CN103312648A - Method and device for synchronization offset estimation of communication system, mobile terminal and base station - Google Patents

Abstract

Disclosed are a method and a device for synchronization offset estimation of a communication system as well as a mobile terminal and a base station. The method for synchronization offset estimation of the communication system comprises the steps of carrying out R-time oversampling on a channel estimation result of a signal; acquiring an estimated position and power of a strongest path of the signal and an estimated position and power of a secondly strongest path of the signal based on the channel estimation result after R-time oversampling; and determining synchronization offset of the system at least based on the estimated position of the strongest path and a target position of a synchronization point according to the relationship between the power of the strongest path and the power of the secondly strongest path. The technical scheme of the invention can well adapt to wireless channel environments such as a mobile channel and a birth-and-death channel to obtain good system performance without affecting the performance under a common channel.

Description

The simultaneous bias method of estimation of communication system and device, portable terminal and base station

Technical field

The present invention relates to the communications field, particularly a kind of simultaneous bias method of estimation of communication system and device, portable terminal and base station.

Background technology

In mobile communication system, need to guarantee transmitting terminal and receiving terminal sampling clock synchronously.Because the operation of subscriber equipment (UE, User Equipment) and the deviation of crystal oscillator may cause the sending and receiving end clock deviation to occur, UE need to be by regularly keeping synchronously.Therefore, sampling clock has become important component in the associated communication system synchronously, and an important part is exactly accurately to estimate the sampling clock offset that exists in the communication system in the clock synchronous.

The simultaneous bias of communication system is estimated common interpolation method based on channel estimating; its basic principle is that the channel estimation results with signal carries out R times of over-sampling; R depends on the demand to estimated accuracy, then chooses the moment corresponding to the strongest path of signal as optimum sampling constantly.The estimated accuracy of this method depends on the multiple of over-sampling, and for example, if carried out 8 times of over-samplings, the synchronism deviation estimated accuracy that obtains so is 1/8 chip (chip).

Channel estimation results for each subframe, all can adopt said method to obtain the estimated position in the strong path of a signal under certain estimated accuracy requires, this estimated position just can be used as the synchronous point position, and the difference between itself and the synchronous point target location is the simultaneous bias of system.

Although the simultaneous bias method of estimation of this routine; under common channel circumstance, good systematic function can be arranged; but giving birth under the wireless channel environments such as channel and mobile channel that go out, often can be relatively poor because of the inaccurate systematic function that causes of simultaneous bias estimated result.In order to keep the transmission performance under the conventional channel and to can be good at supporting giving birth to go out channel and mobile channel, need to the method that simultaneous bias is estimated be optimized and improve.

Correlation technique can be the U.S. Patent application of US2011122979 (A1) with reference to publication number also, this Patent Application Publication a kind of sampling clock offset estimation and compensation method and device.

Summary of the invention

The problem to be solved in the present invention is that prior art is difficult to adapt to giving birth to the simultaneous bias estimation of communication system under the wireless channel environments such as channel and mobile channel that go out, to obtain preferably systematic function.

For addressing the above problem, technical solution of the present invention provides a kind of simultaneous bias method of estimation of communication system, comprising:

Channel estimation results to signal carries out R times of over-sampling;

Based on the channel estimation results behind the R times of over-sampling, obtain estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal;

According to the relation between the power in the power in the strongest path and time strong path, determine at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.

Optionally, described channel estimation results to signal carries out R times of over-sampling and comprises:

Channel estimation results to signal carries out R ₁Times interpolation;

With described R ₁Channel estimation results after times interpolation is determined the strongest path of signal and the interval that time strong path occurs;

Respectively the strongest described path and time strong path occur interval in to described R ₁Channel estimation results after times interpolation carries out R ₂Times interpolation; Wherein, R ₁* R ₂=R.

Optionally, described based on the channel estimation results behind the R times of over-sampling, the estimated position and the power that obtain time strong path of the estimated position in the strongest path of signal and power and signal comprise:

From described to R ₁Obtain described the first estimated value L ' of the estimated position in strong path in the channel estimation results after times interpolation _MaxWith described inferior by force the first estimated value V ' of the estimated position in path _Max

From described to R ₁Channel estimation results after times interpolation carries out R ₂Obtain described the second estimated value L of the estimated position in strong path among the result after times interpolation " _MaxWith power and described inferior by force the second estimated value V of the estimated position in path " _MaxAnd power;

With R ₂* L ' _MaxWith L " _MaxSum is as the described estimated position in strong path, with R ₂* V ' _MaxWith V " _MaxSum is as the estimated position in described strong path.

Optionally, described with described R ₁Channel estimation results after times interpolation determines that the interval that time strong path occurs of signal comprises:

At described R ₁In the channel estimation results after times interpolation, N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty; Wherein N sets based on channel circumstance;

Based on the channel estimation results that empties after the described data, determine the interval that time strong path occurs of signal.

Optionally, R=16, R ₁=2, R ₂=8.

Optionally, described basis is the relation between the power in the power in strong path and time strong path, determines that based on the estimated position in described the strongest path and the target location of synchronous point the simultaneous bias of system comprises at least:

Judge that whether the power in described strong path is greater than threshold value, be then with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point, otherwise with the difference of the target location of the estimated position in described the strongest path and the described synchronous point simultaneous bias as system; Described threshold value is the described power in strong path and the product of threshold parameter.

Optionally, the span of described threshold parameter be [1/2,1).

Optionally, described with described the strongest path the estimated position and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point comprise:

With the described estimated position L in strong path _PeakEstimated position V with described strong path _PeakBetween centre position T ₀Determine the shifted by delta L of integral multiple chip _Int

With the described estimated position L in strong path _PeakTarget location L with described synchronous point _TrgtCalculate decimal times chip offset Δ L _Frac

With described integral multiple chip offset Δ L _IntWith decimal times chip offset Δ L _FracSum is as the simultaneous bias of system.

Optionally, described integral multiple chip offset Δ L _Int=T _{0, int}-L _Trgt, wherein:

T ₀=round ((L _Peak+ V _Peak)/2), round is the round function; Described decimal times chip offset Δ L _Frac=mod (L _Peak-L _Trgt, R), wherein mod is MOD function.

Optionally, described over-sampling is realized by raised cosine roll off filter or low pass filter.

Optionally, described communication system is the TD-SCDMA communication system.

