CN101577559B - Method and device for compensating phase of receiver - Google Patents

Abstract

The invention discloses a method and a device for compensating the phase of a receiver; the phase compensation method comprises the following steps of: receiving a signal data to carry out the channelimpulse response and obtaining the impulse response data subsequently; judging the position of a useful path in the impulse response data; obtaining the coordinates of the useful path positions, wher ein the useful path is a code chip which leads the power sum of the front channel impulse response and the back channel impulse response in the impulse response data to achieve a prearranged range; utilizing the coordinates of the useful path positions to calculate the average phase deviation of the signal data; and carrying out the phase compensation to the signal data by the average phase deviation. The phase compensation method and the device can extract the path with higher reliability in the phase estimation to be used for phase estimation and compensation, thus improving the receiving performance correspondingly.

Description

The phase compensating method of receiver and device

Technical field

The present invention relates to wireless communication technique field, refer in particular to a kind of phase compensating method and device of receiver.

Background technology

Along with the Future Multimedia business demand growing to high speed data transfer, wireless data service will sharply increase, this just requires 3G (Third Generation) Moblie (3G) system should have the Some features of applicable transmitting data service, as high data volume, high sudden, high reliability etc.

For the time division duplex in 3G (Third Generation) Moblie (TDD) system, TD SDMA (TD-SCDMA) system for example, support that mobile phone TV services are important features, therefore need to provide high-quality high speed data transfer business for broadcast message.Along with development and the 3G (Third Generation) Moblie rise in the world of wireless communication technology, Radio Resource, as a kind of limited resource, becomes more and more nervous.For the TD-SCDMA system of one of 3G mainstream standard, its Radio Resource being assigned with is also very limited.Therefore, also proposed recently a kind of special carrier TD-MBMS (time-division multimedia broadcast multicast service) scheme, special carrier refers in particular to the shared special-purpose frequency range of TD-MBMS, and to take frequency range different from TD-SCDMA.

Generally, the phase compensating method of receiver is to adopt whole channel impulse response to do phase estimation, but in the fading channel of multipath, in the situation that particularly expansion of the time delay of special carrier MBMS channel is larger, not all path is all very accurate, adopt like this phase estimation that whole channel impulse response is done conventionally not accurate enough, therefore will inevitably reduce the performance of receiver.

Therefore, how to provide a kind of precise phase compensation method based on balancing technique just to become technical problem urgently to be resolved hurrily.

Summary of the invention

The object of technical solution of the present invention is to provide a kind of phase compensating method and device of receiver, can extract the higher path of confidence level in phase estimation and be used for carrying out phase estimation and compensation, with corresponding raising receptivity.

For achieving the above object, one aspect of the present invention provides a kind of phase compensating method of receiver, described phase compensating method comprises: receive a signal data and carry out the impulse response data that obtain after channel impulse response, judge the position in useful footpath in described impulse response data, obtain useful path positions coordinate, described useful footpath is the chip that makes the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach a preset range; Utilize described useful path positions coordinate, calculate the average phase deviation of described signal data; According to described average phase deviation, described signal data is carried out to phase compensation.

Preferably, phase compensating method described above, the position in useful footpath in the described impulse response data of described judgement, the step that obtains described useful path positions coordinate specifically comprises: the position that judges main footpath in described impulse response data, obtain main path position coordinate, described main footpath is to make the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach maximum chip; Described preset range, with respect to time gate limit value and/or the power threshold of corresponding relation between described main footpath, is determined according to described time gate limit value and/or power threshold in default described useful footpath; According to described main path position coordinate, described time gate limit value and/or described power threshold, calculate and obtain described useful path positions coordinate.

Preferably, phase compensating method described above, described phase compensating method is applied to multimedia broadcasting Single Frequency Network system TD-MBSFN, described impulse response data comprise front channel impulse response sequence, data symbol sequence and rear channel impulse response sequence, and the number of chips of described front channel impulse response sequence and described rear channel impulse response sequence is 64.

Preferably, phase compensating method described above, when described signal data is n time slot, the position in main footpath described in the described impulse response data of described judgement, the computing formula that obtains described main path position coordinate is:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\∈(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$

Index wherein _maxfor described main path position coordinate, i is the chip position of described front channel impulse response sequence and described rear channel impulse response sequence; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position, $G_i\left(\underset{i\∈(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$ Refer to when (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

Preferably, phase compensating method described above, according to described main path position coordinate, described time gate limit value and/or described power threshold, the computing formula of calculating the described useful path positions coordinate of acquisition is:

index _max-ξ≤j≤index _max+ξ

And/or, (| h _n(j) | ²+ | h _n+1(j) | ²)>=(| h _n(index _max) | ²+ | h _n+1(index _max) | ²) σ, j=1,2...64

Wherein, j is described useful path positions coordinate, and ξ is described time gate limit value, and σ is described power threshold; h _n(j) be the front channel impulse response at described useful path positions coordinate place, h _n+1(j) be the rear channel impulse response at described useful path positions coordinate place; h _n(index _max) be the front channel impulse response at described main path position coordinate place, h _n+1(index _max) be the rear channel impulse response at described main path position coordinate place.

