US20060170588A1

Movatterモバイル変換

Info

Publication number: US20060170588A1
Application number: US11/341,478
Authority: US
Inventors: Jien-Yang Chang
Original assignee: Mitac International Corp
Current assignee: Mitac International Corp
Priority date: 2005-01-31
Filing date: 2006-01-30
Publication date: 2006-08-03
Also published as: TW200627985A; US7519376B2; TWI257259B; US20070279282A1

Abstract

A tracking method for a cell phone with a positioning device and the system thereof are described. The longitudinal and latitudinal coordinates of a tracked end in a global positioning system (GPS) are sent to a cell phone of a tracking end via a short message service (SMS). After decoding the short message contents, the longitudinal and latitudinal coordinates are displayed in a geographic information system (GIS) installed in the cell phone.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No(s). 941102945 filed in Taiwan, R.O.C. on Jan. 31, 2005, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

The invention relates to a tracking method for a cell phone with a positioning device and the system thereof. In particular, the invention utilizes the SMS (Short Message Service) to transmit the position coordinates from a GPS.

According to statistics, the popularity of cell phones in Taiwan has topped the world. Therefore, the cell phone has become an indispensable tool. Each person has at least one cell phone on the average. A valueable function in the cell phone is to allow the user to find out its position from the closest three base stations by trigonometry. Moreover, geographical information such as food, banks, movie theaters, etc can be transmitted to the user. Sometimes, the base station covers a range of as wide as several kilometers. The error can be as large as hundreds of meters. Thi does not provide the required precision.

Due to recent progress in IC designs and chip productions, manufacturers have developed a global positioning system (GPS) with a small-size chip. Imbedding such a chip in a cell phone enables the cell phone to enjoy the GPS functions. The consumers do not need to spend several hundreds of dollars to carry an additional GPS receiver.

SUMMARY OF THE INVENTION

In view of the foregoing, an object of the invention is providing a tracking method for a cell phone with a GPS and the system thereof. The longitudinal and latitudinal coordinates in the global positioning system (GPS) positioned by a tracking end are sent to a smart phone thereof via the short message service (SMS). After decoding the short message contents, the longitudinal and latitudinal coordinates are applied to a geographic information system (GIS) to obtain the position of the other party.

To achieve the above object, the disclosed tracking system for the cell phone with a positioning device includes a GPS receiving module, a global system for mobile (GSM) communications module, an input module, a central processing unit (CPU), a -display module, and a memory module.

The GPS receiving module receives the position coordinate signals transmitted from the satellites. The GSM communication module sends out the longitudinal and latitudinal coordinates in the SMS. The input module receives settings given by the user. The CPU converts the position coordinate signals into longitudinal and latitudinal coordinates, encodes them into a positioning short message, decodes the coordinates contained in the positioning short message, and determines whether the tracking short message allows tracking. The display module displays the coordinates in the short message on a normal cell phone. If it is a smart phone, then the position of the tracked end can be directly displayed on a map. The position of the user also can be displayed. The memory module stores a phone book and the record of short message transmissions.

Besides, the disclosed tracking method for the cell phone with a positioning device includes the following steps. When a tracking end sends out a tracking short message, the tracked end would receive this short message and checks its source cell phone number to determine whether the tracking is allowed. If it is not a trackable cell phone number, the short message is directly deleted. If it is set as a trackable cell phone number, then the GPS receiving module starts receiving position coordinate signals from the satellites, then the GPS converts the position coordinate signals into longitudinal and latitudinal coordinates, encoding them into a positioning short message, and sending out the positioning short message back to the tracking end. In the end, the tracking end obtains the positioning short message and thus the longitudinal and latitudinal coordinates of the tracked end.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become more fully understood from the detailed description given hereinbelow illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1 shows the system structure of the invention;

FIG. 2 is a flowchart of the disclosed method;

FIG. 3 shows an embodiment of the invention;

FIG. 4 is a flowchart of the method for tracking;

FIG. 5 is a flowchart of the method of positioning;

FIG. 6-ashows the format of a tracking short message according to the invention; and

FIG. 6-bshows the format of a positioning short message according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The system structure of the invention is shown inFIG. 1. It contains the following modules: (A) aGPS receiving module210; (B) aCPU220; (C) aninput module230; (D) adisplay module240; (E) aGSM communication module250; and (F) amemory module260.

TheGPS receiving module210 receives position coordinate signals transmitted fromsatellite110. TheCPU220 converts the position coordinate signals into longitudinal and latitudinal coordinates, encodes the longitudinal and latitudinal coordinates and some information (e.g. title, phone number, name, etc) according to a format into a positioning short message, decodes a received positioning short message into the information contained therein, and determines accordingly whether the tracking short message allows tracking. It further controls and coordinates the operation of various peripheral modules.

