CN103517289B - The method and apparatus determining window channel impulse response in TD-SCDMA system common frequency multi-cell - Google Patents
The method and apparatus determining window channel impulse response in TD-SCDMA system common frequency multi-cell Download PDFInfo
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Abstract
The invention discloses the method and apparatus determining window channel impulse response in a kind of TD SCDMA system same frequency multi-cell, the method includes: obtain the channel impulse response of each co-frequency cell；Intercept the local sequence of each window, slip is done relevant to reception signal, the relative position relation of the training sequence of the maximum related value position corresponding according to each window and reception signal, in the channel impulse response of respective cell, lookup and the respective reference point of respective window have the tap of identical relative position relation, if the tap found is effective, in the channel impulse response of community, each window place, determine the significance bit of the channel impulse response of respective window, and by effective tap zero setting of other windows in the significance bit of the channel impulse response of respective window, obtain the channel impulse response of respective window.Use the method or apparatus of the embodiment of the present invention, even if the channel impulse response of window can also be able to determine accurately in the case of there is exit window.
Description
Technical field
The present invention relates to mobile communication system detection technique field, particularly relate to a kind of TD-SCDMA system
The method and apparatus determining window channel impulse response in system common frequency multi-cell.
Background technology
For TD-SCDMA system, according to definition for training sequence in 3GPP standard, different little
Use different training sequences between district, between the multi-user of same community, use the difference of same basic sequence to follow
Ring shifts.Common frequency multi-cell channel estimation method implemented by receiver, it is possible to obtain the channel impulse of multiple community
Response, the different windows of each cell channel impulse response represents the different user in community.
Channel estimates to comprise initial channel estimation, channel estimates post processing two parts.Initial channel estimation obtains
The channel impulse response initial value of multiple communities, first carries out noise reduction process, then is divided by channel impulse response
It is fitted on each window.If the subscriber signal between each community and each community keeps synchronizing, then each window
The channel impulse response that mouth is corresponding can occur only in this window, in this case can be by the channel after noise reduction
Impulse response Direct Resolution is the window of K a length of W, and K is the maximum user that each community is configured
Number, W is the length of window corresponding to each user, if the asynchronous meeting time of advent of each subscriber signal
Window channel impulse response is caused to fall into other windows.Above behavior example, adjusts message by the descending time carried,
Up each user that base station receives from this community synchronizes the time of advent, and channel impulse response will not be occurred to go out
Window.But base station combination receives from the time of advent between up each user of adjacent cell asynchronous, and certain is used
The channel impulse response at family may shift to an earlier date or in the delayed channel estimation window falling into other users.Exit window can cause
Current window signal None-identified, and interference is caused for previous window or latter window.
Prior art is typically based on two kinds of situations for the consideration of exit window:
First, due to this community will not occur exit window situation only co-frequency neighbor cell receive signal there is exit window can
Can, and think that adjacent cell signal power is relatively low relative to this community, therefore exit window situation is not considered.I.e.
Do not utilize the structured message of co-frequency cell, carry out channel estimation only for this community, to simplify algorithm realization.
This method implementation complexity is low, but is not suitable for the scene that actual adjacent cell signal is stronger.
Second, by some physical layer procedure or some measured value, it is assumed that obtain co-frequency neighbor cell channel and arrive
Reaching time delay value, unified time delay of doing adjacent cell channel impulse response initial results adjusts.This method is only capable of
Time delay relation between distinguishing cell, does not differentiates between the time asynchronism between user, is therefore only applicable to descending,
It is not particularly suited for up.And the method premise is that the time knowing that adjacent cell channel reaches.
Summary of the invention
The present invention proposes to determine window channel impulse response in a kind of TD-SCDMA system common frequency multi-cell
Method and apparatus, even if also be able to determine that the channel impulse of window is rung accurately in the case of there is exit window
Should.
Technical scheme disclosed by the invention is as follows:
A kind of method determining window channel impulse response in TD-SCDMA system common frequency multi-cell, including:
Obtain the channel impulse response of each co-frequency cell；
The local sequence of each window in each co-frequency cell described in intercepting, does slip phase with receiving signal
Close, determine the maximum related value position that described each window is corresponding；
Maximum related value position according to described each window determines the state of respective window；
The training sequence ginseng of the maximum related value position corresponding according to described each window and described reception signal
The relative position relation of examination point, in the channel impulse response of community, described each window place, searches each
The tap of window；
Judge the power of the tap of described each window and the average merit of the whole channel impulse response in current area
Whether the ratio of rate is more than predetermined threshold value, if it is, determine that the tap of corresponding window is respective window
Effective tap, record the position of effective tap of described each window；
In the channel impulse response of community, each window place, determine each window with effective tap
Channel impulse response: from the position of effective tap of the window with effective tap, intercepts this window place
The chip of the length of one window length of community is as the significance bit of the channel impulse response of this window, and by this window
Effective tap zero setting of other windows in the significance bit of the channel impulse response of mouth.