Preferably, phase compensating method described above, when described signal data is normal time slot, describedly utilizes described useful path positions coordinate, and the computing formula of calculating the average phase deviation of described signal data is:

θ _i＝arg(h _n+1(j)/h _n(j))/864，j＝0，1，..，N-1

And $\widehat{\mathrm{\θ}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\Σ}}}{\mathrm{\θ}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response at j place, h _n(j) for described useful path positions coordinate is the front channel impulse response at j place,

described average phase deviation for described data.

Preferably, phase compensating method described above, when described signal data is normal time slot, after the compensation of described signal data being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\×\exp (-j\widehat{\mathrm{\θ}}\×(496-k)),k=1,...,960$

E wherein _nbe to receive data described in n time slot,

for data after described compensation,

Preferably, phase compensating method described above, when described signal data is special time slot, describedly utilizes described useful path positions coordinate, and the computing formula of calculating the average phase deviation of described signal data is:

θ _j＝arg(h _n+1(j)/h _n(j))/352，j＝0，1，..，N-1

And $\widehat{\mathrm{\θ}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\Σ}}}{\mathrm{\θ}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response of j position, h _n(j) for described useful path positions coordinate is the front channel impulse response of j position,

described average phase deviation for described signal data.

Preferably, phase compensating method described above, described signal data is during for gap in short-term, and after the compensation of described signal data being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\×\exp (-j\widehat{\mathrm{\θ}}\×(240-k)),k=1,...,448$

E wherein _nbe to receive data described in n time slot,

for data after described compensation.

Preferably; phase compensating method described above; described phase compensating method is applied to TD SDMA TD-SCDMA system; described impulse response data comprise front channel impulse response sequence, front data symbol sequence, protection section sequence, rear data symbol sequence and rear channel impulse response sequence, and the number of chips of described front channel impulse response sequence and described rear channel impulse response sequence is 128.

Preferably, phase compensating method described above, when described signal data is n time slot, the position in main footpath described in the described impulse response data of described judgement, the computing formula that obtains described main path position coordinate is:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\∈(\mathrm{1,2}...128)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$

Index wherein _maxfor described main path position coordinate, i is the chip position of described front channel impulse response sequence and described rear channel impulse response sequence; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position, $G_i\left(\underset{i\∈(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$ Refer to when (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

Preferably, phase compensating method described above, according to described main path position coordinate, described time gate limit value and/or described power threshold, the computing formula of calculating the described useful path positions coordinate of acquisition is:

index _max-ξ≤j≤index _max+ξ

And/or, (| h _n(j) | ²+ | h _n+1(j) | ²)>=(| h _n(index _max) | ²+ | h _n+1(index _max) | ²) σ, j=1,2...128

Wherein, j is described useful path positions coordinate, and ξ is described time gate limit value, and σ is described power threshold; h _n(j) be the front channel impulse response at described useful path positions coordinate place, h _n+1(j) be the rear channel impulse response at described useful path positions coordinate place; h _n(index _max) be the front channel impulse response at described main path position coordinate place, h _n+1(index _max) be the rear channel impulse response at described main path position coordinate place.

Preferably, phase compensating method described above, describedly utilizes described useful path positions coordinate, and the computing formula of calculating the average phase deviation of the described rear numerical chracter sequence of impulse response data described in n time slot is:

θ _j＝arg(h _n+1(j)/h _n(j))/864，j＝0，1，..，N-1

And $\widehat{\mathrm{\θ}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\Σ}}}{\mathrm{\θ}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response of j position, h _n(j) for described useful path positions coordinate is the front channel impulse response of j position,

described average phase deviation for described signal data.

Preferably, phase compensating method described above, after the compensation of described rear numerical chracter sequence being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\×\exp (-j\widehat{\mathrm{\θ}}\×(512-k)),k=1,...,1008$

E wherein _nbe described in n time slot after numerical chracter sequence,

for data after described compensation.

The present invention provides a kind of phase compensation device of receiver on the other hand, comprising:

Useful footpath extraction unit, for carrying out according to received signal data the impulse response data that obtain after channel impulse response, judge the position in the useful footpath of described impulse response data, obtain useful path positions coordinate, described useful footpath is the chip that makes the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach a preset range;

Phase calculation unit, for utilizing described useful path positions coordinate, calculates the average phase deviation of described signal data;

Phase compensation unit, carries out phase compensation according to described average phase deviation to described signal data.

Preferably, phase compensation device described above, described useful footpath extraction unit further comprises: main path position extracts subelement, for judging the position in the main footpath of described impulse response data, obtain main path position coordinate, described main footpath is to make the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach maximum chip; Set subelement, time gate limit value and/or power threshold for default described useful footpath with respect to corresponding relation between described main footpath, determine described preset range according to described time gate limit value and/or power threshold; Useful path positions computation subunit, for according to described main path position coordinate, described time gate limit value and/or described power threshold, calculates and obtains described useful path positions coordinate.

