CN104125002A - Rapid satellite locking method of portable satellite receiver - Google Patents

Abstract

The invention discloses a rapid satellite locking method of a portable satellite receiver. Coarse tuning contains the following steps: position of the receiver is determined; a satellite which is expected to be locked is selected; pitch angle, azimuth angle and polarization angle of the satellite relative to the receiver are calculated; and angle of the receiver is adjusted manually. Fine tuning contains the following steps: a downlink beacon signal of the satellite is received and satellite signal power within adjustable bandwidth is calculated; signal maximum power point is obtained; pitch angle and azimuth angle of the receiver are finely-tuned so as to be directed at the maximum power point; and polarization angle is finely-tuned and the maximum power point is observed, and the polarization angle which maximizes power is selected. An interface of a visualized terminal displays signal intensity within bandwidth during the fine-tuning process at real time and visually shows whether the result of the fine-tuning operation is accurate. The fine-tuning operation is convenient and fast. The downlink beacon signal of the satellite is received so as to realize measurement of the signal intensity. It is not necessary to transmit signals by antennas. The influence of adjacent satellite interference can be avoided effectively. Accuracy of satellite signal intensity measurement is higher.

Description

A kind of method of portable satellite receiver quick lock in satellite

Technical field

The present invention relates to technical field of satellite communication, particularly relate to a kind of method of portable satellite receiver quick lock in satellite.

Background technology

Mobility, wide area complex network that satellite communication has three-dimensional seamless coverage ability, unique universal service ability, overlay area flexibly form ability, the mutual concatenation ability of wide area Internet, and distinctive wide area broadcast and multicast ability, go for multiple business, obtained application more and more widely in military communication, mobile communication, emergency communication and field of broadcast televisions.

Up to now, occur that the ground satellite station of multiple business ability, multiple price is meeting different scene application demands, as vehicle satellite communication in motion is applied to vehicular platform conventionally, and price is comparatively expensive, but limitation is that the place that can not arrive at some automobile cannot be used.Portable satellite receiver is exactly a kind of restriction of any carrier, satellite communication terminal with low cost of not being subject to.In use, staff carries or bears portable satellite receiver and arrives and use on-the-spotly, launches the antenna of receiver, can set up and being connected of command centre after locking satellite (to star).

But the method for traditional portable satellite receiver locking satellite is mostly only accomplished to coarse adjustment and just finishes star to operate, the accuracy of locking satellite signal is lower, and the communication reliability of satellite communication system is poor.In addition, because the intrinsic reason of conventional portable receiver makes the infinitely refinement of sign of pitching, orientation, polarizing angle, conventionally can only degree of being accurate to (°), this levels of precision to manual direct control has caused certain obstruction.

As ZL200410064896.6, portable satellite receiver is searched star method and apparatus fast, according to receiving ground latitude and receiving constellation, by preset reception antenna reflecting surface orientation and the luffing angle of manually tabling look-up, by centered by preset orientation ± 90 ° of spatial domains are divided into some fields of search, range searching one by one, until signal maximum locking orientation and pitching.This tradition is searched star method and apparatus and is had following problem: (1) utilizes mechanization to design the helical scanning of feasible region, spatial domain, and structure is comparatively complicated, and design cost is higher; (2) by preset reception antenna reflecting surface orientation and the luffing angle of manually tabling look-up, labor workload is larger, and intelligent degree is low, and angle calculation accuracy is not high enough; (3) in the process of locking satellite, only consider the angle of pitch and azimuth, do not consider the polarizing angle of receiver antenna, the oscillator that cannot ensure to polarize is adjusted to the direction consistent with electromagnetic wave, easily occurs polarization interference, directly affect star accuracy, thereby affect satellite signal receiving effect.

