阅读说明：本技术 实现针对城市地上轨道交通gps测量数据进行处理的方法 (Method for processing GPS measurement data of urban overground rail transit ) 是由 任明灿 王贵龙 于 2020-06-15 设计创作，主要内容包括：本发明涉及一种实现针对城市地上轨道交通GPS测量数据进行处理的方法,包括从GPS接收机读取GPS数据；判断GPS接收机是否锁定；判断GPS跟踪星数是否大于指定的阈值；统计GPS跟踪卫星信噪比大于设定阈值的数量；判断符合条件的卫星数量是否大于设定阈值；保存符合条件的GPS数据。采用了本发明的实现针对城市地上轨道交通GPS测量数据进行处理的方法,可以方便快速实现对地上轨道交通站厅附近的GPS数据过滤,通过对多条地上轨道交通测试,本方法都能有效滤除站厅附近的GPS数据漂移。本方法实现简单,计算快速,能实时实现对GPS数据的过滤。(The invention relates to a method for processing GPS measurement data of urban ground rail transit, which comprises reading GPS data from a GPS receiver; judging whether the GPS receiver is locked; judging whether the number of the GPS tracking stars is greater than a specified threshold value; counting the number of the signal-to-noise ratios of the GPS tracking satellites which are larger than a set threshold; judging whether the number of satellites meeting the conditions is larger than a set threshold value or not; and storing the qualified GPS data. By adopting the method for processing the urban ground rail traffic GPS measurement data, the GPS data near the ground rail traffic station can be conveniently and quickly filtered, and the method can effectively filter the GPS data drift near the station by testing a plurality of pieces of ground rail traffic. The method is simple to implement, rapid in calculation and capable of filtering the GPS data in real time.)

1. A method for processing GPS measurement data of urban ground rail transit is characterized by comprising the following steps:

(1) reading GPS data from a GPS receiver;

(2) judging whether the GPS receiver is locked, if so, continuing the step (3); otherwise, abandoning the currently received GPS data and continuing the step (1);

(3) judging whether the number of the GPS tracking stars is larger than a specified threshold value, if so, continuing the step (4); otherwise, discarding the currently received GPS data, and continuing the step (2);

(4) counting the number of the signal-to-noise ratios of the GPS tracking satellites which are larger than a set threshold;

(5) judging whether the number of the satellites meeting the conditions is larger than a set threshold value or not, if so, continuing to the step (6); otherwise, continuing the step (3);

(6) and storing the qualified GPS data.

2. The method for processing the GPS measurement data of the urban ground rail transit according to claim 1, wherein the step (1) is specifically as follows:

the base station signal receiver reads the position information, the locking state, the tracking satellite number and the corresponding satellite signal-to-noise ratio from the built-in GPS receiver.

3. The method for processing the GPS measurement data of the urban ground rail transit according to the claim 1, wherein the step (4) is specifically as follows:

and acquiring the signal-to-noise ratio corresponding to the satellite receiver, and counting the number of satellites with the signal-to-noise ratio larger than a specified threshold value.

Technical Field

The invention relates to the field of traffic, in particular to the field of GPS positioning, and specifically relates to a method for processing GPS measurement data of urban ground rail traffic.

Background

When GPS positioning is used in cities, due to shielding of buildings, trees, viaducts and other high-rise buildings, a GPS receiver cannot receive satellite signals or the received satellite signals are weak, and the GPS satellite signals are completely shielded in subways and other tunnels. In another case, the GPS signals received by the GPS receiver arrive at the receiver after multiple reflections by a building, and the arrival time of each signal at the receiver is different, and the signals are superimposed to cause interference, so that the original signals are distorted or errors occur. Due to the above factors, when a navigation system is used in driving in a city, navigation software prompts that the GPS signal is weak. The GPS signal is weak, and when the GPS receiver is used for positioning, the output position may drift, sometimes even by several hundred kilometers.

