CN101621824B - Detecting method of coherence of upstream channel and downstream channel in smart antenna system - Google Patents

Abstract

The invention discloses a detecting method of coherence of an upstream channel and a downstream channel in a smart antenna system. An upstream detecting method comprises: transmitting a detection signal by correcting antennae or coupling a network correction port; receiving the detection signal by each antenna and/ or corresponding upstream channel in the smart antenna; multiplying the received detection signals with the upstream channel correct weight of the corresponding channel to obtain a response signal; calculating the same-phase synthesis power and phase-reversal synthesis power of the response signals of any two channels to be detected; comparing the ratio of the same-phase synthesis power and the phase-reversal synthesis power with a set threshold value; if the ratio is more than or equal to the set threshold value, the coherence of the channels reaches the standard, or the coherence can not reach the standard. A downstream detecting method is similar to the upstream detecting method and detects by correcting antennae or coupling a network correction port. The invention not only can obviously improve detection efficiency, but also can accurately judge the coherence of any two channels.

Description

Up and down going channel coherence detection method in the antenna system

Technical field

The present invention relates to passage coherence detection method in the antenna system, relate in particular to up and down going channel coherence detection method in a kind of antenna system.

Background technology

Intelligent antenna technology has become in the mobile communication one of the most attractive technology.The smart antenna array antenna of challenging an opponent to a fight when two armies meet again, it adopts space division multiple access technique, utilizes the difference of signal in transmission direction, with same frequency or same time slot, come with the signal distinguishing of code channel, maximally utilises limited channel resource.Compare with non-directional antenna, the antenna gain of its uplink and downlink link improves greatly, has reduced transmitted power level, has improved signal to noise ratio, has overcome the influence of Channel Transmission decline effectively.Intelligent antenna technology utilizes the spatial character and the Digital Signal Processing of signal transmission; Can realize up reception signal high specific merging, the estimation of figuration weight vector and downlink signal beam figuration, thereby reach the purpose that reduces interference, increase capacity, expansion covering, improves communication quality, reduction transmitting power and raising wireless data transmission rate.

The coherence is one of important indicator of weighing the array antenna performance between each passage.For the up link of the communication system of having used array antenna; In order to realize that each data feedback channel receives the high specific merging of signal; Reach purposes such as improving signal to noise ratio and inhibition interference; Coherence between each data feedback channel must meet the demands, to realize the high coefficient correlation between the corresponding reception signal; For the down link of array antenna system; In order to realize wave beam forming to a certain user; Be that each down going channel transmits and can merge at this user equipment side homophase; Reach wave beam and improve purposes such as signal to noise ratio and inhibition interference, the coherence between each down going channel must meet the demands, to realize the high coefficient correlation between corresponding the transmitting.

Publication number is that the one Chinese patent application of CN1777071A provides a kind of passage coherence method of testing that is used for intelligent antenna base station; The a plurality of data feedback channels or a plurality of down going channel that are used for testing base station; Comprise with a passage as the benchmark passage; Another passage is closed remaining passage as passage to be measured; Keep the weights of benchmark passage constant; Change the weights of passage to be measured; Make the anamorphic zone internal power minimum and should be with the internal power minimum value, the phase place of weights is added or deduct 180 ° and write down anamorphic zone internal power values at this moment as second performance number as first performance number; According to said second and the difference of first performance number judge the coherence between passage to be measured and the benchmark passage.This application is tested the coherence between each passage to be measured and the benchmark passage successively; In the test process of single, only benchmark passage and a certain passage work to be measured, and rest channels is closed; All need the benchmark passage to transmit separately or receive signal for each passage to be measured; The number of repetition of above-mentioned test process is relevant with port number to be measured, if port number to be measured more for a long time, then certainly exists shortcomings such as testing efficiency is low; And each passage to be measured all is to test with the benchmark combination of channels, is difficult to accurately judge the coherence between two passages to be measured.And, in test process, need constantly the weights of change passage to be measured to confirm the minimum value of band internal power, this has increased the complexity of handling undoubtedly, and the accuracy of its result is also not enough.

Summary of the invention

In view of this; Main purpose of the present invention is to provide up and down going channel coherence detection method in a kind of antenna system; Through test signal once send the measurement can accomplish antenna to be measured, improve testing efficiency, coherence measurement is relatively accurate between the passage.

In order to realize the foregoing invention purpose, main technical schemes of the present invention is:

Data feedback channel coherence detection method in a kind of antenna system comprises:

Proofread and correct a mouthful emitting detection signal through proofreading and correct antenna or coupling network, each antenna and/or its corresponding data feedback channel receive said detection signal in the smart antenna;

The detection signal that receives and the data feedback channel corrected weight value of respective channel multiply each other, and signal meets with a response;

Calculate the same power and the synthetic power of anti-phase of being combined to of any two channel response signals to be measured; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard more than or equal to setting threshold, otherwise the coherence of two passages is not up to standard.