And for example ZL201210286953.X, Portable narrow band satellite communication equipment and control method thereof, the local information of extracting according to GPS module, calculates azimuth and the angle of pitch of local position with respect to certain communication satellite; Carry out coarse adjustment to star according to azimuth, the angle of pitch and polarizing angle; Beacon receiver uses the first bandwidth to judge signal strength values, according to signal strength values fine tuning azimuth, the angle of pitch and polarizing angle, until signal strength values maximum.There is following problem to star method in this: (1), in the measuring process of satellite-signal intensity, this need to use two bandwidth to star method, has the restriction of amount of bandwidth; (2) in the measuring process of satellite-signal intensity: first send a radiofrequency signal by antenna, and then reception forwards the radiofrequency signal of getting off through satellite.Because receiver antenna when the signal strength measurement has only completed coarse adjustment, not completely to satelloid, therefore when to satellite emission signal, can face star and disturb because angular deviation causes, directly affect the measuring accuracy of satellite-signal intensity.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art, a kind of method to the high portable satellite receiver quick lock in satellite of star accuracy is provided, according to parameter and the autonomous computer azimuth angle of receiver local position, the angle of pitch and the polarizing angle of wanting locking signal satellite, high, the intelligent degree of counting accuracy is high, easy to use; The interface of visual terminal shows the signal strength signal intensity in bandwidth in trim process always, shows that intuitively whether the result of fine setting operation is accurate, finely tunes easy to operate and speed is fast; Consider azimuth, the angle of pitch and polarizing angle, adjust the polarizing angle oscillator that makes to polarize and adjust to the direction consistent with electromagnetic wave, the signal strength signal intensity maximum of oscillator induction, can avoid occurring that polarization disturbs, and makes reception the best, higher to star accuracy; First detect the signal strength signal intensity of current reception, obtain progressive minimizing bandwidth after maximum point, there is no the restriction of amount of bandwidth, make user see more clearly; Receive the descending beacon signal of satellite to realize the measurement of signal strength signal intensity, without by antenna transmission signal, can effectively avoid facing the impact that star disturbs, make the measuring accuracy of satellite-signal intensity higher.

The object of the invention is to be achieved through the following technical solutions: a kind of method of portable satellite receiver quick lock in satellite, it comprises a coarse steps and a trim step:

Described coarse steps comprises following sub-step:

S101: utilize positioner to determine position and the orientation of portable satellite receiver;

S102: the satellite of selecting wish locking;

S103: according to the positional information of satellite and portable satellite receiver, calculate the angle of pitch, azimuth and the polarizing angle information of this satellite with respect to portable satellite receiver by portable satellite receiver;

S104: manually adjust the angle of portable satellite receiver according to each angle information, make the satellite of its rough alignment wish locking, complete coarse adjustment;

Described trim step comprises following sub-step:

S201: on coarse adjustment basis, receive the descending beacon signal of satellite and carry out the satellite-signal power calculation in certain BREATHABLE BANDWIDTH;

S202: the maximum power point that draws satellite-signal;

S203: finely tune the angle of pitch and the azimuth of portable satellite receiver under the power instruction of visual terminal, make it to aim at this maximum power point;

It should be noted that, the interface of the visual terminal of portable satellite receiver shows the signal strength signal intensity in bandwidth in trim process always, whether the result of demonstration fine setting operation directly perceived is accurate: if find in azimuth or angle of pitch adjustment process, the intensity of beacon frequency declines, anisotropy is adjusted in explanation, needs back adjustment; If intensity improves, direction is correct, continues to adjust to this direction; After intensity is raised to certain maximum, start to decline, this maximum is optimum orientation, and azimuth and the angle of pitch are fixed on to this direction.

S204: fine setting polarizing angle is also observed the maximum power point of visual terminal, makes prominent polarizing angle in selected trim process, completes fine setting.

Same, the interface of the visual terminal of portable satellite receiver shows the signal strength signal intensity in bandwidth in trim process always, whether the result of demonstration fine setting operation directly perceived is accurate: if find in polarizing angle adjustment process, the intensity of beacon frequency declines, anisotropy is adjusted in explanation, needs back adjustment; If intensity improves, direction is correct, continues to adjust to this direction; After intensity is raised to certain maximum, start to decline, this maximum is optimum orientation, and polarizing angle is fixed on to this direction.

Further, the positioner described in step S101 comprises GPS locator or electronic compass.

Further, the method for the satellite of the locking of the selection wish described in step S102 is: the satellite of being inputted and selected wish locking by the visual terminal interface of portable satellite receiver.

The computational process of the angle of pitch, azimuth and polarizing angle is as follows:

The connecting line of satellite receiver and fixed statellite is called demand line, demand line projection on the ground, and the camber line between satellite receiver and substar is called the rhumb line of satellite receiver to fixed statellite, and the definite plane of rhumb line and demand line is called azimuth plane.The Due South that azimuth refers to satellite receiver place warp is to the angle forming with azimuth plane in the direction of the clock, represents with ∠ MAN, and the angle of pitch refers to the rhumb line of satellite receiver and the angle of demand line.

