CN103116174B - Global position system (GPS) location map application algorithm based on predictive encoding correction modal - Google Patents

Abstract

The invention discloses a global position system (GPS) location map application algorithm based on a predictive encoding correction modal. The GPS location map application algorithm based on the predictive encoding correction modal includes the following steps: after GPS location information is received through a GPS information receiver, a network delay-time value is calculated out, then an average speed needed next time in GPS location time, a speed needed the next time in the GPS location time and changes of displacements needed the next time in the time of the GPS locating are respectively forecasted out through the GPS location information, and then a position coordinate of a GPS location place need the next time is forecasted out, at last, a corresponding map of the location place is taken out and transmitted to a display terminal. With the steps, the GPS location map application algorithm based on the predictive encoding correction modal is capable of forecasting motion trails of objects and correcting vision map displays of terminal customers. Instantaneity of the customers experiencing the map is better.

Description

GPS map position application algorithm based on predictive coding modification model

[technical field]

The present invention relates to a kind of GPS map position application algorithm, relate in particular to a kind of GPS map position application algorithm based on predictive coding modification model.

[background technology]

GPS (Global Positioning System) system is a kind of radio navigation system, as the new and high technology that is applied to the earliest navigation positioning system, have in global range, at any time, arbitrarily under meteorological condition for user provides the continuously feature of high-precision three-dimensional position, speed and event information, navigation accuracy is high, do not disperse in time, long-time stability are good.

Existing GPS position application is directly to be transferred cartographic information according to GPS value and is shown to client terminal, do not consider the ubiquity of IP network time delay, the time delay bringing due to Internet Transmission, while causing the position of the point that user sees on GPS map, there is certain variation in the actual residing position of current object, actual object is not at GPS correspondence position when after time delay, client sees GPS map, the position that user sees on map is equipped with deviation with object actual bit, in the larger situation of network delay, this position skew is also quite large, if automobile speed per hour is 100km/h, 1 second of network delay, offset deviation is about 30 meters, this place that real-time on-site supervision is had relatively high expectations is just difficult to meet, as remote command dispatching system etc.

[summary of the invention]

The object of the invention is to effectively overcome the deficiency of above-mentioned technology, provide one to take into full account IP network time delay, and can utilize GPS history samples record, a kind of GPS map position application algorithm based on predictive coding modification model that object of which movement curve is predicted.

Technical scheme of the present invention is achieved in that its improvements are, it comprises the following steps:

A) start GPS location periodic refreshing GPS locating information, receive GPS locating information by GPS message recipient, this GPS locating information comprises coordinate figure and the movement velocity of motive objects in the time of sampled point of sampled point, periodic refreshing GPS locating information after receiving;

B) calculate network delay time value;

C) prediction needs the average velocity in time of GPS location next time, and the movement velocity according to the motive objects in step a when the sampled point, dopes the average velocity in the time that next time needs GPS location;

D) prediction needs speed in GPS positioning time and the angle of direction next time, according to the coordinate figure of sampled point in step a, dopes the speed that next time needs in GPS positioning time and the angle of direction;

E) predict the variation of the displacement in the time that next time needs GPS location and need the coordinate of GPS anchor point, need speed in GPS positioning time and the angle of direction by doping in the average velocity in the time that needs GPS location of predicting in the network delay time value in GPS locating information, step b in step a, step c and steps d next time next time, dope the variation of the displacement in the time that next time needs GPS location, and then dope the position coordinates that next time needs GPS located sites;

F) transfer the map that needs GPS anchor point, according to the position coordinates that needs GPS located sites doping in step e next time, transfer the corresponding map of this located sites and be sent to display terminal;

G) repeating step b is to step g.

In described step a, got sampled point A, B, C, the coordinate at sampled point A place is (X1, Y1), and the speed of motive objects in the time of A point is V1; The coordinate at sampled point B place is (X2, Y2), and the speed of motive objects in the time of B point is V2; The coordinate at sampled point C place is (X3, Y3), and the speed of motive objects in the time of C place is V3.

In described step b, network delay time is worth for Δ t.

In described step c, need the time of GPS location identical with network delay time, be Δ t next time; Average velocity in the time that next time needs GPS location doping is V, and meets following formula: V=V3+ (V3-V2).