Preferably, phase compensation device described above, described phase compensation device is applied to multimedia broadcasting Single Frequency Network system TD-MBSFN, and described impulse response data comprise front channel impulse response sequence, data symbol sequence and rear channel impulse response sequence.

Preferably; phase compensation device described above; described phase compensation device is applied to TD SDMA TD-SCDMA system, and described impulse response data comprise front channel impulse response sequence, front data symbol sequence, protection section sequence, rear data symbol sequence and rear channel impulse response sequence.

At least one in technique scheme has following beneficial effect:

Utilize useful footpath to carry out phase estimation and phase compensation, can improve the precision of phase estimation, and the performance that improves receiver;

Described method and apparatus is simple, not only can meet the sharply increase of Future Multimedia application to 3G wireless high-speed data business demand, and cost is low, therefore can provide strong support for large-scale commercial application.

Accompanying drawing explanation

Fig. 1 is the data structure schematic diagram of TD-MBMS system;

Fig. 2 is the structural representation of the normal time slot of TD-MBMS system;

Fig. 3 is the TD-MBMS system structural representation of gap in short-term;

Fig. 4 is the concrete pie graph of training sequence (Preamble);

Fig. 5 is in TD-MBMS system, the data frame structure schematic diagram of received data;

Fig. 6 is in TD-MBMS system, the data structure schematic diagram of received data n time slot;

Fig. 7 is the schematic flow sheet of phase compensating method described in the specific embodiment of the invention;

Fig. 8 is the structural representation of phase compensation device described in the specific embodiment of the invention;

Fig. 9 is the structural representation of TD-SCDMA system data;

Figure 10 is in TD-SCDMA system, the structural representation of receiver received signal data n time slot.

Embodiment

For making the object, technical solutions and advantages of the present invention clearer, describe the present invention below in conjunction with the accompanying drawings and the specific embodiments.

Phase compensating method based on balancing technique described in the specific embodiment of the invention and device, phase estimation is carried out in the useful footpath of extracted data signaling channel impulse response, abandon the channel impulse response path that confidence level is not high, therefore the precision of phase estimation can be improved.

Described in the specific embodiment of the invention, phase compensating method and device can be applied to TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) (TD-SCDMA) system, time-division multimedia broadcast multicast service (TD-MBMS) system etc. of wireless telecommunication system, when phase estimation, adopt the useful footpath of channel impulse response to carry out phase estimation, for those systems provide accurate phase compensating method.

In the specific embodiment of the invention, the useful footpath of described channel impulse response, it is the chip that makes the front channel impulse response of impulse response data and the power of rear channel impulse response and reach a preset range, also before chip, the power of channel impulse response and while reaching in this preset range, confidence level and accuracy are higher, therefore make the precision of phase estimation improve.

The extracting method in concrete this useful footpath, can adopt the position of first extracting main footpath in channel impulse response, according to main footpath, further determines the mode of useful path positions.

The power that this main footpath is front channel impulse response and rear channel impulse response and reach maximum chip, for further determining useful path positions, in the specific embodiment of the invention, be preset with time gate limit value and/or power threshold with respect to corresponding relation between main footpath with footpath, according to this time gate limit value and/or power threshold, determine preset range, also define the channel impulse response that can reach with respect to main footpath with footpath.

Below will take TD-MBMS system as example, phase compensating method described in the specific embodiment of the invention and device will be elaborated.

As shown in Figure 1, TD-MBMS adopts full descending time slot, comprises in short-term gap 1 and normal time slot 2, and the length of gap 1 is 352 chips in short-term, is used for MBMS transmission control signal; And normal time slot 2 takies all the other 7 descending time slot length, each descending time slot length is 864 chips.

If Fig. 2 is the structure chart of the normal time slot 2 of TD-MBMS system, this normal time slot 2 comprises the training sequence (Preamble) of 96 chips and the data symbol (Data symbols) of 768 chips.

If Fig. 3 is the TD-MBMS system structure chart of gap 1 in short-term, this in short-term gap 1 comprise the training sequence (Preamble) of 96 chips and the data symbol (Data symbols) of 256 chips.

If Fig. 4 is the concrete pie graph of training sequence (Preamble), this has the training sequence of 96 chips, and wherein front 32 chips are one section of repetitions of rear 64 chips, therefore for TD-MBMS system, and 64 chips after only need adopting while carrying out channel estimating.

Consult Fig. 5, receiver received signal data sequence e _nrepresent, wherein e _{n, a}for representing the training sequence of received signal n time slot, e _{n, b}for representing the data division of received signal n time slot, as Fig. 5, receiver received signal data sequence is by e ₁to e _n, sequentially arrange.In addition, consult again Fig. 5, at received signal data n time slot e _ntwo ends all there is training sequence, be also e _nboth the training sequence e that had comprised this time slot (n time slot) _{n, a}with data division e _{n, b}, also comprise the training sequence e of next time slot (n+1 time slot) _{n, c}, and e _{n, c}e namely _{n+1, a}.

