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

Abstract

A system capable of achieving improvement of satellite link performance by using an intelligent antenna comprises an antenna array, an analog/digital (A/D) conversion module, a digital/analog (D/A) conversion module and a pre-processing module. The antenna array adopts an antenna array method to receive satellite signals and transmits analog signals output by the D/A conversion module after the signals are synthesized through antenna array beams. The A/D conversion module converts satellite analog signals received by the antenna array into digital signals during downlink and transmits the converted digital signals to the pre-processing module. The D/A conversion module converts the processed digital signals into the analog signals during uplink and sends the analog signals to the antenna array to be transmitted. The pre-processing module conducts beam searching on received system broadcast signals during cell searching, determines cell identity (ID), and system broadcast information comprises beam number information. When a satellite communication link is built, corresponding array element weighting coefficient is determined according to the cell ID, and the received digital signals and the array element weighting coefficient are transmitted to a beam-forming network. The beam-forming network initially adjusts antenna pointing to align to a satellite according to the received digital signals and the array element weighting coefficient, and precise adjusting of the antenna pointing is achieved.

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. applying intelligent antenna is realized the system that satellite link performance strengthens, and it is characterized in that: comprise 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; When up, convert the digital signal after processing to analog signal, give 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; Pretreatment module detects the system broadcasts signal receiving, and after deadline and Frequency Synchronization, extracts the wave beam information in broadcast message, and this wave beam number is community ID; Pretreatment module is according to community ID, and corresponding weighting coefficient values in lookup table, by this weighting coefficient values input beam-forming network, completes antenna by beam-forming network and tentatively point to adjustment.

2. a kind of applying intelligent antenna according to claim 1 is realized the system that satellite link performance strengthens, and it is characterized in that described beam-forming network carries out accurate adjustment process to antenna direction 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.

3. a kind of applying intelligent antenna according to claim 1 is realized the system that satellite link performance strengthens, and it is characterized in that described beam-forming network carries out accurate adjustment process to antenna direction 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.