Fig. 1 has provided the geometrical relationship between fixed statellite S and satellite receiver A.In figure, A represents satellite receiver, and S represents fixed statellite, and O represents earth the earth's core, B is the warp of satellite receiver A and the intersection point in equator, the intersection point C that the line of O and S is gone up is at the earth's surface called substar, and the camber line AC of ordering by A point and C on earth surface is called rhumb line, the tangent line that AN is AC, AM is the tangent line of AB, face OAS is azimuth, and D is the intersection point of tangent line AM and equatorial plane, and E is the intersection point of tangent line AN and equatorial plane.

If the longitude of satellite receiver A and latitude are respectively and θ ₁, fixed statellite longitude is , difference of longitude below specifically provide the required azimuth φ of satellite receiver antenna alignment satellite _a, angle of pitch φ _ewith polarizing angle φ _jformulation process.

Azimuthal computational process is as follows:

Can be obtained by Fig. 1:

AD＝ODsinθ ₁；

${\tan \mathrm{\φ}}_a=\frac{\mathrm{DE}}{\mathrm{AD}};$

The azimuth that can draw satellite receiver antenna by above three formulas:

Utilize azimuth that above formula obtains taking Due South to trying to achieve as benchmark, in accordance with regulations, azimuth is all taking direct north as benchmark, the azimuth on historical facts or anecdotes border, except need to converting according to the accuracy relation of antenna and satellite and position, also will be transformed into the coordinate system that direct north is benchmark.

The computational process of the angle of pitch is as follows:

For obtaining the angle of pitch, be the parallel lines SF of EA, the extended line of OA and SF intersect at a F, known in right-angled triangle AFS by parallel relation:

${\tan \mathrm{\φ}}_e=\tan {\mathrm{\φ}}_f=\frac{\mathrm{AF}}{\mathrm{FS}}=\frac{\mathrm{OF}-\mathrm{OA}}{\mathrm{FS}};$

Again:

OF＝OScosα＝(OC+CS)cosα；

FS＝OSsinα＝(OC+CS)sinα；

Therefore have:

${\tan \mathrm{\θ}}_e=\frac{(\mathrm{OC}+\mathrm{CS})\cos \mathrm{\α}-\mathrm{OA}}{(\mathrm{OC}+\mathrm{CS})\sin \mathrm{\α}}=\frac{(R+h)\cos \mathrm{\α}-R}{(R+h)\sin \mathrm{\α}}=\frac{{\cos \mathrm{\θ}}_1\cos \mathrm{\φ}-\frac{R}{R+h}}{\sin \mathrm{\α}};$

In above formula, OA and OC are the distance of satellite receiver apart from earth the earth's core, represent with R, get 6378 kilometers of earth mean radiuss; All geostationary satellites are all distributed in overhead, equator, and its height represents with h, gets 35860 kilometers, brings above formula into and obtains:

Therefore the angle of pitch:

The computational process of polarizing angle is as follows:

The electromagnetic wave of aerial radiation all polarizes, polarization of electromagnetic wave is to define according to electromagnetic wave direction of electric field intensity in communication process, if electromagnetic electric field intensity be projected in direction of propagation vertical plane on track be a straight line, be referred to as linear polarization; If electric field intensity projected footprint is circle or oval, be circular polarization or elliptical polarization, the polarization definition datum of satellite radiation polarization wave polarization and ground level reception antenna is different, and for a satellite receiving earth station, the polarization of its antenna defines taking ground level as benchmark.The electric wave of electric field intensity plane and earth surface is horizontal polarization, and the narrow limit of feed rectangular waveguide mouth is perpendicular to ground.