Preferably, the detection signal of reception is detected by the signal processing unit of smart antenna.

Preferably, said be combined to power be with get behind two channel response signal plus to be measured its mould square; The synthetic power of said anti-phase be with get behind two channel response signal subtractions to be measured its mould square.

Preferably, proofreading and correct an antenna or coupling network correction mouthful detection signal of launching is pseudo random sequence symbol or orthogonal sequence symbol.

Down going channel coherence detection method in a kind of antenna system comprises:

Based on the corresponding spreading code of each down going channel in the smart antenna, generate mutually orthogonal chip-level spread spectrum signal sequence based on prosign level detection signal sequence, and launch simultaneously through antenna and/or its corresponding down going channel;

Proofread and correct antenna or coupling network in the smart antenna and proofread and correct a mouthful signal that receives each antenna and/or the emission of its corresponding down going channel;

Detect and proofread and correct an antenna or a coupling network correction mouthful signal that is received; Spreading code and the symbol level detection signal despreading corresponding based on each down going channel go out each down going channel symbol level burst; Multiply each other respectively with the down going channel corrected weight value of each passage, signal meets with a response;

Calculate the same power and the synthetic power of anti-phase of being combined to of the symbol level burst of any two down going channel to be measured institutes despreading; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard more than or equal to setting threshold, otherwise the coherence of two passages is not up to standard.

Preferably, said be combined to power be with get behind two channel response signal plus to be measured its mould square; The synthetic power of said anti-phase be with get behind two channel response signal subtractions to be measured its mould square.

Preferably, said correction antenna or coupling network are proofreaied and correct the signal processing unit detection of mouthful signal that is received by smart antenna.

Preferably, said spreading code is the walsh code of quadrature.

The present invention utilizes correction antenna or the coupling network correction mouth in the smart antenna to launch or the acceptance test signal; Signal emission through once can be accomplished each antenna channels coherence's detection; The present invention directly detects passage to be measured, and its testing result has directly been reacted the coherence of antenna channels.Therefore, the present invention not only detection efficiency obviously improves, and can accurately judge the coherence between any two passages, have real-time, be easy to advantages such as Project Realization.

Description of drawings

Fig. 1 is the flow chart of data feedback channel coherence detection method in the antenna system of the embodiment of the invention;

Fig. 2 is the flow chart of down going channel coherence detection method in the antenna system of the embodiment of the invention.

Embodiment

Basic thought of the present invention is: in the existing antenna system, need select a reference antenna passage for use, only remaining antenna channels to be measured could realize antenna channels coherence's detection, and testing efficiency is lower, and the measurement result accuracy is also not high enough.Be directed to this; The present invention utilizes correction antenna and the coupling network correction mouth in the smart antenna to launch or the acceptance test signal; Signal emission through once can be accomplished each antenna channels coherence's detection; The present invention directly detects passage to be measured, and its testing result has directly been reacted the coherence of antenna channels.Detection efficiency of the present invention is high, can ensure the accuracy of detection, have real-time, be easy to advantage such as Project Realization.Describe the present invention below in conjunction with accompanying drawing.

Fig. 1 is the flow chart of data feedback channel coherence detection method in the antenna system of the embodiment of the invention, and as shown in Figure 1, data feedback channel coherence detection method may further comprise the steps in the antenna system of the embodiment of the invention:

Step 101: proofread and correct a mouthful emitting detection signal through proofreading and correct antenna or coupling network, each antenna and/or its corresponding data feedback channel receive said detection signal in the smart antenna.

For smart antenna; In order to realize the purpose of wave beam forming; Must proofread and correct between the antenna channels,, have only compensation through amplitude, phase place to compensate the inconsistency of amplitude, phase place between each data feedback channel; Could realize the relevant fully of signal, could realize that the transmitting power of main beam reaches maximum.In order to guarantee the coherence of signal, smart antenna need be adjusted signal through the channel characteristic of antenna, makes it to reach the purpose of homophase and/or same frequency.Channel characteristic is relevant with the length of cable that connects antenna and coupler, antenna polarization characteristics etc., and can obtain these channel characteristics through the measurement of correlation means is that data feedback channel is proofreaied and correct weight vector, can be expressed as $w_{\mathrm{UL}}={[w_{\mathrm{UL}}^{\left(1\right)},w_{\mathrm{UL}}^{\left(2\right)},...,w_{\mathrm{UL}}^{\left(K\right)}]}^T;$ Wherein, K is effective uplink antenna port number,

K=1,2 ..., K;

Be w _UL ^(k)Amplitude; () ^TExpression complex vector or transpose of a matrix.Data feedback channel is proofreaied and correct weight vector w _UL ^(k)Show as plural number on the mathematics.w _UL ^(k)Can regulate phase place and/or amplitude through the signal of passage.w _UL ^(k)Can obtain through antenna system, it is a known quantity.