Consult Fig. 6, as received signal data n time slot e _nduring for normal time slot, the signal data of this n time slot comprises the rear training sequence of the front training sequence of 96 chips, the data symbol of 768 chips and 96 chips; As received signal data n time slot e _nduring for gap in short-term, the signal data of this n time slot comprises the rear training sequence of the front training sequence of 96 chips, the data symbol of 256 chips and 96 chips.

Phase compensating method and device described in the specific embodiment of the invention, after receiving the reception signal of above-mentioned n time slot, according to the impulse response data that obtain after channel impulse response, and to after the denoising of impulse response data, obtain forward and backward channel impulse response h _n, h _n+1, judge that afterwards the useful footpath of signal data is in forward and backward channel impulse response h _n, h _n+1position, utilize useful path positions, calculate average phase deviation, can signal data being carried out to accurate phase compensation.

Below will be described in detail phase compensating method described in the specific embodiment of the invention.

Fig. 7 is the schematic flow sheet of phase compensating method described in the specific embodiment of the invention, consults Fig. 7, and described phase compensating method, from step S701, comprising:

Step S702, receives n time slot signal data and carries out the impulse response data after channel impulse response, and these impulse response data comprise front channel impulse response sequence, data symbol and rear channel impulse response sequence; Consult Fig. 6, wherein when no matter this n time slot is still gap in short-term of normal time slot, this forward and backward channel impulse response sequence is respectively 96 chips, consult Fig. 4, channel impulse response due to front 32 chips is the repetition of rear 64 chip channel impulse responses again, therefore in forward and backward channel impulse response sequence, the chip for channel estimating is only rear 64 chips, is on the contrary, and rear 64 chips in forward and backward channel impulse response sequence are for channel estimating;

Step S703, judges that useful footpath is in the position of forward and backward channel impulse response sequence, obtains useful path positions coordinate;

In phase compensating method described in the specific embodiment of the invention, judge the method for useful footpath below the position of forward and backward channel impulse response sequence adopts:

First, judge that the main footpath of n time slot signal data is in the position of forward and backward channel impulse response sequence; Wherein can adopt formula (1) for defining main path position:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\∈(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)---\left(1\right)$

Wherein: index _maxfor described main path position coordinate, i is the chip position of front channel impulse response sequence and rear channel impulse response sequence, by upper this forward and backward channel impulse response sequence, for total number of chips of channel estimating, is 64; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position, $G_i\left(\underset{i\∈(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$ Refer to when (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

By above-mentioned formula (1), obtain this main path position coordinate index _maxfor making (| h _n(i) | ²+ h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

Afterwards, time gate limit value and/or the power threshold of corresponding relation between the Yu Zhu footpath, useful footpath of preset channel impulse response; If setup times threshold value is ξ, power threshold is σ, wherein 0 < σ≤1.

This useful footpath can be corresponding to the required formula that meets certain hour corresponding relation in main footpath:

index _max-ξ≤j≤index _max+ξ (2)

Wherein j is used for representing useful path positions coordinate, and j is 1,2 ..., the numerical value in 64.

And this useful footpath can be corresponding to the required formula that meets certain power corresponding relation in main footpath:

(|h _n(j)| ²+|h _n+1(j)| ²)≥(|h _n(index _max)| ²+|h _n+1(index _max)| ²)σ，，j＝1，2...64 (3)

It will be appreciated by those skilled in the art that, according to the data characteristic of received data signal, useful footpath be can define and formula (2) or formula (3) only met corresponding to main footpath, or define useful footpath and need to meet formula (2) and (3) corresponding to main footpath simultaneously, to extract satisfactory useful footpath, obtain the position coordinates in useful footpath.And for defining time gate limit value ξ and the power threshold σ in useful footpath, specifically can be according to the property settings such as frequency deviation of signal data.

Like this, by above-mentioned method, can obtain a series of useful footpaths that the definition of useful footpath requires that meet, the position coordinates in those useful footpaths can be used j ₀, j ₁..., j _n-1represent, and N is less than 64, all useful path positions coordinates is assigned to vectorial index from small to large, obtain the data vector of useful path positions coordinate:

index＝(index ₀，index ₁，...，index _N-1) (4)

Especially, when ξ=0, σ=1 o'clock, the useful footpath of extracting is main footpath, also only utilizes the main footpath of impulse response data to carry out phase estimation.

Like this, according to the useful path positions coordinate of above-mentioned acquisition, for phase estimation, phase compensating method continues to carry out following step described in the specific embodiment of the invention:

Step S704, utilizes the useful path positions coordinate that obtains, and calculates the average phase deviation of n time slot impulse response data;

When these n time slot signal data are normal time slot, useful footpath coordinate is index _ithe phase deviation of position is:

θ _i＝arg(h _n+1(index _i)/h _n(index _i))/864，i＝0，1，..，N-1 (5)

When these n time slot signal data are during for gap in short-term, useful footpath coordinate is index _ithe phase deviation of position is:

θ _i＝arg(h _n+1(index _i)/h _n(index _i))/352，i＝0，1，..，N-1 (6)

Wherein arg (.) is for asking phase function, θ _iexpression calculates according to i footpath in N useful footpath the phase deviation obtaining.

