CN101677304B - Collocation method of downlink common pilot frequency - Google Patents

Abstract

The invention discloses a collocation method of downlink common pilot frequency, comprising the following steps: collocating downlink common pilot frequency patterns to the 8-antenna transmission mode of a cell by a network side, wherein, the quantity of the pilot frequency respectively collocated to the unit resource block on the fifth to eighth antenna ports is less than or equal to the quantity of the pilot frequency collocated to the unit resource blocks on the third to fourth antenna ports; and setting the downlink common pilot frequency pattern in a base station to which the cell belongs and the user equipment (UE) of the cell. The invention can realize the downlink common pilot frequency collocation of the 8-antenna transmission mode, has low pay expenses on the pilot frequency, and can improve the system efficiency.

Description

A kind of collocation method of down public guide frequency

Technical field

The present invention relates to physical layer multi-antenna technology field, particularly a kind of collocation method of down public guide frequency.

Background technology

Many input and output (MIMO) technology is played an important role in communication system of new generation as the important raising transmission quality and the physical layer multi-antenna technology of efficient.For example, Long Term Evolution (LTE) system just supports transmit diversity, space multiplexing technique and beam forming (Beam forming, BF) etc. multiple MIMO technology.

The LTE that strengthens (LTE-Advanced, LTE-A) the clearly following demand of system: satisfy 6 frequency ranges of adaptation, in addition its peak rate under be about to greater than 1Gbps, up greater than 500Mbps.Aspect peaks spectrum efficient, LTE-A has satisfied descending: 30bps/Hz, and up: 15bps/Hz.Aspect IP-based voice (VoIP) volume of business, LTE-Advanced can satisfy the demand greater than 300 parallel VoIP/5MHz, and the forward and backward compatibility of support and LTE system.

This shows: an important directions of LTE-A system is to further optimization indoor, that local covers, low speed moves.Therefore, numerous manufacturers have proposed 8 * 8 antennas (i.e. 8 antennas) downlink transfer scheme, solve peaks spectrum efficiency under this scene.Correspondingly, the descending pilot frequency allocation problem of 8 * 8 antenna transmission mode becomes one of relevant with it research focus.

Pilot tone be mainly used in to Physical Downlink Control Channel (Physical Downlink Control Channel, PDCCH), the demodulation of PBCH, DBCH, PMCH etc., channel quality information (CQI) estimate, non-excipient user's channel estimating, the measurement when switch the sub-district etc.The LTE system is that unit sends down public guide frequency with the Resource Block, and each Resource Block comprises 1 time slot on time domain, on frequency domain, comprise 12 number of sub-carrier.All Resource Block of LTE system cover the whole system bandwidth on frequency domain.Below as do not add explanation, all adopting regular circulation prefix (CP) with system is example as the intersymbol protection of OFDM (OFDM) scene at interval, and the configuration mode of down public guide frequency is described.Can obtain the configuration mode of corresponding downstream public guide frequency according to the situation of conventional CP for expansion CP.Show the configuration mode of the down public guide frequency of 1 * 1 antenna in the LTE system, 2 * 2 antennas and 4 * 4 antennas respectively like Fig. 1 to Fig. 3.R0/R1/R2/R3 representes the down public guide frequency ofantenna port 0/1/2/3 respectively among the figure.Fig. 1 shows two Resource Block that the single antenna port sends, and the time slot of one of them Resource Block is the even number time slot, and the time slot of another Resource Block is the odd number time slot.Comprise the subcarrier of 12 different frequencies on vertical (being frequency domain) of a Resource Block, use k=0,1,2...13 representes the frequency resource that each subcarrier is corresponding; Transversely (being time domain) comprises 7 OFDM symbols, uses 1=0, and 1...6 representes the time-domain resource that each OFDM symbol is corresponding.Each OFDM symbol is represented with a lattice.4 down public guide frequencies that distributed in each Resource Block, blank grid then is the resource element of traffic load.The implication of diagramatic content is identical with Fig. 1 among Fig. 2 and Fig. 3.

