Shulou(Shulou.com)06/02 Report--

This article shows you how to get the LBS location in SIM868. The content is concise and easy to understand. It will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.

LBS location method based on Triangle relation

There is more than one positioning technology for LBS. Here the method of this group is briefly illustrated as an example.

The basic principles are relatively simple, as shown in the following figure:

1the coordinates of the three base stations are the known coordinates (X1Magi Y1Magi Z1), (X2Magi Y2Mague Z2) and (X3PowerY3PowerZ3), and the coordinates of the mobile phone are the coordinates to be solved (X0Query Y0Mague Z0). The following formulas can be listed and three equations and three unknowns can be solved. The position of the measured object is calculated by using the geometric trigonometric relation.

L1 ^ 2 = (X1-X0) ^ 2 + (Y1-Y0) ^ 2 + (Z1-Y0) ^ 2

L2 ^ 2 = (X2-X0) ^ 2 + (Y2-Y0) ^ 2 + (Z2-Y0) ^ 2

L3 ^ 2 = (X3-X0) ^ 2 + (Y3-Y0) ^ 2 + (Z3-Y0) ^ 2

What's the use of LBS?

Personally, LBS can be used to upload an approximate location before GPS positioning data, or to provide positioning information through LBS when there is no GPS signal; in addition, according to SIM868, LBS positioning data can help speed up the initial positioning of GPS.

Get the LBS location through the AT instruction. The first part, get ready for work.

AT

OK

Check to see if you can communicate properly

AT+CSQ

+ CSQ: 23Co0

OK

Check signal quality

It is easy to make mistakes when the signal quality is poor.

AT+CREG?

+ CREG: 0Pol 1

OK

Check whether GSM is registered successfully

AT+CGREG?

+ CGREG: 0Pol 1

OK

Check whether GPRS is registered successfully

AT+CGATT?

+ CGATT: 1

OK

View GPRS attachment status

The second part, get LBS coordinates SyntaxExpect ResultDemonstrationAT+SAPBR=3,1, "Contype", "GPRS" OK// setting select GPRS service mode AT+SAPBR=3,1, "APN", "CMWAP" OK// set APNAT+SAPBR=1,1OK// PDP activation, this and TCP/IP use non-conflicting AT+SAPBR=2,1+SAPBR: 1Magne1, "10.59.250.88"

OK can be used without this one.

/ / obtain the IP address AT+CLBSCFG=0,3+CLBSCFG: 0jue 3, "www.c4a.com.cn:3002"

OK can be used without this one.

/ / query the address information currently selected by default using the LBS feature

/ / this address is completely free of charge AT+CLBS=1,1+CLBS: 0116.343534 40.015016550

OK// only acquires latitude and longitude AT+CLBS=4,1+CLBS: 0116.343537, 40.015002, 550, 17Compact, 08Compact, 03recover08pur44purve04.

OK// to get more detailed information, including time information, need + 8 ATM SAP BPR 0pm 1OK hand hand PDP off

Description: most of the LBS location coordinates are synchronized with the NTP synchronization time, only AT+CLBS=4,1 is different, so you can directly add an AT+CLBS=4,1 command after the NTP synchronization time to obtain the LBS location data. NTP synchronization time

The above content is how to get the LBS location in SIM868. Have you learned the knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.