When the longitude of satellite receiver is when longitude equates in-orbit with satellite, the electric field component of polarized wave just in time parallel (or vertical) in the ground level of satellite receiver, now polarizing angle is zero.As long as satellite receiver and satellite be not on a longitude, just there is an angle in electric field and ground level in the polarized wave that satellite transmission comes, and this angle is called polarizing angle.For the reception having reached, adjust outside the azimuth and the angle of pitch of receiver antenna, also should adjust according to the numerical value of polarizing angle the direction of feed rectangular waveguide mouth, the oscillator that makes to polarize is adjusted to the direction consistent with electromagnetic wave, the now polarization coupling polarization next with satellite transmission completely, the signal strength signal intensity maximum of oscillator induction, reception the best.Its polarizing angle of the satellite receiver of diverse geographic location is also different, and the required theoretical polarizing angle of satellite receiver antenna alignment satellite is:

Further, described step S103 completes after the angle of pitch, azimuth and the polarizing angle calculating of satellite with respect to portable satellite receiver, also comprises a step that is related to corrected azimuth according to portable satellite receiver and satellite longitude.

Further, described satellite-signal power calculation step adopts Split Radix FFT Algorithm:

If sequence x (n) length is N, the expression formula X of split-radix FFT (k) can be represented by the formula:

$\left\{\begin{array}{cc}X\left(2k\right)=\underset{n=0}{\overset{N/2-1}{\mathrm{\Σ}}}{x}_2\left(n\right)W_N^{2\mathrm{kn}}=\mathrm{DFT}\left[x_2\left(n\right)\right]& 0\≤k\≤N/2-1\\ X(4k+1)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^1\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^1\left(n\right)\right]& 0\≤k\≤N/4-1\\ X(4k+3)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^2\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^2\left(n\right)\right]& 0\≤k\≤N/4-1\end{array}\right.;$

Wherein,

$\left\{\begin{array}{cc}{x}_2\left(n\right)=\left(n\right)+x(n+N/2)& 0\≤n\≤N/2-1\\ x_4^1\left(n\right)=[x\left(n\right)-\mathrm{jx}(n+N/4)-x(n+N/2)+\mathrm{jx}(n+3N/4)]W_N^n& 0\≤n\≤N/4-1\\ x_4^2\left(n\right)=[x\left(n\right)+\mathrm{jx}(n+N/4)-x(n+N/2)-\mathrm{jx}(n+3N/2)-\mathrm{jx}(n+3N/4)]W_N^n& 0\≤n\≤N/4-1\end{array}\right.$

And $W_N^n=e^{-j2\mathrm{\πn}/N}.$

The invention has the beneficial effects as follows:

1) adopt manual coarse adjustment mode to replace traditional mechanization coarse adjustment mode, easy to use, coarse adjustment speed is fast;

2) according to parameter and the autonomous computer azimuth angle of receiver local position, the angle of pitch and the polarizing angle of wanting locking signal satellite, counting accuracy is high, speed is fast, and intelligent degree is high, easy to use;

3) interface of visual terminal shows the signal strength signal intensity in bandwidth in trim process in real time, shows that intuitively whether the result of fine setting operation is accurate, finely tunes easy to operate and speed is fast;

4) consider azimuth, the angle of pitch and polarizing angle, adjust the polarizing angle oscillator that makes to polarize and adjust to the direction consistent with electromagnetic wave, the signal strength signal intensity maximum of oscillator induction, avoiding occurring that polarization disturbs, and makes reception the best, higher to star accuracy;

5) first detect the signal strength signal intensity of current reception, obtain progressive minimizing bandwidth after maximum point, there is no the restriction of amount of bandwidth, make user see more clearly;

6) receive the descending beacon signal of satellite to realize the measurement of signal strength signal intensity, without by antenna transmission signal, can effectively avoid facing the impact that star disturbs, make the measuring accuracy of satellite-signal intensity higher;

7) complete after the angle of pitch, azimuth and the polarizing angle calculating of satellite with respect to portable satellite receiver, be related to corrected azimuth according to the longitude of portable satellite receiver and satellite, contribute to further to improve satellite locking accuracy;

8) applied widely, not only applicable to portable receiver, can also be applicable to well PTT, quiet in the satellite reception machine equipment such as exceedingly high line;

9) intuitively and promptly realize lock star by the visual terminal with data processing function, can greatly improve the accuracy of conventional portable receiver locking satellite signal, thereby effectively promote the communication reliability of satellite communication system.

Brief description of the drawings

Fig. 1 is the geometry schematic diagram of computer azimuth angle, the angle of pitch, polarizing angle;

Fig. 2 is coarse steps flow chart of the present invention;

Fig. 3 is trim step flow chart of the present invention.