When the urban ground rail transit is used for base station signal coverage measurement and a GPS receiver is used for recording the running track of a train, the GPS signal in a train carriage is weak, and in addition, the number of common high-rise buildings along the rail transit is large, so that the signal received by the GPS receiver is weaker. One of the main features of the above-ground rail transit is: the station hall layer is generally provided with a rain-proof shed, and when a train enters a station, a GPS signal becomes very weak; when the train is out of the station, the GPS signal becomes strong. After the station is arrived, the GPS signal can become very weak, and the position information output by the GPS receiver can have very large drift, and the confidence of the GPS position information is very low. When the train leaves the station for a period of time, the GPS signal is recovered, the GPS receiver is locked again, the confidence coefficient of the GPS position information in the period of time is very low, and the train is very cluttered when track data display is carried out.

In patent CN 106324626, the method comprises the steps of extracting position data and positioning time of a GPS terminal at a position point, calculating a driving speed of the GPS terminal according to the position data and the positioning time of adjacent position points, calculating an acceleration according to the driving speed and the positioning time of the GPS terminal at adjacent position points, and determining a GPS position drift point according to a numerical relationship between the driving speed of the GPS terminal and a preset speed threshold, or determining a GPS position drift point according to a numerical relationship between the acceleration of the GPS terminal and a preset acceleration threshold. According to the running speed or acceleration of the GPS terminal, the method is not suitable for the ground rail transit in the example to stop at the station when the station stops at the station hall or at the morning and evening rush hour, because the acceleration and the speed are both 0, and the GPS signal in the carriage is unstable when the train is out of the station, the data validity can not be judged according to the method.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a method for processing GPS measurement data of urban ground rail transit, which has the advantages of high calculation speed, high effectiveness and wide application range.

In order to achieve the purpose, the method for processing the urban ground rail transit GPS measurement data comprises the following steps:

the method for processing the GPS measurement data of the urban ground rail transit is mainly characterized by comprising the following steps of:

(1) reading GPS data from a GPS receiver;

(2) judging whether the GPS receiver is locked, if so, continuing the step (3); otherwise, abandoning the currently received GPS data and continuing the step (1);

(3) judging whether the number of the GPS tracking stars is larger than a specified threshold value, if so, continuing the step (4); otherwise, discarding the currently received GPS data, and continuing the step (2);

(4) counting the number of the signal-to-noise ratios of the GPS tracking satellites which are larger than a set threshold;

(5) judging whether the number of the satellites meeting the conditions is larger than a set threshold value or not, if so, continuing to the step (6); otherwise, continuing the step (3);

(6) and storing the qualified GPS data.

Preferably, the step (1) is specifically:

the base station signal receiver reads the position information, the locking state, the tracking satellite number and the corresponding satellite signal-to-noise ratio from the built-in GPS receiver.

Preferably, the step (4) is specifically:

and acquiring the signal-to-noise ratio corresponding to the satellite receiver, and counting the number of satellites with the signal-to-noise ratio larger than a specified threshold value.

By adopting the method for processing the urban ground rail traffic GPS measurement data, the GPS data near the ground rail traffic station can be conveniently and quickly filtered, and the method can effectively filter the GPS data drift near the station by testing a plurality of pieces of ground rail traffic. The method is simple to implement, rapid in calculation and capable of filtering the GPS data in real time.

Drawings

Fig. 1 is a flow chart of a method for processing GPS measurement data of urban ground rail transit according to an embodiment of the present invention.

Fig. 2 shows unfiltered GPS data near a rail transit station hall for implementing the method for processing GPS measurement data of urban ground rail transit according to the present invention.

Fig. 3 shows filtered GPS data near a rail transit station hall for implementing the method for processing GPS measurement data for urban ground rail transit according to the present invention.

Detailed Description

In order to more clearly describe the technical contents of the present invention, the following further description is given in conjunction with specific embodiments.