Preferably, the described maximum related value position according to described each window determines the state tool of respective window
Body is:
If the maximum related value position of described window is before described training sequence reference point, it is determined that corresponding
The state of window be front exit window；If the maximum related value position of described window is in described training sequence reference
Put or in the scope of the later window length of described training sequence reference point, it is determined that the state of corresponding window
For non-exit window；If the maximum related value position of described window is at the later window of described training sequence reference point
Outside long scope, it is determined that the state of corresponding window is rear exit window.
Preferably, the local sequence of each window in each co-frequency cell described comprises respective window and is used
The Cyclic Prefix part of training sequence, and the local sequence that used of a length of respective window front several
Chip.
Preferably, described with receive signal and do slip and be related as:
The chip being separated by forward a threshold length with described training sequence reference point is initiateed as sliding window
Point, will be separated by the window length of a described window and described threshold value sum backward with described training sequence reference point
The chip of length as sliding window terminating point,
Utilize the described local sequence docking collection of letters number from the beginning of described sliding window starting point, receive signal every time
On slide backward the length of a chip, till sliding into described sliding window terminating point, often slide once
A related operation is done, it is thus achieved that corresponding correlation with receiving signal.
A kind of TD-SCDMA system common frequency multi-cell determines the device of window channel impulse response, including
Channel estimating unit, slip correlation unit, Window state determine that unit, window tap determine unit, judgement
Unit and channel impulse response determine unit,
Described channel estimating unit, is used for, it is thus achieved that the channel impulse response of each co-frequency cell；
Described slip correlation unit, is used for, the local sequence of each window in intercepting each co-frequency cell described
Row, do slip to reception signal relevant, determine the maximum related value position that described each window is corresponding；
Described Window state determines unit, is used for, and determines according to the maximum related value position of described each window
The state of respective window；
Described window tap determines unit, is used for, according to the maximum related value position that described each window is corresponding
With the relative position relation of the training sequence reference point of described reception signal, in community, described each window place
Channel impulse response in, search the tap of each window；
Described judging unit, is used for, it is judged that the power of the tap of described each window is all believed with current area
Whether the ratio of the mean power of channel shock response is more than predetermined threshold value, if it is, determine corresponding window
Effective tap that tap is respective window of mouth, records the position of effective tap of described each window；
Described channel impulse response determines unit, is used for, at the channel impulse response of community, each window place
In, determine the channel impulse response of each window with effective tap: from the window with effective tap
The effectively position of tap is risen, and intercepts the chip of length of a window length of this community, window place as this window
The significance bit of channel impulse response, and by other windows in the significance bit of the channel impulse response of this window
Effective tap zero setting.
Preferably, described Window state determine unit specifically for:
If the maximum related value position of described window is before described training sequence reference point, it is determined that corresponding
The state of window be front exit window；If the maximum related value position of described window is in described training sequence reference
Put or in the scope of the later window length of described training sequence reference point, it is determined that the state of corresponding window
For non-exit window；If the maximum related value position of described window is at the later window of described training sequence reference point
Outside long scope, it is determined that the state of corresponding window is rear exit window.
Preferably, the local sequence of each window in each co-frequency cell described comprises respective window and is used
The Cyclic Prefix part of training sequence, and the local sequence that used of a length of respective window front several
Chip.
The chip being separated by forward a threshold length with described training sequence reference point is initiateed as sliding window
Point, will be separated by the window length of a described window and described threshold value sum backward with described training sequence reference point
The chip of length as sliding window terminating point,
Preferably, described slip correlation unit specifically for:
Utilize the described local sequence docking collection of letters number from the beginning of described sliding window starting point, receive signal every time
On slide backward the length of a chip, till sliding into described sliding window terminating point, often slide once
A related operation is done, it is thus achieved that corresponding correlation with receiving signal.
Relative to prior art, the invention have the benefit that and use the Cyclic Prefix including respective window
Local sequence docking collect mail that number to do slip from sliding window starting point to sliding window terminating point relevant, by maximum
Tap corresponding on the channel impulse response of community, correlation location lookup respective window place, if this tap
For effective tap, then determine the channel impulse response of respective window according to the position of this tap, the most shortly
It also is able to determine accurately the channel impulse response of window in the case of making generation exit window.
Except above beneficial effect, the present invention also has beneficial effect: the present invention is for the tap of each window
The most effectively judged, by calculating the power of tap of each window and community, respective window place
Mean power carries out odds ratio relatively, is effective tap more than the tap of the corresponding window of predetermined threshold value, this
Sample can reduce effect of noise, improves the accuracy that exit window judges.
Except above beneficial effect, the present invention also has beneficial effect: the present invention only receives letter to current time slots
Number process the channel impulse response that just can determine respective window accordingly, it is not necessary to other physical processes
Assistance, it is not required that introduce the interface of new parameter and other modules and joint-detection module, it is achieved complicated
Spend low, and real-time is good, adapt to the actual application scenarios that location of mobile station is continually changing.
