CN102510304B - System capable of achieving improvement of satellite link performance by using intelligent antenna - Google Patents

Abstract

A system that uses a smart antenna to enhance the performance of a satellite link. The antenna array uses an antenna array to receive satellite signals, and transmits the analog signal output by the D/A conversion module through antenna array beam synthesis; the A/D conversion module, Convert the satellite analog signal received by the antenna array into a digital signal during downlink, and send the converted digital signal to the preprocessing module; the D/A conversion module converts the processed digital signal into an analog signal during uplink, and sends it to the antenna Array transmission; the preprocessing module, when searching for a cell, performs a beam search on the received system broadcast signal to determine the cell ID, and the system broadcast information contains beam number information; when establishing a satellite communication link, determine the corresponding cell ID according to the cell ID The array element weighting coefficient transmits the received digital signal and the array element weighting coefficient to the beamforming network; the beamforming network initially adjusts the antenna pointing to the satellite according to the received digital signal and the array element weighting coefficient, and realizes the precise adjustment of the antenna pointing .

Description

A kind of applying intelligent antenna is realized the system that satellite link performance strengthens

Technical field

The present invention relates to a kind of applying intelligent antenna and realize the system that satellite link performance strengthens, belong to satellite communication field.

Background technology

Satellite communication system is all limited systems of a power and frequency, in order to strengthen satellite link performance, improve power system capacity, forward link generally adopts increase satellite transmitting antenna bore to increase antenna gain, or reach by increasing satellite launch power the object that link strengthens, return link generally adopts increase user's terminal transmitting power to promote link performance, but do so not only and bring pressure to the satellite system of power limited, also affected the Miniaturization Design of user terminal, the increase of power has also brought the harm of electric electromagnetic radiation, suppressed the popularization of satellite communication applications.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, provide a kind of applying intelligent antenna to realize the system that satellite link performance strengthens, this system, for the satellite communication system of power limited, can be improved system link performance and expand power system capacity.

Technical solution of the present invention is: a kind of applying intelligent antenna is realized the system that satellite link performance strengthens, and comprises aerial array, A/D conversion module, D/A conversion module, pretreatment module and beam-forming network;

Aerial array, adopts aerial array mode receiving satellite signal, after the analog signal of D/A conversion module output is synthesized by antenna array beam, launches;

A/D conversion module, Satellite Simulation signal when descending, aerial array being received converts digital signal to, and the digital signal after conversion is sent to pretreatment module; D/A conversion module, converts the digital signal after processing to analog signal when up, gives aerial array transmitting;

Pretreatment module, when Cell searching, carries out wave beam search to the system broadcasts signal receiving, and determines community ID, contains wave beam information in this system broadcast information; When setting up satellite communication link, according to community ID, determine corresponding array element weight coefficient, the digital signal of reception and array element weight coefficient are transferred to beam-forming network;

Beam-forming network is tentatively adjusted antenna direction to satelloid according to the digital signal and the array element weight coefficient that receive, and realizes the accurate adjustment to antenna direction.

Described pretreatment module need to be solidified a form before determining community ID in system, this form is comprised of with corresponding array element weight coefficient wave beam number, array element weight coefficient is to point to and determine according to the relative satellite in satellite respective beam coverage cell, and described wave beam is number corresponding one by one with community ID.

Described definite community ID also completes antenna tentatively to point to the step of adjustment as follows:

(3.1) detect the system broadcasts signal receiving, after deadline and Frequency Synchronization, extract the wave beam information in broadcast message, this wave beam number is community ID;

(3.2), according to community ID, corresponding weighting coefficient values in lookup table, by this weighting coefficient values input beam-forming network, completes antenna by beam-forming network and tentatively points to adjustment.

It is described that antenna direction is carried out to accurate adjustment process is as follows:

The preliminary antenna direction of adjusting is to after satelloid, system wireless network is controlled RNC according to curing in advance accurate adjustment form, from form, obtain all array element weight coefficients within the scope of the beamwidth that preliminary aligning points to, successively array element weight coefficient is passed to beam-forming network, beam-forming network is adjusted antenna direction according to the array element weight coefficient receiving, and antenna is passed the satellite-signal intensity now receiving back system wireless network and controlled RNC simultaneously; System wireless network is controlled all satellite-signal intensity that RNC judgement receives, and when satellite-signal intensity is the strongest, corresponding array element weight coefficient is transferred to beam-forming network, by beam-forming network, realizes the antenna direction accurate adjustment that this array element weight coefficient is corresponding; Above-mentioned accurate adjustment form is the position of same wave beam inside and the corresponding form of corresponding array element weight coefficient.

