before this free time running time-frequency resource, then this there are the top n time symbol and the shared time-frequency resource allocating of UpPTS of the service subframe of idle running time-frequency resource to give PRACH.
Describedly allocation result is sent to UE comprise: give UE by the broadcast channel broadcasts among first service subframe TS0 described allocation result.
This method also comprises: after described UE receives described allocation result, send uplink pilot signal according to described allocation result on described PRACH.
A kind of system that expands the coverage area, this system comprises:
ENB, be used in the frequency resource that RPACH takies, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH, and allocation result is sent to UE;
UE is used to receive the allocation result that described eNB sends;
Wherein, described time symbol comprises OFDM symbol or SC-FDMA symbol, and N is a natural number, and 1≤N≤7.
A kind of eNB, this eNB comprises:
The PRACH allocation units, be used in the frequency resource that PRACH takies, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH;
The signaling transmitting element is used for the allocation result of described PRACH allocation units is sent to UE;
Wherein, described time symbol comprises OFDM symbol or SC-FDMA symbol, and N is a natural number, and 1≤N≤7.
This eNB also comprises: the positional information determining unit, be used to obtain the position of the described UpPTS that sets in advance, perhaps, when carrying out the running time-frequency resource scheduling, behaviour in service according to running time-frequency resource, described UpPTS is arranged on the service subframe that is in close proximity to idle running time-frequency resource, and the positional information of described UpPTS is offered described PRACH allocation units;
Described PRACH allocation units also are used to receive the positional information of described UpPTS, and carry out the operation that described distribution running time-frequency resource is given PRACH according to the positional information of described UpPTS.
This eNB also comprises: N value determining unit be used for determining described N value according to the coverage requirement of eNB, and the described N value that will determine offers described PRACH allocation units;
Described PRACH allocation units also are used to receive the N value that described N value determining unit provides, and carry out the operation that described distribution running time-frequency resource is given PRACH according to described N value.
A kind of UE, this UE comprises:
The allocation result acquiring unit, be used for from obtaining the allocation result that eNB sends, wherein, described allocation result is in the frequency resource that PRACH takies, and the time-frequency resource allocating that back N time symbol of next service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH;
The uplink pilot signal transmitting element is used for the allocation result obtained according to described allocation result acquiring unit, sends uplink pilot signal on PRACH; Wherein, described time symbol comprises OFDM symbol or SC-FDMA symbol, and N is a natural number, and 1≤N≤7.
As can be seen from the above technical solutions, the methods, devices and systems that the embodiment of the invention provides, in the frequency resource that takies at PRACH, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH, and allocation result is sent to UE.Make the running time-frequency resource of distributing to PRACH needn't take the time period of GP, this has just enlarged the coverage of eNB, and has reduced the interference of DwPTS to PRACH.And, compare with the method for expanding the coverage area in the prior art, only need take the part running time-frequency resource of N time symbol correspondence of service subframe, wherein, wherein, described time symbol comprises OFDM symbol or SC-FDMA symbol, the N value is a natural data, and 1≤N≤7 can't take whole running time-frequency resources of the whole time period of service subframe, thereby save running time-frequency resource.
Embodiment
In order to make the purpose, technical solutions and advantages of the present invention clearer, describe the present invention below in conjunction with the drawings and specific embodiments.
The main method of the embodiment of the invention comprises: in the frequency resource that PRACH takies, the time-frequency resource allocating of back N time symbol of next service subframe of top n time symbol in the last service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS to PRACH, and is sent to UE with allocation result by broadcast channel.Wherein, described time symbol is OFDM (OFDM) symbol or single carrier frequency division multiplexing (SC-FDMA) symbol, and N is a natural number, and 1≤N≤7.
Above-mentioned service subframe can be the uplink service subframe, also can be the downlink business subframe, and when above-mentioned service subframe was the downlink business subframe, the time symbol was the OFDM symbol; When above-mentioned service subframe was the uplink service subframe, described time symbol was the SC-FDMA symbol.
Wherein, the position of UpPTS can be of the prior art between GP and TS1, also can reset the position of UpPTS.According to the diverse location that UpPTS is provided with in radio frames, distribute PRACH that following several implementation can be arranged:
First kind of wireless frame structure figure that distributes PRACH that Fig. 4 provides for the embodiment of the invention, as shown in Figure 4, the position of UpPTS is still identical with position of the prior art, promptly between GP and TS1, in this embodiment, when TS1 is the uplink service subframe, in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that the top n SC-FDMA symbol among the TS1 and UpPTS take.That is to say that UE is in the frequency resource that PRACH takies, the shared running time-frequency resource of top n SC-FDMA symbol of TS1 is not used in the transmission business datum, but can be used to transmit ascending pilot frequency information.But other running time-frequency resource among the TS1, promptly in bandwidth range in other frequency resource except PRACH acquisition frequency resource, the running time-frequency resource that top n SC-FDMA symbol takies, and the running time-frequency resource that other SC-FDMA symbol takies in bandwidth range still can be used to send business datum.
