CN101615936B - Method for forming downlink beam - Google Patents

Abstract

The invention discloses a method for forming a downlink beam. The method comprises the following steps: combining EBB according to the channel impulse response of all uplink channels and the signal-noise-ratio SNR of all channels, which are obtained by performing channel evaluation on all uplink channels of all uplink time slots in a current sub-frame by UE and obtaining EBB weight vector combined according to SNR; and carrying out downlink beam forming on a transmission signal of all downlink channels of the UE in the Dulth sub-frame behind the current sub-frame by using the EBB weight vector which is combined according to the SNR, wherein the Dul is time delay for generating the EBB weight vector. Therefore, the method can avoid the problem that a single channel may cause reduced generation frequency of the EBB weight vector due to interval transmission, thereby improving the DLBF performance of the downlink channel.

Description

A kind of downlink wave beam formation method

Technical field

The present invention relates to the wave beam forming technology, particularly a kind of downlink wave beam formation method.

Background technology

In GSM, a UE possibly be assigned with a plurality of up channels, for example; A UE has UL DPCH; HSDPA UE possibly be assigned with HS-SICH in some subframe, and HSUPA UE possibly have the E-PUCH of non-scheduling, also possibly be assigned with the E-PUCH of scheduling in some subframe.Therefore, a UE at most maybe be at the up UL DPCH that has simultaneously, the E-PUCH of non-scheduling, the E-PUCH of HS-SICH and scheduling.Certainly, according to existing 3GPP standard, in same subframe, the E-PUCH of scheduling and the E-PUCH of non-scheduling can not occur simultaneously; At same time slot, E-PUCH (scheduling or non-scheduling) and HS-SICH, UL DPCH can not occur simultaneously.

Above-mentioned up channel UL DPCH, E-PUCH, HS-SICH and the scheduling E-PUCH of non-scheduling have following characteristics:

DTX (Discontinuous Transmission) possibly appear in UL DPCH; And the UL DPCH of certain UE possibly share same physical resource through Time Division Multiplexing mode and other UE; And under this TDM mode, exist usually at interval between two adjacent UL DPCH cycles of a UE; The E-PUCH of non-scheduling gives UE through the TDM parameter configuration, and therefore the E-PUCH cycle of adjacent two non-scheduling also exists at interval usually; And for the E-PUCH of HS-SICH and scheduling, these two channels are shared channels, and therefore, UE is difficult to forever take this two channels.

In sum, E-PUCH, HS-SICH and the scheduling E-PUCH of the UL DPCH of a UE, non-scheduling all are likely discontinuous.

At present, for improving the quality of reception of UE down channel, adopt downlink wave beam to form (DLBF) technology usually.More common a kind of DLBF technology is EBB algorithm (being the characteristic vector method); When a down channel wave beam that utilizes this method to UE forms; Usually according to reception signal this UE and up channel this down channel pairing; Generate downlink wave beam through the EBB algorithm and form weight vector, the downlink wave beam that is used for this down channel forms.

Specifically, for the up channel that only occupies a time slot, downlink wave beam formation method comprises:

Step 1: judge whether current subframe " n " belongs to this up channel.

Such as: for the UL DPCH through the TDM parameter configuration, in the cycle, having only the part subframe is the subframe that belongs to this UL DPCH at each TDM, and other subframes then do not belong to this up channel.

Step 2: for the subframe n that belongs to this channel, carry out channel estimating, obtain the channel impulse response of this channel on every antenna of this UE.Specific as follows:

By the reception signal in Midamble territory on the every antenna, obtain the channel impulse response of all Midamble Shift on each root antenna through channel estimating.NODEB knows the Midmable Shift that the up channel of this UE adopts.Therefore, NODEB knows the channel impulse response of this UE on every antenna.

Step 3: by the covariance matrix R of the channel impulse response signal calculated of this channel _s(n):

$R_s\left(n\right)=\left[\begin{array}{c}{h}_1\\ h_2\\ .\\ .\\ .\\ h_k\\ .\\ .\\ .\\ h_K\end{array}\right]\left[\begin{array}{cccccc}{h}_1& h_2& ...& h_k& ...& h_K\end{array}\right]$

Here, h _kBeing the channel impulse response of this channel of this UE on k root antenna, is the row vector of a W dimension, and W is that the window of channel impulse response is long, h _kIn n path of n element representation at the fading factor of k root antenna, also be the channel impulse response value of n path at k root antenna.

Step 4: it is average that the covariance matrix Rs (n) of signal is carried out recurrence.

${\stackrel{\‾}{R}}_s\left(n\right)={(1-p)}^m{\stackrel{\‾}{R}}_s(n-m)+(1-{(1-p)}^m)p{R}_s\left(n\right)$

Here, and p ∈ (0,1] be forgetting factor, can get $p=\frac{1}{16},$ Subframe (n-m) is a subframe nearest apart from subframe n that belongs to this this channel of UE.This up channel that does not belong to this UE in subframe (n-m) to the every other subframe between the subframe n.

Step 5: the covariance matrix by signal calculates the EBB weight vector.