Can find out that from Fig. 1 to Fig. 3 down public guide frequency is evenly distributed on the whole Resource Block.Wherein, the down public guide frequency of antenna port R0/R1 is mapped in the 1st, 5, on 8,12 OFDM symbols, whenever inserts a down public guide frequency at a distance from 6 number of sub-carrier on the frequency domain.In order to guarantee the closeer distribution of frequency domain up-downgoing public guide frequency, the reference symbol on the 5th, 12 symbol with respect to the 1st, 8 symbol offset 3 number of sub-carrier.The down public guide frequency of antenna port R2/R3 is mapped on the 2nd, 9 symbol, whenever inserts a down public guide frequency at a distance from 6 number of sub-carrier on the frequency domain.In order to guarantee the closeer distribution of frequency domain up-downgoing public guide frequency, the reference symbol on the 9th symbol with respect to the 2nd symbol offset 3 number of sub-carrier.Down public guide frequency relativity shift 3 number of sub-carrier that the different antennae port shines upon on same symbol.Each antenna port is distributed on the resource of other antenna port reference signals and can not be transmitted any information except needs transmit the down public guide frequency resource of the port.Therefore, the down public guide frequency expense is linear growth along with the increase of antenna number.In Fig. 1, in the descending sub frame, except down public guide frequency remaining all be Resource Block, the reference symbol expense is minimum to be 4.8%; And among Fig. 2 in the descending sub frame ofantenna port 0 emission, except self down public guide frequency R0, also to reserve the corresponding OFDM symbol of down public guide frequency R1 ofantenna port 1, the down public guide frequency expense is 9.5%.And 4 antenna ports shown in Figure 3 when configuration, the expense relevant with pilot tone has 12 resource elements on each Resource Block, and 14.3% down public guide frequency expense is promptly arranged in each Resource Block.

At present, propose to be directed against the down public guide frequency allocation plan of 8 * 8 antenna transmission mode in the LTE-A system as yet.

Summary of the invention

In view of this, the embodiment of the invention proposes a kind of configuration method for downlink public pilot frequency of 8 antenna transmission mode.Particularly, this method comprises:

Network side is 8 antenna transmission mode configurating downlink public guide frequency patterns of sub-district; Wherein, the pilot number that disposes respectively on the unit resource piece of the 5th to the 8th antenna port is less than or equal to the pilot number that disposes on the unit resource piece of the 3rd or the 4th antenna port;

With said down public guide frequency pattern, be arranged in the subscriber equipment (UE) of affiliated base station, said sub-district and said sub-district.

Preferably; When said network side is 8 antenna transmission mode configurating downlink public guide frequency patterns of sub-district; According to the configuration method for downlink public pilot frequency of first to fourth antenna port among the long evolving system LTE, the down public guide frequency on first to fourth antenna port of 8 antenna transmission mode is configured.

Preferably, the pre-configured said sub-district of network side is supported N antenna transmission mode and 8 antenna transmission mode simultaneously, and is each antenna transmission mode configured bandwidth resource, further comprises after this method:

X1, network side will be notified the UE of said sub-district for the bandwidth resources of each antenna transmission mode configuration through broadcast;

X2, network side adopt the antenna transmission mode that has disposed to send data to said UE;

X3, said UE confirm the antenna transmission mode that adopts according to the frequency domain position at the data place that receives with in advance for the bandwidth resources of each antenna transmission mode configuration;

X4, said UE according to the corresponding down public guide frequency pattern of definite antenna transmission mode, confirm the pilot tone that network side uses when said UE sends data;

Said N is a natural number.

Preferably, said N is 1,2 or 4.

Preferably, this method further comprises:

Reshuffle the bandwidth resources of each antenna transmission mode according to the preset resource distribution cycle.

Preferably, the step of reshuffling the bandwidth resources of each antenna transmission mode comprises the preset resource distribution cycle of said basis:

Network side receives the channel state parameter of each UE feedback in the said sub-district in each preset bandwidth resource distribution cycle;

According to the channel state parameter of said each UE, confirm to send the antenna transmission mode of The data to each UE;

According to said antenna transmission mode, confirm the bandwidth resources of using to each UE transmission data;

According to the said bandwidth resources of using to each UE transmission data, confirm the bandwidth resources demand of each antenna transmission mode;

According to the bandwidth resources demand of said each antenna transmission mode, be each antenna transmission mode configured bandwidth resource, and said bandwidth resources for each antenna transmission mode configuration notified to UE through broadcast.