Except above beneficial effect, the present invention also has beneficial effect: the present invention obtains having of each community
Effectively after the window of tap, determine the significance bit of the channel impulse response of the window with effective tap, and will
Effective tap zero setting of other windows in significance bit, it is ensured that only include in the channel impulse response of each window
Each effective tap of window, disturbing mutually between adjacent window before and after can avoiding.
Except above beneficial effect, the present invention also has beneficial effect: the present invention is based on slip correlation, sliding
Dynamic correlation peak is sharp-pointed, and sliding window length is less, and memory data output is low, it is achieved simple.
Accompanying drawing explanation
Fig. 1 is the structural representation of burst in TD-SCDMA system；
Fig. 2 is the structural representation of the Midamble code of the different windows use of same community；
Fig. 3 is the flow chart of steps of the inventive method embodiment；
Fig. 4 is that the inventive method embodiment utilizes the local sequence docking collection of letters number to make the relevant schematic diagram that slides；
Fig. 5 is that the inventive method embodiment determines the tap of window according to the maximum related value position of window
The schematic diagram of position；
Fig. 6 is that the inventive method embodiment determines the channel punching of window according to the position of effective tap of window
Swash the schematic diagram of response significance bit；
Fig. 7 is the structural representation of apparatus of the present invention embodiment.
Detailed description of the invention
The present invention proposes to determine window channel impulse response in a kind of TD-SCDMA system common frequency multi-cell
Method and apparatus, even if also be able to determine that the channel impulse of window is rung accurately in the case of there is exit window
Should.
Burst is structure most basic in TD-SCDMA system, as it is shown in figure 1, a burst is by two sections
The data division of 352chips and the Midamble code part of 144chips and protection interval GP form.Root
According to definition for training sequence in 3GPP standard, between the different community in TD-SCDMA system
Use the basic code of different training sequences (Midamble), use same between the different user of same community
The Midamble code that the different cyclic shifts of one Midamble basic code construct.Each community is not
The different user in community is shown with Window Table.
The structure of the Midamble code that the different windows of same community uses is as in figure 2 it is shown, according to i-th
The Midamble basic code that community uses constructs the different window in i-th community by the way of cyclic shift
The Midamble code that mouth uses.Set maximum user number K that i-th community is configuredi, Ze Gai community
In the window length of each window be Wi=P/KI, the Midamble1 of first window in this community is little by this
The a length of W of final stage of the Midamble basic code in districtiX1 as Cyclic Prefix, Bing Yugai community
Midamble basic code before a part collectively constitute so that it is overall length is 144, in this community
Last two segment length of the Midamble basic code of this community are W by the Midamble2 of two windowsi
X2 and X1 as Cyclic Prefix, before the Midamble basic code of Bing Yugai community, another part is altogether
With composition so that it is overall length is 144, can get what each window in i-th community was used by that analogy
Midamble code.
The feature of the Midamble code of different windows based on each community constructed above, the present invention proposes
In method, each in the burst (hereinafter referred to receiving signal) of the time slot received according only to receiving terminal
The feature of individual Midamble code determines the channel impulse response of each window in each co-frequency cell, no
Need the assistance of other physical processes, it is not required that introduce new parameter and other modules and joint-detection module
Interface, it is achieved complexity is low, and real-time is good, adapts to the actual application that is continually changing of location of mobile station
Scene.
Shown in Figure 3, Fig. 3 is the flow chart of the inventive method embodiment, the present embodiment can include as
Lower step:
Step 301: obtain the channel impulse response of each co-frequency cell；
The burst of the time slot that receiving terminal receives may include the signal from each co-frequency cell,
Utilize the Midamble basic code of all co-frequency cells known to receiving terminal and receive signal acquisition reception signal
In the channel impulse response of each co-frequency cell that relates to, determine receive the co-frequency cell that relates in signal
Number is n, and the channel impulse response of each community includes P=128 chip；
If the subscriber signal between each community and each community keeps synchronizing, the channel that each window is corresponding
Impulse response can occur only in this window, receives in signal and in this case can be rushed by the channel after noise reduction
Swashing response Direct Resolution is KjIndividual a length of WjWindow, wherein, j=1,2 ... n；KjJoined for jth community
The maximum number of users put, WjLong for window: Wj=P/Kj.If but each subscriber signal is different for the time of advent
Step, it may occur that exit window problem causes window aliasing.Exit window refers to cause window channel to rush owing to reaching time irreversibility
Sharp response falls into the situation of other windows.So the channel impulse response of the i-th community for obtaining can not be straight
Connect and be decomposed into KjIndividual a length of WjWindow.
Step 302: intercepting the local sequence of each window, it is relevant that slip is done in the docking collection of letters number, determines each
The maximum related value position that window is corresponding.