It is described that antenna direction is carried out to accurate adjustment process is as follows:

The preliminary antenna direction of adjusting is to after satelloid, beam selection pretreatment module is according to curing in advance accurate adjustment form, from form, obtain all array element weight coefficients within the scope of the beamwidth that preliminary aligning points to, successively array element weight coefficient is passed to beam-forming network, beam-forming network is adjusted antenna direction according to the array element weight coefficient receiving; Beam selection pretreatment module receives the satellite-signal that this antenna direction is corresponding and calculates signal strength signal intensity, all satellite-signal intensity that judgement receives, when satellite-signal intensity is the strongest, corresponding array element weight coefficient is transferred to beam-forming network, by beam-forming network, realizes the antenna direction accurate adjustment that this array element weight coefficient is corresponding; Above-mentioned accurate adjustment form is the position of same wave beam inside and the corresponding form of corresponding array element weight coefficient.

The present invention compared with prior art beneficial effect is:

(1) system of the present invention, when return link transmits, to satelloid, makes terminal transmit power more concentrated by synthetic directional beam, has improved antenna gain and the back access capability of user terminal.

(2) when system forward link of the present invention receives downstream signal, by array antenna received signals, can obtain gain, improve forward link receptivity, under equal satellite launch power condition, increase power system capacity.

(3) the present invention is also for the special applications scene of satellite mobile communication, a kind of new system cell search procedure and communication link process of establishing are proposed, when having improved band efficiency, simplified flow process, accelerated the process that Cell searching and communication link are set up.

The present invention is particularly suitable for the satellite communication field of power and frequency limited.

Accompanying drawing explanation

Fig. 1 is system schematic of the present invention;

Fig. 2 is instance system schematic diagram in embodiment of the present invention;

Fig. 3 is instance system aerial array schematic diagram in embodiment of the present invention;

Fig. 4 is instance system user wave beam coverage diagram in embodiment of the present invention;

Fig. 5 is that in embodiment of the present invention, schematic diagram is divided in the interior community of instance system user wave beam.

Embodiment

Below in conjunction with accompanying drawing, introduce in detail the present invention.

As shown in Figure 1, a kind of applying intelligent antenna is realized the system that satellite link performance strengthens, and comprises aerial array, A/D conversion module, D/A conversion module, pretreatment module, beam-forming network.After completing antenna and accurately point to, the present invention completed the Base-Band Processing process of satellite-signal by digital signal processing module.

Aerial array, adopts aerial array mode receiving satellite signal, after the analog signal of D/A conversion module output is synthesized by antenna array beam, launches; Bay number can suitably be chosen according to the actual requirements, and array shape also can be divided into linear array, face battle array etc. according to the geometrical relationship between array element; A/D conversion module, Satellite Simulation signal when descending, aerial array being received converts the digital signal of being convenient to digital processing to, and the digital signal after conversion is sent to pretreatment module; D/A conversion module, converts the digital signal after processing to analog signal when up, gives aerial array transmitting; Above-mentioned aerial array and A/D conversion module, D/A conversion module and signal processing module are techniques well known, do not repeat herein.

(1) pretreatment module

Pretreatment module, when Cell searching, carries out wave beam search to the digital signal receiving, and determines community ID; When setting up satellite communication link, according to community ID, determine array element weight coefficient, the digital signal of reception and array element weight coefficient are transferred to beam-forming network;

Pretreatment module need to be solidified a form before determining community ID in system, this form is comprised of with corresponding array element weight coefficient wave beam number, array element weight coefficient is to point to and determine according to the relative satellite in satellite respective beam coverage cell, and described wave beam is number corresponding one by one with community ID.

For example, as shown in Figure 4, in this example, antenna array adopts 4 aerial arrays (its system schematic is as shown in Figure 2) to satellite user wave beam coverage diagram, and antenna parameter arranges as follows:

4 slave antennas are arranged in separately as 00 of Fig. 3,01,10 and 11 positions; D in Fig. 3 _xfor x direction unit interval, d _yfor y direction unit interval; for controlling antenna wave beam to point, θ is the angle of pitch, for azimuth, (m, n) represents array element number, and (m, n) is (0,0), (0,1), (1,0) and (1,1).

$d_x=d_y=\frac{\mathrm{\λ}}{2},$ λ is operation wavelength.

