JPH05297107A - Navigation system - Google Patents

Abstract

PURPOSE:To construct a navigation system in a small size and enhance the serviceability by receiving radio waves emitted from three or more base stations, sensing their ID codes, calculating the distances using the intensities of the radio waves, and calculating the current position on the map from the position information corresponding to the ID codes. CONSTITUTION:The TDMA signal processing part 15 of a portable telephone set 5 takes out the ID codes of three or more base stations from signals emitted thereby and gives the taken-out ID codes to a CPU 19. An electric field intensity sensing part 25 senses the electric field intensity of the received radio wave and gives the result to the CPU 19. An IC card 22 stores the position information corresponding to the ID code of each base station and also the relevant map information. The ROM 20 of this CPU 19 accommodates a program to calculate the distance on the basis of the intensity of the radio wave emitted by each base station, a program to calculate the current position of the telephone set 5 from the obtained distances and the position information and map information taken out of the card 22, and a program to display the current position on a display 24 together with the map information. According to this constitution, the system can be made compact and applied even to wireless telephone, etc., to lead to enhancement of the serviceability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation system, and more particularly to a navigation system for informing the current position of a mobile communication body.

[0002]

2. Description of the Related Art A conventional navigation system in a mobile communication system is, for example, a satellite system. This satellite system stores map information in a memory, receives a predetermined signal from an artificial satellite, and recognizes the current position on the map information in the memory from this signal. The satellite system displays and outputs the recognized current position on the map information to the display device.

[0003]

However, in such a conventional navigation system, since the signal from the artificial satellite is received and the current position on the map information is recognized, the navigation device itself has a large size. At the same time, it is expensive and cannot be applied to small devices such as wireless telephones, resulting in poor usability. Therefore, the present invention calculates the distance from the mobile communication body to each base station by the electric field strength from at least three base stations, and calculates the current position of the mobile communication body from this distance information and the position information of each base station. Then, the current position is confirmed by collating the current position with the map information, and the notification is output to reduce the size of the navigation system.
The purpose of the invention is to improve its usability by making it inexpensive and applicable to small devices such as wireless telephones.

[0004]

To achieve the above object, the present invention provides a navigation system in which a mobile communication device receives radio waves from at least three base stations to determine the current position of the mobile communication device. A measuring means for measuring the electric field strength of radio waves from at least three base stations; a detecting means for detecting the ID code of at least three base stations; Distance calculation means for calculating distance, base station position storage means for storing position information corresponding to the ID code of each base station, map information storage means for storing map information, and position information and the distance It is characterized by further comprising: a current position calculating means for calculating the current position on the map information; and a notifying means for notifying and outputting the current position together with the map information. In this case, the notification means may be, for example, a display means for displaying and outputting the current position together with the map information, as described in claim 2.
The map information storage means and the base station position storage means of the mobile communication body are, for example, as described in claim 3,
It may be composed of one storage device.

[0005]

According to the present invention, the mobile communication device has at least three mobile communication units.
Radio waves from one base station are received, the distance to each base station is calculated from the electric field strength, and the current position of the mobile communication body is determined. That is, the mobile communication body measures the electric field strengths of the radio waves from at least three base stations by the measuring means, and detects the ID codes of the at least three base stations by the detecting means. Then, the distance from the electric field strength to each base station is calculated by the distance calculating means. Further, the position information corresponding to the ID code of each base station is stored in the base station position storage means, and the map information is stored in the map information storage means. Then, the current position on the map information is calculated by the current position calculation means based on the position information and the distance, and the calculated current position is notified and output together with the map information by the notification means. Therefore, the distance from the mobile communication body to each base station is calculated based on the electric field strength from at least three base stations, and the current position of the mobile communication body is calculated from this distance information and the position information of each base station, The present position can be confirmed by collating the present position with the map information, and the notice information can be output together with the map information. As a result, the navigation system can be miniaturized and can be made inexpensive, and can be applied to a small device such as a wireless telephone, so that the usability can be improved. In this case, by adopting display means for displaying and outputting the current position together with the map information as the informing means, it is possible to easily visually recognize the current position of the mobile communication body together with the map information. Also,
By configuring the map information storage means and the base station position storage means of the mobile communication unit by a single storage device, the storage device can be downsized, and the application to small devices is further facilitated. be able to.