Sliding relevant is to choose sliding window on the received signal, determines slip starting point and sliding window terminating point,
Then for each window, utilize the local sequence of this window from the sliding window of the sliding window receiving signal
Initial point starts, and slides backward the length of a chip the most on the received signal, until sliding into sliding window eventually
Till stop, and often slide once will with receive signal do a related operation, it is thus achieved that with this window pair
Each correlation answered.The related operation of two sequences reflects the similarity degree of two signals, two sequences
The most similar, correlation is the biggest.
The local sequence of each window is that the Midamble code by being configured each window is chosen
, the intercepting starting point of the local sequence of each window and length, being to ensure that can be by the basis of respective window
Ground sequence carries out, to receiving signal, the relevant correlation result the obtained channel impulse sound in respective cell that slides
The basis of the tap of each window is found in Ying.
Utilize the local sequence of each window to receive signal and carry out slide relevant before, in this case it is not apparent that reception
Whether including the signal of the Midamble code that have employed this window in signal, Fig. 4 assumes that reception signal
In include three kinds of situations of signal of the Midamble code that have employed window 2, because the purpose of the present invention
It is the local sequence choosing respective window according to known all window Midamble codes, and believes with receiving
Number do slip relevant, determine the channel impulse response receiving all windows comprised in signal.So with scheming
Window 2 in 4 illustrates to illustrate the selection principle of the local sequence of window, and this selection principle is also suitable
To corresponding window in time receiving the signal not comprising the Midamble code that have employed some window in signal
The choosing of local sequence.
2 points are considered: the first point, the local sequence of each window needs to comprise respective window when choosing
The Cyclic Prefix part of Midamble code, as shown in Figure 4, includes window 2 in the local sequence of window 2
Cyclic Prefix X2 and X1.So, when the utilization local sequence docking collection of letters number is done and is slided relevant, can
To determine the Midamble code receiving window corresponding with corresponding local sequence in signal more accurately
Original position.Second point, intercepts several symbols front of Midamble code of each window as accordingly
The local sequence of window rather than take the chip of whole length of Midamble code of each window as phase
Answer the local sequence of window.In Fig. 4, the intercepted length of the local sequence of window 2 is 128.If window 2
The length of the local sequence Midamble code that is chosen for window 2 whole length 144 if, then profit
Carry out sliding with the local sequence docking collection of letters number of window 2 and be correlated with in the result of each correlation obtained, no
Only in the original position of window 2, (situation one of Fig. 4 is the situation that window 2 occurs front exit window, represents window
The original position of 2 uses arrow logo the most in the diagram) there is theoretic maximum related value, namely
There is when the X2 part of the local sequence of window 2 is with the X2 section aligned of window 2 theoretic maximum phase
Pass is worth, referred to as real peak, and, the local sequence at window 2 starts to slide backward from sliding window starting point
During, also there will be when the X1 part of local sequence of window 2 is with the X1 section aligned of window 1
Bigger correlation, referred to as ghost peak, the two correlation difference is less, is difficult to differentiate under effect of noise.As
Fruit is by the local sequence truncation of window 2, then the numerical difference between ghost peak and real peak, away from increasing, is conducive to
The detection of real peak.If the local sequence of window 2 only intercepts X2 part, then utilize this locality of window 2
Sequence docking collect mail number carry out sliding relevant each correlation obtained result in ghost peak would not occur, but
It it is if the length of the local sequence of window 2 is too short, then antinoise when carrying out sliding relevant to reception signal
Ability can be decreased obviously.Therefore, the length of local sequence is chosen and should be considered noiseproof feature and suppression
The characteristic of ghost peak.
As shown in Figure 4, generally, the state receiving all windows in signal can be divided into three kinds of feelings
Condition, the window of exit window before occurring, occur after the window of exit window and the window of exit window does not occur, but for
For one window, the burst of a time slot can be only in one of which state.In order to detect
The window of various states, receive the sliding window on signal chooses that be also to ensure that can be by the basis of respective window
Ground sequence carries out, to receiving signal, the relevant correlation result the obtained channel impulse sound in respective cell that slides
The key of the tap of each window is found in Ying.
In embodiments of the invention 1, shown in Figure 4, with receive in signal Midamble part
Starting point, as Midamble reference point, namely receives first code of the Midamble part of signal
The position of sheet is as Midamble reference point, and sliding window starting point is to take forward in Midamble reference point
The data chips of one threshold length, sets this threshold value as Y, and the value of Y should ensure that sliding window starting point
Comprising the original position of the window of the front exit window of the generation in all communities backward, the situation one of Fig. 4 is window 2
The situation of exit window before occurring, the original position of window 2 has used arrow logo；Sliding window is eventually
Stop is to have taken with Midamble reference point in Midamble reference point that to be separated by the window of a window long backward
Individual with the Midamble chip of the length of a threshold value sum, i.e. distance Midamble reference point W+Y long
Degree, thus the value of Y also should ensure that sliding window terminating point comprise forward all communities occur after exit window
The original position of window, the situation three in Fig. 4 is the situation of exit window after window 2 occurs, initiateing of window 2
Position has used arrow logo.