Preferably, said bandwidth resources demand according to said each antenna transmission mode, for the step of each antenna transmission mode configured bandwidth resource is:

Be 8 antenna transmission mode configured bandwidth resources;

Give the N antenna transmission mode with the bandwidth resource allocation of not configuration.

Preferably,, said channel state parameter is channel quality information, signal to noise ratio and UE translational speed.

Can find out that from above technical scheme the present invention can realize the down public guide frequency configuration of 8 antenna transmission mode, and the down public guide frequency expense is little, can improve system effectiveness.

Description of drawings

Fig. 1 is the down public guide frequency configuration schematic diagram ofprior LTE system 1 antenna port;

Fig. 2 is the down public guide frequency configuration schematic diagram of prior LTE system 2 antenna ports;

Fig. 3 is the down public guide frequency configuration schematic diagram of prior LTE system 4 antenna ports;

Fig. 4 is first kind of down public guide frequency configuration schematic diagram of the embodiment of the invention one 8 antenna ports;

Fig. 5 is second kind of down public guide frequency configuration schematic diagram of the embodiment of the invention one 8 antenna ports;

Fig. 6 is the realization flow figure of the collocation method of the down public guide frequency that proposes of the embodiment of the invention one;

Fig. 7 is the flow chart of a multiple antenna transmission mode of cell configuration and bandwidth resources thereof for the embodiment of the invention;

The preset resource distribution cycle of basis that Fig. 8 proposes for the embodiment of the invention one is reshuffled the flow chart of the bandwidth resources of each antenna transmission mode.

Embodiment

For making the object of the invention, technical scheme and advantage clearer, the present invention is done further to set forth in detail below in conjunction with accompanying drawing.For simplicity, hereinafter is described as the N antenna transmission mode with N * N antenna transmission mode unification.

If the down public guide frequency allocation plan of 8 antenna transmission mode is the down public guide frequency allocation plan of above-mentioned 4 antenna transmission mode of reference fully; The reference symbol expense will be 28.6% so; Can cause in the system expense of down public guide frequency excessive like this; So that influence the throughput of system, when particularly only having small number of users can support 8 antenna transmission mode, serious waste of resources.

In order to solve the excessive problem of down public guide frequency expense; And because 8 antenna transmission mode are useful in the good scene of channel condition more; Relatively low to the degree of dependence of down public guide frequency when UE receives data, the embodiment of the invention one provides following reference symbol collocation method:

The configuration of the down public guide frequency of antenna port 0-3 is identical to the configuration method for downlink public pilot frequency of antenna port 0-3 with existing LTE system.Like this, can be better each antenna transmission mode of compatible existing LTE system, promptly same sub-district can be supported 1/2/4 antenna transmission mode of 8 antenna transmission mode and existing LTE system simultaneously.

The pilot tone of antenna port 4-7 only is used for the channel estimating of respective antenna port; So can adopt lower density; The density of the down public guide frequency of antenna port 4-7 can have two kinds of schemes: first kind; The density of its down public guide frequency equates that with the down public guide frequency density of antenna port 2-3 the configuration pattern of concrete down public guide frequency is as shown in Figure 4 under this situation.Second kind, adopt the density configuration lower with the down public guide frequency density of antenna port 2-3, the configuration pattern of concrete down public guide frequency is as shown in Figure 5 under this situation.

Fig. 6 is the schematic flow sheet of the embodiment of the invention one.As shown in Figure 6, embodiment one mainly comprises:step 601, network side are 8 antenna transmission mode configurating downlink public guide frequency patterns of sub-district; Wherein, the pilot number that disposes respectively on the unit resource piece of the 5th to the 8th antenna port is less than or equal to the pilot number that disposes on the unit resource piece of the 3rd or the 4th antenna port.

Among this paper, first to the 8th line cap is respectively theantenna port 0,1,2,3,4,5,6 and 7 in the preamble;

In this step, the concrete grammar of the down public guide frequency configuration of 4 antenna transmission mode for conventionally known to one of skill in the art, repeats no more at this in the existing LTE system.