EBB weight vector w satisfies: $R_n^{-1}{\stackrel{\‾}{R}}_{s}w={\mathrm{\λ}}_{\mathrm{Max}}w.$ That is: w is R _n ^-1R _sEigenvalue of maximum characteristic of correspondence vector.Here, w is the column vector of a K dimension, and K is the antenna sum, R _nIt is the covariance matrix of noise.Noise power through trying to achieve every antenna just can obtain this matrix.Concrete R _nThe method of asking can repeat no more here referring to existing method.

Can try to achieve satisfied according to existing method $R_n^{-1}{\stackrel{\‾}{R}}_{s}w={\mathrm{\λ}}_{\mathrm{Max}}w$ W.Here repeat no more.

Step 6: the EBB weight vector by the n subframe of trying to achieve can carry out DLBF at the signal of (n+Dul) subframe transmission to the down channel of this up channel pairing.

If the corresponding downstream channel (n+Dul) subframe on k root antenna, send signal be s (k l), then passes through DLBF, and the signal that this channel sends on k root antenna in (n+Dul) subframe is:

(k, l), w (k) is k the element of w to w (k) s here.That is: w=[w (1), w (2) ..., w (K)] ^TIf at n subframe this up channel of this UE not, then when (n+Dul) subframe is sent the corresponding down channel of this UE, adopt (n+Dul-1) subframe to send the EBB weight vector that adopts when this down channel carries out DLBF.If this down channel of (n+Dul-1) subframe does not have signal to send, then adopt a nearest subframe that has this downlink channel signals to send of distance (n+Dul) subframe, adopt the EBB weight vector of this subframe to carry out the DLBF of current subframe.

So far, existing downlink wave beam forms the method flow end.In said process, the EBB of the up channel of a UE and the DLBF of down channel independently carry out respectively.That is: in existing EBB and DLBF method, in the NODEB side, each up channel of each UE carries out EBB respectively, and for a up channel that occupies a plurality of time slots, each time slot of this channel is to carry out EBB's separately.In the NODEB side, each down channel of this UE carries out DLBF respectively, adopts the EBB weight vector of the up channel generation of pairing separately to carry out DLBF respectively.If the up channel of pairing does not have newly-generated EBB weight vector; Just adopt this down channel to carry out DLBF at the EBB weight vector that previous subframe adopts; If this down channel of last subframe does not have signal to send, the EBB weight vector that adopts with regard to the descending sub frame that adopts nearest this down channel of the current descending sub frame of distance carries out DLBF.Such as, the current nearest subframe that belongs to this down channel of subframe down of distance is subframe " n-m ", n is current subframe number, carries out DLBF with regard to the EBB weight vector that adopts " n-m " subframe.As previously mentioned, all up channels of UE all possibly occur sending and are interrupted, and therefore, the frequency that the method that existing each up channel independently carries out EBB generates the EBB weight vector is lower, the DLBF decreased performance of the down channel that correspondingly matches with this up channel.

Below, illustrate the weak point that existing EBB and DLBF method demonstrate in each up-downgoing channel that disposes in pairs.

For example, UL DPCH and the DL DPCH of a UE dispose in pairs, and according to the signal generation EBB weight vector of UL DPCH, the downlink wave beam that is used for the DL DPCH of this UE forms.Specifically, establishing NODEB is Dul according to the time delay that the reception signal of a channel generates the EBB weight vector.Then NODEB is according at the reception signal of the UL of n sub-frame DPCH, and the EBB weight vector of the n frame of generation can be used for the DLBF of (n+Dul) subframe DL DPCH.When UL DPCH was in UL DTX, UE sent special burst (SB, Special Burst) periodically, and between two SB, UE does not send data.In the subframe that UE does not send UL DPCH signal, NODEB just can't generate the EBB weight vector according to this subframe signal.This frequency that must make UL DPCH channel generate the EBB weight vector descends, thereby makes the DLBF decreased performance of DL DPCH.At present; NODEB is during UL DPCH is in UL DTX; When sending DL DPCH; Adopt the UL DPCH of this UE to get into the EBB weight vector that UL DTX last subframe before generates; If that is: the m subframe is that the UL DPCH of UE gets into last subframe before the UL DTX, the EBB weight vector that NODEB adopts the m subframe to generate is used for n, and (DLBF of the DL DPCH of subframe of n＞=m+Dul) is till NODEB can generate new EBB weight vector by the reception data of this up channel.

Again for example, HS-SICH and HS-SCCH are configurations in pairs.Corresponding with each dispatching cycle of UE, there are identical HS-SCCH dispatching cycle of length and HS-SICH dispatching cycle.Have timing difference T1 between HS-SCCH and the HS-SICH, because the existence of T1, also early finish T1 sub-frame than the early T1 sub-frame that the begins dispatching cycle of corresponding HS-SICH the dispatching cycle of HS-SCCH.Signal according to HS-SICH generates the EBB weight vector, and the downlink wave beam that is used for the HS-SCCH of this UE forms.But; Because HS-SCCH is than the early T1 sub-frame that begins of HS-SICH; And the time delay of NODEB generation EBB weight vector is Dul; Therefore, initial (T1+Dul-1) sub-frame of each HS-SCCH dispatching cycle also can't obtain receiving the EBB weight vector that signal generates by HS-SICH carrying out downlink wave beam when forming.If this UE has disposed UL DPCH, can consider to adopt the weight vector that generates by UL DPCH in initial (T1+Dul-1) sub-frame.But as stated, possibly there is DTX in UL DPCH, at initial (T1+D _Ul-1) sub-frame, the UL DPCH of this UE possibly be in UL DTX.Therefore, the downlink wave beam of initial (T1+Dul-1) individual HS-SCCH subframe formation performance can't guarantee.