After sliding window in local sequence and reception signal determines, implementing slip relevant, sliding window is a length of
W+2Y.Generally, the exit window length of a window not over the length of a window, so,
In the present embodiment 1, the value of Y is set to a long W of window, so the total length of sliding window is window
Long three times, i.e. sliding window length are equal to 3W.The local sequence docking collection of letters number utilizing each window is slided
Dynamic relevant, all can obtain 3W correlation, find the maximum related value of each window, and record each
The maximum related value of window is relative to the maximal correlation of the position of Midamble reference point, referred to as respective window
Value position.The peak value of the maximum related value of each window is general the most sharp-pointed, and receives and choose on signal
Sliding window length is less, and memory data output is low, it is achieved simple.
If reception signal includes the signal of the Midamble code that have employed some window, then profit
Carry out slip by the local sequence of this window to reception signal relevant, have in 3W the correlation obtained
One particularly apparent sharp-pointed correlation occurs, this particularly apparent sharp-pointed correlation is this 3W
Maximum in correlation, records the maximum related value position relative to Midamble reference point of this window.
As shown in Figure 4, if receiving the signal including the Midamble code using window 2 in signal, then
In the case of which kind of window of tube 2 is not in, the maximum related value of window 2 be both present in corresponding in the case of window
The original position of 2.
If reception signal not comprising the signal of the Midamble code that have employed some window, due to meeting
Noisy interference, then utilize the local sequence of this window to carry out slip to reception signal relevant, also can obtain
3W the correlation arrived, the most also has maximum correlation and occurs, also records this window
Big correlation is relative to the position of Midamble reference point.
Step 303: determine the state of respective window according to the maximum related value position of each window；
If the maximum related value position of each window with effective tap of record exists in step 302
Before Midamble reference point, then corresponding window there occurs front exit window；See situation one in Fig. 5, as
The maximum related value position of the window 2 really recorded in step 302 is before Midamble reference point, then
It is assured that window 2 there occurs front exit window；Now the maximum related value position of window 2 is at Midamble
Before reference point, and the distance of one exit window lead of distance Midamble reference point, generally,
Before occurring, the exit window length of the window of exit window is long not over a window, so this exit window lead meets: 0 ＜
Exit window lead≤W.
If the maximum related value position of each window with effective tap of record is just in step 302
In the position of Midamble reference point, then there is not exit window in corresponding window；It is contemplated that wireless communication
The delay character in road, if so maximum phase of each window with effective tap recorded in step 302
Value position, pass is after Midamble reference point, as long as in the later window length of Midamble reference point
In the range of, then can also determine that corresponding window does not occur exit window；See situation two in Fig. 5, if
In step 302, the maximum related value position of the window 2 of record is after Midamble reference point, and distance
The distance of one exit window retardation 1 of Midamble reference point, and this exit window retardation 1 is satisfied: and 0 ＜ goes out
Window retardation 1 ＜ W, then can also determine that window 2 does not occur exit window,
If the maximum related value position of each window with effective tap of record exists in step 302
Outside the scope of the later window length of Midamble reference point, then corresponding window there occurs rear exit window；Ginseng
See situation three in Fig. 5, if the maximum related value position of the window 2 of record is at Midamble in step 302
After reference point, and the distance of one exit window retardation 2 of distance Midamble reference point, and this exit window
Retardation meets: W≤exit window retardation 2, then be assured that window 2 there occurs rear exit window.Typically
In the case of, after generation, to be not more than a window long for the exit window length of the window of exit window, so this exit window postpones
Amount 2 meets: W≤exit window lead ＜ 2W.
Step 304: according to maximum related value position and the phase para-position of Midamble reference point of each window
Put to close and tie up to search on the channel impulse response of community, each window place the tap corresponding with each window；
As it is shown in figure 5, for the window 2 in a community, it is known that the maximum number of user in this community is K
With the channel impulse response of this community a length of 128, it is first assumed that all windows in this community all do not have
Exit window occurs, and the channel impulse response Direct Resolution of Xian Jianggai community is the original window of K a length of W,
W=128/K.Previous window that each window in this community is adjacent with this window and adjacent later window
Mouth adjacent window each other, and first window of this community and last window adjacent window, namely window K each other
It it is the previous window of the window 1 adjacent with window 1.