In this step, be less than or equal to the pilot number that disposes on the unit resource piece of the 3rd or the 4th antenna port, to reduce the overhead of down public guide frequency through the pilot number that disposes respectively on the unit resource piece that limits the 5th to the 8th antenna port.Here only be defined to be the down public guide frequency quantity of the 5th to the 8th antenna port configuration; The down public guide frequency of this quantity respectively on the unit resource piece of the 5th to the 8th antenna port concrete distribution can adopt several different methods, only need to realize that the even distribution of down public guide frequency on the unit resource piece gets final product.

Step 602, with said down public guide frequency pattern, be arranged among the UE of base station and said sub-district under the said sub-district.

In practical application, base station and subscriber equipment are before coming into operation, and the down public guide frequency pattern of each antenna transmission mode that system supported can default in wherein.Like this, after UE entering system, can confirm the pilot tone that network side uses when said UE sends data according to the down public guide frequency pattern of self preserving.

Embodiment of the invention scheme is also supported one or more antenna transmission mode coexistences in the sub-district, like 8 antennas, and 2 antennas+8 antennas; 4 antennas+8 antennas etc.; This combination can be in localband width configuration 8 antenna transmission mode of sub-district flexibly, and other bandwidth resources are disposed to other antenna transmission mode, efficiently solve the excessive problem of 8 antenna transmission mode expenses; Both satisfied the sub-district average demand, again the part had been optimized.

When only adopting 8 antenna transmission mode, this transmission bandwidth can be the full bandwidth of system, and when multiple antenna transmission mode existed simultaneously, then each transmission mode can only the configuration section bandwidth.

Under the situation of multiple antenna transmission mode coexistence; After UE entering system; The system that need determine earlier is current to be the antenna transmission mode of its configuration; Could confirm the pilot tone that network side uses when said UE sends data according to the down public guide frequency pattern of self preserving corresponding then with said antenna transmission mode.Therefore, when the sub-district will be supported 8 antenna transmission mode simultaneously with other antenna transmission mode, can confirm the pilot tone that network side uses when it sends data, also further comprise the steps after the said step 602 (as shown in Figure 7) for making the UE side:

Step 701, the pre-configured said sub-district of network side are supported N antenna transmission mode and 8 antenna transmission mode simultaneously, and are each antenna transmission mode configured bandwidth resource; Said N is a natural number.

Step 702, network side will be notified the UE of said sub-district for the bandwidth resources of each antenna transmission mode configuration through broadcast;

Step 703, network side adopt the antenna transmission mode that has disposed to send data to said UE;

Step 704, said UE confirm the antenna transmission mode that adopts according to the frequency domain position at the data place that receives with in advance for the bandwidth resources of each antenna transmission mode configuration;

Step 705, said UE according to the corresponding down public guide frequency pattern of definite antenna transmission mode, confirm the pilot tone that network side uses when said UE sends data;

According to flow process shown in Figure 7, multiple antenna mode and bandwidth resources thereof that the sub-district is supported pre-set, and in use, UE receives and demodulating data according to antenna mode that configures and bandwidth resources thereof all the time.As preferable scheme, can reconfigure antenna mode and bandwidth resources that the sub-district is supported according to certain resource distribution cycle, realize the dynamic change of the antenna mode of sub-district.

Fig. 8 shows the process of reshuffling the bandwidth resources of each antenna transmission mode according to the preset resource distribution cycle, comprises the steps:

Step 801: network side receives the channel state parameter of each UE feedback in the said sub-district: channel quality information, signal to noise ratio and UE translational speed in each preset bandwidth resource distribution cycle.

Here, the size of said bandwidth resources configuration cycles can be according to the stability setting of actual channel state, when channel status is more stable, can it be provided with longly, as one month, when channel status is unstable, can be provided with and lacks, as one day.

Step 802:, confirm to send the antenna transmission mode of The data to each UE according to the channel state parameter of said each UE;

The concrete grammar of this step is: according to the preset corresponding channel state parameter span of each antenna transmission mode difference, confirm the channel state parameter corresponding antenna transmission mode of said each UE.

Step 803:, confirm the bandwidth resources of using to each UE transmission data according to said antenna transmission mode;

Step 804:, confirm the bandwidth resources demand of each antenna transmission mode according to the said bandwidth resources of using to each UE transmission data;

Here, can be through the UE quantity of confirming that each antenna transmission mode is disposed, according to the UE quantity that said each antenna transmission mode disposed, and the bandwidth resources used of each UE transmission data, determine the bandwidth resources demand of antenna transmission mode.