Again for example, the E-PUCH of the E-AGCH of scheduling and scheduling occurs in pairs.Relation object between E-AGCH and the E-PUCH is similar to the relation between HS-SCCH and the HS-SICH.There is fixing timing difference T2=2 between E-AGCH and the E-PUCH.That is: also early finish 2 sub-frame always than early 2 sub-frame that the begin dispatching cycle of corresponding E-PUCH the dispatching cycle of each E-AGCH.The wave beam of E-AGCH forms the reception signal of E-PUCH that can adopt from scheduling and carries out through the weight vector that the EBB algorithm obtains.The EBB weight vector similar with HS-SCCH, that the individual E-AGCH subframe of initial (T2+Dul-1) can't utilize the E-PUCH subframe to generate.If utilize the EBB weight vector of UL DPCH, its performance also can't guarantee because UL DPCH has UL DTX.

Certainly, HSUPD UE possibly be configured the E-PUCH of non-scheduling.At present, there is not DLBF in the down channel E-HICH with the E-PUCH of non-scheduling pairing.Therefore, the EBB weight vector of E-PUCH can generate, and also can not generate.

Be the defective of existing EBB of example explanation and DLBF below with the concrete TDM cycle.As shown in Figure 1, UE1 has been assigned with the E-PUCH of UL DPCH and non-scheduling simultaneously on up direction.

The TDM parameter of UL DPCH is: the TDM cycle is 4 TTI, and TTI=10ms=2 5ms subframe is the TDM of 4 TTI in the cycle in each length, and preceding 2 TTI are assigned to this UE1.With the TDM cycle of the DL DPCH of UL DPCH pairing be 4 TTI, TTI=10ms is the TDM of 4 TTI in the cycle in each length, preceding 2 TTI are assigned to this UE1.The TDM cycle starting point of UL DPCH is than Zao two TTI of the starting point in the TDM cycle of DL DPCH.

Fig. 1 has provided two TDM cycles of UL DPCH and two TDM cycles of DL DPCH.First subframe number of Fig. 1 is n, and the solid arrow in the sensing representes to distribute to the UL DPCH of UE1, and the solid arrow under pointing to representes to distribute to the DL DPCH of UE1.Beginning to subframe n+7 from subframe n is the TDM cycle of first UL DPCH, and wherein, subframe n, n+1, n+2, n+3 are this TDM distributes to UE1 in the cycle UL DPCH subframes.From subframe n+8 to subframe n+15 is the TDM cycle of second UL DPCH, and wherein, subframe n+8, n+9, n+10, n+11 are this TDM distributes to UE1 in the cycle UL DPCH subframes.Beginning to subframe n+11 from subframe n+4 among Fig. 1 is the TDM cycle of first DL DPCH, and wherein, subframe n+4, n+5, n+6, n+7 are this TDM distributes to UE1 in the cycle DL DPCH subframes.From subframe n+12 to subframe n+19 is the TDM cycle of second DL DPCH, and wherein, subframe n+12, n+13, n+14, n+15 are this TDM distributes to UE1 in the cycle DL DPCH subframes.

The TDM parameter of E-PUCH of distributing to the non-scheduling of this UE1 is: the TDM cycle is 4 TTI, and TTI=10ms is the TDM of 4 TTI in the cycle in each length, and back 2 TTI are assigned to this UE.And timing difference is the T=2 sub-frame between the E-HICH of the non-scheduling of the E-PUCH of non-scheduling pairing and the E-PUCH.

Fig. 1 gives two TDM cycles of E-HICH of two TDM cycles and non-scheduling of the E-PUCH of non-scheduling.As shown in Figure 1, the dotted arrow in the sensing representes to distribute to the E-PUCH of the non-scheduling of UE1, and the dotted arrow under pointing to representes to distribute to the E-HICH of the non-scheduling of UE1.Beginning to subframe n+7 from subframe n is the TDM cycle of first non-scheduling E-PUCH, and wherein, subframe n+4, n+5, n+6, n+7 are this TDM distributes to UE1 in the cycle E-PUCH subframes; Beginning to subframe n+15 from subframe n+8 is the TDM cycle of second non-scheduling E-PUCH, and wherein, subframe n+12, n+13, n+14, n+15 are this TDM distributes to UE1 in the cycle E-PUCH subframes.

