JPH05327603A - Map display system in mobile station terminal equipment - Google Patents

Abstract

PURPOSE:To display a map around a location where a mobile station terminal equipment itself is resident on a display device. CONSTITUTION:A mobile station 1 makes a call to a map information service station 4 to receive identification information of a base station 2 and coordinate data and calculates a distance between the base station and the mobile station 1 based on a propagation delay timing received from the base station 2, a coordinate represented by the identification information of the base station having a highest reception electric field strength among the base station to which the mobile station 1 is tuned and adjacent base stations is obtained based on data from the map information service station 4 to obtain around the location of the mobile station 1, and a map around the coordinate is displayed on a display device 17. Thus, it is not required to provide a device detecting the position of the mobile station newly and the map around the mobile station is simply displayed by utilizing propagation delay timing from an automobile telephone system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map display system in a mobile station terminal, and more particularly to a map display system in a mobile station terminal of a TDMA digital car telephone system.

[0002]

2. Description of the Related Art A conventional car telephone system is generally an analog system. Further, as a TDMA digital car telephone system, a GSM system (Group-on Special Mobile) in Europe, which will be described later, is described.
le System).

[0003]

The above-mentioned conventional analog type automobile telephone system is of the SCPC type and has no means for knowing the distance between the base station and the mobile station. Could not be displayed.

Further, even in the GSM system, there is no technique for displaying a map on a mobile station.

An object of the present invention is to provide a map display system in a mobile station terminal which displays a map of the vicinity in a mobile station in a TDMA digital car telephone system which has not been conventionally performed.

[0006]

The map display method in the mobile station terminal of the present invention is such that when the base station receives a random access from the mobile station, the burst reception timing does not cause a propagation delay due to the distance to the mobile station. The mobile station notifies the mobile station of the transmission delay correction bit number for detecting how many more bits are delayed and correcting the delay bit number, and the mobile station measures the received electric field strength of the adjacent base station and the identifier of the base station. Is a map display system in a mobile station terminal of a digital car telephone system of the TDMA system, which reads the identifiers of all base stations in the digital car telephone system and the positions on the map in response to a call from the mobile station. A map information service station for returning the indicated map coordinate data to the mobile station is provided, and the mobile station is provided with the map coordinate data of the map information service station. A database having map information data capable of displaying the same coordinates as the data, a display for displaying the map information data read from the database so that the designated coordinates are located at the center of the screen, and the map information service station. The distance between the base station and the mobile station is calculated from the map coordinate data of the base station obtained when a call is made and the transmission delay correction bit number sent from the base station, and the mobile station tunes. Coordinates of a point separated from the first base station by the calculated distance on a line connecting the first base station and the second base station having the largest received electric field strength in the adjacent base station. And a mobile station controller for instructing the display and the database.

[0007]

The present invention will be described below with reference to the drawings. A GSM system will be described as an example of a TDMA digital car telephone system to which the present invention is applied.

The GSM system is an 8-channel TDM
It is a digital car telephone system of A system, and the modulation system is GMSK. FIG. 4 is a diagram showing a frame structure of the GSM system.

As shown in FIG. 4, there are 3 bursts for access.
It is composed of 6-bit data (Data), 41-bit synchronization signal (SYNC), burst rising 8 bits, and falling 3 bits. The F (frequency synchronization) burst consists of 142-bit data (Data) and burst. It consists of 3 bits each of rising and falling,
The burst for S (frame synchronization) includes 78-bit data (Data) and 64-bit training signal (Tra).
inning) and 3 bits each of rising and falling of the burst, B (system information) burst, C (control) burst, T (call) burst, A
The burst for (control signal) is 116-bit data (Da
ta) and a 26-bit training signal (Traini)
ng) and 3 bits each of the rising and falling edges of the burst. One frame is composed of 8 bursts. Further, a plurality of frames are collected to form a multiframe, and each burst has a different meaning depending on the position within the multiframe. The control channel and the call channel have different multiframe structures. The downlink control channel has a 51 multi-frame structure, F (burst for frequency synchronization), S (burst for frame synchronization), B (burst for system information), C (burst for control channel) and I.
(Idle burst) is repeated every 51 frames. An access burst is used in the uplink control channel. The communication channel comprises 26 multiframes, and T
During (call burst), A (control signal burst) and I (idle burst) are alternately inserted once every 13 frames.