Correction antenna or coupling network through array antenna are proofreaied and correct mouthful a certain detection signal sequence of emission, and all uplink antenna passages to be measured receive this burst simultaneously.A detection signal sequence of proofreading and correct the mouth emission through the correction antenna or the coupling network of array antenna can be pseudorandom (PN) sequence signal or orthogonal sequence signal, and lasting duration is P.The burst that all uplink antenna passages to be measured receive simultaneously is expressed as: $r_{\mathrm{UL}}={[r_{\mathrm{UL}}^{\left(1\right)},r_{\mathrm{UL}}^{\left(2\right)},...,r_{\mathrm{UL}}^{\left(K\right)}]}^T,$ In the formula $r_{\mathrm{UL}}^{\left(k\right)}=\{r_{\mathrm{UL}}^{\left(k\right)}\left(t\right),0\≤t\≤P\}$ The burst that expression data feedback channel k receives, it can be measured through signal processing unit of smart antenna and obtain, and this also is the basic functions that smart antenna can be realized.Need to prove that coupling network is proofreaied and correct all functions that mouth can be realized antenna, it also can launch corresponding signal, but its signal power a little less than.

Step 102: the data feedback channel corrected weight value of the detection signal of reception and respective channel multiplies each other, and signal meets with a response.

With the signal r that antenna channels received _ULProofread and correct weight vector w with the data feedback channel of this antenna channels _ULMultiply each other, promptly obtain the response signal of this antenna channels, the response signal on m antenna channels is r _UL ^(m)(t) w _UL ^(m)This response signal promptly is that smart antenna receives upward signal through the theory signal value behind the respective antenna passage; If the smart antenna design is intact; Signal through each passage should be concerned with so; Can satisfy certain coherence, like this, through directly confirming coherence's situation of antenna channels to the coherent measurement of response signal.

Step 103: same power and the synthetic power of anti-phase of being combined to that calculates any two channel response signals to be measured; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard greater than setting threshold, otherwise the coherence of two passages is not up to standard.

The same wattmeter that is combined to that receives signal between up passage m to be measured and the n is shown: $P_1^{(m,n)}=\underset{t=0}{\overset{P}{\mathrm{\Σ}}}{|r_{\mathrm{UL}}^{\left(m\right)}\left(t\right)\·w_{\mathrm{UL}}^{\left(m\right)}+r_{\mathrm{UL}}^{\left(n\right)}\left(t\right)\·w_{\mathrm{UL}}^{\left(n\right)}|}^2,$ M ≠ n, m, n=1,2 ..., K; The synthetic wattmeter of anti-phase that receives signal between up passage m to be measured and the n is shown

If synthesize the ratio of power and be equal to or greater than threshold value with being combined to power and anti-phase, then two up passages to be measured satisfy coherence's designing requirement, otherwise, promptly do not satisfy coherence's designing requirement.If $10\&CenterDot;\mathrm{Lg}\left(\frac{P_1^{(m,n)}}{P_2^{(m,n)}}\right)\&GreaterEqual;{\mathrm{\&Gamma;}}_{\mathrm{UL}},$ Coherence between then up passage m to be measured and the n meets design requirement, wherein Γ _ULBe threshold value, choose Γ during practical application _DL>=15dB; If $10\&CenterDot;\mathrm{Lg}\left(\frac{P_1^{(m,n)}}{P_2^{(m,n)}}\right)<{\mathrm{\&Gamma;}}_{\mathrm{UL}},$ Coherence between then up passage m to be measured and the n does not meet design requirement.Γ _ULChoosing of value is relevant with the relevant parameter and the experience of smart antenna.

The present invention can select two antenna channels to be measured to carry out coherence's detection as required arbitrarily, and detection signal is only sent out the detection that once can realize all antenna channels, and is convenient and swift.

Fig. 2 is the flow chart of down going channel coherence detection method in the antenna system of the embodiment of the invention, and as shown in Figure 2, down going channel coherence detection method may further comprise the steps in the antenna system of the embodiment of the invention:

Step 201:, generate mutually orthogonal chip-level spread spectrum signal sequence based on prosign level detection signal sequence, and launch simultaneously through each antenna and/or its corresponding down going channel according to the corresponding spreading code of each down going channel in the smart antenna.Wherein, spreading code is Walsh (Walsh) sign indicating number of quadrature.