Maximum related value position according to window 2 and the relative position relation of Midamble reference point, at this
The tap that in the channel impulse response of community, lookup is corresponding with window 2:
See situation one in Fig. 5, if the maximum related value position of the window 2 of record exists in step 302
Before Midamble reference point, and the distance of one exit window lead of distance Midamble reference point, and should
Exit window lead meets: 0 ＜ exit window lead≤W, then at the channel impulse response of community, window 2 place
On, using the starting point of the original window 2 of window 2 correspondence as the reference point of window 2 oneself, referred to as window
2 reference points (at the circular stain in the situation one of Fig. 5), the original window 2 before window 2 reference point
Previous window original window 1 in, the distance identical exit window lead distance of window 2 reference point one
Tap corresponding to position seeks to the tap of window 2 correspondence searched, the referred to as tap of window 2；
If the maximum related value position of each window with effective tap of record is just in step 302
Position in Midamble reference point, then on the channel impulse response of community, window 2 place, at window
Tap corresponding to the position of mouthful 2 reference points is exactly the tap of window 2；
See situation two in Fig. 5, if the maximum related value position of the window 2 of record exists in step 302
After Midamble reference point, and the distance of one exit window retardation 1 of distance Midamble reference point, and
And this exit window retardation 1 meets: 0 ＜ exit window retardation 1 ＜ W, then at the channel of community, window 2 place
On impulse response, in the original window 2 after window 2 reference point, distance one phase of window 2 reference point
With tap corresponding to the position of distance of exit window retardation 1 be exactly the tap of window 2；
See situation three in Fig. 5, if the maximum related value position of the window 2 of record exists in step 302
After Midamble reference point, and the distance of one exit window retardation 2 of distance Midamble reference point, and
And this exit window retardation meets: W≤exit window retardation 2, then in the channel impulse of community, window 2 place
In response, in the later window original window 3 of the original window 2 after window 2 reference point, distance
The tap that the position of the distance of the exit window retardation 2 that window 2 reference point one is identical is corresponding is exactly window 2
Tap.
Step 305: judge whether the tap that each window in each co-frequency cell is corresponding is respective window
Effectively tap, if it is, enter step 306；
In this step, if receiving the letter comprising, in signal, the Midamble code that have employed some window
Number, then the relevant maximum related value obtained of sliding is done in the local sequence docking collection of letters number according to utilizing this window
The tap of this window found is exactly effective tap of this window；Have employed if reception signal does not comprise
The signal of the Midamble code of some window, then the local sequence docking according to utilizing this window is collected mail
The tap number making this window that the relevant maximum related value obtained of sliding finds is exactly to receive making an uproar in signal
The tap that sound produces.
In a particular embodiment of the present invention, it is judged that the effectively step of tap is as follows:
Step A1: calculate the power of the tap of each window；
Step A2: make to compare by the mean power of whole to the power of this tap and current area channel impulse responses
Value；
Step A3: judge that this ratio, whether more than a pre-determined threshold, if greater than pre-determined threshold, then should
Tap is effective tap of respective window.
So finding all windows with effective tap in each co-frequency cell, labelling is each to be had has
The window of effect tap, and record effective tap of each window position on the channel impulse response of current area
Put.
In this step, if it should be noted that the judged result of step 305 is no, then stop current
Flow process.
Step 306: determine each window with effective tap in the channel impulse response of each community
Channel impulse response；
For each community, through above step, had learned that in each community all have effectively take out
The window of head and effective tap position on the channel impulse response of current area thereof, then effectively take out with this
The position of head is starting point, chooses the chip of length of a window length backward as the channel impulse of respective window
The significance bit of response, and by effective tap of other windows in the significance bit of the channel impulse response of this window
Zero setting.
Window 2 in corresponding diagram 4 and Fig. 5, it is determined that window 2 has effective tap, as shown in Figure 6,
Which kind of situation not there is in window of tube 2, is all in the current area at window 2 place by effective tap of window 2
Channel impulse response on position as the starting point of the significance bit of the channel impulse response of window 2, from this
Starting point chooses the chip significance bit as the channel impulse response of window 2 of the length of a window length backward
Terminating point, then the significance bit of the channel impulse response of window 2 just can determine that.
If the position of effective tap of window 2 falls on original window 1, such as the situation one in Fig. 6, that
If also including the effective of window 1 in the significance bit of the channel impulse response of the window 2 obtained before
Tap, then effective tap zero setting of window 1 in the significance bit of the channel impulse response of window 2 should be protected
Card only comprises effective tap of window 2 oneself in window 2；If the channel impulse response of window 1 has
Effect position also comprises the tap of window 2, then should be by window in the significance bit of the channel impulse response of window 1
Effective tap zero setting of 2, it is ensured that only comprise effective tap of window 1 oneself in window 1.
If the position of effective tap of window 2 falls on original window 3, such as the situation three in Fig. 6, that
If also including window 3 even window in the significance bit of the channel impulse response of the window 2 obtained before
Mouth 4 (position of the original window 4 of window 4 correspondence, after original window 3, is shown without in figure 6)
Effective tap, then should be by the even window 4 of window 3 in the significance bit of the channel impulse response of window 2
Effective tap zero setting, it is ensured that in window 2, only comprise effective tap of window 2 oneself；If window 3
Channel impulse response significance bit in also comprise the tap of window 2, then should be by the channel impulse of window 3
Effective tap zero setting of window 2 in the significance bit of response, it is ensured that only comprise window 3 oneself in window 3
Effectively tap；A general window is only possible to fall in the previous window adjacent with it exit window before generation, or
Person falls exit window after occurring in the later window adjacent with it, will not fall the feelings in other window
Condition, so the significance bit of the channel impulse response in window 4 will not comprise effective tap of window 2, because of
This is disturbing between adjacent window mutually before and after can being avoided by the method for the present invention.