FIG. 1 is a block diagram of a digital car telephone system showing an embodiment of a map display system in a mobile station terminal of the present invention.

The base station 2 includes a base station controller 21 for controlling the control channel controller 22 and the traffic channel controller 23, a control channel controller 22 for controlling the control channel transmitter 25 and the receiver 26. A call channel control unit 23 for controlling the call unit 27 and the call unit 28
And a synchronization control unit 24 that sends information necessary for the GSM frame structure shown in FIG. 4 to the control channel control unit 22, the transmission unit 25, the reception unit 26, the speech channel control unit 23, the transmission unit 27, and the reception unit 28. Composed of. The transmission unit 25 transmits the downlink control channel in a 51-multiframe structure by the modulation method GMSK. The receiving unit 16 has an automatic equalizer and detects an access burst, and at the same time, detects how many bits the received burst is received between the mobile station and the base station with respect to the case where there is no propagation delay due to the position. The transmission unit 27 transmits the downlink speech channel in a 26-multiframe structure by the modulation method GMSK. The receiving unit 28 has an automatic equalizer and performs burst detection using the central 26-bit training signal Training, and at that time, the received burst should be received between the mobile station and the base station when there is no propagation delay due to position. It also detects how many bits are behind the position. The base station controller 21 interfaces with the exchange 3. The exchange 3 has an exchange function, and the map information service station 4
Can be routed.

The mobile station controller 11 of the mobile station 1 has a transmitter 1
2, controlling the receiving unit 13, the frequency synthesizer 14, the synchronization control unit 15, to detect the call from the telephone 16 and disconnection,
Control according to it. The frequency synthesizer 14 controls the transmitter 12 and the receiver 13 to the frequency to be tuned instructed by the mobile station controller 11, and the transmitter 12 adjusts the frequency tuned by the frequency synthesizer 14. Burst is transmitted by the modulation method GMSK. The receiver 13 has an automatic equalizer, and detects a burst at the frequency tuned by the frequency synthesizer 14. The synchronization control unit 15 has the same function as the synchronization control unit 24 of the base station 2, and is set by the mobile station control unit 11 at substantially the same time as the synchronization control unit 24 of the base station 2.

Mobile station controller 11, transmitter 12 and receiver 1
3, the synchronization control unit 15 can know the timing of the frame configuration of the base station. When the mobile station 1 is powered on, it sequentially tunes all frequencies allowed by the system and measures its received field strength. Then, tuning is performed to the frequency with the highest received electric field strength, and it is confirmed whether a burst for frequency synchronization (F) is detected.

If the F burst is not detected, the process is repeated until the F burst is detected by tuning to the next highest frequency of the received electric field strength. When the F burst can be detected, the data (Dat) in the frame synchronization (S) burst is next detected.
Read a). Information for frame synchronization is included in this data, and the mobile station 1 sets the synchronization control unit 15 in this synchronization information, and the timing is synchronized with the frame configuration of the base station 2.

Next, the mobile station 1 reads the data (Data) in the burst for system information (S) to know the system information of the base station 2. The system information includes the identification information of the base station 2 and the frequency information of the adjacent base station. Next, the mobile station 1 uses the control (C) burst data (D
ATA) is read and it is detected whether or not the paging information for itself is included therein. When there is no C burst, the mobile station 1 tunes to the frequency of the adjacent base station included in the previous system information, measures the received electric field strength, and reads the base station identifier. As a result, the mobile station 1 tunes to the base station having the strongest received electric field strength, so that the mobile station 1 can select the optimum base station by moving.

Next, the propagation delay correction between the mobile station and the base station at the timing when transmitting and receiving the burst signal between the mobile station 1 and the base station 2 will be described. When the mobile station 1 makes a call,
First, the channel allocation request is raised on the uplink control channel by the burst for access, and when the base station 2 receives this,
The number of bits deviated from the position to be received when there is no propagation delay is detected simultaneously with the detection of 41 bits of the synchronization signal SYNC of the access burst. The propagation delay detected at this time is converted to timing advance (hereinafter referred to as TA
It is called). The base station 2 codes this TA in the channel assignment message and sends it to the mobile station 1.
The mobile station 1 advances the next burst transmission timing by this TA and sends out a burst signal. As a result, the propagation delay due to the distance between the mobile station 1 and the base station 2 is corrected. Even during the call, the base station 2 detects how late the training signal (Training) for the call (T) is received, and sends TA to the mobile station 1 by the burst for the control signal (A) for the downlink. Give instructions.

