CN1333491C - Method and device for correcting array antenna beam pointing error of regional multiple point microwave system - Google Patents

Abstract

The present invention provides an FBFN fuzzy processing method which can automatically correct beam pointing errors and a device thereof, and the present invention can be used for zone multipoint microwave communication systems. According to the distribution of antenna beam pointing errors correspondingly generated by wind force intensity distribution, the correction and processing device of fuzzy beam pointing errors formulates the angular correction quantity of the beam pointing errors. The device which is arranged in a user end of an LMDS system has the function of automatically correcting the beam pointing errors of multibeam array antennae, and the errors of multibeam array antennae are caused by the wind force; the correction and processing device of beam pointing errors measures the direction of base station signals under the influence of the wind force by the multibeam array antennae and forecasts the correction angle of beam pointing errors by 13 basis functions and regular fuzzy basis functions with a correction and calculus method of network beam pointing errors, and the purposes of the present invention are that the main beams of the array antennae are controlled to align the direction of the base station, and the communication quality of the LMDS system is increased. The FBFN processing device has favorable transient response, convergence rate, and minor correction convergence values for beam pointing.

Description

Regional multiple point microwave system array antenna beam pointing error correcting method and device

Technical field

The present invention relates to a kind of regional multiple point microwave system (Local multipointdistributed system that is used for, LMDS) user side (Customer premise equipment, CPE) the automatic correcting process method and apparatus of the beam position error of array antenna, particularly the regression function that adopts the beam position error profile that causes owing to wind-force to design with the fuzzy rule of FBFN carries out beam position error angle modification.Under the system configuration of LMDS, this device can be automatically with the main beam alignment base platform (HUB) of multiple-beam array antenna, improves LMDS system communication quality of (as high wind) when weather conditions are not good immediately.Beam position error correction processing unit is by seeking to (Direction of Arrival that multiple-beam array antenna is measured, DOA) signal is found out the base station signal source direction under windage, again by fuzzy basis function network (Fuzzy Basis FunctionNetwork, FBFN) beam position error correction algorithm prediction beam position error correction angle, make array antenna main beam alignment base platform, to improve communication quality.The FBFN rule produces 13 standard Gauss regression functions and 13 rule bases according to the characteristic that causes the beam position error profile because of wind-force.

Background technology

The antenna of existing LMDS system can't be revised the beam position error automatically, and the beam position error that regular meeting causes because of high wind causes communication quality to reduce or communicating interrupt.

The beam position adjustment of traditional mechanical formula, be to come the registration signal source by the rotable antenna seat with adaptive filter estimation beam position error angle correction value, but mechanical adjustment antenna direction can have delay because of the reaction time of mechanical motor except the time of adjusting, and accuracy is also accurate inadequately.By the mode of array antenna electronic type beam scanning, then can be by revising the phase place of each array antenna unit, make the array antenna main beam immediately, registration signal source accurately, to improve the effect of LMDS system.

The acquisition of array antenna error in pointing angle can be by multibeam signals amplitude ratio method, utilize multiple-beam array antenna, with the overlapping irradiation target of adjacent wave beam, compare two signal amplitude sizes that the different antennae wave beam is received then, in the hope of the direction of base station echo signal.If directly adopt seeking to (DOA) value of estimation directly to carry out the beam position error correction, its beam position error is too big; Or by recursive least-squares (Recursive least square, RLS) the DOA value estimation beam position error correction angle of adaptive filter to measure, the error of its transient response will influence communication quality too greatly, and its convergence rate and beam position error convergence value all still fail to satisfy the instant demand of accurately revising the controlling antenna wave beam to point error of LMDS system.

Summary of the invention

In order to address the above problem, the object of the present invention is to provide automatic correcting process method of a kind of LMDS array antenna beam pointing error and device thereof, the random wave bundle error in pointing that antenna is caused because of high wind can revise immediately automatically and satisfy that the transient response scope is little, fast convergence rate and the low demand of beam position round-off error value.The Lei Shi mode parameter of the Taiwan wind distribution of delivering according to Mr. Huang Wenli of National Central University's building research institute is for example set standard Gauss's regression function of beam position error, by the fuzzy beam position error correction processing unit of FBFN satisfy that the transient response scope is little, fast convergence rate and the low demand of beam position error convergence value.