The embodiment of the invention also discloses in a kind of TD-SCDMA system common frequency multi-cell and determine window channel
The device of impulse response, with reference to shown in Fig. 7, for the structural representation of device embodiment, the dress of the present embodiment
Put and specifically may include that and include that channel estimating unit 701, slip correlation unit 702, Window state determine
Unit 703, window tap determine that unit 704, judging unit 705 and channel impulse response determine unit 706,
Described channel estimating unit 701, is used for, it is thus achieved that the channel impulse response of each co-frequency cell；
Described slip correlation unit 702, is used for, the basis of each window in intercepting each co-frequency cell described
Ground sequence, does slip to reception signal relevant, determines the maximum related value position that described each window is corresponding；
Preferably, described slip correlation unit concrete 702 specifically may be used for:
The chip being separated by forward a threshold length with described training sequence reference point is initiateed as sliding window
Point, will be separated by the window length of a described window and described threshold value sum backward with described training sequence reference point
The chip of length, as sliding window terminating point, utilizes the described local sequence docking collection of letters number from described sliding window
Initial point starts, and slides backward the length of a chip the most on the received signal, until sliding into described slip
Till window terminating point, often slide and once do a related operation with reception signal, it is thus achieved that corresponding correlation.
Described Window state determines unit 703, is used for, according to the maximum related value position of described each window
Determine the state of respective window；
Described Window state determine unit 703 specifically for: if the maximum related value position of described window exists
Before described training sequence reference point, it is determined that the state of corresponding window is front exit window；If described window
Maximum related value position in described training sequence reference point or in the later of described training sequence reference point
In the scope of window length, it is determined that the state of corresponding window is non-exit window；If the maximal correlation of described window
Value position is outside the scope of the later window length of described training sequence reference point, it is determined that the shape of corresponding window
State is rear exit window；
Described window tap determines unit 704, is used for, according to the maximum related value that described each window is corresponding
The relative position relation of the training sequence reference point of position and described reception signal, at described each window place
In the channel impulse response of community, search the tap of each window；
Described judging unit 705, is used for, it is judged that the power of the tap of described each window is complete with current area
Whether the ratio of the mean power of portion's channel impulse response is more than predetermined threshold value, if it is, determine corresponding
Effective tap that tap is respective window of window, record the position of effective tap of described each window；
Described channel impulse response determines unit 706, is used for, in the channel impulse of community, each window place
In response, determine the channel impulse response of each window with effective tap: from the window with effective tap
The position of effective tap of mouth is risen, and intercepts the chip of length of a window length of this community, window place as this
The significance bit of the channel impulse response of window, and by other in the significance bit of the channel impulse response of this window
Effective tap zero setting of window.
Preferably, the local sequence of each window in each co-frequency cell described comprises respective window and is used
The Cyclic Prefix part of training sequence, and the local sequence that used of a length of respective window front several
Chip.
Use device disclosed in the embodiment of the present invention, disturbing mutually between adjacent window before and after can avoiding.
Below it is only the preferred embodiment of the present invention, it is noted that common for the art
For technical staff, on the premise of without departing from the principle of the present invention, it is also possible to make some improvement and
Retouching, these improvements and modifications also should be regarded as protection scope of the present invention.
Claims (4)
1. the method determining window channel impulse response in TD-SCDMA system common frequency multi-cell,
It is characterized in that, including:
Obtain the channel impulse response of each co-frequency cell；
The local sequence of each window in each co-frequency cell described in intercepting, does slip phase with receiving signal
Close, determine the maximum related value position that described each window is corresponding；Wherein, in each co-frequency cell described
The local sequence of each window comprises the Cyclic Prefix part of the training sequence that respective window is used, and length
By several chips before the local sequence that respective window is used；Described to receive signal do slip relevant
For: the chip being separated by forward a threshold length with described training sequence reference point is initiateed as sliding window
Point, will be separated by the window length of a described window and described threshold value sum backward with described training sequence reference point
The chip of length is as sliding window terminating point；Utilize the described local sequence docking collection of letters number from described sliding window
Initial point starts, and slides backward the length of a chip the most on the received signal, until sliding into described slip
Till window terminating point, often slide and once do a related operation with reception signal, it is thus achieved that corresponding correlation；
Maximum related value position according to described each window determines the state of respective window；
The training sequence ginseng of the maximum related value position corresponding according to described each window and described reception signal
The relative position relation of examination point, in the channel impulse response of community, described each window place, searches each
The tap of window；
Judge the power of the tap of described each window and the average merit of the whole channel impulse response in current area
Whether the ratio of rate is more than predetermined threshold value, if it is, determine that the tap of corresponding window is respective window
Effective tap, record the position of effective tap of described each window；
In the channel impulse response of community, each window place, determine each window with effective tap
Channel impulse response: from the position of effective tap of the window with effective tap, intercepts this window place
The chip of the length of one window length of community is as the significance bit of the channel impulse response of this window, and by this window
Effective tap zero setting of other windows in the significance bit of the channel impulse response of mouth.