The method for processing the GPS measurement data of the urban ground rail transit comprises the following steps:

(1) reading GPS data from a GPS receiver;

(2) judging whether the GPS receiver is locked, if so, continuing the step (3); otherwise, abandoning the currently received GPS data and continuing the step (1);

(3) judging whether the number of the GPS tracking stars is larger than a specified threshold value, if so, continuing the step (4); otherwise, discarding the currently received GPS data, and continuing the step (2);

(4) counting the number of the signal-to-noise ratios of the GPS tracking satellites which are larger than a set threshold;

acquiring a signal-to-noise ratio corresponding to the satellite receiver, and counting the number of satellites with the signal-to-noise ratio larger than a specified threshold value;

(5) judging whether the number of the satellites meeting the conditions is larger than a set threshold value or not, if so, continuing to the step (6); otherwise, continuing the step (3);

(6) and storing the qualified GPS data.

As a preferred embodiment of the present invention, the step (1) specifically comprises:

the base station signal receiver reads the position information, the locking state, the tracking satellite number and the corresponding satellite signal-to-noise ratio from the built-in GPS receiver.

As a preferred embodiment of the present invention, the step (4) specifically comprises:

and acquiring the signal-to-noise ratio corresponding to the satellite receiver, and counting the number of satellites with the signal-to-noise ratio larger than a specified threshold value.

In the specific embodiment of the invention, when the base station signal coverage test is carried out along the ground rail transit, the position information output by the GPS receiver carried on the signal receiver needs to be properly processed, so that the method can be applied to the later data analysis. The method mainly aims to solve the problem that when a base station signal coverage test is carried out along the ground rail transit, the output position of a GPS receiver drifts due to the fact that GPS signals are weak, processing of drifting position data is achieved, and the problem of disorder during data display is solved.

The method can be used for processing the position information output by the GPS receiver carried on the signal receiver by large drift due to weakening of the GPS signal caused by rain shelters or other buildings of rail transit station halls when the base station signal coverage test is carried out along the ground rail transit, and filtering the GPS position point with large drift.

The process of the method of the invention is described as follows:

reading GPS data from a GPS receiver; judging whether the current GPS receiver is locked; judging whether the number of the GPS tracked stars is greater than a threshold value; counting the number of the signal-to-noise ratios of the GPS tracking satellites which are larger than a set threshold; according to whether the number of satellites meeting the conditions is larger than a threshold value or not; and storing the qualified GPS data.

The invention discloses a method for processing GPS measurement data of urban ground rail transit, which comprises the following steps:

after a base station signal coverage test is started along the ground rail transit, a base station signal receiver starts to read position information, a locking state, the number of tracking satellites and a corresponding satellite signal-to-noise ratio from an internal GPS receiver.

Step one, judging whether the GPS receiver is locked, if the receiver is not locked, discarding the currently received GPS data, and continuously receiving the new GPS data of the GPS.

And step two, reading whether the satellite number tracked by the current GPS receiver is greater than a specified threshold value, if so, discarding the currently received GPS data, and continuously receiving new GPS data.

And step three, acquiring the signal-to-noise ratio corresponding to the satellite receiver when the number of the satellites tracked by the GPS receiver is larger than a specified threshold value, and counting the number of the satellites with the signal-to-noise ratio larger than the specified threshold value.

And fourthly, if the number of the satellites with the signal-to-noise ratios larger than the specified threshold is smaller than the specified threshold, discarding the current data and continuously receiving new GPS data.

And step five, recording the qualified GPS data.

Before being processed, the GPS data near a certain ground rail transit station hall is shown in fig. 2, the GPS data is greatly drifted near the station hall, the farthest drift point exceeds 200 meters, and the display of coverage data of a base station is seriously influenced when data analysis is carried out at the later stage. The data processed by the method is shown in fig. 3, drift data near the station hall are filtered, and the situation of disorder can not occur when the base station covers the data for display.

By adopting the method for processing the urban ground rail traffic GPS measurement data, the GPS data near the ground rail traffic station can be conveniently and quickly filtered, and the method can effectively filter the GPS data drift near the station by testing a plurality of pieces of ground rail traffic. The method is simple to implement, rapid in calculation and capable of filtering the GPS data in real time.

In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.