For addressing the above problem, technical solution of the present invention also provides a kind of simultaneous bias estimation unit of communication system, comprising:

The over-sampling unit is suitable for the channel estimation results of signal is carried out R times of over-sampling;

Acquiring unit is suitable for based on the channel estimation results behind the R times of over-sampling, obtains estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal;

The simultaneous bias determining unit is suitable for according to the relation between the power in the power in the strongest path and path time by force, determines at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.

For addressing the above problem, technical solution of the present invention also provides a kind of portable terminal and a kind of base station that comprises the simultaneous bias estimation unit of above-mentioned communication system that comprises the simultaneous bias estimation unit of above-mentioned communication system.

Compared with prior art, technical solution of the present invention has the following advantages:

Channel estimation results to signal carries out over-sampling, obtain estimated position and the power in the strongest path and the inferior strong path of signal the result behind over-sampling, again according to the relation between the power in the power in described the strongest path and described strong path, at least determine the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point, so, determine that by estimating two the strongest paths of signal the synchronous point position can estimate the simultaneous bias of system exactly, thereby can well adapt to the wireless channel environments such as mobile channel and the living channel that goes out, obtain preferably systematic function, and do not affect the performance under the conventional channel.

Description of drawings

Fig. 1 is the schematic flow sheet of the simultaneous bias method of estimation of the communication system that provides of embodiment of the present invention;

Fig. 2 is the clock skew schematic diagram of communication system under the mobile propagation conditions;

Fig. 3 is the clock skew schematic diagram of giving birth to communication system under the propagation conditions that goes out;

Fig. 4 is the structural representation of the simultaneous bias estimation unit of the communication system that provides of the embodiment of the invention.

Embodiment

For above-mentioned purpose of the present invention, feature and advantage can more be become apparent, below in conjunction with accompanying drawing the specific embodiment of the present invention is described in detail.Set forth detail in the following description so that fully understand the present invention.But the present invention can be different from alternate manner described here and implements with multiple, and those skilled in the art can be in the situation that do similar popularization without prejudice to intension of the present invention.Therefore the present invention is not subjected to the restriction of following public embodiment.

Fig. 1 is the schematic flow sheet of the simultaneous bias method of estimation of the communication system that provides of embodiment of the present invention.As shown in Figure 1, the simultaneous bias method of estimation of described communication system comprises:

Step S101 carries out R times of over-sampling to the channel estimation results of signal;

Step S102 based on the channel estimation results behind the R times of over-sampling, obtains estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal;

Step S103 according to the relation between the power in the power in the strongest path and time strong path, determines the simultaneous bias of system at least based on the target location of the estimated position in described the strongest path and synchronous point.

The below elaborates with the simultaneous bias method of estimation of specific embodiment to above-mentioned communication system.

In the present embodiment, described communication system is the TD-SCDMA communication system.In other embodiments, described communication system also can adopt for other communication system of spread spectrum, communication systems such as WCDMA, CDMA2000.Therefore, the simultaneous bias method of estimation described in the embodiment of the invention can be applicable to plurality of communication systems, and is not limited only to the TD-SCDMA system.

As described in the background art; simultaneous bias method of estimation of the prior art; under common channel circumstance, good systematic function can be arranged; but under the wireless channel environments such as mobile channel and the living channel that goes out, often can be relatively poor because of the inaccurate systematic function that causes of simultaneous bias estimated result.The below at first is briefly described mobile propagation conditions and the living propagation conditions that goes out.

Mobile propagation conditions is the channel model without decline that two footpaths are arranged.Fig. 2 is the clock skew schematic diagram of communication system under the mobile propagation conditions, as shown in Figure 2, two paths in the mobile propagation conditions, one is static---be assumed to be at t ₀Path P constantly ₀, one is mobile---be assumed to be at t ₀' path P constantly ₀', the amplitude in two paths is identical with phase place, and the time difference between two paths is shown in formula (1).

$\mathrm{\Δ\τ}=B+\frac{A}{2}(1+\sin (\mathrm{\Δ\ω}\·t))---\left(1\right)$

Parameter usually can be according to following table (mobile propagation conditions multipath parameter list) value in the formula (1):

A	5μs
		B	1μs
Δω	40*10 -3s -1

Giving birth to the propagation conditions that goes out is the non-decline communication environments with two signal paths.Give birth to two signal paths of the propagation conditions that goes out, replace between " life " and " going out " state, the appearance position of signal path on time shaft is equiprobable at random.Fig. 3 is the clock skew schematic diagram of giving birth to communication system under the propagation conditions that goes out, and as shown in Figure 3, supposes that two signal paths that occur on certain moment time shaft are respectively at P ₁The path 1 of position and at P ₂The path 2 of position is selected at random from [3 ,-2 ,-1,0,1,2,3] chip in one group of relative time delay (781.25ns), and is had identical amplitude and phase place.Behind the 191ms, at P ₁The path 1 of position disappears (being represented by dotted lines among the figure), and occurs a new delay positions immediately, and the position of appearance is selected from [3 ,-2 ,-1,0,1,2,3] this group of chip at random, but does not comprise the position P at 2 original places, path ₂, such as the position P among Fig. 3 ₁', amplitude, the phase preserving in two paths are constant; After 191ms, be positioned at P ₂The path 2 of position disappears, and occurs a new delay positions immediately, and the position of appearance is selected from [3 ,-2 ,-1,0,1,2,3] this group of chip at random, but does not comprise the position P at 1 original place, path ₁'.Amplitude, the phase place in two paths still remain unchanged; Two so repeatedly appearing and subsidings on time shaft of path of signal.

Mobile propagation conditions and the living propagation conditions that goes out are conventionally known to one of skill in the art, are not described in detail at this.The inventor finds, because the particularity of wireless channel environment under mobile propagation conditions and the living propagation conditions that goes out, may cause the generation of the exit window problem of channel estimation results, only determine that with the strongest path of signal simultaneous bias is difficult to obtain accurately estimated result thereby make in the prior art, and then make systematic function relatively poor.Therefore, the inventor considers, can determine simultaneous bias by the position and the power that estimate two the strongest paths of signal, can effectively avoid making the inaccurate of simultaneous bias estimated result because of the exit window problem of channel estimation results, thereby can well adapt to the wireless channel environments such as mobile channel and the living channel that goes out, obtain preferably systematic function, and do not affect the performance under the conventional channel.

Next the simultaneous bias method of estimation of the communication system in the present embodiment described.