In the present embodiment, the mobile station 1 has a database 18 of maps which can be displayed by coordinates, and a display 17 which reads and displays map information from the database 18 centered on the coordinates designated by the mobile station controller 11. ing.

Next, the operation of this embodiment will be described with reference to FIG. FIG. 3 is a sequence chart for explaining the flow of messages in FIG.

The mobile station controller 11 indicates that the mobile station 1 has called to the map information service station 4 to display a map.
, The mobile station control unit 11 sends Data for access burst to the transmission unit 12, and instructs the frequency synthesizer 14 to specify the frequency of the uplink control channel. Transmitter 12
Then, the frequency synthesizer 14 tunes to the frequency of the uplink control channel, and the data from the mobile station controller 11 is transmitted to the base station 2 as an access burst according to a transmission timing instruction from the synchronization controller 15. This access burst becomes a channel allocation request from the mobile station 1 to the base station 2.

At the base station 2, the reception unit 26 tuned to the uplink control channel detects an access burst, and at the same time, the reception timing instructed by the synchronization control unit 24 (this timing is an access timing when there is no propagation delay). It is also detected how many bits are behind this burst reception timing), and the data in the access burst and the information on the number of bits representing this propagation delay are sent to the control channel control unit 22. The control channel control unit 22 sends this information to the base station control unit 21. In the base station control unit 21, information on the channel assigned to the mobile station 1 and a bit for correcting the propagation delay (timing advance T
The information of A) is sent to the control channel control unit 22, and the control channel control unit 22 sends the channel allocation information (including TA) to the transmission unit 25. The transmission unit 25 sends the channel assignment information to the mobile station 1 in the C burst of the downlink control channel from the transmission timing from the synchronization control unit 24. This is channel allocation from the base station 2 to the mobile station 1. The base station control unit 21 notifies the call channel control unit 23 of the channel assigned to the mobile station 1, and the call channel control unit 23 notifies the receiving unit 28 and the transmitting unit 27 that the channel has been assigned.

The mobile station 1 detects the C burst of the downlink control channel by the receiving unit 13, the receiving unit 13 sends the data to the mobile station control unit 11, and the mobile station control unit 11 sends the data in the local station. If the channel is assigned to the destination, the frequency of the assigned channel is instructed to the frequency synthesizer 14, and the transmitting unit 12 and the receiving unit 13 make the frequency synthesizer 14 operate.
Is tuned to the frequency of the assigned channel.

The mobile station controller 11 stores and holds the TA included in the channel allocation, and the transmitter 12 further stores the TA.
Send to and send call data to the map information service station 1
Send to 2. The transmitting unit 12 transmits the T burst from the mobile station control unit 11 earlier than the transmission timing of the synchronization control unit 15 by TA. Calling data is included in the T burst. This is a call from the mobile station 1 to the base station 2.

When a burst is detected in the assigned channel in the receiving unit 28, Data in the burst is sent to the channel control unit 23, and the speech channel control unit 23 receives this D.
ata is sent to the base station controller 21. Since this data is calling data in the base station control unit 21, it is sent to the exchange 3.
The exchange 3 translates the destination of this call data and knows that it is addressed to the map information service station 4.

The exchange 3 sets a path with the map information service station 4 and sends call data to the map information service station 4.
Upon receiving the call from the mobile station 1, the map information service station 4 sends the map information data as shown in FIG. 5 to the exchange 3. FIG. 5 is a diagram showing an example of map information data of the map information service station in FIG.
Color code BCC0, as an identifier of S0, ... BSn,
.About.BCCn, frequencies Freq0, .about.Freqn, and X and Y coordinate data indicating the position of the map, and includes data of all base stations in the area provided by the car telephone system of this embodiment. The exchange 3 sends the map information data from the map information service station 4 to the base station 2.

In the base station 2, the map information data is transmitted via the base station controller 21 and the call channel controller 23 to the transmitter 27.
Send to. The transmission unit 27 transmits the T burst including the map information data on the previously assigned channel at the transmission timing from the synchronization control unit 24.

When the mobile station 1 detects the T burst in the receiver 13, it sends the data in the burst to the mobile station controller 11. When the mobile station control unit 11 receives all the map information data, the mobile station control unit 11 temporarily stores and holds the map information data and sends data indicating a disconnection request to the transmission unit 12. The transmission unit 12 transmits this data as a T burst earlier than the transmission timing from the synchronization control unit 15 by TA.