In described steps d, dope to need speed in GPS positioning time and the angle of direction be θ next time, and to need speed in GPS positioning time and the angle of direction be that θ meets following formula next time:

$\left\{\begin{array}{c}K1=(Y2-Y1)/(X2-X1);\\ K2=(Y3-Y2)/(X3-X2);\end{array}\right.$

tanθ＝|(K2-K1)/(1+K1*K2)|。

In described step e, the variation of the displacement in the time that next time needs GPS location doping is divided into the changes delta X of directions X displacement and the changes delta Y of Y-direction displacement, and can calculate by following algorithm:

$\left\{\begin{array}{c}\mathrm{\ΔX}=V\·\mathrm{\Δt}\·\cos \mathrm{\θ};\\ \mathrm{\ΔY}=V\·\mathrm{\Δt}\·\sin \mathrm{\θ};\end{array}\right.$

Dope and need the position coordinates of GPS anchor point for (X4, Y4) next time, this coordinate figure can calculate by algorithm once:

$\left\{\begin{array}{c}X4=X3+\mathrm{\ΔX};\\ Y4=Y3+\mathrm{\ΔY}.\end{array}\right.$

Beneficial effect of the present invention is: one, the present invention have taken into full account the network delay in practice, utilize prior art to obtain network-induced delay value, make up map location that network delay brings and the difference of actual physical location by predictive coding algorithm again, utilize GPS history samples record, movement locus to object is predicted, makes the real-time of customer experience map better; Two, the present invention, in conjunction with GPS information, comprises the information such as latitude and longitude coordinates and speed, next moment of object is predicted, and revised terminal client vision map and show; Three, the present invention is applied in variously while badly causing in the map positioning system in the larger situation of time delay because of network, and effect is remarkable.

[accompanying drawing explanation]

Fig. 1 is process flow diagram of the present invention.

[embodiment]

Below in conjunction with drawings and Examples, the invention will be further described.

Shown in Fig. 1, a kind of GPS map position application algorithm based on predictive coding modification model that the present invention discloses, it comprises the following steps:

A) start GPS location periodic refreshing GPS locating information, receive GPS locating information by GPS message recipient, this GPS locating information comprises coordinate figure and the movement velocity of motive objects in the time of sampled point of sampled point, for example: get three sampled point A, B, C, the coordinate at sampled point A place is (X1, Y1), the speed of motive objects in the time of A point is V1; The coordinate at sampled point B place is (X2, Y2), and the speed of motive objects in the time of B point is V2; The coordinate at sampled point C place is (X3, Y3), and the speed of motive objects in the time of C place is V3; Receive periodic refreshing GPS locating information after GPS locating information;

B) calculate network delay time value, have at present many methods of obtaining network delay time value, can use by directly transplanting, in the present embodiment, network delay time is worth for Δ t;

C) prediction needs the average velocity in time of GPS location next time, and the movement velocity according to the motive objects in step a when the sampled point, dopes the average velocity in the time that next time needs GPS location; In the present embodiment, the time value that next time needs GPS location with network time value identical, be Δ t, need the average velocity in time that GPS locates is V next time, and this average velocity V predicts by following formula: V=V3+ (V3-V2);

D) prediction needs speed in GPS positioning time and the angle of direction next time, according to the coordinate figure of sampled point in step a, dopes the speed that next time needs in GPS positioning time and the angle of direction; In the present embodiment, need speed in GPS positioning time and the angle of direction is θ next time, and this angle meets following formula:

$\left\{\begin{array}{c}K1=(Y2-Y1)/(X2-X1);\\ K2=(Y3-Y2)/(X3-X2);\end{array}\right.$

tanθ＝|(K2-K1)/(1+K1*K2)|；

Can be obtained the value of sin θ and cos θ by the value of tan θ;

E) predict the variation of the displacement in the time that next time needs GPS location and need the coordinate of GPS anchor point, by the GPS locating information in step a, network delay time value Δ t in step b, in average velocity V in the time that next time needs GPS location of predicting in step c and steps d dope need speed in GPS positioning time and the angle theta of direction next time, dope the variation of the displacement in the time that next time needs GPS location, the variation of this displacement is divided into the changes delta X of directions X displacement and the changes delta Y of Y-direction displacement, the value of Δ X and Δ Y can calculate by following algorithm:

$\left\{\begin{array}{c}\mathrm{\ΔX}=V\·\mathrm{\Δt}\·\cos \mathrm{\θ};\\ \mathrm{\ΔY}=V\·\mathrm{\Δt}\·\sin \mathrm{\θ};\end{array}\right.$

If needing the position coordinates of GPS anchor point is (X4, Y4) next time, this position coordinates can calculate by following algorithm:

$\left\{\begin{array}{c}X4=X3+\mathrm{\ΔX};\\ Y4=Y3+\mathrm{\ΔY}.\end{array}\right.$

F) transfer the map that needs GPS anchor point, according to the position coordinates (X4, Y4) that needs GPS located sites doping in step e next time, transfer the corresponding map of this located sites and be sent to display terminal;

G) repeating step b is to step g.

