Mobile Phone Positioning Technology

Currently, mobile phone navigation is commonly divided into two types: mobile phone built-in or external GPS accessories, via satellite navigation, which is currently the most popular Positioning method; second, this article describes how to use the carrier's base station for navigation and positioning.

There is no need to say about GPS navigation. for mobile phones with built-in GPS, such as Nokia, there is a navigation phone called6110The GPS component is built in. While the mobile phone is external, it is a little troublesome. Although my e61i supports GPS, but the Bluetooth GPS accessories need to be purchased separately, the price is about 700, and some compatible non-original accessories, it also sold around 650 yuan. Life is like watching a film. If you can't afford GPS, close your eyes to YY. In short, GPS navigation is a mature and reliable system.

Carrier-based positioning is divided into two types:

1. Location of the GSM Network Base Station

For mobile or Unicom gnetwork (GSM) users, they can receive network signals from the carrier through their mobile phones. A gsm mobile phone can receive signals from nearby base stations as long as it is in the starting state. Based on the cell of the current base station, it can locate the relative location between the mobile phone and these base stations. There are two specific implementations:

A. You can install software on your mobile phone.

This is difficult. Users can install software (such as some Nokia mobile phone engineering models) to measure the role of the current base station. However, to know the actual location of a user, you must know the specific location of the base station and the complete GIS (Geographic Information System) around the base station. Otherwise, you will only see data, useless data ...... However, the geographic distribution of the surrounding base stations is non-public information for operators, which involves enterprise interests and is hard to be provided to the public. Although this method is free of charge, it is hard for ordinary users to achieve it.

B. Carrier-led Positioning System

The operator provides services. When a user initiates a location request, the operator extracts the user location from the user's base station and sends feedback to the user. With the GIS system provided by the carrier, You can implement some simple functions such as positioning and navigation. The specific implementation of this function is through text messages or software provided by the operator, such as recently released by China Mobile.Mobile phone map Software(Please visit this link through your mobile phone or opera ).

2. Positioning of base stations in CDMA Networks

Due to the substantial difference between CCN and GSM, the positioning method of CCN is different from that of GSM. Each CDMA base station of China Unicom has a built-in GPS Positioning System. Qualcomm, its CDMA technology provider, has developed a method that integrates CDMA base station and GPS information:GpsOne.

GpsOne positioning is also achieved through mobile phones. A GpsOne mobile phone can receive signals from GPS satellites and neighboring CDMA base stations at the same time. Based on these signals, it can obtain more precise positioning results than GSM.

Figure GpsOne principle (Source)

Comparison of the three positioning methods:

	GPS satellite	GSM network	GpsOne of CDMA
Positioning Principle	Satellite Positioning with High Precision	Low Network Positioning Accuracy	Satellite + network with higher precision
Positioning implementation	Due to the use of terminal computing → slow speed, terminal power consumption; Strong Dependence on satellites (at least three satellites can be captured) → multiple blind spots	Network Computing, fast, and ineffective, cannot be precisely located	Terminal acquisition + network computing: fast speed, few blind spots, low terminal power consumption (one satellite + one base station can be accurately located, and no satellite can be located only through the base station, the precision is higher than that of the GSM network)
Terminal requirements	GPS mobile phone or GPS + mobile phone	Mobile phone	GpsOne mobile phone
Usage Fee	Free of charge	General charges	General charges

 

I used a mobile card to install the Mobile official "mobile phone map" software. In this way, when we go out to a big city, the location is slightly accurate due to a large number of base stations (the error is generally not more than a block, don't orz), and it is very convenient to find a route; in the countryside, the sky and the sky give you a location, there is no information around, and I don't know where it is. Of course, there are still general national and provincial highways.

There is no doubt that GpsOne is more technical than GPS. However, you still need to pay attention to the precision of Mobile Phone Positioning. On the one hand, a GIS system with precise and informative data is also the focus of attention. The location is accurate, and the location cannot be found.

China Unicom's GIS data level still needs to be used before it can be known. What they provideMobile phone voice navigationThis is a common function of GPS, but accordingIntroduction, There is a funny feature, in Beijing, you can automatically voice a prompt when you are near the intersection with a camera, this "excellent" function, it is a good service for drivers who like to run red lights.

GPS is believed to be the standard for mobile phones in the near future. With the rise of GPS mobile phones, especially the significant application of GpsOne technology, our personal privacy is also worth worrying. With a separate GPS Mobile phone, you can close the GPS terminal to prevent personal location leakage in special channels. with GSM positioning and GpsOne technology, operators can keep abreast of the location information of each person, users can be located as long as they start the system. More realistically, operators are very likely to launch the function of locating users for the benefit of each other. Of course, they will set a threshold, for example, limiting positioning must be known to the target person. However, here is a strange moral circle: If my wife wants to decide on you, do you dare not accept it openly? What do you mean if you're not doing anything bad? More importantly, you only need to send a specific text message with the mobile phone you are positioning, and no notification will be received. In this case, it is not allowed who has borrowed your mobile phone any day. From now on, all your whereabouts have become upright.