[0006]

EXAMPLES The present invention will be specifically described below based on examples. 1 to 6 are diagrams showing an embodiment of a navigation system according to the present invention. FIG. 1 is a system configuration diagram of a navigation system 1. The navigation system 1 includes a line network 2, a plurality of base stations 3, a mobile phone control station 4, a plurality of mobile phones 5 as mobile communication bodies, and the like. There is. In this navigation system 1, a base station 3 and a mobile phone control station 4 are connected to a line network 2, and the mobile phone 5 and the base station 3 are controlled by the mobile phone control station 4.
Wirelessly communicates with.

In the navigation system 1, the mobile phone 5 wirelessly communicates with the base station 3,
Ordinary telephones and other base stations 3 connected via the line network 2
Telephone communication can be performed with another mobile phone 5 that wirelessly communicates with.

The line network 2 is PSTN (public telephone line network)
And ISDN (Integrated Services Digital Network), etc., and enables communication by lines.

The base station 3 communicates with the mobile phone 5 to enable wireless communication with the mobile phone 5.
Many are located relatively densely in stations and telephone booths. An ID code for identifying each base station 3 is given to each base station 3, and this ID code is used in communication with the mobile phone 5 and the like described later.

The mobile phone control station 4 controls communication by the mobile phone 5 through the base station 3 using the line network 2.

As shown in FIG. 2, the mobile phone 5 includes a microphone 11, a speaker 12, a PCM codec 13, a speech codec 14, and a TDMA (Time Division Multiple A).
ccess) signal processing unit 15, digital modulation / demodulation unit 16,
RF (Radio Frequency) processing unit 17, antenna 18,
CPU (Central Processing Unit) 19, ROM 20,
The RAM 21, the IC card 22, the key operation unit 23, the display unit 24, the electric field strength detection unit 25, and the like are provided.

The mobile phone 5 may be carried by a person and carried around, or may be attached to an automobile or the like, and it can move together with a moving body and perform communication through the base station 3,
Further, the current position of the moving body is informed and output by the navigation processing described later.

In the mobile phone 5, the voice signal input from the microphone 11 is converted into a digital signal by the PCM codec 13, the digital signal is compressed by the speech codec 14 and output to the TDMA signal processor 15. TDM
The A signal processing unit 15 sets a certain frequency to a plurality of mobile phones 5.
Etc. perform signal processing when communicating in a shared communication system by time division, etc., and the digital modulation / demodulation unit 16 modulates the digital signal processed by the TDMA signal processing unit 15 and outputs it to the RF processing unit 17. To do. The RF processing unit 17 converts the intermediate frequency signal into a high frequency signal and transmits the high frequency signal via the antenna 18.

The TDMA signal processor 15 extracts the ID code of the base station 3 from the signal transmitted from the base station 3 in this signal processing and outputs it to the CPU 19.
Therefore, the TDMA signal processing unit 15 has at least 3 units.
It functions as a detection means for detecting the ID code of one base station 3.

In the mobile phone 5, the RF processing unit 17 converts the high frequency signal received by the antenna 18 into an intermediate frequency signal, and outputs the intermediate frequency signal to the digital modulation / demodulation unit 16 and the electric field strength detection unit 25. The digital modulation / demodulation unit 16 demodulates the digital signal and outputs it to the TDMA signal processing unit 15. The TDMA signal processing unit 15 performs signal processing on the signal input in time division and outputs it to the speech codec 14.
The speech codec 14 expands the digital signal and outputs it to the PCM codec 13. The PCM codec 13 converts the digital signal into an audio signal and outputs it to the speaker 12. The speaker 12 outputs the input audio signal in a loud voice.

The electric field strength detector 25 detects the electric field strength of the received radio wave from the output of the RF processor 17, and outputs the detected electric field strength to the CPU 19. Therefore, the electric field strength detection unit 25 is configured to detect at least three base stations 3
It functions as a measuring means for measuring the electric field strength of the radio wave from.