Execution in step S101 at first carries out R times of over-sampling to the channel estimation results of signal.In the present embodiment, described in the step S101 channel estimation results of signal being carried out R times of over-sampling can comprise:

Step S101a carries out R to the channel estimation results of signal ₁Times interpolation;

Step S101b is with described R ₁Channel estimation results after times interpolation is determined the strongest path of signal and the interval that time strong path occurs;

Step S101c, respectively the strongest described path and time strong path occur interval in to described R ₁Channel estimation results after times interpolation carries out R ₂Times interpolation; Wherein, R ₁* R ₂=R.

In specific implementation process, in order to reduce operand, R times of over-sampling interpolation can be carried out in two steps, at first the channel estimation results of signal is carried out the interpolation of less multiple, purpose is to determine first the strongest path of signal and the interval of time strong path appearance, then in the interval of determining, the result after going on foot interpolation through front one is carried out again the interpolation of larger multiple, just can be from through obtaining the estimated position in strong path and estimated position and the power in power and inferior strong path the result after twice interpolation by subsequent step, and carry out accordingly the estimation of simultaneous bias.Owing to only need to carry out for the channel estimation results in certain two interval in the Interpolation Process for the second time, and do not need all channel estimation results in the activation detection window are carried out interpolation, so amount of calculation can greatly reduce raising simultaneous bias Efficiency of estimator.

Need to prove, although R, R ₁, R ₂Between relation only need to satisfy R ₁* R ₂=R gets final product, but as a rule, R, R ₁, R ₂Be positive integer, and 1＜R ₁＜R ₂In the present embodiment, reach 1/16chip in order to make estimated accuracy, get R=16, R ₁=2, R ₂=8.In other embodiments, also can be to R, R ₁, R ₂Get other value, for example: estimated accuracy is in the situation that 1/8chip, R=8, R ₁=2, R ₂=4; Certainly, estimated accuracy is in the situation that 1/16chip, also desirable R=16, R ₁=4, R ₂=4.

When reality is implemented, consideration for cost, more use at present digit compensated crystal oscillator (DCXO) as crystal oscillator in the communication system, yet, because the deviation ratio Temp .-compensation type crystal oscillator (TCXO) of DCXO is large, and can not automatically adjust, in this case, clock skew is larger, and the estimated accuracy of common 1/8chip can not satisfy the requirement of performance, must estimate the clock skew of 1/16chip precision, when the 1/16chip skew appears in clock, the receiving terminal of communication system can estimate clock jitter accurately, thereby adjusts, so that clock jitter is controlled within the 1/16chip all the time.Because estimated accuracy depends on the multiple of over-sampling, therefore, in order to reach the estimated accuracy of 1/16chip, need to be with 16 times of over-samplings.

In the present embodiment, can use first channel estimation results that activates detection window of targeted customer to carry out the synchronism deviation estimation.In other embodiments, also can use other channel estimation results that activate arbitrarily detection window of targeted customer to carry out the synchronism deviation estimation, can also use the channel estimation results of a plurality of activation detection windows of targeted customer to carry out the synchronism deviation estimation.If establishing first channel estimation results that activates detection window is h (k), k=0,1,2 ..., W-1, wherein W is length of window.

Work as R ₁=2, R ₂=8 o'clock, then step S101a was specially: h (k) is carried out 2 times of interpolation, obtain h ' (k).

h′(2k)＝h(k)，k＝0，1，2，...，W-1，

$h^{\′}(2k+1)={\mathrm{\Σ}}_{n=-\frac{M}{2}+1}^{\frac{M}{2}}h(k+n)\·f_2(2n-1),$ k＝0，1，2，...，W-1，

f ₂(x) be raised cosine pulse, $f_2\left(x\right)=\left(\frac{\cos \left(\frac{\mathrm{\π\α}\left(x\right)}{2}\right)}{1-{\mathrm{\α}}^2{\left(x\right)}^2}\right)\·\left(\frac{\sin \left(\frac{\mathrm{\π}\left(x\right)}{2}\right)}{\frac{\mathrm{\π}\left(x\right)}{2}}\right),$

$x=-\frac{2M}{2},...,\frac{2M}{2}.$ Wherein, M is for participating in counting of interpolation, and α is rolloff-factor.In the present embodiment, specifically get M=6, α=0.1.

Need to prove, in the present embodiment, described over-sampling realizes by the raised cosine roll off filter, in other embodiments, also can carry out over-sampling to the channel estimation results of signal by low pass filter.

Work as R ₁=2, R ₂=8 o'clock, step S101b was specially: (k) determine the strongest path of signal and the interval that time strong path occurs with the channel estimation results h ' after described 2 times of interpolation.

L ' _Max=max _0≤i≤2W-2| h ' (i)+h ' (i+1) | ²L ' _MaxIt is the estimated position in strong path of the signal that in through the channel estimation results after 2 times of interpolation, obtains, this estimated position is to the position in the strongest path "ball-park" estimate value comparatively, the left end point in the interval that its strongest signal path can be occurred, the interval that the strongest described path occurs then be [L ' _Max, L ' _Max+ 1].Need to prove, in other embodiments, also can pass through L ' _Max=max _0≤i≤2W-2| h ' (i) | ²Calculate this estimated position in the strongest path of signal.

Among the step S101b with described R ₁Channel estimation results after times interpolation determines that the interval that time strong path occurs of signal comprises: at described R ₁In the channel estimation results after times interpolation, N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty; Wherein N sets based on channel circumstance; Based on the channel estimation results that empties after the described data, determine the interval that time strong path occurs of signal.

Wherein, the purpose that N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty is to make a concerted effort for fear of two or more very not strong signal formations, is the signal on the path time by force thereby cause being mistaken as.Owing to generally having the certain hour interval between the strongest path and time strong path, empty by the data with near N path the strongest path, can search out comparatively exactly time estimated position in strong path.Need to prove, the value of N is set based on the channel circumstance of reality, and the setting range of General N can be 1～3, but the value of N can not be excessive, otherwise may cause the data in inferior strong path are deleted by mistake.

In the present embodiment, get N=2.When specific implementation, can be with sequence { h ' (i) } assignment to sequence { b (i) }, and with sequence { b (i) } at position L ' _MaxAnd two adjacent data zero clearings of the left and right sides, that is:

b(L′ _max-2)＝0；b(L′ _max-1)＝0；b(L′ _max)＝0；b(L′ _max+1)＝0；b(L′ _max+2)＝0；

Then, seek the interval of time strong path appearance of signal in the sequence after the described data of zero clearing { b (i) }:

V′ _max＝max _0≤i≤2W-2|b(i)+b(i+1)| ²。

Similarly, V ' _MaxBe through 2 times of interpolation and empty the strongest path and near the estimated position in time strong path of the signal that obtains in the logical estimated result of letter behind the corresponding data in path, this estimated position is to the position in inferior strong path "ball-park" estimate value comparatively, the interval that the left end point in the interval that its signal time strong path can be occurred, described strong path occur then be [V ' _Max, V ' _Max+ 1].