When the E-PUCH of UL DPCH and non-scheduling generates the EBB weight vector respectively, in first ULDPCH cycle, have only four UL DPCH subframes, each subframe NODEB can generate an EBB weight vector.If it is the Dul=1 sub-frame that NODEB generates the time delay of EBB weight vector.NODEB is at subframe n, and n+1, n+2, n+3 generate four EBB weight vectors respectively, should be respectively applied for subframe n+1, n+2, the DLBF of the DLDPCH of n+3 and n+4.But because DLDPCH only has signal to send at subframe n+4, therefore, at subframe n, n+1, the EBB weight vector that n+2 generates is not used, and has directly abandoned.DL DPCH is at subframe n+5, and n+6 is when n+7 sends signal; Because UL DPCH is at n+4, n+5, n+6 do not have signal to send; NODEB does not have newly-generated EBB weight vector, therefore, can only be employed in the EBB weight vector that the n+3 subframe generates at this three sub-frame DL DPCH; That is: owing to there is not newly-generated EBB weight vector, the EBB weight vector that adopts in the time of can only adopting previous DL DPCH subframe to send carries out DLBF.

Second UL DPCH cycle, processing mode is with first UL DPCH TDM cycle.Repeat no more.Therefore; Can see:, when DL DPCH only adopts the EBB weight vector of ULDPCH generation, be the TDM cycle of 8 sub-frame in each length when UL DPCH independently generates the EBB weight vector; Can only generate four EBB weight vectors, and adopt have only an EBB weight vector.Is the TDM of 8 sub-frame in the cycle for DL DPCH in each length, and four continuous sub-frame adopt an identical EBB weight vector to carry out DLBF.The performance of DLBF descends because the generated frequency of EBB weight vector is very low.

E-PUCH for non-scheduling.In first E-PUCH cycle, have only four E-PUCH subframes, each subframe NODEB can generate an EBB weight vector.But according to existing method, the weight vector that it generates is not applied to DL DPCH.

Summary of the invention

In view of this, the present invention provides a kind of downlink wave beam formation method, can improve the DLBF performance of down channel.

For realizing above-mentioned purpose, the present invention adopts following technical scheme:

A kind of downlink wave beam formation method comprises:

Based on the channel impulse response that UE all up channels of all ascending time slots in current subframe is carried out said all up channels that channel estimating obtains and the signal to noise ratio snr of said all channels; Associating EBB obtains according to the EBB weight vector after the SNR merging;

Utilize said EBB weight vector after merging according to SNR, the transmission signal of the Dul sub-frame of all down channels after current subframe of said UE is carried out downlink wave beam form, said Dul is for generating the time delay of EBB weight vector.

Preferably, said basis is carried out the channel impulse response of said all up channels that channel estimating obtains and the signal to noise ratio snr of said all channels to UE all up channels of all ascending time slots in current subframe, unites EBB and comprises:

According to the SNR of said all up channels, merge the up channel impulse response of said all channels;

The covariance matrix of the said up channel impulse response signal calculated after utilize merging, and it is average that said covariance matrix is carried out recurrence, calculates the EBB weight vector according to the recurrence average result, with it as said EBB weight vector after merging according to SNR.

Preferably, said SNR according to all up channels, the up channel impulse response that merges said all channels is:

According to $h_k=\frac{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\·h_k^{k_m\left(c\left(t_n\right)\right)}\left(t_n\right)}{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the channel impulse response after merging on the k root reception antenna, wherein, 0＜k≤K, K are the reception antenna sum, t _n, n=1,2 ..., T is distributed with the time slot that belongs to said UE up channel, c (t _n) be at time slot t _nThe up channel numbering that belongs to said UE, C (t _n) be at time slot t _nThe up channel sum that belongs to said UE,

For said UE at time slot t _nC (t _n) channel impulse response of individual up channel, SNR (c (t _n)) be that said UE is at time slot t _nC (t _n) signal to noise ratio of individual up channel, k _m(c (t _n)) be that said UE is at time slot t _nC (t _n) the Midamble Shift that adopts of individual up channel;

Channel impulse response after merging on the every reception antenna is combined into column vector, constitutes the up channel impulse response H of said all channels.

Preferably, said SNR according to all up channels, the up channel impulse response that merges said all channels is: select the up channel impulse response H of the channel impulse response of the maximum up channel of SNR as said all channels after merging.

Preferably, said basis is carried out the channel impulse response of said all up channels that channel estimating obtains and the signal to noise ratio snr of said all channels to UE all up channels of all ascending time slots in current subframe, unites EBB and comprises:

Based on the channel impulse response that UE each up channel of each ascending time slot in current subframe is carried out each up channel that channel estimating obtains; Calculate the corresponding covariance matrix of said each up channel; And it is average that each covariance matrix is carried out recurrence respectively, calculates the corresponding EBB weight vector of said each up channel based on the recurrence average result again;

According to the SNR of said each up channel, merge the corresponding EBB weight vector of said each up channel, with amalgamation result as said EBB weight vector after merging according to SNR.

Preferably, the said corresponding EBB weight vector of said each up channel of SNR merging according to each up channel is:

According to $w=\frac{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\·w(c\left(t_n\right),t_n)}{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the corresponding EBB weight vector of each up channel, wherein, t _n, n=1,2 ..., T is distributed with the time slot that belongs to said UE up channel, c (t _n) be at time slot t _nThe up channel numbering that belongs to said UE, C (t _n) be at time slot t _nThe up channel sum that belongs to said UE, w (c (t _n), t _n) be at time slot t _nUp channel c (t _n) the EBB weight vector that generates, SNR (c (t _n)) be that said UE is at time slot t _nC (t _n) signal to noise ratio of individual up channel.