The symbol level detection burst is expressed as s _DL={ s _DL(t), t=1,2 ..., Y}, Y are the symbolic number of sequence; The corresponding spreading code of descending passage k to be measured does $c_{\mathrm{DL}}^{\left(k\right)}=\{c_{\mathrm{DL}}^{\left(k\right)}\left(q\right),q=\mathrm{1,2},...,Q\},$ Q is a spreading factor, adopts the walsh code of quadrature usually; The corresponding chip-level spread spectrum signal sequence of so descending passage k to be measured is expressed as $r_{\mathrm{DL}}^{\left(k\right)}=s_{\mathrm{DL}}^{\left(k\right)}\&CircleTimes;c_{\mathrm{DL}}^{\left(k\right)},$ In the formula

The expression operation of direct product is equivalent to the spread spectrum process.

Step 202: proofread and correct antenna or coupling network in the smart antenna and proofread and correct a mouthful signal that receives each antenna and/or the emission of its corresponding down going channel.All uplink/downlink antenna passages to be measured are launched chip-level spread spectrum signal sequence separately simultaneously.

Step 203: detect and proofread and correct an antenna or a coupling network correction mouthful signal that is received; Spreading code and the symbol level detection signal despreading corresponding according to each down going channel go out each down going channel symbol level burst; Multiply each other respectively with the down going channel corrected weight value of each passage, signal meets with a response.

The correction antenna of array antenna or coupling network are proofreaied and correct mouth can realize the reception to smart antenna detection signal sequence; Detect a correction antenna or a coupling network correction mouthful signal that is received by the smart antenna signal processing unit, the chip level signal sequence table that is detected is shown $\begin{array}{c}{r}_{\mathrm{DL}}=r_{\mathrm{DL}}^{\left(1\right)}+r_{\mathrm{DL}}^{\left(2\right)}+...+r_{\mathrm{DL}}^{\left(K\right)}\\ =s_{\mathrm{DL}}^{\left(1\right)}\&CircleTimes;c_{\mathrm{DL}}^{\left(1\right)}+s_{\mathrm{DL}}^{\left(2\right)}\&CircleTimes;c_{\mathrm{DL}}^{\left(2\right)}+...+s_{\mathrm{DL}}^{\left(K\right)}\&CircleTimes;c_{\mathrm{DL}}^{\left(K\right)}+n\end{array};$ N is additive white Gaussian noise (AWGN) vector in the formula.Proofreading and correct antenna or coupling network correction mouth is the signal receive section of smart antenna, and detecting received signal is the part in its function.

Because spreading code adopts the walsh code of quadrature; And the communication environments between uplink/downlink antenna passage and correction antenna or the coupling network correction mouth is approximately the white Gaussian noise environment; Therefore it is mutually orthogonal basically to proofread and correct antenna or the coupling network correction mouthful chip-level spread spectrum signal sequence that each down going channel that is received is corresponding, and owing to be in-band channel, the multiple access interference problem can be ignored; Therefore, the symbol level burst that goes out of descending passage k to be measured despreading is expressed as $s_{\mathrm{DL}}^{\left(k\right)}\left(t\right)=\underset{q=1}{\overset{Q}{\mathrm{\&Sigma;}}}{r}_{\mathrm{DL}}((t-1)\&CenterDot;Q+q))\&CenterDot;c_{\mathrm{DL}}^{\left(k\right)}\left(q\right)=s_{\mathrm{DL}}\left(t\right),$ T=1,2 ..., Y.

Step 204: same power and the synthetic power of anti-phase of being combined to that calculates the symbol level burst of any two down going channel to be measured institutes despreading; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard greater than setting threshold, otherwise the coherence of two passages is not up to standard.

The same wattmeter that is combined to that receives signal between descending passage m to be measured and the n is shown: $P_1^{(m,n)}=\underset{t=1}{\overset{Y}{\mathrm{\&Sigma;}}}{|r_{\mathrm{DL}}^{\left(m\right)}\left(u\right)\&CenterDot;w_{\mathrm{DL}}^{\left(m\right)}+r_{\mathrm{DL}}^{\left(n\right)}\left(u\right)\&CenterDot;w_{\mathrm{DL}}^{\left(n\right)}|}^2,$ M ≠ n, m, n=1,2 ..., K; The synthetic wattmeter of anti-phase that receives signal between descending passage m to be measured and the n is shown

Down going channel is proofreaied and correct weight vector $w_{\mathrm{DL}}={[w_{\mathrm{DL}}^{\left(1\right)},w_{\mathrm{DL}}^{\left(2\right)},...,w_{\mathrm{DL}}^{\left(K\right)}]}^T,$ w _DLShow as plural number on the mathematics; w _DLCan regulate phase place and/or amplitude through the signal of passage.w _DLBe to guarantee to guarantee when signal arrives antenna the channel parameters that signal frequency and/or phase angle etc. are consistent.Basic w _UL ^(k)Can obtain through antenna system, it is a known quantity.