Work as R ₁=2, R ₂=8 o'clock, step S101c was specially: the interval that occurs in the strongest described path [L ' _Max, L ' _Max+ 1] in the channel estimation results h ' after described 2 times of interpolation (k) is carried out 8 times of interpolation, and the interval that occurs in inferior strong path [V ' _Max, V ' _Max+ 1] in the channel estimation results h ' after described 2 times of interpolation (k) is carried out 8 times of interpolation.

Wherein, interval [L ' _Max, L ' _Max+ 1] in to h ' (k) carry out 8 times of interpolation after, obtain h " (k).

If (L ' _Max) mod (2)=0, then:

$h^{\′\′}\left(j\right)={\mathrm{\Σ}}_{m=-\frac{M}{2}+1}^{\frac{M}{2}}h(\frac{{L^{\′}}_{\max }}{2}+m)\·f_{16}(16m-j),$ j＝1，2，3，...，7；

If (L ' _Max) mod (2)=1, then:

$h^{\′\′}\left(j\right)={\mathrm{\Σ}}_{m=-\frac{M}{2}+1}^{\frac{M}{2}}h(\frac{{L^{\′}}_{\max }-1}{2}+m)\·f_{16}(16m-8-j),$ j＝1，2，3，...，7；

$f_{16}\left(x\right)=\left(\frac{\cos \left(\frac{\mathrm{\π\α}\left(x\right)}{16}\right)}{1-\frac{{\mathrm{\α}}^2{\left(x\right)}^2}{64}}\right)\·\left(\frac{\sin \left(\frac{\mathrm{\π}\left(x\right)}{16}\right)}{\frac{\mathrm{\π}\left(x\right)}{16}}\right),$ $x=-\frac{16M}{2},...,\frac{16M}{2}.$

Similarly, interval [V ' _Max, V ' _Max+ 1] in to h ' (k) carry out 8 times of interpolation after, obtain u " (k).

If (V ' _Max) mod (2)=0, then:

$u^{\′\′}\left(j\right)={\mathrm{\Σ}}_{m=-\frac{M}{2}+1}^{\frac{M}{2}}h(\frac{{V^{\′}}_{\max }}{2}+m)\·f_{16}(16m-j),$ j＝1，2，3，...，7；

If (V ' _Max) mod (2)=1, then:

$u^{\′\′}\left(j\right)={\mathrm{\Σ}}_{m=-\frac{M}{2}+1}^{\frac{M}{2}}h(\frac{{V^{\′}}_{\max }-1}{2}+m)\·f_{16}(16m-8-j),$ j＝1，2，3，...，7；

$f_{16}\left(x\right)=\left(\frac{\cos \left(\frac{\mathrm{\π\α}\left(x\right)}{16}\right)}{1-\frac{{\mathrm{\α}}^2{\left(x\right)}^2}{64}}\right)\·\left(\frac{\sin \left(\frac{\mathrm{\π}\left(x\right)}{16}\right)}{\frac{\mathrm{\π}\left(x\right)}{16}}\right),$ $x=-\frac{16M}{2},...,\frac{16M}{2}.$

Need to prove, among the step S101c, based on (L ' _Max) result of mod (2) take respectively different calculating formulas to h " (j) calculate, based on (V ' _Max) result of mod (2) takes respectively different calculating formulas to u and " (j) calculate, and " (j) calculate the second estimated value L of the estimated position in strong path " with h in subsequent step S102 _Max, " (j) calculate time the second estimated value V of the estimated position in strong path " with u _Max, so can reduce amount of calculation, raise the efficiency.In other embodiments, can not calculate L by this kind mode " yet _MaxAnd V " _Max, but can calculate as follows:

Step S1, carry out down-sampling to channel estimation results h (k):

h ₁₆" (16k)=and h (k), k=0,1,2 ..., W-1, wherein W is length of window;

h ₁₆″(16k+j)＝0 ，j＝1，2，3，...，15 ，k＝0，1，2，...，W-1。

Step S2, carry out 16 times of filtering to the result behind the down-sampling:

H " _Conv(k)=conv (h ₁₆", f ₁₆), k=0,1,2 ..., 16W+16M; Wherein, h ₁₆" expression h ₁₆" sequence (k), f ₁₆Expression f ₁₆(x) sequence, conv is the convolution algorithm function, M is for participating in counting of interpolation.

Need to prove, in the embodiment of the invention, based on (L ' _Max) result of mod (2) calculate h " (j) and based on (V ' _Max) result of mod (2) calculates u " process (j) namely is to h " _Conv(k)=conv (h ₁₆", f ₁₆) simplification.

Step S3, because the above-mentioned convolution algorithm of process can obtain the numerical value more than 16W, therefore, filtered value must begin value after the 8M number, obtains 16 times of filtered values:

h″(k)＝h″ _conv(k+8M)，k＝0，1，2，...，16W-1；

Step S4 is from h " (k) at L ' _MaxFind out peaked position L near * 8 positions " _Max, from h " (k) at V ' _MaxFind out the position V of second largest value near * 8 positions " _MaxPerhaps also can directly " find out peaked position L (k) " from h _MaxAnd the position V of second largest value " _Max

After the channel estimation results of signal carried out R times of over-sampling, execution in step S102 based on the channel estimation results behind the R times of over-sampling, obtained estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal.

In the present embodiment, step S102 can comprise:

Step S102a, from described to R ₁Obtain described the first estimated value L ' of the estimated position in strong path in the channel estimation results after times interpolation _MaxWith described inferior by force the first estimated value V ' of the estimated position in path _Max

Step S102b, from described to R ₁Channel estimation results after times interpolation carries out R ₂Obtain described the second estimated value L of the estimated position in strong path among the result after times interpolation " _MaxWith power and described inferior by force the second estimated value V of the estimated position in path " _MaxAnd power;

Step S102c is with R ₂* L ' _MaxWith L " _MaxSum is as the described estimated position in strong path, with R ₂* V ' _MaxWith V " _MaxSum is as the estimated position in described strong path.

Wherein, the first estimated value L ' of the estimated position in strong path among the step S102a _Max, inferior strong path the first estimated value V ' of estimated position _Max, can execution in step S101b estimate that the strongest described path, inferior strong path occur interval the time can obtain.