Preferably, said SNR according to each up channel merges the corresponding EBB weight vector of said each up channel and is: select the corresponding EBB weight vector of the maximum up channel of SNR as said EBB weight vector after merging according to SNR.

Preferably; This method further comprises: if do not have the up channel that belongs to said UE in the current subframe; Then when the transmission signal to the Dul sub-frame after the current subframe carries out downlink wave beam formation; Utilize nearest one of the current subframe of distance have the up channel that belongs to said UE subframe, generated merge according to SNR after the EBB weight vector, carry out said downlink wave beam and form.

Visible by technique scheme, among the present invention, at first UE all up channels of all ascending time slots in current subframe are carried out channel estimating, obtain the channel impulse response of all up channels; Then, unite EBB, obtain according to the EBB weight vector after the SNR merging according to the channel impulse response and the signal to noise ratio (snr) of all channels; At last, utilize said EBB weight vector after merging according to SNR, the transmission signal of the Dul sub-frame of all down channels after current subframe of said UE is carried out downlink wave beam form, Dul is for generating the time delay of EBB weight vector.Method through the invention described above; Make when carrying out the generation of EBB weight vector; Uniting in the current subframe all up channels that belong to UE carries out; Thereby the problem of the EBB weight vector generated frequency reduction that causes is sent at the interval of avoiding individual channel to occur, and then improves the DLBF performance of down channel.

Description of drawings

Fig. 1 is with the multiplexing sketch map of TDM mode.

Fig. 2 is the overview flow chart of downlink wave beam formation method among the present invention.

Fig. 3 is the particular flow sheet of downlink wave beam formation method in the embodiment of the invention one.

Fig. 4 is the particular flow sheet of downlink wave beam formation method in the embodiment of the invention two.

Embodiment

For making the object of the invention, technological means and advantage clearer, below in conjunction with accompanying drawing the present invention is done to describe in further detail.

Basic thought of the present invention is: the channel impulse response of all up channels that belong to certain UE of all time slots in the subframe is joined together, generate the EBB weight vector, be used to carry out downlink wave beam and form.

Fig. 2 is for being used to carry out the overview flow chart of downlink wave beam formation method among the present invention.As shown in Figure 2, this method comprises:

Step 201 is carried out channel estimating to UE all up channels of all ascending time slots in current subframe, obtains the channel impulse response of these all up channels.

Step 202, channel impulse response and SNR according to all up channels that belong to this UE in the current subframe unite EBB, obtain according to the EBB weight vector after the SNR merging.

Step 203 is utilized the EBB weight vector after merging according to SNR of obtaining in the step 202, the transmission signal of the Dul sub-frame of all down channels after current subframe of UE is carried out downlink wave beam form.

Wherein, Dul is for generating the time delay of EBB weight vector.

So far, the method flow of downlink wave beam formation of the present invention finishes.

In the said method flow process; Unite the mode that EBB obtains the EBB weight vector in the step 202 and can have two kinds; First kind is that channel impulse response to all up channels merges by SNR, utilizes channel impulse response after merging to carry out EBB again and obtains the EBB weight vector; Second kind is that channel impulse response according to each up channel carries out EBB, obtains the corresponding EBB weight vector of each up channel, the more corresponding EBB weight vector of each up channel is merged the EBB weight vector after obtaining merging according to SNR.Be described in detail below by the concrete realization of specific embodiment above-mentioned dual mode.

Embodiment one:

Adopt first kind of mode when uniting EBB in the present embodiment, promptly the channel impulse response to all channels merges, and carries out the mode of EBB then.

Fig. 3 is the particular flow sheet of downlink wave beam formation method in the embodiment of the invention one.Form example and describe UE1 is carried out downlink wave beam among this embodiment, as shown in Figure 3, this method flow comprises:

Step 301, all possible up channel of record UE1.

If UE1 has been configured UL DPCH, then UL DPCH is exactly the up channel of this UE, if this UE1 has been configured non-scheduling E-PUCH, then non-scheduling E-PUCH is exactly the up channel of this UE.If this UE1 is a HSDPA UE, promptly this UE has applied for that HSDPA is professional, and then HS-SICH is exactly the possible up channel of this UE1.When this UE1 by descending being scheduled the time, this UE can be assigned with the HS-SCCH of a scheduling and the HS-SICH of a scheduling.In the dispatching cycle of the HS-SICH of this scheduling, the HS-SICH of this scheduling is exactly a up channel that belongs to this UE1.In like manner, for a HSUPAUE, the E-PUCH of scheduling is the possible up channel of this UE1.As this UE up being scheduled the time, this UE can be assigned with the E-AGCH of a scheduling and the E-PUCH of scheduling.In the dispatching cycle of this UE1, the E-AGCH of scheduling just belongs to the down channel of this UE, and the E-PUCH of scheduling is exactly the up channel that belongs to this UE1.The institute of this UE1 might up channel, comprises all up channels and all possible up channel of this UE1.

Step 302 judges at current subframe n whether the up channel that belongs to UE1 is arranged, if the up channel that belongs to this UE1 is arranged, then execution in step 303, otherwise, return step 302, wait for the arrival of next subframe.When next subframe arrived, execution in step 302 again.