For achieving the above object, the invention provides a kind of LMDS of being used for array antenna beam pointing error FBFN correcting process method, comprise the following step: receive the base station signal with multiple-beam array antenna at this LMDS user side; Make this base station signal produce the different beam signal of a plurality of intensity of fixed directional in the horizontal direction via a beam forming circuit; From the different beam signal of these a plurality of intensity, select the strongest adjacent two beam signals and subtract each other with produce one seek to the estimation angle signal; Transmitting this seeks to estimation angle signal to FBFN beam position error correction processing unit with the calculating of fuzzy basis function network mode execution angle correction; The angle correction that transmits this calculating produces another wave beam to this beam forming circuit, carries out communication with the main beam alignment base platform of this another wave beam.

Above-mentioned multiple-beam array antenna is the two-dimensional planar array antenna.

The present invention also provides a kind of LMDS of being used for array antenna beam pointing error FBFN correcting process device, comprises: a multiple-beam array antenna is installed in this LMDS user side, in order to receive the base station signal; One beam forming circuit contains power divider and phase-shifter, uses so that this base station signal produces the different beam signal of a plurality of intensity of fixed directional in a horizontal direction; One seeks to estimating apparatus, in order to select the strongest adjacent two beam signals and subtract each other to produce one and seek to the estimation angle signal from the different beam signal of these a plurality of intensity; An and FBFN beam position error correction processing unit, receiving this seeks to the estimation angle signal and with the calculating of fuzzy basis function network mode execution angle correction, and the angle correction of this calculating of transmission is to this beam forming circuit, make this beam forming circuit produce another main beam, main beam alignment base platform carries out communication thus.

Above-mentioned multiple-beam array antenna is the two-dimensional planar array antenna.

Description of drawings

Fig. 1 is embodiments of the invention, and the function of LMDS systems array antenna and beam position error correction processing unit is described;

Fig. 2 is embodiments of the invention, and LMDS systems array controlling antenna wave beam to point error correction processing unit signal flow is described;

Fig. 3 is embodiments of the invention, and 12 two-dimensional planar array antennas that antenna element constituted are described;

Fig. 4 (a) is embodiments of the invention, and 4 wave beams on the xz plane (wave beam 1～wave beam 4) field pattern is described;

Fig. 4 (b) is embodiments of the invention, and adjacent beams difference field pattern corresponding on the xz plane is described;

Fig. 5 (a) is embodiments of the invention, and 2 beam pattern on yz (wave beam 1～wave beam 2) plane are described;

Fig. 5 (b) is embodiments of the invention, and adjacent beams difference field pattern corresponding on the yz plane is described;

Fig. 6 is embodiments of the invention, illustrates that FBFN beam position error correction processing unit proposed by the invention realized by four-layer structure;

Fig. 7 is embodiments of the invention, and the mean value and the variance (1.8,0.86) of the beam position error Gaussian Profile that the first type wind-force causes is described;

Fig. 8 is embodiments of the invention, and the mean value and the variance (2.5,1.7) of the beam position error that the second type wind-force causes is described;

Fig. 9 is embodiments of the invention, and the mean value and the variance (3.5,3.4) of the beam position error Gaussian Profile that the 3rd type wind-force causes is described;

Figure 10 is embodiments of the invention, and the mean value and the variance (4.3,6.9) of the beam position error Gaussian Profile that the 4th type wind-force causes is described;

Figure 11 is embodiments of the invention, and the mean value and the variance (6.1,10.3) of the beam position error Gaussian Profile that the 5th type wind-force causes is described.