Step 805: according to the bandwidth resources demand of said each antenna transmission mode, be each antenna transmission mode configured bandwidth resource, and said bandwidth resources for each antenna transmission mode configuration notified to UE through broadcast.

Preferably, said bandwidth resources demand according to said each antenna transmission mode, for the step of each antenna transmission mode configured bandwidth resource is:

At first be 8 antenna transmission mode configured bandwidth resources; The bandwidth resource allocation that will not dispose is then given other remaining antenna transmission mode.

Here, in order to ensure the stability of bandwidth resources configuration, before said, can also carry out following steps earlier:

Whether the bandwidth resources demand of judging said each antenna transmission mode reaches preset threshold value, if then carry out the said step of each antenna transmission mode configured bandwidth resource that is; Otherwise, no longer be each antenna transmission mode configured bandwidth resource, that is, withdraw from the process that the preset resource distribution cycle of said basis reshuffles the bandwidth resources of each antenna transmission mode.

The above is merely preferred embodiment of the present invention, not in order to restriction the present invention, all any modifications of within spirit of the present invention and principle, being done, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.

Claims (6)

1. the collocation method of a down public guide frequency is characterized in that, this method comprises:

The pre-configured sub-district of network side is supported N antenna transmission mode and 8 antenna transmission mode simultaneously, and is each antenna transmission mode configured bandwidth resource,

Network side is 8 antenna transmission mode configurating downlink public guide frequency patterns of said sub-district; Wherein, the pilot number that disposes respectively on the unit resource piece of the 5th to the 8th antenna port is less than or equal to the pilot number that disposes on the unit resource piece of the 3rd or the 4th antenna port;

With said down public guide frequency pattern, be arranged in the user equipment (UE) of affiliated base station, said sub-district and said sub-district;

Network side will be notified the UE of said sub-district for the bandwidth resources of each antenna transmission mode configuration through broadcast;

Network side adopts the antenna transmission mode that has disposed to send data to said UE;

Said UE confirms the antenna transmission mode that adopts according to the frequency domain position at the data place that receives with in advance for the bandwidth resources of each antenna transmission mode configuration;

Said UE according to the corresponding down public guide frequency pattern of definite antenna transmission mode, confirm the pilot tone that network side uses when said UE sends data;

Said N is 1,2 or 4.

2. method according to claim 1; It is characterized in that; When said network side is 8 antenna transmission mode configurating downlink public guide frequency patterns of sub-district; According to the configuration method for downlink public pilot frequency of first to fourth antenna port in the Long Term Evolution LTE system, the down public guide frequency on first to fourth antenna port of 8 antenna transmission mode is configured.

3. method according to claim 1 is characterized in that, this method further comprises:

Reshuffle the bandwidth resources of each antenna transmission mode according to the preset resource distribution cycle.

4. method according to claim 3 is characterized in that, the step that the preset resource distribution cycle of said basis is reshuffled the bandwidth resources of each antenna transmission mode comprises:

Network side receives the channel state parameter of each UE feedback in the said sub-district in each preset bandwidth resource distribution cycle;

According to the channel state parameter of said each UE, confirm to send the antenna transmission mode of The data to each UE;

According to said antenna transmission mode, confirm the bandwidth resources of using to each UE transmission data;

According to the said bandwidth resources of using to each UE transmission data, confirm the bandwidth resources demand of each antenna transmission mode;

According to the bandwidth resources demand of said each antenna transmission mode, be each antenna transmission mode configured bandwidth resource, and said bandwidth resources for each antenna transmission mode configuration notified to UE through broadcast.

5. method according to claim 4 is characterized in that, said bandwidth resources demand according to said each antenna transmission mode, for the step of each antenna transmission mode configured bandwidth resource is:

Be 8 antenna transmission mode configured bandwidth resources;

Give the N antenna transmission mode with the bandwidth resource allocation of not configuration.

6. method according to claim 4 is characterized in that, said channel state parameter is channel quality information, signal to noise ratio and UE translational speed.

Images