For example: for the UL DPCH through the TDM parameter configuration, as shown in Figure 1, preceding four sub-frame in each TDM cycle have the channel that belongs to this UE, and this channel is UL DPCH.Other four sub-frame in each TDM cycle also have the up channel that belongs to this UE, and this channel is the E-PUCH of non-scheduling.UE can be one by one all possible up channel of this UE of inquiry whether belong to this UE in current subframe.

Step 303 at current subframe n, is carried out channel estimating in each has the ascending time slot of the up channel that belongs to this UE, obtain belonging in each time slot the channel impulse response of each up channel of this UE.

Be located at current subframe n, the up channel that belongs to this UE is distributed in T ascending time slot: t ₁, t ₂..., t _TAt time slot t _n, n=1,2 ..., T, the channel that belongs to this UE has C (t _n) individual.At time slot t _nReception signal through to Midamble territory on the k root antenna carries out channel estimating, can obtain the channel impulse response of all MidambleShift on this antenna k _m=1,2 ..., K _m, here,

Expression Midamble shift " k _m" channel impulse response, K _mIt is the sum of Midamble shift.If the c (t of this UE _n) the Midmable Shift that adopts of individual up channel is k _m(c (t _n)), therefore, this UE is at time slot t _nC (t _n) channel impulse response of individual up channel does

Step 304 merges at the channel impulse response of all up channels of this subframe this UE1 according to SNR, obtains a unique channel impulse response.

If the signal to noise ratio of this up channel is SNR (c (t _n)), SNR (c (t _n)) can adopt existing signal-noise ratio computation method to calculate, repeat no more here.Then according to SNR merge obtain this UE unique channel impulse response of this subframe can for:

According to $h_k=\frac{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\·h_k^{k_m\left(c\left(t_n\right)\right)}\left(t_n\right)}{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the channel impulse response after merging on the k root reception antenna, then the channel impulse response after merging on the every reception antenna is combined into column vector, constitute the up channel impulse response H of said all channels.

Perhaps, in order to simplify calculating, also can directly choose the channel impulse response of the maximum up channel of SNR, the channel impulse response H that this channel impulse response is obtained as all up channels merging of all ascending time slots in this subframe in this step.

If only have a up channel in current subframe, then directly with the channel impulse response of this up channel as the up channel impulse response after merging.

Step 305, the covariance matrix of unique channel impulse response signal calculated of this UE that obtains by merging.

Particularly, signal calculated covariance matrix R _s(n) mode is:

$R_s\left(n\right)=\left[\begin{array}{c}{h}_1\\ h_2\\ .\\ .\\ .\\ h_k\\ .\\ .\\ .\\ h_K\end{array}\right]\left[\begin{array}{cccccc}{h}_1& h_2& ...& h_k& ...& h_K\end{array}\right]$

Step 306, it is average that the covariance matrix Rs (n) of signal is carried out recurrence.

R _s(n)＝(1-p) ^mR _s(n-m)+(1-(1-p) ^m)pR _s(n)

Here, and p ∈ (0,1] be forgetting factor, can get $p=\frac{1}{16}.$ (n-m) has the up channel that belongs to this UE in subframe, all do not belong to the up channel of this UE to the every other subframe between the subframe n in subframe (n-m).

Step 307 is calculated the EBB weight vector by the recurrence average result of the covariance matrix of signal.

EBB weight vector w satisfies: $R_n^{-1}{\stackrel{\‾}{R}}_{s}w={\mathrm{\λ}}_{\mathrm{Max}}w.$ That is: w is R _n ^-1R _sEigenvalue of maximum characteristic of correspondence vector.Here, w is the column vector of a K dimension, and K is the antenna sum, R _nBe the covariance matrix of noise, just can obtain this matrix, R through the noise power of trying to achieve every antenna _s(n) the recurrence average result that obtains for step 306.Concrete R _nThe method of asking can repeat no more here referring to existing method.

Can try to achieve satisfied according to existing method $R_n^{-1}{\stackrel{\‾}{R}}_{s}w={\mathrm{\λ}}_{\mathrm{Max}}w$ W.Here repeat no more.

Step 308 is carried out DLBF according to the EBB weight vector of the n subframe that calculates in the step 307 to the signal that all down channels of this UE1 send in (n+Dul) subframe.

Particularly, a down channel establishing this UE (n+Dul) subframe on k root antenna, send signal be s (k, l); Then pass through DLBF; The signal that this channel sends on k root antenna in (n+Dul) subframe is: (k, l), w (k) is k the element of w to w (k) s here.That is: w=[w (1), w (2) ..., w (K)] ^TBy above-mentioned visible, when generating the EBB weight vector, all time slots of all up channels are joined together to generate the EBB weight vector in the embodiment of the invention.Like this,, and utilize this EBB to carry out the DLBF of any down channel, improved the performance of DLBF as long as in subframe, comprise and promptly can carry out EBB by the up channel that belongs to UE1.