Embodiment

Figure 1 shows that the calcspar of the function of the automatic correcting process device of LMDS systems array controlling antenna wave beam to point error proposed by the invention, wherein, the FBFN beam position error correction processing unit 1 that disclose for the present invention in left ash shadow zone, and 2 expression array antennas, 3 expression beam forming circuit, 4 expression DOA estimating apparatus.Its signal flow as shown in Figure 2, receive base station (not shown) signal (step S1) at LMDS user side (not shown) with multiple-beam array antenna 2, via beam forming circuit 3, produce 4 beam signals (step S2) that intensity is different in the horizontal direction, select the strongest adjacent two beam signals (step S3) to subtract each other and produce to seek to estimation (DOA) angle (step S4), estimating the angle that sends into FBFN beam position error correction processing unit proposed by the invention and carries out the calculating of angle correction, again angle correction is sent into the beam forming circuit at last and produced the 5th wave beam, aim at HUB with its main beam and carry out communication (step S5).Wherein LMDS systems array antenna is two-dimensional planar array antenna (2 take advantage of 6 antenna elements), can carry out angle modification to level and vertical beam position error.Planar array antenna disposes as shown in Figure 3, and its integrated antenna points to field pattern and is:

$\mathrm{AF}=\underset{n=1}{\overset{N}{\mathrm{\Σ}}}\left[\underset{m=1}{\overset{M}{\mathrm{\Σ}}}{J}_m{e}^{j(m-1)({\mathrm{kd}}_x\sin \mathrm{\θ}\cos \mathrm{\φ}+{\mathrm{\β}}_x)}\right]e^{j(n-1)({\mathrm{kd}}_y\sin \mathrm{\θ}\cos \mathrm{\φ}+{\mathrm{\β}}_y)}---\left(1\right)$

β _x＝-kd _xsinθ ₀cosφ ₀ (2)

β _y＝-kd _ysinθ ₀sinφ ₀ (3)

Chebyshev weights I in the formula _m=[0.54 0.78 1 10.78 0.54]

The number M=6 of horizontal antenna unit

The number N=2 of vertical antenna unit

The spacing d of horizontal antenna unit _x=λ/2

The spacing d of vertical antenna unit _y=λ/2, λ=wavelength

By adjusting (the θ in (2) and (3) formula ₀, φ ₀) main beam (main beam) can be aimed at (θ ₀, φ ₀), to reach tridimensional beam position control (beam steering) function.

In order to reach tridimensional beam position, at xz plane (θ _Azimuth) use multi-beam shaping circuit 3 to form five multi-beams, wherein wave beam 1 to wave beam 4 be responsible for seeking to, wave beam 5 is responsible for correct the sensing, at yz plane (θ _Elevation) use multi-beam shaping circuit 3 to form three multi-beams, wherein wave beam 1 and wave beam 2 be responsible for seeking to, the 3rd wave beam is responsible for correct the sensing, multi-beam (wave beam 1～wave beam 4) field pattern that the xz plane produces is shown in Fig. 4 (a), its corresponding adjacent beams difference field pattern is shown in Fig. 4 (b), and angle slope (angular slope) is respectively 1.43,1.75,1.43 decibels/degree (dB/degree).Multi-beam (wave beam 1 and the wave beam 2) field pattern that the yz plane produces is shown in Fig. 5 (a), and its corresponding adjacent beams difference field pattern is shown in Fig. 5 (b), and the angle slope is 0.217 a decibel/degree.DOA seeks to estimation and can remove the difference power of adjacent two wave beam received signals and obtain with the angle slope.

Beam forming circuit 3 is made up of power divider (power divider) 31 (not shown) and phase-shifter (phase shifter) 32 (figure does not show), in order to produce the multibeam signals of fixed directional, supplies the progressive echo signal in back to seek to (DOA) and estimates.Adjacent two wave beams of multi-beam planar array antenna produce difference field pattern (difference signalpattern) with amplitude comparison method to carry out signal source and seeks to (DOA) and estimating.Correspond to the value of poor field pattern by the received signal power difference of each wave beam, can parse the direction of signal source.

The automatic correcting process device 1 of beam position error is designed the filter (one step forward prediction filter) 11 (figure does not show) with stage prediction with the fuzzy rule of FBFN, causes the angle of beam position mistake because of the high wind random perturbation in order to compensation.In order to improve the random wave bundle error in pointing that the LMDS array antenna system causes because of high wind, the present invention has adopted FBFN beam position error correction processing unit, can make preferable beam position error correction at the distribution scenario of each moment beam position error.FBFN beam position error correction processing unit 1 as shown in Figure 6,13 regression functions of ground floor are the standard Gaussian function, are the Lei Shi mode parameter σ of the Taiwan wind distribution delivered according to National Central University's Civil Engineering Laboratory Mr. Huang Wenli for example ²And set, as shown in table 1.