Work as R ₁=2, R ₂=8 o'clock, the concrete implementation of step S102b was as follows:

" obtain described the second estimated value L of the estimated position in strong path (k) " from the described as a result h that channel estimation results h ' after 2 times of interpolation (k) is carried out after 8 times of interpolation _MaxAnd power.

Note P " (j)=| h " (j) | ², j=1,2,3 ..., 7; P " (0)=| h ' (L ' _Max) | ², P " and (8)=| h ' (L ' _Max+ 1) | ², then in the interval [L ' _Max, L ' _Max+ 1] in h ' (k) is carried out 8 times of channel estimation results h after the interpolation " estimated position in the strongest path that obtains (k) is:

${L^{\′\′}}_{\max }=\underset{j\∈\left\{\mathrm{0,1,2,3,4,5,6,7,8}\right\}}{\arg \max }\left\{P^{\′\′}\left(j\right)\right\},$ Wherein, argmax represents to ask the value of the parameter of one group of sequence, and the value in using these parameters time-sequence row reaches maximum, then L " _Max" the value of corresponding j when (j) reaching maximum that is to make function P.Because L " _MaxThat h ' (k) is carried out 8 times of channel estimation results h after the interpolation " estimated position in the strongest path that obtains (k), this estimated position are the comparatively accurate estimated values in position to the strongest path of signal, in the present embodiment with L " _MaxBe called the second estimated value of the estimated position in strong path.

The power in strong path is P " _Max=P " (L " _Max), P " _MaxNamely be the described power corresponding to estimated position in strong path.

Similarly, " obtain the second estimated value V of the estimated position in described strong path (k) " from the described as a result u that channel estimation results h ' after 2 times of interpolation (k) is carried out after 8 times of interpolation _MaxAnd power.

Note Q " (j)=| u " (j) | ², j=1,2,3 ..., 7; Q " (0)=| u ' (V ' _Max) | ², Q " and (8)=| u ' (V ' _Max+ 1) | ², then in the interval [V ' _Max, V ' _Max+ 1] in h ' (k) is carried out 8 times of channel estimation results u after the interpolation " estimated position in time strong path that obtains (k) is:

${V^{\′\′}}_{\max }=\underset{j\∈\left\{\mathrm{0,1,2,3,4,5,6,7,8}\right\}}{\arg \max }\left\{Q^{\′\′}\left(j\right)\right\},$ V " _Max" the value of corresponding j when (j) reaching maximum that is to make function Q.Because V " _MaxThat h ' (k) is carried out 8 times of channel estimation results u after the interpolation " estimated position in time strong path that obtains (k), this estimated position are to the comparatively accurate estimated value in the position in time strong path of signal, in the present embodiment with V " _MaxBe called time the second estimated value of the estimated position in strong path.

The power in inferior strong path is Q " _Max=Q " (V " _Max), Q " _MaxNamely be the power corresponding to estimated position in described strong path.

In the present embodiment, because the first estimated value L ' of the estimated position in the strongest path of signal _MaxIn to the result after 2 times of interpolation of channel estimation results, to obtain, and the second estimated value L of the estimated position in strong path " _MaxThen be in to the result after 16 times of interpolation of channel estimation results, to obtain L ' _MaxPositional representation to the strongest path is comparatively rough, L " _MaxPositional representation to the strongest path is more accurate.In like manner, because the first estimated value V ' of the estimated position in time strong path of signal _MaxIn to the result after 2 times of interpolation of channel estimation results, to obtain, and the second estimated value V of the estimated position in inferior strong path " _MaxThen be in to the result after 16 times of interpolation of channel estimation results, to obtain V ' _MaxPositional representation to inferior strong path is comparatively rough, V " _MaxPositional representation to inferior strong path is more accurate.Under the 1/16chip precision, calculate the described estimated position L in strong path _PeakAnd the estimated position V in inferior strong path _Peak, i.e. concrete execution in step S102c:

L _peak＝8L′ _max+L″ _max，L _peak∈{0，1，2，...，16W-1}；

V _peak＝8V′ _max+V″ _max，V _peak∈{0，1，2，...，16W-1}。

In the TD-SCDMA communication system, for the channel estimation results of a subframe or a plurality of subframes, all can adopt said process to obtain the estimated position in the strongest path of a signal and the estimated position in time strong path, and corresponding power.In subsequent step, can based on the relation between the power in the power in the strongest path and time strong path, utilize the target location of above-mentioned these two estimated positions and synchronous point to calculate position corresponding to synchronous point.The target location of described synchronous point be communication system for the desired location of synchronous point, this position can get through calculating in advance by the path of initial determined peak signal.

Behind the estimated position and power in time strong path of the estimated position in the strongest path that gets access to signal and power and signal, execution in step S103, according to the relation between the power in the power in the strongest path and time strong path, determine at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.

In the present embodiment, step S103 comprises: judge that whether the power in described strong path is greater than threshold value, be then with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point, otherwise with the difference of the target location of the estimated position in described the strongest path and the described synchronous point simultaneous bias as system; Described threshold value is the described power in strong path and the product of threshold parameter.

Because described threshold value is the power in described the strongest path and the product of threshold parameter, then judge the power in described strong path and the relation between the threshold value, be the relation between the power in the power of judging described strong path and described the strongest path, comparatively approach the power in strong path if judge the power in time strong path of signal, half of power that for example surpasses the strongest path, then showing may be inaccurate because of the result that the channel estimation results exit window causes simultaneous bias to be estimated, carry out simultaneous bias estimation in conjunction with the estimated position in strong path with time estimated position in strong path with regard to needing in the present embodiment so, specifically can be with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point, otherwise show not exit window of channel estimation results, can be only carrying out simultaneous bias by the estimated position in strong path and estimate, specifically can be the simultaneous bias with the difference computing system of the target location of the estimated position in described the strongest path and described synchronous point.

Wherein, described with described the strongest path the estimated position and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point comprise: with the estimated position in described the strongest path with described time by force the centre position between the estimated position in path determine the integral multiple chip offset; Calculate decimal times chip offset with the described estimated position in strong path and the target location of described synchronous point; With described integral multiple chip offset and the decimal times chip offset sum simultaneous bias as system.

