Satellite navigation positioning auxiliary ephemeris data compression and transmission method

A technology of ephemeris data and positioning assistance, applied in the field of satellite positioning, can solve the problems of increasing energy consumption and first positioning time, and achieve the effect of reducing data transmission volume and transmission time, and reducing equipment communication energy consumption

Active Publication Date: 2020-06-19
NURLINK TECH NANJING LTD
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For devices using narrowband communication, such as NB-IoT devices, transmitting more data will also increase energy consumption and time to first fix

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0037] The technical solutions provided by the present invention will be described in detail below in conjunction with specific examples. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0038] After many experiments, we found that in the ephemeris data downloaded by the device from the server each time, some parameters do not change, and some ephemeris data change slightly. For the data that does not change, we can not send it to the device, just tell the device that the data has not changed; for the data that changes, use the reference ephemeris for calculation and compress the calculation result. A bitmap is used to indicate whether the parameters have changed, and the satellite parameters corresponding to the bitmap are shown in Table 1 below:

[0039] Ephemeris parameters corresponding bitmap index satellite health status 6 ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a satellite navigation positioning auxiliary ephemeris data compression and transmission method, which comprises the following steps that: equipment judges whether locally stored ephemeris data is expired or not during positioning, and requests current ephemeris data from a server if the locally stored ephemeris data is expired, and a request message comprises timestamp information of a locally stored ephemeris; after receiving the equipment request, the server searches current ephemeris data, and finds out expired ephemeris data corresponding to the timestamp accordingto the uploaded timestamp information; subtracting all parameters of the current ephemeris from all parameters of the expired ephemeris to obtain the variable quantity of each parameter; 4 bytes are used for representing the change states of satellite numbers and 26 parameters, and 4 bytes and each parameter variable quantity which is not zero are subjected to numerical value compression and packaging to form a data stream. According to the invention, the total transmission data can be compressed to about 70% of the original transmission data only by transmitting the compressed variable quantity and adding a small amount of data to the equipment, so that the data transmission quantity and the transmission time can be effectively reduced in narrowband communication, and the communication energy consumption of the equipment is reduced.

Description

technical field [0001] The invention belongs to the technical field of satellite positioning, and relates to a method for compressing and transmitting satellite navigation and positioning auxiliary ephemeris data. Background technique [0002] The navigation and positioning technology based on navigation satellites has high positioning accuracy and is easy to use. Its related applications have penetrated into all walks of life, and the benefits it brings are becoming more and more significant. Generally, the first positioning time of the device is about 30 seconds. For low-power devices, 30 seconds will cause a lot of energy consumption, which is not conducive to the long-term work of the device. In order to reduce the first positioning time of the device, the server sends the current ephemeris data to assist the device in positioning, thereby shortening the first positioning time of the device and reducing the energy consumption of the device. [0003] When the device perf...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H04L29/06G01S19/25H03M7/30
CPCG01S19/258H03M7/3059H03M7/3066H04L69/04
Inventor 毛刚鲁郁王烨
Owner NURLINK TECH NANJING LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products