According to the phase deviation at each useful path positions place of above-mentioned formula (5) or (6) acquisition, the average phase deviation that calculates n time slot signal data is:

$\widehat{\mathrm{\&theta;}}=\frac{1}{N}\underset{i=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_i---\left(7\right)$

The average phase deviation obtaining according to above-mentioned formula (7) like this, can carry out phase compensation to n time slot data, carries out following step:

Step S705, according to described average phase deviation to receive n time slot signal data e _ncarry out phase compensation;

Wherein, as received signal data e _nduring for normal time slot, obtain the signal data after phase compensation

for:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(496-k)),k=1,...,960---\left(8\right)$

As received signal data e _nduring for gap in short-term, obtain the signal data after phase compensation

for:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(240-k)),k=1,...,448---\left(9\right)$

Step S706, finishes.

To sum up, above-mentioned phase compensating method, in the channel impulse response of employing received signal data, phase estimation is carried out in power path large, that confidence level is higher, therefore can improve the precision of phase estimation, improves the performance of receiver.

In addition, the present invention also provides a kind of phase compensation device based on balancing technique on the other hand, and Fig. 8 is the structural representation of phase compensation device described in the specific embodiment of the invention, consults Fig. 8, and this phase compensation device specifically comprises:

Useful footpath extraction unit 10, for carrying out according to received signal data the impulse response data that obtain after channel impulse response, judge the position in the useful footpath of described impulse response data, obtain useful path positions coordinate, described useful footpath is the chip that the channel impulse response in described impulse response data reaches a preset range;

Take this phase compensation device is applied to TD-MBMS system as example, this useful footpath extraction unit 10 n time slot signal data e that receive _nfor normally time slot or in short-term gap, this signal data e _nstructure form as shown in Figure 5 and Figure 6.

In phase compensation device described in the specific embodiment of the invention, this useful footpath extraction unit 10 further comprises:

Main path position extracts subelement 11, for judging the position in the main footpath of described impulse response data, obtains main path position coordinate, and described main footpath is to make the channel impulse response in described impulse response data reach maximum chip.

When the main footpath that judges n time slot impulse response data is in the forward and backward channel impulse response sequences h of n time slot _n(i), h _n+1(i) position, adopts above-mentioned formula (1) for defining main path position:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\&Element;(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)---\left(1\right)$

Wherein: index _maxfor described main path position coordinate, i is the chip position of front channel impulse response sequence and rear channel impulse response sequence, by upper this forward and backward channel impulse response sequence, for total number of chips of channel estimating, is 64; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position, $G_i\left(\underset{i\&Element;(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$ Be instigate (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

By above-mentioned formula (1), obtain this main path position coordinate index _maxfor making (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, the i value of 2...64 maximum.

Set subelement 12, for time gate limit value and/or the power threshold of corresponding relation between the Yu Zhu footpath, useful footpath of preset channel impulse response; If setup times threshold value is ξ, power threshold is σ, wherein 0 < σ≤1.

Useful path positions computation subunit 13, for according to described main path position coordinate, described time gate limit value and/or described power threshold, calculates and obtains described useful path positions coordinate.

Above-mentioned formula (2) and (3) can be consulted corresponding to the required corresponding relation formula that meets certain hour and/or power in main footpath in this useful footpath, are also that useful footpath j is defined as and satisfies condition:

Index _max-ξ≤j≤index _max+ ξ, and/or

(|h _n(j)|2+|h _n+1(j)| ²)≥(|h _n(index _max)| ²+|h _n+1(index _max)| ²)σ，，j＝1，2...64

Wherein j is used for representing useful path positions coordinate, and j is 1,2 ..., the numerical value in 64.

By above-mentioned method, can obtain a series of useful footpaths that the definition of useful footpath requires that meet, the position coordinates in those useful footpaths can be used j ₀, j ₁.., j _n-1represent, and N is less than 64, all useful path positions coordinates are assigned to vectorial index from small to large, obtain the data vector of useful path positions coordinate: index=(index ₀, index ₁..., index _n-1).

Phase calculation unit 20, the useful path positions coordinate for utilizing useful footpath extraction unit 10 to obtain, calculates signal data e _naverage phase deviation; The computing formula of this average phase deviation is consulted shown in above-mentioned formula (5)-(6), also as signal data e _nduring for normal time slot, useful footpath coordinate is index _ithe phase deviation of position is:

θ _i＝arg(h _n+1(index _i)/h _n(index _i))/864，i＝0，1，..，N-1

As signal data e _nduring for gap in short-term, useful footpath coordinate is index _ithe phase deviation of position is:

θ _i＝arg(h _n+1(index _i)/h _n(index _i))/352，i＝0，1，..，N-1

And according to the phase deviation at above-mentioned each useful path positions place, calculate signal data e _naverage phase deviation be:

$\widehat{\mathrm{\&theta;}}=\frac{1}{N}\underset{i=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_i$

Phase compensation unit 30, the average phase deviation obtaining according to phase calculation unit 20

to signal data e _ncarry out phase compensation, wherein carry out institute's picked up signal data after phase compensation

computing formula as shown in formula (8) and (9), do not repeat them here.