During implementation, the estimated position of establishing the strongest current path and time strong path is respectively L _Peak, V _Peak, the target location of synchronous point is L _Trgt, then can calculate in accordance with the following steps for the estimation of simultaneous bias:

At first judge the power Q in time strong path of the R times of signal after the interpolation " _MaxWhether greater than certain threshold T hrd, wherein Thrd=ε P " _Max, P " _MaxThe power in the strongest path of the signal that calculate to obtain before namely being; ε is a threshold parameter, its span be [1/2,1).In the present embodiment, get ε=1/2, then the value of Thrd is P " _MaxHalf.

If Q " _Max≤ Thrd then only needs to use the estimated position L in strong path _PeakTarget location L with synchronous point _TrgtCalculate synchronism deviation Δ L, computational process is as follows:

ΔL＝L _peak-L _trgt；

If Q " _Max＞Thrd then needs to use simultaneously the estimated position L in strong path _PeakAnd with the estimated position V in inferior strong path _PeakBetween centre position T ₀, synchronous point target location L _TrgtCalculate synchronism deviation Δ L, computational process is as follows:

1) calculates the estimated position L in strong path _PeakEstimated position V with inferior strong path _PeakBetween centre position T ₀:

T ₀=round ((L _Peak+ V _Peak)/2), round is the round function;

2) to middle position T ₀Integer chip approximate (with T ₀Value be transformed into the integer chip level):

$T_{0,\mathrm{int}}=\mathrm{round}\left(\frac{T_0}{R}\right)*R;$

In the specific embodiment, when R=16, that is: $T_{0,\mathrm{int}}=\mathrm{round}\left(\frac{T_0}{16}\right)*16;$

3) for integral multiple chip shifted by delta L _IntCalculating:

ΔL _int＝T _0，int-L _trgt；

4) decimal times chip shifted by delta L _FracThe estimated position L in strong path according to signal _PeakCalculate:

Δ L _Frac=mod (L _Peak-L _Trgt, R), wherein mod is MOD function;

In the specific embodiment, when R=16, that is: Δ L _Frac=mod (L _Peak-L _Trgt, 16);

5) total deviation is calculated:

ΔL＝ΔL _int+ΔL _frac

Synchronism deviation is Δ L, if take 1/16chip as unit, when carrying out the synchronous point adjustment, be that unit adjusts according to 1/8chip then, like this will so that the synchronism deviation of system between-1/16chip 1/16chip, fluctuate, in general, the clock jitter of the existence-1/16chip of system is very little on the systematic function impact.

To sum up, in the present embodiment, determine the synchronous point position by estimating two the strongest paths of signal, can effectively avoid making the inaccurate of simultaneous bias estimated result because of the exit window problem of channel estimation results, give birth to the wireless channel environments such as channel and mobile channel that go out thereby can well adapt to, obtain preferably systematic function, and do not affect the performance under the conventional channel.

The simultaneous bias method of estimation of corresponding above-mentioned communication system, the present embodiment also provides a kind of simultaneous bias estimation unit of communication system.Fig. 4 is the structural representation of the simultaneous bias estimation unit of the communication system that provides of the embodiment of the invention, as shown in Figure 4, the simultaneous bias estimation unit of described communication system comprises: over-sampling unit 10 is suitable for the channel estimation results of signal is carried out R times of over-sampling; Acquiring unit 20 links to each other with described over-sampling unit 10, is suitable for based on the channel estimation results behind the R times of over-sampling, obtains estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal; Simultaneous bias determining unit 30 links to each other with described acquiring unit 20, is suitable for according to the relation between the power in the power in the strongest path and path time by force, determines at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.In the present embodiment, described communication system is the TD-SCDMA communication system.

During implementation, described over-sampling unit 10 comprises: the first interpolating unit 101 is suitable for the channel estimation results of signal is carried out R ₁Times interpolation; Interval determining unit 102 links to each other with described the first interpolating unit 101, is suitable for described R ₁Channel estimation results after times interpolation is determined the strongest path of signal and the interval that time strong path occurs; The second interpolating unit 103 links to each other with described the first interpolating unit 101, interval determining unit 102, be suitable for respectively the strongest described path and time strong path occur interval in to described R ₁Channel estimation results after times interpolation carries out R ₂Times interpolation; Wherein, R ₁* R ₂=R.In the present embodiment, get R=16, R ₁=2, R ₂=8.During actual enforcement, described over-sampling unit 10 comprises raised cosine roll off filter or low pass filter.

Described acquiring unit 20 comprises: the first acquiring unit 201 is suitable for from described R ₁Obtain described the first estimated value L ' of the estimated position in strong path in the channel estimation results after times interpolation _MaxWith described inferior by force the first estimated value V ' of the estimated position in path _Max Second acquisition unit 202 is suitable for from described R ₁Channel estimation results after times interpolation carries out R ₂Obtain described the second estimated value L of the estimated position in strong path among the result after times interpolation " _MaxWith power and described inferior by force the second estimated value V of the estimated position in path " _MaxAnd power; The 3rd acquiring unit 203 links to each other with described the first acquiring unit 201, second acquisition unit 202, is suitable for R ₂* L ' _MaxWith L " _MaxSum is as the described estimated position in strong path, with R ₂* V ' _MaxWith V " _MaxSum is as the estimated position in described strong path.

Described interval determining unit 102 can comprise: the pretreatment unit (not shown), and at described R ₁In the channel estimation results after times interpolation, N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty; Wherein N sets based on channel circumstance; The first interval determining unit (not shown) links to each other with described pretreatment unit, is suitable for based on the channel estimation results that empties after the described data, determines the interval that time strong path occurs of signal.

Described simultaneous bias determining unit 30 comprises: judging unit 301 is suitable for judging that whether the power in described strong path is greater than threshold value; Described threshold value is the described power in strong path and the product of threshold parameter; The first simultaneous bias determining unit 302, link to each other with described judging unit 301, when being suitable for power in described time strong path greater than threshold value, with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point; The second simultaneous bias determining unit 303 links to each other with described judging unit 301, when being suitable for power in described time strong path and being less than or equal to threshold value, with the difference of the target location of the estimated position in described the strongest path and the described synchronous point simultaneous bias as system.During actual enforcement, the span of described threshold parameter can for [1/2,1).