Method the most according to claim 1, it is characterised in that
The described maximum related value position according to described each window determine respective window state particularly as follows:
If the maximum related value position of described window is before described training sequence reference point, it is determined that corresponding
The state of window be front exit window；If the maximum related value position of described window is in described training sequence reference
Put or in the scope of the later window length of described training sequence reference point, it is determined that the state of corresponding window
For non-exit window；If the maximum related value position of described window is at the later window of described training sequence reference point
Outside long scope, it is determined that the state of corresponding window is rear exit window.
3. TD-SCDMA system common frequency multi-cell determines a device for window channel impulse response,
It is characterized in that, determine that unit, window are taken out including channel estimating unit, slip correlation unit, Window state
Head determines that unit, judging unit and channel impulse response determine unit,
Described channel estimating unit, is used for, it is thus achieved that the channel impulse response of each co-frequency cell；
Described slip correlation unit, is used for, the local sequence of each window in intercepting each co-frequency cell described
Row, do slip to reception signal relevant, determine the maximum related value position that described each window is corresponding；Described
The local sequence of each window in each co-frequency cell comprises following of the training sequence that respective window used
Ring prefix part, and several chips front of local sequence that a length of respective window is used；Described slip
Correlation unit specifically for: will be separated by forward with described training sequence reference point a threshold length chip make
For sliding window starting point, window length and the institute of a described window will be separated by backward with described training sequence reference point
State the chip of length of threshold value sum as sliding window terminating point, utilize described local sequence docking collect mail number from
Described sliding window starting point starts, and slides backward the length of a chip the most on the received signal, until sliding
Till moving described sliding window terminating point, often slide and once do a related operation with reception signal, it is thus achieved that phase
The correlation answered；
Described Window state determines unit, is used for, and determines according to the maximum related value position of described each window
The state of respective window；
Described window tap determines unit, is used for, according to the maximum related value position that described each window is corresponding
With the relative position relation of the training sequence reference point of described reception signal, in community, described each window place
Channel impulse response in, search the tap of each window；
Described judging unit, is used for, it is judged that the power of the tap of described each window is all believed with current area
Whether the ratio of the mean power of channel shock response is more than predetermined threshold value, if it is, determine corresponding window
Effective tap that tap is respective window of mouth, records the position of effective tap of described each window；
Described channel impulse response determines unit, is used for, at the channel impulse response of community, each window place
In, determine the channel impulse response of each window with effective tap: from the window with effective tap
The effectively position of tap is risen, and intercepts the chip of length of a window length of this community, window place as this window
The significance bit of channel impulse response, and by other windows in the significance bit of the channel impulse response of this window
Effective tap zero setting.
Device the most according to claim 3, it is characterised in that described Window state determines that unit has
Body is used for:
If the maximum related value position of described window is before described training sequence reference point, it is determined that corresponding
The state of window be front exit window；If the maximum related value position of described window is in described training sequence reference
Put or in the scope of the later window length of described training sequence reference point, it is determined that the state of corresponding window
For non-exit window；If the maximum related value position of described window is at the later window of described training sequence reference point
Outside long scope, it is determined that the state of corresponding window is rear exit window.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101022285A (en) * | 2007-03-20 | 2007-08-22 | 中兴通讯股份有限公司 | Co-channel adjacent cell channel estimating method at the time of multi-cell union detection in TD SCDMA system |
| DE60127932T2 (en) * | 2001-02-27 | 2008-04-03 | Freescale Semiconductor, Inc., Austin | Channel estimation in systems with orthogonal frequency division multiplexed signals |
| CN101252554A (en) * | 2008-01-08 | 2008-08-27 | 北京天碁科技有限公司 | Method and apparatus for postprocessing channel estimation |
| CN101499845A (en) * | 2008-01-29 | 2009-08-05 | 大唐移动通信设备有限公司 | Uplink synchronous detection method and apparatus for TD-SCDMA system |
-
2012
- 2012-06-21 CN CN201210212401.4A patent/CN103517289B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60127932T2 (en) * | 2001-02-27 | 2008-04-03 | Freescale Semiconductor, Inc., Austin | Channel estimation in systems with orthogonal frequency division multiplexed signals |
| CN101022285A (en) * | 2007-03-20 | 2007-08-22 | 中兴通讯股份有限公司 | Co-channel adjacent cell channel estimating method at the time of multi-cell union detection in TD SCDMA system |
| CN101252554A (en) * | 2008-01-08 | 2008-08-27 | 北京天碁科技有限公司 | Method and apparatus for postprocessing channel estimation |
| CN101499845A (en) * | 2008-01-29 | 2009-08-05 | 大唐移动通信设备有限公司 | Uplink synchronous detection method and apparatus for TD-SCDMA system |
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