Antenna current Amplitude Ratio is 1: 1: 1: 1;

Antenna initial phase difference is 0;

Antenna gain is normalized to 1;

The Table Design corresponding with this coverage diagram is as follows:

Form is the two-dimentional form consisting of wave beam number and array element weight coefficient, wave beam number for as shown in Figure 41,2,3...37, array element weight coefficient is tried to achieve by following formula (1), (2) and (3):

${\mathrm{\θ}}_N={\tan }^{-1}\left(\frac{\cos ({\mathrm{\α}}_N-{\mathrm{\α}}_s)\cos {\mathrm{\β}}_N-0.15}{\sqrt{1-{\left(\cos ({\mathrm{\α}}_N-{\mathrm{\α}}_s)\cos {\mathrm{\β}}_N\right)}^2}}\right)---\left(1\right)$

Wherein, (α _s, 0) and be Satellite Orbit Determination position, α _sfor orbital longitude; N beam center position is (α _n, β _n), α wherein _nfor N beam center longitude, β _nfor N beam center latitude; θ _nfor the angle of pitch of controlling antenna wave beam to point, the azimuth of controlling antenna wave beam to point, be the weighted value vector of N wave beam, $w_{\mathrm{nm}}^N=\left[\begin{array}{cccc}{w}_{00}^N& w_{01}^N& w_{10}^N& w_{11}^N\end{array}\right],$ N＝1、2、3.....37。

Form is $\left[\begin{array}{cccc}{w}_{00}^1& w_{01}^1& w_{10}^1& w_{11}^1\\ w_{00}^2& w_{01}^2& w_{10}^2& w_{11}^2\\ .& & & \\ .& & & \\ .& & & \\ w_{00}^{37}& w_{01}^{37}& w_{10}^{37}& w_{11}^{37}\end{array}\right]$

The step of determining community ID is as follows:

(3.1) detect the system broadcasts signal receiving, after deadline and Frequency Synchronization, extract the wave beam information in broadcast message, this wave beam number is community ID;

(3.2), according to community ID, corresponding weighting coefficient values in lookup table, by this weighting coefficient values input beam-forming network, completes antenna by beam-forming network and tentatively points to adjustment.

(2) beam-forming network

Beam-forming network is tentatively adjusted antenna direction to satelloid according to array element weight coefficient, and realizes antenna direction is carried out to accurate adjustment.

Describedly antenna direction carried out to accurate adjustment there are two kinds of implementations:

Mode (1): tentatively adjust antenna direction to after satelloid, system wireless network is controlled RNC according to curing in advance accurate adjustment form, from form, obtain all array element weight coefficients within the scope of the beamwidth that preliminary aligning points to, successively array element weight coefficient is passed to beam-forming network, beam-forming network is adjusted antenna direction according to the array element weight coefficient receiving, and antenna is passed the satellite-signal intensity now receiving back system wireless network and controlled RNC simultaneously; System wireless network is controlled all satellite-signal intensity that RNC judgement receives, and when satellite-signal intensity is the strongest, corresponding array element weight coefficient is transferred to beam-forming network, by beam-forming network, realizes the antenna direction accurate adjustment that this array element weight coefficient is corresponding; Above-mentioned accurate adjustment form is the position of same wave beam inside and the corresponding form of corresponding array element weight coefficient.

Mode (2): tentatively adjust antenna direction to after satelloid, beam selection pretreatment module is according to curing in advance accurate adjustment form, from form, obtain all array element weight coefficients within the scope of the beamwidth that preliminary aligning points to, successively array element weight coefficient is passed to beam-forming network, beam-forming network is adjusted antenna direction according to the array element weight coefficient receiving; Beam selection pretreatment module receives the satellite-signal that this antenna direction is corresponding and calculates signal strength signal intensity, all satellite-signal intensity that judgement receives, when satellite-signal intensity is the strongest, corresponding array element weight coefficient is transferred to beam-forming network, by beam-forming network, realizes the antenna direction accurate adjustment that this array element weight coefficient is corresponding; Above-mentioned accurate adjustment form is the position of same wave beam inside and the corresponding form of corresponding array element weight coefficient.