As can be seen here, the present invention has taken into full account the network delay in practice, utilize prior art to calculate network delay time, make up map location that network delay brings and the difference of actual physical location by above-mentioned algorithm, in the above-described embodiments, it is the record that uses GPS history samples data, as latitude and longitude coordinates and velocity information etc., movement locus to object next positioning time is predicted, having revised terminal client vision map shows, make the real-time of customer experience map better, and the present invention is applied in various while badly causing in the map positioning system in the larger situation of time delay because of network, effect is remarkable.

Described above is only preferred embodiment of the present invention, and above-mentioned specific embodiment is not limitation of the present invention.In technological thought category of the present invention, can there is various distortion and modification, retouching that all those of ordinary skill in the art make according to above description, revise or be equal to replacement, all belong to the scope that the present invention protects.

Claims (6)

1. the GPS map position application algorithm based on predictive coding modification model, is characterized in that: it comprises the following steps:

A) start GPS location periodic refreshing GPS locating information, receive GPS locating information by GPS message recipient, this GPS locating information comprises coordinate figure and the movement velocity of motive objects in the time of sampled point of sampled point, periodic refreshing GPS locating information after receiving;

B) calculate network delay time value Δ t;

C) prediction needs the average velocity in time of GPS location next time, and the movement velocity according to the motive objects in step a when the sampled point, dopes the average velocity V in the time that next time needs GPS location;

D) prediction needs speed in GPS positioning time and the angle of direction next time, according to adopting in step a

The coordinate figure of sampling point, dopes the speed that next time needs in GPS positioning time and the angle theta of direction;

E) predict the variation of the displacement in the time that next time needs GPS location and need the coordinate of GPS anchor point, by the GPS locating information in step a, network delay time value Δ t in step b, in average velocity V in the time that next time needs GPS location of predicting in step c and steps d dope need speed in GPS positioning time and the angle theta of direction next time, dope the changes delta X of variation directions X displacement and the changes delta Y of Y-direction displacement of the displacement in the time that next time needs GPS location, the value of Δ X and Δ Y can calculate by following algorithm:

$\left\{\begin{array}{c}\mathrm{\ΔX}=V\·\mathrm{\Δt}\·\cos \mathrm{\θ};\\ \mathrm{\ΔY}=V\·\mathrm{\Δ}\·\sin \mathrm{\θ};\end{array}\right.$

And then dope the position coordinates that next time needs GPS located sites;

F) transfer the map that needs GPS anchor point, according to the position coordinates that needs GPS located sites doping in step e next time, transfer the corresponding map of this located sites and be sent to display terminal;

G) repeating step b is to step g.

2. the GPS map position application algorithm based on predictive coding modification model according to claim 1, it is characterized in that: in described step a, got sampled point A, B, C, the coordinate at sampled point A place is (X1, Y1), the speed of motive objects in the time of A point is V1; The coordinate at sampled point B place is (X2, Y2), and the speed of motive objects in the time of B point is V2; The coordinate at sampled point C place is (X3, Y3), and the speed of motive objects in the time of C place is V3.

3. the GPS map position application algorithm based on predictive coding modification model according to claim 1, is characterized in that: in described step b, network delay time is worth for Δ t.

4. the GPS map position application algorithm based on predictive coding modification model according to claim 2, is characterized in that: in described step c, need the time of GPS location identical with network delay time, be Δ t next time; Average velocity in the time that next time needs GPS location doping is V, and meets following formula: V=V3+ (V3-V2).

5. the GPS map position application algorithm based on predictive coding modification model according to claim 2, it is characterized in that: in described steps d, dope to need speed in GPS positioning time and the angle of direction be θ next time, and to need speed in GPS positioning time and the angle of direction be that θ meets following formula next time:

$\left\{\begin{array}{c}K1=(Y2-Y1)/(X2-X1);\\ K2=(Y3-Y2)/(X3-X2);\end{array}\right.$

tanθ＝|(K2-K1)/(1+K1 ^*K2)|。

6. the GPS map position application algorithm based on predictive coding modification model according to claim 5, is characterized in that: in described step e,

Dope and need the position coordinates of GPS anchor point for (X4, Y4) next time, this coordinate figure can calculate by following algorithm:

$\left\{\begin{array}{c}X4=X3+\mathrm{\ΔX};\\ Y4=Y3+\mathrm{\ΔY}.\end{array}\right.$