Phase compensation device described in the specific embodiment of the invention, utilizes main useful footpath to carry out phase estimation and phase compensation, can improve the precision of phase estimation, and the performance that improves receiver, especially less for footpath number, the fading channel that phase deviation is larger, this advantage is particularly evident; In addition described apparatus structure is simple, not only can meet the sharply increase of Future Multimedia application to 3G wireless high-speed data business demand, and cost is low, therefore can provide strong support for large-scale commercial application.

Those skilled in the art of the present invention are appreciated that, core concept based on technical solution of the present invention, in the phase estimation of field of wireless communication, extract the higher useful footpath of master of confidence level in phase estimation and be used for carrying out phase estimation and compensation, can not limit the TD-MBMS system that is applied to, phase compensating method of the present invention and device can also be applied to TD-SCDMA system etc.

In TD-SCDMA system; received data wherein a time slot data structure schematic diagram as shown in Figure 9, this wherein a time slot comprise protection section (GP) part of the front data division of 352 chips, the rear data division of the training sequence of 144 chips, 352 chips and 16 chips.And for TD-SCDMA system, in the training sequence of this 144 chip, front 16 chips are one section of repetitions of rear 128 chips, so channel estimating only need adopt rear 128 chips.

In addition, in TD-SCDMA system, receiver received signal data n time slot e _ndesign feature as shown in figure 10, this n time slot e _nthe front data symbol of signal data and the training sequence of one 144 chips join, and rear data symbol also joins with the training sequence of one 144 chips, according to this design feature, for n time slot e _nwith n+1 time slot e _n+1reception signal, can adopt n time slot e simultaneously _ntraining sequence and n+1 time slot e _n+1training sequence make phase estimation, utilize the phase estimation result that obtains respectively in order to compensate n time slot e _nrear data symbol part and n+1 time slot e _n+1front data symbol part.

According to above-mentioned, described in the specific embodiment of the invention, phase compensating method and application of installation are in TD-SCDMA system, after receiving the reception signal of n and n+1 time slot as shown in figure 10, according to the impulse response data that obtain after channel impulse response, and to after the denoising of impulse response data, obtain forward and backward channel impulse response h _n, h _n+1, be also respectively n time slot e _ntraining sequence and n+1 time slot e _n+1the impulse response data of training sequence, judge that afterwards the useful footpath of signal data is in forward and backward channel impulse response h _n, h _n+1position, utilize useful path positions, calculate average phase deviation, can signal data being carried out to accurate phase compensation.

Wherein, this judges the method in useful footpath, can be identical with the method in above-mentioned TD-MBMS system, first, judge that main footpath is in the position of forward and backward channel impulse response sequence; According to the data structure characteristic of TD-SCDMA system, can adopt formula (10) for defining main path position:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\&Element;(\mathrm{1,2}...128)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)---\left(10\right)$

By formula (10), obtain main path position coordinate index _maxeven, also (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...128 is maximum.

Afterwards, time gate limit value and/or the power threshold of corresponding relation between the Yu Zhu footpath, useful footpath of preset channel impulse response; If setup times threshold value is ξ, power threshold is σ, wherein 0 < σ≤1.

Formula (2) is consulted corresponding to the required corresponding relation that meets certain hour in main footpath in this useful footpath:

index _max-ξ≤j≤index _max+ξ

Wherein j is used for representing useful path positions coordinate, and j is 1,2 ..., the numerical value in 128.

And this useful footpath can be corresponding to the required formula that meets certain power corresponding relation in main footpath:

(|h _n(j)| ²+|h _n+1(j)| ²)≥(|h _n(index _max)| ²+|h _n+1(index _max)| ²)σ，，j＝1，2...128 (11)

Like this, can determine that useful path positions coordinate is for meeting the coordinate values of above-mentioned formula (2) and/or formula (11), the position coordinates in those useful footpaths can be used j ₀, j ₁..., j _n-1represent, and N is less than 128, all useful path positions coordinates is assigned to vectorial index from small to large, obtain the data vector of useful path positions coordinate:

index＝(index ₀，index ₁，...，index _N-1)

Especially, when ξ=0, σ=1 o'clock, the useful footpath of extracting is main footpath, also only utilizes the main footpath of impulse response data to carry out phase estimation.