Embodiment

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail, but protection scope of the present invention is not limited to the following stated.

A method for portable satellite receiver quick lock in satellite, it comprises a coarse steps and a trim step.

As shown in Figure 2, coarse steps comprises following sub-step:

S101: utilize positioner to determine position and the orientation of portable satellite receiver;

S102: the satellite of selecting wish locking;

S103: according to the positional information of satellite and portable satellite receiver, calculate the angle of pitch, azimuth and the polarizing angle information of this satellite with respect to portable satellite receiver by portable satellite receiver;

S104: manually adjust the angle of portable satellite receiver according to each angle information, make the satellite of its rough alignment wish locking, complete coarse adjustment.

As shown in Figure 3, trim step comprises following sub-step:

S201: on coarse adjustment basis, receive the descending beacon signal of satellite and carry out the satellite-signal power calculation in certain BREATHABLE BANDWIDTH;

S202: the maximum power point that draws satellite-signal;

S203: finely tune the angle of pitch and the azimuth of portable satellite receiver under the power instruction of visual terminal, make it to aim at this maximum power point;

It should be noted that, the interface of the visual terminal of portable satellite receiver shows the signal strength signal intensity in bandwidth in trim process always, whether the result of demonstration fine setting operation directly perceived is accurate: if find in azimuth or angle of pitch adjustment process, the intensity of beacon frequency declines, anisotropy is adjusted in explanation, needs back adjustment; If intensity improves, direction is correct, continues to adjust to this direction; After intensity is raised to certain maximum, start to decline, this maximum is optimum orientation, and azimuth and the angle of pitch are fixed on to this direction.

S204: fine setting polarizing angle is also observed the maximum power point of visual terminal, makes prominent polarizing angle in selected trim process, completes fine setting.

Same, the interface of the visual terminal of portable satellite receiver shows the signal strength signal intensity in bandwidth in trim process always, whether the result of demonstration fine setting operation directly perceived is accurate: if find in polarizing angle adjustment process, the intensity of beacon frequency declines, anisotropy is adjusted in explanation, needs back adjustment; If intensity improves, direction is correct, continues to adjust to this direction; After intensity is raised to certain maximum, start to decline, this maximum is optimum orientation, and polarizing angle is fixed on to this direction.

Further, the positioner described in step S101 comprises GPS locator or electronic compass.

Further, the method for the satellite of the locking of the selection wish described in step S102 is: the satellite of being inputted and selected wish locking by the visual terminal interface of portable satellite receiver.

The computational process of the angle of pitch, azimuth and polarizing angle is as follows:

The connecting line of satellite receiver and fixed statellite is called demand line, demand line projection on the ground, and the camber line between satellite receiver and substar is called the rhumb line of satellite receiver to fixed statellite, and the definite plane of rhumb line and demand line is called azimuth plane.The Due South that azimuth refers to satellite receiver place warp is to the angle forming with azimuth plane in the direction of the clock, represents with ∠ MAN, and the angle of pitch refers to the rhumb line of satellite receiver and the angle of demand line.

Fig. 1 has provided the geometrical relationship between fixed statellite S and satellite receiver A.In figure, A represents satellite receiver, and S represents fixed statellite, and O represents earth the earth's core, B is the warp of satellite receiver A and the intersection point in equator, the intersection point C that the line of O and S is gone up is at the earth's surface called substar, and the camber line AC of ordering by A point and C on earth surface is called rhumb line, the tangent line that AN is AC, AM is the tangent line of AB, face OAS is azimuth, and D is the intersection point of tangent line AM and equatorial plane, and E is the intersection point of tangent line AN and equatorial plane.

If the longitude of satellite receiver A and latitude are respectively and θ ₁, fixed statellite longitude is difference of longitude below specifically provide the required azimuth φ of satellite receiver antenna alignment satellite _a, angle of pitch φ _ewith polarizing angle φ _jformulation process.

Azimuthal computational process is as follows:

Can be obtained by Fig. 1:

AD＝ODsinθ ₁；

${\tan \mathrm{\φ}}_a=\frac{\mathrm{DE}}{\mathrm{AD}};$

The azimuth that can draw satellite receiver antenna by above three formulas:

Utilize azimuth that above formula obtains taking Due South to trying to achieve as benchmark, in accordance with regulations, azimuth is all taking direct north as benchmark, the azimuth on historical facts or anecdotes border, except need to converting according to the accuracy relation of antenna and satellite and position, also will be transformed into the coordinate system that direct north is benchmark.