This form producing principle is a form as above, and just this form is divided for the community of concrete certain wave beam inside, and community is divided more intensive, and antenna-point accuracy adjustment is more accurate.Supposing the system user is positioned at wave beam No. 1, and by No. 1 wave beam, according to carrying out as shown in Figure 54 equal portions divisions, 1,2,3,4 represent to divide respectively the center of rear community, hypothesis be the M district weighted value vector of No. 1 wave beam, $w_{\mathrm{nm}}^M=\left[\begin{array}{cccc}{w}_{00}^M& w_{01}^M& w_{10}^M& w_{11}^M\end{array}\right],$ M=1,2,3,4, wherein calculating, according to formula (1), (2), (3), is (α now _m, β _m) represent the longitude and latitude of the M district center of No. 1 wave beam, form is

$\left[\begin{array}{cccc}{w}_{00}^1& w_{01}^1& w_{10}^1& w_{11}^1\\ w_{00}^2& w_{01}^2& w_{10}^2& w_{11}^2\\ w_{00}^3& w_{00}^3& w_{00}^3& w_{00}^3\\ w_{00}^4& w_{01}^4& w_{10}^4& w_{11}^4\end{array}\right]$

The unspecified part of the present invention belongs to general knowledge as well known to those skilled in the art.

Claims (3)

1. An application smart antenna realizes a system for satellite link performance enhancement, characterized in that: comprising an antenna array, an A/D conversion module, a D/A conversion module, a preprocessing module and a beam forming network; The antenna array is used to receive satellite signals in the form of an antenna array, and transmit the analog signal output by the D/A conversion module through antenna array beam synthesis; The A/D conversion module converts the satellite analog signal received by the antenna array into a digital signal during downlink, and sends the converted digital signal to the preprocessing module; during uplink, converts the processed digital signal into an analog signal and sends it to Antenna array transmission; The preprocessing module performs beam search on the received system broadcast signal during cell search to determine the cell ID, and the system broadcast information contains beam number information; when establishing a satellite communication link, determines the corresponding array element weighting according to the cell ID Coefficients, transmit the received digital signals and array element weighting coefficients to the beamforming network; The beamforming network initially adjusts the antenna pointing to the satellite according to the received digital signal and the weighting coefficient of the array element, and realizes the precise adjustment of the antenna pointing; Before the preprocessing module determines the cell ID, a table needs to be solidified in the system. The table is composed of beam numbers and corresponding array element weighting coefficients. The array element weighting coefficients are determined according to the relative satellite pointing of the corresponding beam coverage cell of the satellite. The described The beam number is in one-to-one correspondence with the cell ID; the preprocessing module detects the received system broadcast signal, and after completing the time and frequency synchronization, extracts the beam number information in the broadcast information, and the beam number is the cell ID; the preprocessing module, according to the cell ID, Look up the corresponding weighting coefficient value in the table, and input the weighting coefficient value into the beamforming network, and the beamforming network will complete the initial pointing adjustment of the antenna. 2. A kind of application smart antenna according to claim 1 realizes the system of satellite link performance enhancement, it is characterized in that described beamforming network carries out precise adjustment process to antenna pointing as follows: After the initial adjustment of the antenna pointing to the satellite, the system wireless network control RNC obtains all the weighting coefficients of the array elements within a beam width range of the initial alignment pointing from the table according to the pre-solidified precise adjustment table, and sequentially transmits the weighting coefficients of the array elements to For the beamforming network, the beamforming network adjusts the antenna pointing according to the received array element weighting coefficient, and at the same time, the antenna sends the received satellite signal strength back to the system wireless network control RNC; the system wireless network control RNC judges the strength of all satellite signals received, The weighting coefficient of the array element corresponding to the strongest satellite signal strength is transmitted to the beamforming network, and the beamforming network realizes the precise adjustment of the antenna pointing corresponding to the weighting coefficient of the array element; the above precise adjustment table is the position inside the same beam and the corresponding array element Corresponding table of weighting coefficients. 3. A kind of application smart antenna according to claim 1 realizes the system of satellite link performance enhancement, it is characterized in that described beam forming network carries out precise adjustment process to antenna pointing as follows: After the initial adjustment of the antenna pointing to the satellite, the beam selection preprocessing module obtains the weighting coefficients of all array elements within a beam width range of the preliminary alignment pointing from the table according to the pre-solidified precise adjustment table, and sequentially transmits the weighting coefficients of the array elements to For the beamforming network, the beamforming network adjusts the antenna pointing according to the received array element weighting coefficient; the beam selection preprocessing module receives the satellite signal corresponding to the antenna pointing and calculates the signal strength, judges the signal strength of all received satellites, and maximizes the satellite signal strength When it is strong, the corresponding array element weighting coefficient is transmitted to the beamforming network, and the beamforming network realizes the precise adjustment of the antenna pointing corresponding to the array element weighting coefficient; the above-mentioned precise adjustment table is the correspondence table between the position inside the same beam and the corresponding array element weighting coefficient .