Table 1

Pu good fortune wind scale	Gaussian Profile mean value E{r} (degree)	Gaussian Profile variance Var{r 2}(degree)	Lei Shi distributed constant σ 2
				4	1.8	0.86	2
5	2.5	1.7	4
				6	3.5	3.4	8
7	4.3	6.9	16
				8	6.1	10.3	24

Because the main cause that causes the beam position error is because wind-force causes the skew of antenna body structure, hypothesis is below moderate breeze during simulated experiment of the present invention, and the structural rigidity of antenna is enough to keep wave beam and correctly points to.Suppose that antenna pointing error in moderate breeze is distributed as that mean value is 1.8, variance is 0.86 Gaussian Profile, enhancing along with wind-force, blast with moderate breeze is reference, variance and mean value under linear other grade of increase wind-force are drawn up the regression function of FBFN and the weights that each is regular according to these data again.The beam position error mode that is caused by high wind is a Gaussian Profile, and its mean value is

$E\left[r\right]=\mathrm{\σ}\·\sqrt{\frac{\mathrm{\π}}{2}}---\left(4\right)$

Variance is

$\mathrm{Var}\left[r\right]=(2-\frac{\mathrm{\π}}{2}){\mathrm{\σ}}^2---\left(5\right)$

Standard Gauss's regression function

Input vector $\stackrel{-}{X}=\stackrel{-}{A}=[A[n\left]A\right[n-1]...A[n-10]]$

Be the Gaussian function center vector, on behalf of meaning, each parameter of vector that includes 11 sampling values be:

A (n)～A (n-10): the n～n-10 beam position error angle value constantly

 ₁～ ₁₃: according to the set input regression function of antenna deviation profile

μ ₁～μ ₁₃: the triggering intensity of each rule

μ ₁～μ ₁₃: normalized triggering intensity

${\stackrel{-}{\mathrm{\μ}}}_i=\frac{{\mathrm{\μ}}_i}{\underset{i}{\mathrm{\Σ}}{\mathrm{\μ}}_i}---\left(8\right)$

f ₁～f ₁₃: the consequent output weights that each rule is corresponding

The output compensation rate $Y\left(n\right)={\stackrel{-}{\mathrm{\μ}}}_i{f}_i---\left(9\right)$

Consider that in the present invention the beam position error that wind-force causes has the distribution of negative mean value, and may produce less wind-force disturbance under the actual state.Trend with reference to five kinds of wind distribution has designed 13 standard Gauss regression functions and consequent output weights.Its parameter setting is as follows:

${\stackrel{-}{c}}_1={{[-6.14]}_{1\×11}}^T$ f ₁＝-6.14

${\stackrel{-}{c}}_2={{[-5]}_{1\×11}}^T$ f ₂＝-5

${\stackrel{-}{c}}_3={{[-3.5]}_{1\×11}}^T$ f ₃＝-3.5

${\stackrel{-}{c}}_4={{[-2.5]}_{1\×11}}^T$ f ₄＝-2.5

${\stackrel{-}{c}}_5={{[-1.7]}_{1\×11}}^T$ f ₅＝-1.7

${\stackrel{-}{c}}_6={{[-0.5]}_{1\×11}}^T$ f ₆＝-0.5

${\stackrel{-}{c}}_7={{\left[0\right]}_{1\×11}}^T$ f ₇＝0

${\stackrel{-}{c}}_8={{[0.5]}_{1\×11}}^T$ f ₈＝0.5

${\stackrel{-}{c}}_9={{[1.7]}_{1\×11}}^T$ f ₉＝1.7

${\stackrel{-}{c}}_{10}={{[2.5]}_{1\×11}}^T$ f ₁₀＝2.5

${\stackrel{-}{c}}_{11}={{[3.5]}_{1\×11}}^T$ f ₁₁＝3.5

${\stackrel{-}{c}}_{12}={{\left[5\right]}_{1\×11}}^T$ f ₁₂＝5

${\stackrel{-}{c}}_{13}={{\left[6.14\right]}_{1\×11}}^T$ f ₁₃＝6.14

σ _i＝2，i＝1～13

Preferred embodiment

Produce five kinds of Gausses' (Gaussian) beam position error angular distribution during fuzzy the experiment, send in the beam position error correction processing unit and carry out the beam position angle modification.By five kinds of Gaussian beam error in pointing angular distribution of five kinds of wind distribution correspondences, its mean value (m) and amount of variability (σ ²) be respectively (m, σ ²)=(1.8,0.86), (2.5,1.7), (3.5,3.4), (4.3,6.9), (6.1,10.3), be referred to as first type～the 5th type Gaussian Profile.Respectively 400 data input FBFN circuit and recursive least-squares method (RLS) 11 stage filter are done 500 Mondicaros (Monte-Carlo) experiment, simulated experiment result such as Fig. 7～shown in Figure 11.

The meaning of four learning curve (learning curve) representative is as follows among the figure:

Do not revise (No correction) curve: the mean square deviation (ensemble-averaged square error) that expression wind-force causes

Direct compensation (direct compensation) curve: the mean square deviation that is directly produced with the compensation of DOA estimated value is used in expression

The RLS curve: the mean square deviation after the compensation of RLS predictive filter is used in representative

The FBFN curve: the mean square deviation after the fuzzy rule correcting process of FBFN is used in representative

FBFN beam position error correction processing unit and recursive least-squares (RLS) adaptive filter are relatively, experimental result shows uses the RIS adaptive filter mean square deviation on 11 rank to approach steady-state value between number of repetition (number of iterations) n=60～80, and (mean square deviation is up to 10 but the transient response meeting of RLS is very big ¹～10 ³) easily cause LMDS system communication quality to reduce.FBFN beam position error correction processing unit has preferable transient response value, and (mean square deviation is about 1～10 ²), preferable convergence rate (n=10～20) and lower beam position error correction convergency value.By analog result show that FBFN beam position error correction processing unit can satisfy that transient response is little, fast convergence rate and the low application demand of beam position convergence error value, the present invention can change the communication quality of LMDS system really.

Claims (4)

1. one kind is used for LMDS array antenna beam pointing error FBFN modification method, comprises the following step:

-receive the base station signal at this LMDS user side with multiple-beam array antenna;

-make this base station signal produce the different beam signal of a plurality of intensity of fixed directional in the horizontal direction via a beam forming circuit;

-from the different beam signal of these a plurality of intensity, select the strongest adjacent two beam signals and subtract each other with produce one seek to the estimation angle signal;

-transmit this to seek to estimation angle signal to FBFN beam position error correction processing unit with the calculating of fuzzy basis function network mode execution angle correction;

-the angle correction that transmits this calculating produces another wave beam to this beam forming circuit, carries out communication with the main beam alignment base platform of this another wave beam.

2. the method for claim 1, wherein this multiple-beam array antenna is the two-dimensional planar array antenna.

3. one kind is used for LMDS array antenna beam pointing error FBFN correcting device, comprises:

One multiple-beam array antenna is installed in this LMDS user side, in order to receive the base station signal;

One beam forming circuit contains power divider and phase-shifter, uses so that this base station signal produces the different beam signal of a plurality of intensity of fixed directional in a horizontal direction;

One seeks to estimating apparatus, in order to select the strongest adjacent two beam signals and subtract each other to produce one and seek to the estimation angle signal from the different beam signal of these a plurality of intensity; An and FBFN beam position error correction processing unit, receiving this seeks to the estimation angle signal and with the calculating of fuzzy basis function network mode execution angle correction, and the angle correction of this calculating of transmission is to this beam forming circuit, make this beam forming circuit produce another main beam, main beam alignment base platform carries out communication thus.

4. device as claimed in claim 3, wherein this multiple-beam array antenna is the two-dimensional planar array antenna.

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