The computational process of the angle of pitch is as follows:

For obtaining the angle of pitch, be the parallel lines SF of EA, the extended line of OA and SF intersect at a F, known in right-angled triangle AFS by parallel relation:

${\tan \mathrm{\φ}}_e={\tan \mathrm{\φ}}_f=\frac{\mathrm{AF}}{\mathrm{FS}}=\frac{\mathrm{OF}-\mathrm{OA}}{\mathrm{FS}};$

Again:

OF＝OScosα＝(OC+CS)cosα；

FS＝OSsinα＝(OC+CS)sinα；

Therefore have:

${\tan \mathrm{\θ}}_e=\frac{(\mathrm{OC}+\mathrm{CS})\cos \mathrm{\α}-\mathrm{OA}}{(\mathrm{OC}+\mathrm{CS})\sin \mathrm{\α}}=\frac{(R+h)\cos \mathrm{\α}-R}{(R+h)\sin \mathrm{\α}}=\frac{{\cos \mathrm{\θ}}_1\cos \mathrm{\φ}-\frac{R}{R+h}}{\sin \mathrm{\α}};$

In above formula, OA and OC are the distance of satellite receiver apart from earth the earth's core, represent with R, get 6378 kilometers of earth mean radiuss; All geostationary satellites are all distributed in overhead, equator, and its height represents with h, gets 35860 kilometers, brings above formula into and obtains:

Therefore the angle of pitch:

The computational process of polarizing angle is as follows:

The electromagnetic wave of aerial radiation all polarizes, polarization of electromagnetic wave is to define according to electromagnetic wave direction of electric field intensity in communication process, if electromagnetic electric field intensity be projected in direction of propagation vertical plane on track be a straight line, be referred to as linear polarization; If electric field intensity projected footprint is circle or oval, be circular polarization or elliptical polarization, the polarization definition datum of satellite radiation polarization wave polarization and ground level reception antenna is different, and for a satellite receiving earth station, the polarization of its antenna defines taking ground level as benchmark.The electric wave of electric field intensity plane and earth surface is horizontal polarization, and the narrow limit of feed rectangular waveguide mouth is perpendicular to ground.

When the longitude of satellite receiver is when longitude equates in-orbit with satellite, the electric field component of polarized wave just in time parallel (or vertical) in the ground level of satellite receiver, now polarizing angle is zero.As long as satellite receiver and satellite be not on a longitude, just there is an angle in electric field and ground level in the polarized wave that satellite transmission comes, and this angle is called polarizing angle.For the reception having reached, adjust outside the azimuth and the angle of pitch of receiver antenna, also should adjust according to the numerical value of polarizing angle the direction of feed rectangular waveguide mouth, the oscillator that makes to polarize is adjusted to the direction consistent with electromagnetic wave, the now polarization coupling polarization next with satellite transmission completely, the signal strength signal intensity maximum of oscillator induction, reception the best.Its polarizing angle of the satellite receiver of diverse geographic location is also different, and the required theoretical polarizing angle of satellite receiver antenna alignment satellite is:

Further, described step S103 completes after the angle of pitch, azimuth and the polarizing angle calculating of satellite with respect to portable satellite receiver, also comprises a step that is related to corrected azimuth according to portable satellite receiver and satellite longitude.

Further, described satellite-signal power calculation step adopts Split Radix FFT Algorithm:

If sequence x (n) length is N, the expression formula X of split-radix FFT (k) can be represented by the formula:

$\left\{\begin{array}{cc}X\left(2k\right)=\underset{n=0}{\overset{N/2-1}{\mathrm{\Σ}}}{x}_2\left(n\right)W_N^{2\mathrm{kn}}=\mathrm{DFT}\left[x_2\left(n\right)\right]& 0\≤k\≤N/2-1\\ X(4k+1)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^1\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^1\left(n\right)\right]& 0\≤k\≤N/4-1\\ X(4k+3)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^2\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^2\left(n\right)\right]& 0\≤k\≤N/4-1\end{array}\right.;$