The CPU 19 has a ROM 20 and a RAM 21.
The ROM 20 includes a program for the mobile phone 5 and a distance calculation program for calculating the distance to the base station 3 from the electric field intensity of the radio wave from the base station 10.
The distance and at least three base stations 1 that have calculated the distance
The current position calculation processing program that calculates the current position of the mobile phone 5 on the map information stored in the IC card 22 described later based on the position information of 0 and the calculated current position are displayed and output to the display unit 24 together with the map information ( It stores a notification output processing program for outputting the notification).

The RAM 21 is used as a work memory. As shown in FIG. 3, the RAM 21 stores data relating to a plurality of base stations (usually three base stations) 3 that have received radio waves when performing navigation processing. A base station data area (base station data area A, base station data area B, base station data area C in FIG. 3) and a current position area for storing data of the current position are formed. Each of the base station data areas is, as shown in FIG.
An ID code area that stores the ID code of the base station 3, an electric field strength area that stores the electric field strength P of the radio wave from the base station 3, and a distance area that stores the distance D from the base station 3 to the mobile phone 5. It is divided.

The CPU 19 uses the RAM 21 as a work memory to control each part of the mobile phone 5 in accordance with the program in the ROM 20 to perform the process as the mobile phone 5 and also to perform the current position calculation process and the notification output process. To do.

Therefore, the CPU 19 functions as a distance calculating means for calculating the distance to each base station 3 from the electric field strength P detected by the electric field strength detecting section 25, and at the same time, to the distance to the base station 3 and the base station 3. It functions as a current position calculating means for calculating the current position of the mobile phone 5 on the map information based on the position information.

The IC card 22 stores position information and map information corresponding to the ID code of each base station 3. Based on the position information and map information stored in this IC card 22, the CPU 19 causes the above-mentioned information. Distance calculation processing, current position calculation processing, notification output processing, etc. are performed.

Therefore, the IC card 22 functions as map information storage means for storing map information and base station position storage means for storing position information of the base station 3 corresponding to the map information.

The key operation unit 23 is provided with various keys necessary for the mobile phone 5 and various keys necessary for outputting the current position, and the CPU 19 scans the key operation unit 23 to perform key operations. It is detected and processing is performed according to the operation content.

The display unit 24 is, for example, a liquid crystal display device, and is driven and controlled by the CPU 19 so that the mobile phone 5 can be controlled.
And the data necessary for the mobile communication body of the navigation system 1 are displayed and output.

Next, the operation will be described. The navigation system 1 performs wireless communication between the base station 3 and the mobile phone 5, and wireless communication between a normal telephone connected to the base station 3 via the line network 2 and another base station 3. Telephone communication is performed with the mobile phone 5.

The navigation system 1 also performs navigation processing. That is, the mobile phone 5 receives radio waves from at least three base stations 3, calculates the distance to each base station 3 from the electric field strength of the radio waves from each base station 3, and calculates the distance and each base station 3 The current position of the mobile phone 5 is calculated from the position information of. The calculated current position is notified and output together with the map information.

Incidentally, when the telephone call is not normally made, the base station 3 transmits the identification signal at a predetermined time interval.

The navigation processing will be described below. Now, the mobile phone 5 installed in the automobile is shown in FIG.
It is assumed that the base stations 3A, 3B and 3C are installed as the base station 3 near the mobile phone 5 as shown in FIG.

When it is desired to know the current position on the side of the mobile phone 5, the key operation section 23 of the mobile phone 5 is operated to set the navigation mode. When the mobile phone 5 scans the key operation unit 23 and detects that the key operation has been performed, as shown in FIG. 6, the electric field strengths of the base stations 3A, 3B, and 3C are arranged in descending order of electric field strength. Is measured and the measured electric field strength P is stored in each electric field strength area in the RAM 21 (step S1).

The electric field strength detector 25 detects the electric field strength P of the radio wave received by the antenna 18 and processed by the RF signal processor 17 and outputs it to the CPU 19. CPU1
9 stores the electric field intensity P input from the electric field intensity detector 25 in the RAM 21.

Next, the portable telephone 5 uses the signal of the radio wave in which the electric field strength P has been detected to determine the I
The D code is detected and stored in the ID code area of the RAM 21 (step S2). The detection of this ID code is performed by the TDMA signal processing unit 15 as described above, and the TD
The MA 15 outputs to the CPU 19. The CPU 19 stores the received ID code in the ID code area of the corresponding base station data area of the RAM 21.