When the receiving unit 28 of the base station 2 detects the T burst, the data in the T burst is sent to the communication channel control unit 23 and further to the base station control unit 21. When the base station control unit 21 finds that this data is a disconnection request, it releases the channel allocated to the mobile station 1 and reports to the exchange 3 that the mobile station 1 has requested the disconnection. Upon receiving the disconnection request, the exchange 3 clears all the information about the mobile station 1 and disconnects the path to the map information service station 4.

In the mobile station control unit 11 of the mobile station 1, after the disconnection process is completed, the TA and map information data stored and retained,
From the identifier of the base station with which the mobile station 1 is tuned and the identifier of the base station with the largest received electric field strength in the adjacent base station, the coordinates of the base station with which the mobile station 1 is tuned and the base station with the largest received electric field strength in the adjacent base station Is read and the center coordinates of the map displayed on the display 17 are calculated.

Next, the mobile station controller 11 instructs the display 17 on the calculated coordinates. The display 17 reads the map data from the database 18 centered on the designated coordinates and displays it so that the designated coordinates are located at the center of the display.

Finally, a method of obtaining the center coordinates of the map display in this embodiment will be described with reference to FIG. FIG. 2 is a diagram for explaining the principle of relative position detection in the mobile station shown in FIG.

It is assumed that the mobile station 1 is in tune with the base station E (BSE), and the base station G (BSG) of the adjacent base stations has the highest received electric field strength. Here, when the mobile station 1 makes a call to the map information service station 4 in the hope that the map near the position of the mobile station is displayed on the display 17, the BSG has the strongest received electric field strength in the adjacent base station. Remember that. The coordinates (a5, b5) of BS5 and the coordinates (a7, b7) of BS7 are read from the map information data from the map information service station 4. Since TA is the information on the number of bits, the propagation delay time is calculated from the bit rate,
It is multiplied by the speed of light and half of the result is the distance d between the base station and the mobile station. When a map is displayed on the display, the center of the display is set to the coordinates (X, Y) of the mobile station 1 represented by the following equation, and a map centered around the position where the mobile station 1 is located is displayed on the display 17. You can

[0032]

[0033]

As described above, the present invention has the effect that it is possible to display the map near the mobile station terminal by making a call to the map information service station.

[Brief description of drawings]

FIG. 1 is a block diagram of a digital car telephone system showing an embodiment of a map display system in a mobile station terminal of the present invention.

FIG. 2 is a diagram for explaining the principle of relative position detection in the mobile station shown in FIG.

FIG. 3 is a sequence chart illustrating a message flow in FIG.

FIG. 4 is a diagram showing a frame structure of a GSM system.

5 is a diagram showing an example of map information data of a map information service station in FIG.

[Explanation of symbols]

 1 Mobile Station 2 Base Station 3 Switch 4 Map Information Service Station 11 Mobile Station Controller 12, 25, 27 Transmitter 13, 26, 28 Receiver 14 Frequency Synthesizer 15 Synchronization Controller 16 Telephone 17 Display 18 Database 21 Base Station Controller 22 control channel control unit 23 call channel control unit 24 synchronization control unit

Claims (1)

[Claims] 1. The base station detects how many bits the burst reception timing is delayed from when there is no propagation delay due to the distance to the mobile station when receiving random access from the mobile station, and corrects this delay bit number. Of the transmission delay correction bit number to the mobile station, the mobile station measures the received electric field strength of the adjacent base station and reads the identifier of the base station, and a map display on the mobile station terminal of the TDMA digital car telephone system. A map information service station which sends back to the mobile station the identifiers of all the base stations in the digital car telephone system and the map coordinate data indicating the position on the map in response to a call from the mobile station. And the mobile station has a database having map information data capable of displaying the same coordinates as the map coordinate data of the map information service station. And a display for displaying the map information data read from the database so that the designated coordinates are located at the center of the screen, and the map coordinate data of the base station obtained when the map information service station is called. And the number of the transmission delay correction bits sent from the base station, the distance between the base station and the own mobile station is calculated, and the first base station and the adjacent base station to which the own mobile station is tuned At the point connecting the second base station having the highest received electric field strength at a distance away from the first base station by the calculated distance, and instructing the display and the database to move. A map display method in a mobile station terminal, comprising a station control unit.