Wherein,

$\left\{\begin{array}{cc}{x}_2\left(n\right)=\left(n\right)+x(n+N/2)& 0\≤n\≤N/2-1\\ x_4^1\left(n\right)=[x\left(n\right)-\mathrm{jx}(n+N/4)-x(n+N/2)+\mathrm{jx}(n+3N/4)]W_N^n& 0\≤n\≤N/4-1\\ x_4^2\left(n\right)=[x\left(n\right)+\mathrm{jx}(n+N/4)-x(n+N/2)-\mathrm{jx}(n+3N/2)-\mathrm{jx}(n+3N/4)]W_N^n& 0\≤n\≤N/4-1\end{array}\right.$

And $W_N^n=e^{-j2\mathrm{\πn}/N}.$

Claims (5)

1. a method for portable satellite receiver quick lock in satellite, it comprises a coarse steps and a trim step, it is characterized in that:

Described coarse steps comprises following sub-step:

S101: utilize positioner to determine position and the orientation of portable satellite receiver;

S102: the satellite of selecting wish locking;

S103: according to the positional information of satellite and portable satellite receiver, calculate the angle of pitch, azimuth and the polarizing angle information of this satellite with respect to portable satellite receiver;

S104: manually adjust the angle of portable satellite receiver according to each angle information, make the satellite of its rough alignment wish locking, complete coarse adjustment;

Described trim step comprises following sub-step:

S201: on coarse adjustment basis, receive the descending beacon signal of satellite and carry out the satellite-signal power calculation in certain BREATHABLE BANDWIDTH;

S202: the maximum power point that draws satellite-signal;

S203: finely tune the angle of pitch and the azimuth of portable satellite receiver under the power instruction of visual terminal, make it to aim at this maximum power point;

S204: fine setting polarizing angle is also observed the maximum power point of visual terminal, makes prominent polarizing angle in selected trim process, completes fine setting.

2. the method for a kind of portable satellite receiver quick lock in satellite according to claim 1, is characterized in that: the positioner described in step S101 comprises GPS locator or electronic compass.

3. the method for a kind of portable satellite receiver quick lock in satellite according to claim 1, is characterized in that: the method for the satellite of the selection wish locking described in step S102 is: the satellite of being inputted and selected wish locking by the visual terminal interface of portable satellite receiver.

4. the method for a kind of portable satellite receiver quick lock in satellite according to claim 1, it is characterized in that: described step S103 completes after the angle of pitch, azimuth and the polarizing angle calculating of satellite with respect to portable satellite receiver, also comprises a step that is related to corrected azimuth according to portable satellite receiver and satellite longitude.

5. the method for a kind of portable satellite receiver quick lock in satellite according to claim 1, is characterized in that: described satellite-signal power calculation step adopts Split Radix FFT Algorithm:

If sequence x (n) length is N, the expression formula X of split-radix FFT (k) can be represented by the formula:

$\left\{\begin{array}{cc}X\left(2k\right)=\underset{n=0}{\overset{N/2-1}{\mathrm{\Σ}}}{x}_2\left(n\right)W_N^{2\mathrm{kn}}=\mathrm{DFT}\left[x_2\left(n\right)\right]& 0\≤k\≤N/2-1\\ X(4k+1)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^1\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^1\left(n\right)\right]& 0\≤k\≤N/4-1\\ X(4k+3)=\underset{n=0}{\overset{N/4-1}{\mathrm{\Σ}}}{x}_4^2\left(n\right)W_N^{4\mathrm{kn}}=\mathrm{DFT}\left[x_4^2\left(n\right)\right]& 0\≤k\≤N/4-1\end{array}\right.;$

Wherein,

$\left\{\begin{array}{cc}{x}_2\left(n\right)=x\left(n\right)+x(n+N/2)& 0\≤n\≤N/2-1\\ x_4^1\left(n\right)=[x\left(n\right)-\mathrm{jx}(n+N/4)-x(n+N/2)+\mathrm{jx}(n+3N/4)]W_N^n& 0\≤n\≤N/4-1\\ x_4^2\left(n\right)=[x\left(n\right)+\mathrm{jx}(n+N/4)-x(n+N/2)-\mathrm{jx}(n+3N/4){]W}_N^n& 0\≤n\≤N/4-1\end{array}\right.$

And $W_N^n=e^{-j2\mathrm{\πn}/N}.$