When the ID code is detected and stored in the RAM 21, the electric field strength P is read out from the RAM 21 and the distance D from the electric field strength P to the base station 3 which has transmitted the radio wave of the electric field strength P is calculated. The distance D
It is stored in the distance area of the corresponding base station data area (step S3). Calculation of this distance D is performed by the three base stations 3
For each of.

When the distance D to each base station 3 is calculated, each base station 3 stored in the IC card 22 in correspondence with each calculated distance D to each of the three base stations 3 and the ID code.
From the position information of, the current position of the mobile phone 5 is calculated, for example, by trigonometry, and the calculated current position is determined as the current position on the map information stored in the IC card 22 (step S4).

When the current position is confirmed, the current position is output to the display unit 24 together with the map information, and displayed and output to the display unit 24 (step S5).

Therefore, the distance D from the mobile phone 5 serving as a mobile communication unit to each base station 3 is calculated based on the electric field strengths P from at least three base stations 3, and this distance information and each base station 3 are calculated. The current position of the mobile phone 5 is calculated from the position information, and the current position can be confirmed by collating the current position with the map information, and the notification can be output. As a result, the navigation system 1 can be downsized and can be inexpensive. Therefore, it can be applied to a small device such as a wireless telephone and the usability can be improved.

Further, since the current position is displayed and output on the display unit 24 together with the map information, the current position of the mobile phone 5 can be easily visually recognized together with the map information.

Further, since the map information and the base station position are stored in the IC card 22 of the mobile phone 5, the storage device can be downsized and the application to small equipment can be further facilitated. ..

In the above embodiment, the case where the invention is applied to a mobile phone has been described, but it goes without saying that the invention is not limited to this.

Further, according to the above embodiment, the current position is displayed and output on the display unit, but the present invention is not limited to this.
For example, the current position may be notified and output by voice, or both display output and voice output may be performed.

[0040]

According to the invention described in claim 1, the distance from the mobile communication body to each base station is calculated based on the electric field strengths from at least three base stations, and this distance information and each base station are calculated. The current position of the mobile communication body is calculated from the position information, and the current position can be confirmed by collating the current position with the map information, and the notification can be output, so that the navigation system can be downsized, It can be cheap. As a result, it can be applied to a small device such as a wireless telephone and the usability can be improved.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a navigation system according to an embodiment of the present invention.

FIG. 2 is a block diagram of the mobile phone shown in FIG.

3 is a format diagram of a storage area formed in a part of the RAM shown in FIG.

FIG. 4 is a detailed format diagram of the base station data area of FIG.

FIG. 5 is an explanatory diagram of a current position calculation process.

FIG. 6 is a flowchart showing a navigation process on a mobile phone.

[Explanation of symbols]

 1 Navigation System 2 Circuit Network 3 Base Station 4 Cellular Phone Control Station 5 Cellular Phone 11 Microphone 12 Speaker 13 PCM Codec 14 Speech Codec 15 TDMA Signal Processor 16 Digital Modulator / Demodulator 17 RF Processor 18 Antenna 19 CPU 20 ROM 21 RAM 22 IC card 23 Key operation part 24 Display part 25 Electric field intensity detection part

Claims (3)

[Claims] 1. A navigation system in which a mobile communication body receives radio waves from at least three base stations to determine the current position of the mobile communication body, wherein the mobile communication body has radio waves from at least three base stations. Measuring means for measuring the electric field strength of the base station, detecting means for detecting the ID codes of at least three of the base stations, distance calculating means for calculating the distance from the electric field strength to each base station, and each of the base stations Base station position storage means for storing position information corresponding to the ID code, map information storage means for storing map information, and current position calculation means for calculating a current position on the map information based on the position information and the distance. A navigation system comprising: a notification unit that outputs the current position together with map information. 2. The navigation system according to claim 1, wherein the notification means is a display means for displaying and outputting the current position together with the map information. 3. The navigation system according to claim 1, wherein the map information storage means and the base station position storage means of the mobile communication body are configured by one storage device.