In above-mentioned flow process; The probability that can't generate the EBB weight vector reduces greatly; But do not get rid of the situation that exception is arranged yet, any up channel of this UE1 not among the promptly current subframe n, at this moment; Can, (n+Dul) subframe adopt (n+Dul-1) subframe to send the EBB weight vector that adopts when this down channel carries out DLBF when sending any one down channel of this UE.If at (n-1) subframe any up channel of this UE not; Then when (n+Dul) subframe is sent any one down channel of this UE; Adopt a nearest subframe, the EBB weight vector that adopts this subframe to generate with the up channel that belongs to this UE.Such as, in (n-m) subframe, this UE has the up channel that belongs to it, and between (n-m) subframe and (n+Dul) subframe, does not belong to the up channel of this UE.So, when (n+Dul) subframe is sent any one down channel of this UE, the EBB weight vector that adopts (n-m) subframe to generate.

So far, the method flow that downlink wave beam forms in the present embodiment finishes.

Embodiment two:

Adopt the second way when uniting EBB in the present embodiment, promptly the channel impulse response of all channels is carried out EBB and obtain a plurality of EBB weight vectors, the mode that again the EBB weight vector that obtains is merged.

Fig. 4 is the particular flow sheet of downlink wave beam formation method in the embodiment of the invention two.Form example and describe UE1 is carried out downlink wave beam among this embodiment, as shown in Figure 4, this method flow comprises:

Step 401, all possible up channel of record UE1.

Step 402 judges in current subframe " n " whether the up channel that belongs to UE1 is arranged, if the up channel that belongs to this UE1 is arranged, then execution in step 303, otherwise, return step 302, wait for the arrival of next subframe.When next subframe arrived, execution in step 302 again.

Step 403 at current subframe n, is carried out channel estimating in each has the ascending time slot of the up channel that belongs to this UE, obtain belonging in each time slot the channel impulse response of each up channel of this UE.

Identical in step 301～303 among the operation of above-mentioned steps 401～403 and the embodiment one, just repeat no more here.

Step 404, the channel impulse response of each up channel that obtains according to step 403 carries out EBB, obtains the EBB weight vector of corresponding each up channel.

Specifically carrying out EBB according to channel impulse response, to obtain the mode of EBB weight vector identical with existing implementation, for example adopts the mode in step 3 in the background technology～5, just repeats no more here.

Step 405 merges the corresponding EBB weight vector of all up channels that obtains in the step 404 according to SNR, obtains a unique EBB weight vector.

In this step, the mode that the EBB weight vector is merged according to SNR can for:

According to $w=\frac{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\·w(c\left(t_n\right),t_n)}{\underset{n=1}{\overset{T}{\mathrm{\Σ}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\Σ}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the corresponding EBB weight vector of each up channel.Wherein, t _n, n=1,2 ..., T is the time slot that is distributed with the up channel that belongs to UE1, c (t _n) be at time slot t _nThe up channel numbering that belongs to UE1, C (t _n) be at time slot t _nThe up channel sum that belongs to UE1, w (c (t _n), t _n) be illustrated in time slot t _nChannel c (t _n) the EBB weight vector that generates.

Perhaps, in order to simplify calculating, the EBB weight vector of up channel generation that also can be directly that SNR in all up channels is maximum adopts this weight vector to carry out the DLBF of these all down channels of UE1 as the EBB weight vector after merging.Such as: in all up channels, channel c (t _n) SNR maximum, can be with the EBB weight vector w (c (t of this channel _n), t _n) be used for the DLBF of these all down channels of UE.

Step 406 is carried out DLBF according to the EBB weight vector of the n subframe that calculates in the step 407 to the signal that all down channels of this UE1 send in (n+Dul) subframe.

Identical in operation in this step and embodiment one step 308 just repeated no more here.

So far, the idiographic flow of the downlink wave beam formation method in the present embodiment finishes.

Above-mentionedly be embodiment of the present invention, in sum, in the method for the present invention, the EBB that all up channels of UE are united, and utilize this EBB to carry out the DLBF of all down channels of this UE.Specifically comprise:

1,, belongs to each up channel of this UE for each UE record in the NODEB side.These up channels possibly comprise at present: the E-PUCH of the E-PUCH of UL DPCH, non-scheduling, HS-SICH and scheduling;

2, when an ascending time slot in a sub-frame, if when this UE has a plurality of up channel simultaneously, the channel impulse response that is then obtained by all these up channels merges according to the signal to noise ratio of each up channel and obtains a unique channel impulse response;

3, when in a sub-frame, this UE has a plurality of ascending time slots, and when this UE of each ascending time slot had at least one up channel, this UE can join together to generate unique channel impulse response at all up channels of all ascending time slots.Specifically, this UE merges according to signal to noise ratio at the channel impulse response of all up channels of all ascending time slots, obtains a unique channel impulse response;

4, the unique channel impulse response that is obtained in a sub-frame by this UE obtains the signal covariance matrix of this UE in this subframe, and it is average that signal covariance matrix is carried out recurrence.Then, the signal covariance matrix that is on average obtained by recurrence obtains this UE at the EBB of this subframe weight vector.

Through the downlink wave beam formation method of the invention described above, the problem of the EBB weight vector generated frequency reduction that causes is sent at the interval that can avoid individual channel to occur, and then improves the DLBF performance of down channel.