Generally speaking; the coverage that the value of N is supported according to the eNB needs is determined; that is to say; radius according to the eNB coverage cell can calculate the UE transmission ascending pilot frequency needed time of information; this time is added that the guard time GT that prevents to disturb business datum and be provided with just can draw the time span that PRACH need take, and just can get access to the value of N according to this time span.Because a service subframe is made up of 9 time symbols, the length of a time symbol is 75us, and usually, when reaching the coverage of support 5km, the N value is got 1 demand that can satisfy this coverage.All can adopt this method to determine the value of N in following examples, repeat no more in the following description.
Fig. 5 a, can be arranged on UpPTS between TS1 and the TS2 shown in Fig. 5 a for second kind of wireless frame structure figure that distributes PRACH that the embodiment of the invention provides.In this embodiment, when TS2 is this service subframe, in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that the top n SC-FDMA symbol among the TS2 and UpPTS take.UE is in the frequency resource that PRACH takies, and the running time-frequency resource that the top n SC-FDMA symbol of TS2 takies is in order to sending business datum, but can be used to transmit uplink pilot signal, but other running time-frequency resource among the TS2 still can be used to send business datum.
In addition and since with UpPTS next-door neighbour's TS1 also be service subframe, so also the time-frequency resource allocating that back N SC-FDMA symbol among the TS1 and UpPST can be taken is to PRACH.Shown in Fig. 5 b.
If the up-downgoing switching point of this radio frames is arranged between TS3 and the TS4, so, UpPTS can also be provided with between TS3 and the TS4, or is arranged between TS2 and the TS3.When UpPTS is arranged between TS3 and the TS4, when TS3 is the uplink service subframe, when TS4 is the downlink business subframe, can be in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that back N SC-FDMA symbol among the TS3 and UpPTS take, at this moment, UE is in the frequency resource that PRACH takies, the shared running time-frequency resource of the top n SC-FDMA symbol of TS3 is in order to sending business datum, but can be used to transmit ascending pilot frequency information.Perhaps, when TS4 is the downlink business subframe, in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that the top n OFDM symbol among the TS4 and UpPTS take.At this moment, eNB is in the frequency resource that PRACH takies, and the shared running time-frequency resource of the top n OFDM symbol of TS4 is in order to sending business datum, but can be used to transmit descending pilot frequency information.When UpPTS is arranged between TS2 and the TS3, when TS2 and TS3 are the uplink service subframe, can be in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that back N SC-FDMA symbol among the TS2 and UpPTS take, or in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that the top n SC-FDMA symbol among the TS3 and UpPTS take.
In PRACH acquisition frequency resource, eNB gives PRACH with the time-frequency resource allocating that N time symbol in the service subframe takies, and just means that also this part running time-frequency resource in this service subframe can not be in order to send business datum.If this service subframe is the uplink service subframe, then UE does not use this part running time-frequency resource to send up business datum, correspondingly, during the data block of eNB in receiving the running time-frequency resource of this service subframe, after carrying out demodulation, the information of obtaining from the data block of this part running time-frequency resource correspondence of distributing to PRACH is ascending pilot frequency information, and the information of obtaining in the data block of other running time-frequency resource correspondence from this service subframe is business datum.If this service subframe is the downlink business subframe, then eNB does not use this part running time-frequency resource to send descending business datum, correspondingly, during the data block of UE in receiving the running time-frequency resource of this service subframe, after carrying out demodulation, the information of obtaining from the data block of this part running time-frequency resource correspondence of distributing to PRACH is descending pilot frequency information, and the information of obtaining in the data block of other running time-frequency resource correspondence from this service subframe is business datum.
Above-mentioned UpPTS position can set in advance, and for example, can predetermined fixed UpPTS be set between TS1 and TS2, and set in advance use in the frequency resource that PRACH takies, and the time-frequency resource allocating that back N SC-FDMA symbol among the TS1 takies is given PRACH.Also can be provided with according to the resource behaviour in service of reality by eNB, for example, eNB is when carrying out scheduling of resource, know that the business datum among the TS2 is less, be that idling-resource is arranged among the TS2, then the position of UpPTS can be arranged between TS1 and the TS2, and will be in the frequency resource that PRACH takies, the time-frequency resource allocating that the top n SC-FDMA symbol among the TS2 takies is given PRACH; Also the position of UpPTS can be arranged between TS2 and the TS3, and will be in the frequency resource that PRACH takies, the time-frequency resource allocating that back N SC-FDMA among the TS2 takies is given PRACH.
After eNB determines to distribute the mode of PRACH, can give UE by the broadcast channel broadcasts among the downlink business subframe TS0 with allocation result.After UE receives this allocation result that sends by TS0, in corresponding PRACH, send ascending pilot frequency information according to allocation result.For example, the allocation result that receives from broadcast channel as UE is during for the mode shown in Fig. 4, UE knows that the position of UpPTS is between GP and TS1, UE can transmit uplink pilot signal at the time point that finishes from GP to the time point of N the SC-FDMA sign-off of TS1 in the frequency resource scope of PRACH.Correspondingly, eNB is arranged on the time point that finishes from GP to the time point of N the SC-FDMA sign-off of TS1 with self ascending pilot frequency search window.When UE receives allocation result for the mode shown in Fig. 5 a from broadcast channel, UE knows that the position of UpPTS is between TS1 and TS2, the time point that this UE can finish at TS1 transmits uplink pilot signal between the time point of N the SC-FDMA sign-off of TS2 in the frequency resource scope of PRACH.Correspondingly, eNB is arranged on the time point that finishes from TS1 to the time point of N the SC-FDMA sign-off of TS2 with self ascending pilot frequency search window.Other situation does not in like manner repeat them here.