If synthesize the ratio of power and be equal to or greater than threshold value with being combined to power and anti-phase, then two up passages to be measured satisfy coherence's designing requirement, otherwise, promptly do not satisfy coherence's designing requirement.If $10\&CenterDot;\mathrm{Lg}\left(\frac{P_1^{(m,n)}}{P_2^{(m,n)}}\right)\&GreaterEqual;{\mathrm{\&Gamma;}}_{\mathrm{UL}},$ Coherence between then up passage m to be measured and the n meets design requirement, wherein Γ _ULBe threshold value, Γ during practical application _DL>=15dB; If $10\&CenterDot;\mathrm{Lg}\left(\frac{P_1^{(m,n)}}{P_2^{(m,n)}}\right)<{\mathrm{\&Gamma;}}_{\mathrm{UL}},$ Coherence between then up passage m to be measured and the n does not meet design requirement.Γ _ULChoosing of value is relevant with the relevant parameter and the experience of smart antenna.

The present invention can select two antenna channels to be measured to carry out coherence's detection as required arbitrarily, and detection signal is only sent out the detection that once can realize all antenna channels, and is convenient and swift.

The coherence of up-downgoing antenna channels of the present invention detects, and not only detection efficiency obviously improves, and can accurately judge the coherence between any two passages, have real-time, be easy to advantage such as Project Realization.

The above is merely preferred embodiment of the present invention, is not to be used to limit protection scope of the present invention.

Claims (8)

1. data feedback channel coherence detection method in the antenna system is characterized in that this method comprises:

Proofread and correct a mouthful emitting detection signal through proofreading and correct antenna or coupling network, each antenna and/or its corresponding data feedback channel receive said detection signal in the smart antenna;

The data feedback channel corrected weight value of the detection signal of said reception and respective channel multiplies each other, and signal meets with a response;

Calculate the same power and the synthetic power of anti-phase of being combined to of any two channel response signals to be measured; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard more than or equal to setting threshold, otherwise the coherence of two passages is not up to standard.

2. method according to claim 1 is characterized in that, the detection signal of said reception is detected by the signal processing unit of smart antenna.

3. method according to claim 1 is characterized in that, said be combined to power be with get behind two channel response signal plus to be measured its mould square; The synthetic power of said anti-phase be with get behind two channel response signal subtractions to be measured its mould square.

4. according to each described method in the claim 1 to 3, it is characterized in that it is pseudo random sequence signal or orthogonal sequence signal that said correction antenna or coupling network are proofreaied and correct mouthful detection signal of emission.

5. down going channel coherence detection method in the antenna system is characterized in that this method comprises:

Based on the corresponding spreading code of each down going channel in the smart antenna, generate mutually orthogonal chip-level spread spectrum signal sequence based on prosign level detection signal sequence, and launch simultaneously through antenna and/or its corresponding down going channel;

Proofread and correct antenna or coupling network in the smart antenna and proofread and correct a mouthful signal that receives each antenna and/or the emission of its corresponding down going channel;

Detect and proofread and correct an antenna or a coupling network correction mouthful signal that is received; Spreading code and the symbol level detection signal despreading corresponding based on each down going channel go out each down going channel symbol level burst; Multiply each other respectively with the down going channel corrected weight value of each passage, signal meets with a response;

Calculate the same power and the synthetic power of anti-phase of being combined to of the symbol level burst of any two down going channel to be measured institutes despreading; To compare with the ratio and the setting threshold that are combined to the synthetic power of power and anti-phase; If then the coherence of two passages is up to standard more than or equal to setting threshold, otherwise the coherence of two passages is not up to standard.

6. method according to claim 5 is characterized in that, said be combined to power be with get behind two channel response signal plus to be measured its mould square; The synthetic power of said anti-phase be with get behind two channel response signal subtractions to be measured its mould square.

7. method according to claim 5 is characterized in that, said correction antenna or coupling network are proofreaied and correct the signal processing unit detection of mouthful signal that is received by smart antenna.

8. according to each described method in the claim 5 to 7, it is characterized in that said spreading code is the walsh code of quadrature.

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