Theinput module230 generally refers to a keyboard or a touch-control pad used to receive the settings and inputs from the user, including the system reset of the GPS, the on and off of the tracking function, the phone number of the tracking end. The input command is sent to theCPU220 for processing. The module further includes an emegency transmitting key. After the user presses this key, a short message containing the longitudinal and latitudinal coordinates of -the current position are directly sent to a predetermined short message receiving end. Thedisplay module240 refers to the liquid crystal display (LCD) for display text information on a normal cell phone. If it is installed on a smart phone with the GIS, it can direcly display the position of the trackedend120 on a map. It can also display the position of the user using the information transmitted from theGPS receiving module210.

TheGSM communication module250 sends out the encoded position coordinate message via the SMS. It contains an RF device, a controller, and digital signal processor. In addition to transmitting and receiving communication signals, it can be further used to receive the positioning signal sent from the posiitoning satellite. Thememory module260 stores a phone book and the record of short message transmissions. On ansmart phone160, it further contains a non-volatile memory, such as the flash memory. Not only does it allow the user to install some necessary programs, such as the GIS, it can further be used to store data to lower the burden of the built-in memory.

For illustration purposes, the drawing only shows those devices that are relevant to the invention. Other modules commonly used in regular cell phones, such as the subscriber identify module (SIM) and power supply module, are not explicitly shown.

The disclosed method is shown inFIG. 2. When the tracking end sends out a tracking short message, it should contain the following fields (seeFIG. 6-a):

A header field. This field is filled with a code of a series of special characters to indicate that the short message is in a special format. Once theCPU220 reads this series of special characters, it immediately knows that this is a tracking short message and decodes it to extract the corresponding information;

A state field. This field is filled with a code to representing a corresponding situation. For example,01 represents “I am lost,” and.02 represent “Emergency at home,” and so on;

A name field. This field is used to record the name of the user, stored in advance by the user in thememory module260 to represent the cell phone;

A phone number field. This field is used to record the phone umber of the user; and

A checksum field. It is used to prevent from receiving erroneous short messages during the transmission process. The checksum can be a Hamming code or a cyclic redundancy check (CRC) code.

After thetracking end120 receives this short message, it first checks the number of the source cell phone, determining whether the tracking is allowed. If it is not a trackable cell phone number, the short message is deleted directly. If it is set as a trackable cell phone number, then theGPS receiving module210 receives the position coordinate signals transmitted from the GPS (step510). TheCPU220 converts the position coordinate signals into longitudinal and latitudinal coordinates (step520).

TheCPU220 encodes the longitudinal and latitudinal coordinates into a positioning short message (step530).FIG. 6-bshows the format of a positioning short message. The difference between it and the tracking short message is the additional location field, which is used to record the longitudinal and latitudinal coordinates of the current position of the trackingend120.

The encoded positioning short message is sent out via the GSM communication module250 (step540). Finally, the tracking end obtains the positioning short message from itsGPS communication module250. TheCPU220 decodes to obtain the longitudinal and latitudinal coordinates of the tracked end120 (step550). The goal of the disclosed tracking method is therefore achieved.

With reference toFIG. 3, an embodiment of the invention, when a tracked end or a personal calling forhelp120 is lost or has an accident, a tracking request can be made from the tracking end. Thesatellite110 receives the positioning signal of the current position from the satellite. It sends out the positioning short message via theGSM communication module250. The positioning short message is transferred to the cell phone of the tracking end via an Internet service provider (ISP)130. The tracking end can use the position of the trackedend120 coded in the received positioning short message to find out thecorresponding position140 on the map according to the longitudinal and latitudinal coordinates. If the cell phone is connected to acomputer150 and the computer is installed with a tracking program, then the cell phone can transmit the received positioning short message to the computer to mark down the current position of the trackedend120 on a tracking map. Alternatively, the tracking end is asmart phone160, which is built in with a GPS. In that case, in addition to positioning the tracking end, the smart phone can mark the position of the trackedend120 in a GIS accordingly to the received positioning short message.

FIG. 4 shows the flowchart of the disclosed tracking method. First, the trackedend120 has to turn on the tracking function on his or her cell phone and sets a trackable cell phone number (step310) in thememory module260. If the tracking end sends out a tracking short message (step380), the trackedend120 receives this tracking short message (step320) and checks the number of the source cell phone (step330). The number is compared with the trackable cell phone number set in the memory module to determine whether the tracking should be granted (step340). If it is not a trackable cell phone number, the short message is directly deleted (step350). If it is a trackable cell phone number, then a positioning short message is returned (step370).

When the tracking end receives the returned positioning short message (step390), theCPU220 decodes the positioning short message to obtain the name, phone number, and position coordinates of the tracked end120 (step400) and displays them on thedisplay module240. If the cell phone of the tracking end is connected to acomputer150 or it is asmart phone160 installed with a GIS, then the position of the trackedend120 can be immediately displayed on a map.

Aside from letting the tracking end obtain the position coordinates of the trackedend120, the user can directly press an emergency key to ask for help when in peril. This is illustrated inFIG. 5. When a person encounters an emergency situation, he or she can immediately press the emergency key (step410).