Afterwards, according to the data vector index of the useful path positions coordinate of above-mentioned acquisition, carry out phase estimation and be:

θ _i＝arg(h _n+1(index _i)/h _n(index _i))/864，i＝0，1，..，N-1 (12)

Wherein the implication of each parameter is identical with formula (6), and consults formula (7) and can obtain n time slot e _nrear data symbol part and n+1 time slot e _n+1the average phase deviation of front data symbol part

Finally according to formula (13) according to this average phase deviation

to n time slot e _nrear data symbol part and n+1 time slot e _n+1front data symbol partly carry out phase compensation, this formula (13) is:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(512-k)),k=1,...,1008---\left(13\right)$

So specific descriptions based on above-mentioned, phase compensating method of the present invention and device can be applied to TD-SCDMA system, it will be appreciated by those skilled in the art that, core concept based on technical solution of the present invention, phase compensating method of the present invention and device can be only for being applied to above-mentioned TD-MBMS and TD-SCDMA system, can also be applied to other system equally, in other system, extracting the concrete grammar in useful footpath can set according to the architectural characteristic of corresponding system data, those skilled in the art are according to ordinary skill in the art knowledge, can obtain the computational methods that other system extracts useful footpath, at this, describe in detail no longer one by one.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (16)

1. a phase compensating method for receiver, is characterized in that, described phase compensating method comprises:

Receive a signal data and carry out the impulse response data that obtain after channel impulse response, judge the position in useful footpath in described impulse response data, obtain useful path positions coordinate, described useful footpath is the chip that makes the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach a preset range;

Utilize described useful path positions coordinate, calculate the average phase deviation of described signal data;

According to described average phase deviation, described signal data is carried out to phase compensation; Wherein,

The position in useful footpath in the described impulse response data of described judgement, the step that obtains described useful path positions coordinate specifically comprises:

Judge the position in main footpath in described impulse response data, obtain main path position coordinate, described main footpath is to make the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach maximum chip;

Described preset range, with respect to time gate limit value and/or the power threshold of corresponding relation between described main footpath, is determined according to described time gate limit value and/or power threshold in default described useful footpath;

According to described main path position coordinate, described time gate limit value and/or described power threshold, calculate and obtain described useful path positions coordinate.

2. phase compensating method as claimed in claim 1, it is characterized in that, described phase compensating method is applied to multimedia broadcasting Single Frequency Network system TD-MBSFN, described impulse response data comprise front channel impulse response sequence, data symbol sequence and rear channel impulse response sequence, and the number of chips of described front channel impulse response sequence and described rear channel impulse response sequence is 64.

3. phase compensating method as claimed in claim 2, is characterized in that, when described signal data is n time slot, and the position in main footpath described in the described impulse response data of described judgement, the computing formula that obtains described main path position coordinate is:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\&Element;(\mathrm{1,2}...64)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$

Index wherein _maxfor described main path position coordinate, i is the chip position of described front channel impulse response sequence and described rear channel impulse response sequence; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position,

refer to when (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

4. phase compensating method as claimed in claim 3, is characterized in that, according to described main path position coordinate, described time gate limit value and/or described power threshold, the computing formula of calculating the described useful path positions coordinate of acquisition is:

index _max-ξ≤j≤index _max+ξ

And/or, (| h _n(j) | ²+ | h _n+1(j) | ²)>=(| h _n(index _max) | ²+ | h _n+1(index _max) | ²) σ, j=1,2...64

Wherein, j is described useful path positions coordinate, and ξ is described time gate limit value, and σ is described power threshold; h _n(j) be the front channel impulse response at described useful path positions coordinate place, h _n+1(j) be the rear channel impulse response at described useful path positions coordinate place; h _n(index _max) be the front channel impulse response at described main path position coordinate place, h _n+1(index _max) be the rear channel impulse response at described main path position coordinate place.

5. phase compensating method as claimed in claim 4, is characterized in that, when described signal data is normal time slot, describedly utilizes described useful path positions coordinate, and the computing formula of calculating the average phase deviation of described signal data is:

θ _j=arg(h _n+1(j)／h _n(j))／864,j＝0，1，..，N-1

And $\widehat{\mathrm{\&theta;}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response at j place, h _n(j) for described useful path positions coordinate is the front channel impulse response at j place,

described average phase deviation for described data;

Wherein, described normal time slot comprises the training sequence of 96 chips and the data symbol of 768 chips.

6. phase compensating method as claimed in claim 5, is characterized in that, when described signal data is normal time slot, after the compensation of described signal data being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(496-k)),k=1,...,960$

E wherein _nbe the signal data that n time slot receives,

for data after described compensation, k is chip index index;

Wherein, described normal time slot comprises the training sequence of 96 chips and the data symbol of 768 chips.

7. phase compensating method as claimed in claim 4, is characterized in that, described signal data is during for gap in short-term, describedly utilizes described useful path positions coordinate, and the computing formula of calculating the average phase deviation of described signal data is:

θ _j=arg(h _n+1(j)／h _n(j))／352,j=0，1，..，N-1

And $\widehat{\mathrm{\&theta;}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response of j position, h _n(j) for described useful path positions coordinate is the front channel impulse response of j position,

described average phase deviation for described signal data;

Wherein, described gap in short-term comprises the training sequence of 96 chips and the data symbol of 256 chips.

8. phase compensating method as claimed in claim 7, is characterized in that, described signal data is during for gap in short-term, and after the compensation of described signal data being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(240-k)),k=1,...,448$

E wherein _nbe the signal data that n time slot receives,

for data after described compensation, k is chip index index;

Wherein, described gap in short-term comprises the training sequence of 96 chips and the data symbol of 256 chips.