Described the first simultaneous bias determining unit 302 comprises: integral multiple skew determining unit (not shown) is suitable for the estimated position L with described the strongest path _PeakEstimated position V with described strong path _PeakBetween centre position T ₀Determine integral multiple chip offset Δ L _IntDecimal doubly is offset the determining unit (not shown), is suitable for the described estimated position L in strong path _PeakTarget location L with described synchronous point _TrgtCalculate decimal times chip offset Δ L _FracTotal drift determining unit (not shown) is suitable for described integral multiple chip offset Δ L _IntWith decimal times chip offset Δ L _FracSum is as the simultaneous bias of system.When specific implementation process, described integral multiple chip offset Δ L _Int=T _{0, int}-L _Trgt, wherein: T ₀=round ((L _Peak+ V _Peak)/2), round is the round function; Described decimal times chip offset Δ L _Frac=mod (L _Peak-L _Trgt, R), wherein mod is MOD function.

In addition, the present embodiment also provides a kind of portable terminal that comprises the simultaneous bias estimation unit of above-mentioned communication system.During implementation, described portable terminal can also comprise the first adjustment unit, links to each other with described simultaneous bias estimation unit, is suitable for adjusting synchronous point based on the determined simultaneous bias result of the simultaneous bias estimation unit of described communication system.

The present embodiment also provides a kind of base station that comprises the simultaneous bias estimation unit of above-mentioned communication system.During implementation, described base station can also comprise the second adjustment unit, links to each other with described simultaneous bias estimation unit, is suitable for adjusting synchronous point based on the determined simultaneous bias result of the simultaneous bias estimation unit of described communication system.

The simultaneous bias estimation unit of described communication system, comprise the portable terminal of described simultaneous bias estimation unit and comprise that the implementation of the base station of described simultaneous bias estimation unit can with reference to the enforcement of the simultaneous bias method of estimation of the described communication system of the present embodiment, not repeat them here.

To sum up, the simultaneous bias method of estimation of the communication system that embodiment of the present invention provides and device, portable terminal and base station have following beneficial effect at least:

Channel estimation results to signal carries out over-sampling, obtain estimated position and the power in the strongest path and the inferior strong path of signal the result behind over-sampling, again according to the relation between the power in the power in described the strongest path and described strong path, at least determine the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point, so, determine that by estimating two the strongest paths of signal the synchronous point position can estimate the simultaneous bias of system exactly, thereby can well adapt to the wireless channel environments such as mobile channel and the living channel that goes out, obtain preferably systematic function, and do not affect the performance under the conventional channel.

The process that to carry out to the channel estimation results of signal R times of over-sampling is divided into two steps, carries out first R ₁Times interpolation is with R ₁Channel estimation results after times interpolation is determined respectively the strongest path of signal and the interval that time strong path occurs, more respectively to carrying out R in the strongest path and the interval that time strong path occurs ₂Times interpolation to be to estimate position and the power in the strongest path and time strong path, wherein, and R ₁* R ₂=R owing to not needing all channel estimation results in the activation detection window are carried out interpolation, has therefore greatly reduced amount of calculation, has improved the simultaneous bias Efficiency of estimator.

For the communication system that adopts DCXO as clock, estimated accuracy is brought up to 1/16chip, so that when the 1/16chip skew appears in system, just can effectively estimate clock jitter, thereby adjust, and need to when the 1/8chip skew occurring, can not adjust, further improved systematic function.

Although adopt TCXO can realize the estimated accuracy of 1/16chip as the crystal oscillator of communication system, it has higher cost, and can replace TCXO with DCXO in the technical program, can access identical performance, effectively provides cost savings.

Although the present invention with preferred embodiment openly as above; but it is not to limit the present invention; any those skilled in the art without departing from the spirit and scope of the present invention; can utilize method and the technology contents of above-mentioned announcement that technical solution of the present invention is made possible change and modification; therefore; every content that does not break away from technical solution of the present invention; to any simple modification, equivalent variations and modification that above embodiment does, all belong to the protection range of technical solution of the present invention according to technical spirit of the present invention.

Claims (26)

1. the simultaneous bias method of estimation of a communication system is characterized in that, comprising:

Channel estimation results to signal carries out R times of over-sampling;

Based on the channel estimation results behind the R times of over-sampling, obtain estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal;

According to the relation between the power in the power in the strongest path and time strong path, determine at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.

2. the simultaneous bias method of estimation of communication system according to claim 1 is characterized in that, described channel estimation results to signal carries out R times of over-sampling and comprises:

Channel estimation results to signal carries out R ₁Times interpolation;

With described R ₁Channel estimation results after times interpolation is determined the strongest path of signal and the interval that time strong path occurs;

Respectively the strongest described path and time strong path occur interval in to described R ₁Channel estimation results after times interpolation carries out R ₂Times interpolation; Wherein, R ₁* R ₂=R.

3. the simultaneous bias method of estimation of communication system according to claim 2, it is characterized in that, described based on the channel estimation results behind the R times of over-sampling, the estimated position and the power that obtain time strong path of the estimated position in the strongest path of signal and power and signal comprise:

From described to R ₁Obtain described the first estimated value L ' of the estimated position in strong path in the channel estimation results after times interpolation _MaxWith described inferior by force the first estimated value V ' of the estimated position in path _Max

From described to R ₁Channel estimation results after times interpolation carries out R ₂Obtain described the second estimated value L of the estimated position in strong path among the result after times interpolation " _MaxWith power and described inferior by force the second estimated value V of the estimated position in path " _MaxAnd power;

With R ₂* L ' _MaxWith L " _MaxSum is as the described estimated position in strong path, with R ₂* V ' _MaxWith V " _MaxSum is as the estimated position in described strong path.

4. the simultaneous bias method of estimation of communication system according to claim 2 is characterized in that, and is described with described R ₁Channel estimation results after times interpolation determines that the interval that time strong path occurs of signal comprises:

At described R ₁In the channel estimation results after times interpolation, N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty; Wherein N sets based on channel circumstance;

Based on the channel estimation results that empties after the described data, determine the interval that time strong path occurs of signal.

5. the simultaneous bias method of estimation of communication system according to claim 2 is characterized in that, R=16, R ₁=2, R ₂=8.

6. the simultaneous bias method of estimation of communication system according to claim 1, it is characterized in that, according to the relation between the power in the power in the strongest path and time strong path, determine that based on the estimated position in described the strongest path and the target location of synchronous point the simultaneous bias of system comprises at least:

Judge that whether the power in described strong path is greater than threshold value, be then with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point, otherwise with the difference of the target location of the estimated position in described the strongest path and the described synchronous point simultaneous bias as system; Described threshold value is the described power in strong path and the product of threshold parameter.

7. the simultaneous bias method of estimation of communication system according to claim 6 is characterized in that, the span of described threshold parameter be [1/2,1).