At this moment, theGPS positioning module210 immediately receives the coordinate signal of the current position transmitted from the satellite110 (step420). TheCPU220 converts the position coordinate signals into longitudinal and latitudinal coordinates, and compiles the longitudinal and latitudinal coordinates into a positioning short message containing an emergency code in the state field. The positioning short message is sent out according to the predetermined cell phone number stored in the memory module260 (step430). After receiving the positioning short message (step440), theCPU220 immediately decodes it and displays the person, phone number, and position coordinates of the person asking forhelp120 on the display screen (step450). If the cell phone of the short message receiver is a smart phone with a GIS or is connected to a computer, then the position of the person inneed120 is displayed on a map. The GIS further plans a shortest path according to the person inneed120 and the helper, so that the helper can arrive in the shortest possible time. It also automatically returns a message according to the information in the short message. (step460). This return message ensures that it is not an erroneous call and allows the help to know what is happening.

The reason the invention utilizes the SMS is because it is a function that every cell phone has. Not only it is convenient, the contents of a short message are sufficient to cover the name, longitudinal and latitudinal coordinates, and phone number of the user. Therefore, one may use the short message to readily extract the position of the trackedend120.

Certain variations would be apparent to those skilled in the art, which variations are considered within the spirit and scope of the claimed invention.

Claims

1. A tracking system for a cell phone with a positioning device to transmit longitudinal and latitudinal coordinates contained in a plurality of position coordinate signals obtained from a global positioning system (GPS) from a tracked end to a tracking end via the short message service (SMS), comprising:

a GPS receiving module for receiving the position coordinate signals transmitted from a plurality of satellites;

a central processing unit (CPU) for converting the position coordinate signals into the longitudinal and latitudinal coordinates, and encoding and decoding a positioning short message containing the longitudinal and latitudinal coordinates; and

a global system for mobile (GSM) communications module for transmitting and receiving the positioning short message.

2. The tracking system for a cell phone with a positioning device ofclaim 1 further comprising:

an input module for receiving a plurality of settings from an user;

a display module for displaying the longitudinal and latitudinal coordinates on the cell phone; and

a memory for recording the positioning short messages.

3. The tracking system for a cell phone with a positioning device ofclaim 1, wherein the positioning short message includes a format with the fields of:

a header, filled with the code of a series of special characters so as to indicate the positioning short message is a special format;

a status, filled with a code representing a corresponding situation;

a name, filled with a name representing the user;

a phone number, recording the phone number of the user;

a coordinate, recording the longitudinal and latitudinal coordinates of the cell phone's current position; and

a checksum, filled with a checksum code so as to prevent from receiving an erroneous short message during a transmission process.

4. The tracking system for a cell phone with a positioning device ofclaim 3, wherein the name is keyed in by the user and stored in the memory module.

5. The tracking system for a cell phone with a positioning device ofclaim 1, wherein the positioning short message is obtained from a tracking short message sent from an allowed tracking end.

6. The tracking system for a cell phone with a positioning device ofclaim 5, wherein the tracking short message includes a format with the fields of:

a header, filled with the code of a series of special characters so as to indicate the tracking short message is a special format;

a status, filled with a code representing a corresponding situation;

a name, filled with a name representing the user;

a phone number, recording the phone number of the user; and

7. The tracking system for the cell phone with a positioning device ofclaim 6, wherein the name is keyed in by the user and stored in the memory module.

8. The tracking system for a cell phone with a positioning device ofclaim 1, wherein the display module displays the coordinates in a geographic information system (GIS) installed in the cell phone.

9. A tracking method for a cell phone with a positioning device, comprising:

receiving a position coordinate signal transmitted from a GPS by a tracked end;

converting the position coordinate signal into longitudinal and latitudinal coordinates;

encoding the longitudinal and latitudinal coordinates into a positioning short message;

transmitting the positioning short message to a tracking end; and

obtaining and decoding the positioning short message by the tracking end to obtain the longitudinal and latitudinal coordinates of the tracked end.

10. The tracking method ofclaim 9, wherein the positioning short message includes a format with the fields of:

a status, filled with a code representing a corresponding situation;

a name, filled with a name representing the user;

a phone number, recording the phone number of the user;

11. The tracking method ofclaim 10, wherein the name is keyed in by the user and stored in a memory module.

12. The tracking method ofclaim 9, wherein the tracking end is a trackable phone number recorded in the memory module.

13. The tracking method ofclaim 9, wherein the tracking end has to send a tracking short message to obtain a tracking permission from the tracked end before obtaining the positioning short message from the tracked end.

14. The tracking method ofclaim 13, wherein the tracking short message includes a format with the fields of:

a status, filled with a code representing a corresponding situation;

a name, filled with a name representing the user;

a phone number, recording the phone number of the user; and

15. The tracking method ofclaim 14, wherein the name is keyed in by the user in advance and stored in the memory module.

16. The tracking method ofclaim 13, wherein the positioning short message is transmitted automatically to the tracking end once the tracking short message is received by the tracked end and the tracking permission is confirmed.