9. phase compensating method as claimed in claim 1; it is characterized in that; described phase compensating method is applied to TD SDMA TD-SCDMA system; described impulse response data comprise front channel impulse response sequence, front data symbol sequence, protection section sequence, rear data symbol sequence and rear channel impulse response sequence, and the number of chips of described front channel impulse response sequence and described rear channel impulse response sequence is 128.

10. phase compensating method as claimed in claim 9, is characterized in that, when described signal data is n time slot, and the position in main footpath described in the described impulse response data of described judgement, the computing formula that obtains described main path position coordinate is:

${\mathrm{index}}_{\max }=G_i\left(\underset{i\&Element;(\mathrm{1,2}...128)}{\max }({\left|h_n\left(i\right)\right|}^2+{\left|h_{n+1}\left(i\right)\right|}^2)\right)$

Index wherein _maxfor described main path position coordinate, i is the chip position of described front channel impulse response sequence and described rear channel impulse response sequence; h _n(i) be the front channel impulse response of i position, h _n+1(i) be the rear channel impulse response of i position,

refer to when (| h _n(i) | ²+ | h _n+1(i) | ²), i=1, corresponding i value when 2...64 is maximum.

11. phase compensating methods as claimed in claim 10, is characterized in that, according to described main path position coordinate, described time gate limit value and/or described power threshold, the computing formula of calculating the described useful path positions coordinate of acquisition is:

index _max-ξ≤j≤index _max+ξ

And/or, (| h _n(j) | ²+ | h _n+1(j) | ²)>=(| h _n(index _max) | ²+ | h _n+1(index _max) | ²) σ, j=1,2...128

Wherein, j is described useful path positions coordinate, and ξ is described time gate limit value, and σ is described power threshold; h _n(j) be the front channel impulse response at described useful path positions coordinate place, h _n+1(j) be the rear channel impulse response at described useful path positions coordinate place; h _n(index _max) be the front channel impulse response at described main path position coordinate place, h _n+1(index _max) be the rear channel impulse response at described main path position coordinate place.

12. phase compensating methods as claimed in claim 11, is characterized in that, describedly utilize described useful path positions coordinate, and the computing formula of calculating the average phase deviation of the described rear data symbol sequence of impulse response data described in n time slot is:

θ _j=arg(h _n+1(j)／h _n(j))／864,j=0，1，..，N-1

And $\widehat{\mathrm{\&theta;}}=\frac{1}{N}\underset{j=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_j$

Total number that wherein N is described useful footpath, θ _jfor according to the phase deviation in j footpath in N described useful footpath, h _n+1(j) for described useful path positions coordinate is the rear channel impulse response of j position, h _n(j) for described useful path positions coordinate is the front channel impulse response of j position,

described average phase deviation for described signal data.

13. phase compensating methods as claimed in claim 12, is characterized in that, after the compensation of described rear data symbol sequence being carried out obtaining after phase compensation according to described average phase deviation, data are:

${\hat{e}}_n\left(k\right)=e_n\left(k\right)\&times;\exp (-j\widehat{\mathrm{\&theta;}}\&times;(512-k)),k=1,...,1008$

E wherein _nbe described in n time slot after data symbol sequence,

for data after described compensation, k is chip index index.

The phase compensation device of 14. 1 kinds of receivers, is characterized in that, described phase compensation device comprises:

Useful footpath extraction unit, for carrying out according to received signal data the impulse response data that obtain after channel impulse response, judge the position in the useful footpath of described impulse response data, obtain useful path positions coordinate, described useful footpath is the chip that makes the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach a preset range;

Phase calculation unit, for utilizing described useful path positions coordinate, calculates the average phase deviation of described signal data;

Phase compensation unit, carries out phase compensation according to described average phase deviation to described signal data; Wherein,

Described useful footpath extraction unit further comprises:

Main path position extracts subelement, for judging the position in the main footpath of described impulse response data, obtains main path position coordinate, and described main footpath is to make the front channel impulse response of described impulse response data and the power of rear channel impulse response and reach maximum chip;

Set subelement, time gate limit value and/or power threshold for default described useful footpath with respect to corresponding relation between described main footpath, determine described preset range according to described time gate limit value and/or power threshold;

Useful path positions computation subunit, for according to described main path position coordinate, described time gate limit value and/or described power threshold, calculates and obtains described useful path positions coordinate.

15. phase compensation devices as claimed in claim 14, it is characterized in that, described phase compensation device is applied to multimedia broadcasting Single Frequency Network system TD-MBSFN, and described impulse response data comprise front channel impulse response sequence, data symbol sequence and rear channel impulse response sequence.

16. phase compensation devices as claimed in claim 14; it is characterized in that; described phase compensation device is applied to TD SDMA TD-SCDMA system, and described impulse response data comprise front channel impulse response sequence, front data symbol sequence, protection section sequence, rear data symbol sequence and rear channel impulse response sequence.

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