8. the simultaneous bias method of estimation of communication system according to claim 6, it is characterized in that, described with described the strongest path the estimated position and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point comprise:

With the described estimated position L in strong path _PeakEstimated position V with described strong path _PeakBetween centre position T ₀Determine integral multiple chip offset Δ L _Int

With the described estimated position L in strong path _PeakTarget location L with described synchronous point _TrgtCalculate decimal times chip offset Δ L _Frac

With described integral multiple chip offset Δ L _IntWith decimal times chip offset Δ L _FracSum is as the simultaneous bias of system.

9. the simultaneous bias method of estimation of communication system according to claim 8 is characterized in that,

Described integral multiple chip offset Δ L _Int=T _{0, int}-L _Trgt, wherein:

T ₀=round ((L _Peak+ V _Peak)/2), round is the round function;

Described decimal times chip offset Δ L _Frac=mod (L _Peak-L _Trgt, R), wherein mod is MOD function.

10. the simultaneous bias method of estimation of communication system according to claim 1 is characterized in that, described over-sampling is realized by raised cosine roll off filter or low pass filter.

11. the simultaneous bias method of estimation of communication system according to claim 1 is characterized in that, described communication system is the TD-SCDMA communication system.

12. the simultaneous bias estimation unit of a communication system is characterized in that, comprising:

The over-sampling unit is suitable for the channel estimation results of signal is carried out R times of over-sampling;

Acquiring unit is suitable for based on the channel estimation results behind the R times of over-sampling, obtains estimated position and the power in time strong path of the estimated position in the strongest path of signal and power and signal;

The simultaneous bias determining unit is suitable for according to the relation between the power in the power in the strongest path and path time by force, determines at least the simultaneous bias of system based on the target location of the estimated position in described the strongest path and synchronous point.

13. the simultaneous bias estimation unit of communication system according to claim 12 is characterized in that, described over-sampling unit comprises:

The first interpolating unit is suitable for the channel estimation results of signal is carried out R ₁Times interpolation;

Interval determining unit is suitable for described R ₁Channel estimation results after times interpolation is determined the strongest path of signal and the interval that time strong path occurs;

The second interpolating unit, be suitable for respectively the strongest described path and time strong path occur interval in to described R ₁Channel estimation results after times interpolation carries out R ₂Times interpolation; Wherein, R ₁* R ₂=R.

14. the simultaneous bias estimation unit of communication system according to claim 13 is characterized in that, described acquiring unit comprises:

The first acquiring unit is suitable for from described R ₁Obtain described the first estimated value L ' of the estimated position in strong path in the channel estimation results after times interpolation _MaxWith described inferior by force the first estimated value V ' of the estimated position in path _Max

Second acquisition unit is suitable for from described R ₁Channel estimation results after times interpolation carries out R ₂Obtain described the second estimated value L of the estimated position in strong path among the result after times interpolation " _MaxWith power and described inferior by force the second estimated value V of the estimated position in path " _MaxAnd power;

The 3rd acquiring unit is suitable for R ₂* L ' _MaxWith L " _MaxSum is as the described estimated position in strong path, with R ₂* V ' _MaxWith V " _MaxSum is as the estimated position in described strong path.

15. the simultaneous bias estimation unit of communication system according to claim 13 is characterized in that, described interval determining unit comprises:

Pretreatment unit is suitable at described R ₁In the channel estimation results after times interpolation, N the adjacent data corresponding to position of left end point position and the left and right sides thereof in the interval that the strongest described path is occurred empty; Wherein N sets based on channel circumstance;

The first interval determining unit is suitable for based on the channel estimation results that empties after the described data, determines the interval that time strong path occurs of signal.

16. the simultaneous bias estimation unit of communication system according to claim 13 is characterized in that, R=16, R ₁=2, R ₂=8.

17. the simultaneous bias estimation unit of communication system according to claim 12 is characterized in that, described simultaneous bias determining unit comprises:

Judging unit is suitable for judging that whether the power in described strong path is greater than threshold value; Described threshold value is the described power in strong path and the product of threshold parameter;

The first simultaneous bias determining unit, when being suitable for power in described time strong path greater than threshold value, with the estimated position in described the strongest path and and the estimated position in described strong path between the centre position and the simultaneous bias of the target location computing system of synchronous point;

The second simultaneous bias determining unit is when being suitable for power in described time strong path and being less than or equal to threshold value, with the difference of the target location of the estimated position in described the strongest path and the described synchronous point simultaneous bias as system.

18. the simultaneous bias estimation unit of communication system according to claim 17 is characterized in that, the span of described threshold parameter be [1/2,1).

19. the simultaneous bias estimation unit of communication system according to claim 17 is characterized in that, described the first simultaneous bias determining unit comprises:

Integral multiple skew determining unit is suitable for the estimated position L with described the strongest path _PeakEstimated position V with described strong path _PeakBetween centre position T ₀Determine integral multiple chip offset Δ L _Int

Decimal doubly is offset determining unit, is suitable for the described estimated position L in strong path _PeakTarget location L with described synchronous point _TrgtCalculate decimal times chip offset Δ L _Frac

The total drift determining unit is suitable for described integral multiple chip offset Δ L _IntWith decimal times chip offset Δ L _FracSum is as the simultaneous bias of system.

20. the simultaneous bias estimation unit of communication system according to claim 19 is characterized in that,

Described integral multiple chip offset Δ L _Int=T _{0, int}-L _Trgt, wherein:

T ₀=round ((L _Peak+ V _Peak)/2), round is the round function;

Described decimal times chip offset Δ L _Frac=mod (L _Peak-L _Trgt, R), wherein mod is MOD function.

21. the simultaneous bias estimation unit of communication system according to claim 12 is characterized in that, described over-sampling unit comprises raised cosine roll off filter or low pass filter.

22. the simultaneous bias estimation unit of communication system according to claim 12 is characterized in that, described communication system is the TD-SCDMA communication system.

23. a portable terminal is characterized in that, comprises the simultaneous bias estimation unit of each described communication system of claim 12 to 22.

24. portable terminal according to claim 23 is characterized in that, also comprises the first adjustment unit, is suitable for adjusting synchronous point based on the determined simultaneous bias result of the simultaneous bias estimation unit of described communication system.

25. a base station is characterized in that, comprises the simultaneous bias estimation unit of each described communication system of claim 12 to 22.

26. base station according to claim 25 is characterized in that, also comprises the second adjustment unit, is suitable for adjusting synchronous point based on the determined simultaneous bias result of the simultaneous bias estimation unit of described communication system.

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