The system construction drawing of expanding the coverage area that Fig. 6 provides for the embodiment of the invention, as shown in Figure 6, this system can comprise: eNB 600 and UE 610.
ENB 600, be used in the frequency resource that RPACH takies, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH, and allocation result sent to UE 610, wherein, described time symbol is OFDM symbol or SC-FDMA symbol, and N is a natural number, and 1≤N≤7.
UE 610, are used to receive the allocation result that eNB 600 sends.
ENB 600 distributes running time-frequency resource can to adopt the mode described in the above-mentioned method of expanding the coverage area for the mode of PRACH.
Wherein, eNB 600 can send to UE 610 with allocation result by the broadcast channel among the TS0, and correspondingly, UE 610 receives this allocation result from this broadcast channel.
In addition, eNB 600, can also be used to set in advance the position of UpPTS, perhaps, when carrying out the running time-frequency resource scheduling, according to the behaviour in service of running time-frequency resource, UpPTS are arranged on the service subframe that is in close proximity to idle running time-frequency resource.
Wherein, eNB 600 can comprise: PRACH allocation units 601 and signaling transmitting element 602.
PRACH allocation units 601, be used in the frequency resource that PRACH takies, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH.
Signaling transmitting element 602 is used for the allocation result of PRACH allocation units 601 is sent to UE610.
In addition, this eNB 600 can also comprise: positional information determining unit 603, be used to obtain the position of the UpPTS that sets in advance, perhaps, when carrying out the running time-frequency resource scheduling, according to the behaviour in service of running time-frequency resource, this UpPTS is arranged on the service subframe that is in close proximity to idle running time-frequency resource, and the positional information of described UpPTS is offered PRACH allocation units 601.
PRACH allocation units 601 can also be used for the positional information of the UpPTS that receiving position information determining unit 603 provides, and carry out the operation that described distribution running time-frequency resource is given PRACH according to the positional information of this UpPTS.
This eNB 600 can also comprise: N value determining unit 604 is used for determining the N value according to the coverage requirement of eNB, and the N value of determining is offered PRACH allocation units 601.
PRACH allocation units 601 also are used to receive the N value that N value determining unit 604 provides, and carry out the operation that described distribution running time-frequency resource is given PRACH according to this N value.
In addition, the UE 610 in this system can comprise: allocation result acquiring unit 611 and uplink pilot signal transmitting element 612.
Allocation result acquiring unit 611, be used to obtain the allocation result that eNB 600 sends, wherein, this allocation result is in the frequency resource that PRACH takies, and the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH.
Uplink pilot signal transmitting element 612 is used for the allocation result obtained according to allocation result acquiring unit 611, sends uplink pilot signal on PRACH.
For example, if the allocation result that receives is that the position of UpPTS is between GP and TS1, in the frequency resource that PRACH takies, give PRACH with the time-frequency resource allocating that the top n SC-FDMA symbol among the TS1 and UpPTS take, this ascending pilot frequency transmitting element 612 then, then can in the frequency resource scope of PRACH, transmit uplink pilot signal at the time point that finishes from GP to the time point of N the SC-FDMA sign-off of TS1.
By above description as can be seen, the methods, devices and systems that the embodiment of the invention provides, in the frequency resource that takies at PRACH, the time-frequency resource allocating that back N time symbol of the last service subframe of top n time symbol in next service subframe of next-door neighbour UpPTS or next-door neighbour UpPTS and UpPTS is shared is to PRACH, and allocation result is sent to UE by broadcast channel.Make the running time-frequency resource of distributing to PRACH needn't take the time period of GP, this has just enlarged the coverage of eNB, and has avoided the interference of DwPTS to PRACH.And, compare with the method for expanding the coverage area in the prior art, only need take the part running time-frequency resource in N the time symbol of service subframe, wherein, the time symbol can be OFDM symbol or SC-FDMA symbol, and N is a natural number, and 1≤N≤7, can't take all running time-frequency resources in whole time period of service subframe, thereby save running time-frequency resource.
In addition, the embodiment of the invention can be determined concrete N value according to the coverage requirement of reality, thereby reduces the N value and satisfy the demands, thereby adjust the N value more neatly under the situation of large coverage very not needing, and can farthest save running time-frequency resource.
In addition, the embodiment of the invention can also be according to the operating position of actual running time-frequency resource in the position that UpPTS is set, it is arranged on the service subframe that is in close proximity to idle running time-frequency resource, and utilize this to have the service subframe of idle running time-frequency resource to distribute to PRACH, thereby the business datum in the minimizing service subframe more preferably enlarges the coverage of eNB to the interference of PRACH.
The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being made, is equal to replacement, improvement etc., all should be included within the scope of protection of the invention.