More than being merely preferred embodiment of the present invention, is not to be used to limit protection scope of the present invention.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (8)

1. a downlink wave beam formation method is characterized in that, this method comprises:

Based on the channel impulse response that UE all up channels of all ascending time slots in current subframe is carried out said all up channels that channel estimating obtains and the signal to noise ratio snr of said all channels; Associating EBB obtains according to the EBB weight vector after the SNR merging;

Utilize said EBB weight vector after merging according to SNR, the transmission signal of the Dul sub-frame of all down channels after current subframe of said UE is carried out downlink wave beam form, said Dul is for generating the time delay of EBB weight vector;

Said basis is carried out the channel impulse response of said all up channels that channel estimating obtains and the signal to noise ratio snr of said all channels to UE all up channels of all ascending time slots in current subframe, unites EBB and comprises:

According to the SNR of said all up channels, merge the up channel impulse response of said all channels;

The covariance matrix of the said up channel impulse response signal calculated after utilize merging, and it is average that said covariance matrix is carried out recurrence, calculates the EBB weight vector according to the recurrence average result, as the EBB weight vector after merging according to SNR.

2. method according to claim 1 is characterized in that, said SNR according to all up channels, and the up channel impulse response that merges said all channels is:

According to $h_k=\frac{\underset{n=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\&Sigma;}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\&CenterDot;g_k^{k_m\left(c\left(t_n\right)\right)}\left(t_n\right)}{\underset{n=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\&Sigma;}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the channel impulse response after merging on the k root reception antenna, wherein, 0<k≤K, K are the reception antenna sum, t _n, n=1,2 ..., T is distributed with the time slot that belongs to said UE up channel, c (t _n) be at time slot t _nThe up channel numbering that belongs to said UE, C (t _n) be at time slot t _nThe up channel sum that belongs to said UE,

For said UE at time slot t _nC (t _n) channel impulse response of individual up channel, SNR (c (t _n)) be that said UE is at time slot t _nC (t _n) signal to noise ratio of individual up channel, k _m(c (t _n)) be that said UE is at time slot t _nC (t _n) the Midamble Shift that adopts of individual up channel;

Channel impulse response after merging on the every reception antenna is combined into column vector, constitutes the up channel impulse response H of said all channels.

3. method according to claim 1; It is characterized in that; Said SNR according to all up channels, the up channel impulse response that merges said all channels is: select the up channel impulse response H of the channel impulse response of the maximum up channel of SNR as said all channels after merging.

4. method according to claim 1; It is characterized in that; This method further comprises: if do not have the up channel that belongs to said UE in the current subframe; Then carry out downlink wave beam when forming at transmission signal to the Dul sub-frame after the current subframe, utilize nearest one of the current subframe of distance have the up channel that belongs to said UE subframe, generated merge according to SNR after the EBB weight vector, carry out said downlink wave beam and form.

5. a downlink wave beam formation method is characterized in that, this method comprises:

Based on the channel impulse response that UE each up channel of each ascending time slot in current subframe is carried out each up channel that channel estimating obtains; Calculate the corresponding covariance matrix of said each up channel; And it is average that each covariance matrix is carried out recurrence respectively, calculates the corresponding EBB weight vector of said each up channel based on the recurrence average result again;

According to the SNR of said each up channel, merge the corresponding EBB weight vector of said each up channel, with amalgamation result as according to the EBB weight vector after the SNR merging;

Utilize said EBB weight vector after merging according to SNR, the transmission signal of the Dul sub-frame of all down channels after current subframe of said UE is carried out downlink wave beam form, said Dul is for generating the time delay of EBB weight vector.

6. method according to claim 5 is characterized in that, said SNR according to each up channel merges the corresponding EBB weight vector of said each up channel and is:

According to $w=\frac{\underset{n=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\&Sigma;}}}\mathrm{SNR}\left(c\left(t_n\right)\right)\&CenterDot;w(c\left(t_n\right),t_n)}{\underset{n=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{c\left(t_n\right)=1}{\overset{C\left(t_n\right)}{\mathrm{\&Sigma;}}}\mathrm{SNR}\left(c\left(t_n\right)\right)}$ Calculate the corresponding EBB weight vector of each up channel, wherein, t _n, n=1,2 ..., T is distributed with the time slot that belongs to said UE up channel, c (t _n) be at time slot t _nThe up channel numbering that belongs to said UE, C (t _n) be at time slot t _nThe up channel sum that belongs to said UE, w (c (t _n), t _n) be at time slot t _nUp channel c (t _n) the EBB weight vector that generates, SNR (c (t _n)) be that said UE is at time slot t _nC (t _n) signal to noise ratio of individual up channel.

7. method according to claim 5; It is characterized in that said SNR according to each up channel merges the corresponding EBB weight vector of said each up channel and is: select the corresponding EBB weight vector of the maximum up channel of SNR as said EBB weight vector after merging according to SNR.

8. method according to claim 5; It is characterized in that; This method further comprises: if do not have the up channel that belongs to said UE in the current subframe; Then carry out downlink wave beam when forming at transmission signal to the Dul sub-frame after the current subframe, utilize nearest one of the current subframe of distance have the up channel that belongs to said UE subframe, generated merge according to SNR after the EBB weight vector, carry out said downlink wave beam and form.

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