JPS6395600A - Receiver for mobile communication - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a mobile communication receiving device that receives transmission signals from moving objects such as automobiles, aircraft, and ships.

[Essentials of invention]

The present invention provides a mobile communication receiving device that receives transmission signals from moving objects such as automobiles, aircraft, ships, etc. based on position data transmitted from the moving object, by referring to a reference time and a time difference correction table. By calculating the local time at the sending location and displaying the local time on the display means, misunderstandings of the message due to time differences can be avoided.

[Conventional technology]

A communication system has previously been proposed that uses geostationary satellites to perform two-way communication between mobile objects such as automobiles, aircraft, ships, and the like, and communication centers on the ground.

Figure 4 shows the main points of this satellite communication system.
1) is a ground communication center, (2) is a geostationary satellite, and (3) is a truck carrying a mobile communication device.

In this communication system, specific messages such as ``What time will I arrive?'' are sent between a trunk (3), which is a mobile body, and a communication center (1), which is a transportation company to which the trunk (3) belongs, and which has a mobile communication receiving device. (ETA)J.

You can send and receive information such as "What time are you leaving?"

By the way, the mobile communication device mounted on the truck (3) includes a user unit equipped with a keyboard and a display,
Consists of a transmitter/receiver unit. This user unit is placed near the driver's seat so that the user can operate the keys and view the display. On the other hand, the transmitter/receiver unit is connected to a transmitting/receiving antenna, and this transmitting/receiving antenna is provided at a position exposed to the outside, for example, on a roof.

(Problem to be Solved by the Invention) However, as shown in FIG. ) location For example, there is often a time difference between traveling on Route 70 near Denver (Colorado) and the communication center (1), for example, New York City, and in this case, the "What time will you arrive?"
When sending and receiving messages such as "What time are you leaving?", this time difference often becomes a problem and misunderstandings often occur.

In view of this point, the present invention aims to eliminate such misunderstandings of messages.

[Means for solving problems]

As shown in FIG.
3) Based on the position data transmitted from the transmitter, the local time at the transmitting place is calculated by referring to the reference time and the time difference correction table, and this local time is displayed on the display means (4).

[Effect]

According to the present invention, the local time can be obtained by referring to the reference time and the time difference correction table based on the position data from the moving object, for example, the truck (3), and this local time is displayed. You can understand the message by referring to it, and there is no inconvenience of misunderstanding this message.

〔Example〕

Hereinafter, one embodiment of the mobile communication receiving device of the present invention will be described with reference to the drawings.

In this example, a positioning device is provided on a truck (3) which is a moving body in a satellite communication system as shown in FIG. As this positioning device, Loran C,
In addition to being able to use a GPS (global positioning system), a geomagnetic detection device, a gyro, etc., this trunk (3) may also generate a specific signal and calculate it from the reflected signals from a plurality of geostationary satellites.

This positioning device calculates the west longitude and north latitude to obtain the current position data of this trunk (3). In this example, the current position data is included in the transmission data signal from this track (3). The transmission message format of the transmission data signal from this truck (3) is, for example, as shown in FIG. 2, a synchronization code, a specific number ID specifying the truck (3), and position data, for example, 103.30° west longitude.

Latitude 39.15° north, message eg [arriving at 13:00 (ETA) J and error correction code CRC.

The transmitting device provided in this truck (3) is otherwise constructed in the same manner as the conventional one.

In this example, a mobile communication receiving device as shown in FIG. 1 is installed at the transmission center +11, which is a transportation company where this truck (3) is located. In this Figure 1, (5) indicates the static Ii from this truck (3): a reception antenna to which the transmission data signal obtained via the satellite is supplied, and the transmission obtained by this antenna (5). Amplifier (6) data signal
) to the mixing circuit (7) and also to the local oscillator (
8) is supplied to this mixing circuit (7), and the output signal of this mixing circuit (7) is supplied to a data demodulator (9). The position data obtained at the output side of the data demodulator (9) is supplied to the microcomputer (10) as a formant signal as shown in FIG. In this example, a reference clock (11) from which a reference time such as the time at Greenwich Observatory in England can be obtained is provided, and a reference time signal from this reference clock (11) is supplied to a microcomputer (IO). In this example, a time difference correction table (12) in which time difference correction data is stored in a storage device such as a ROM is provided, and the microcomputer (
The correction data read out according to the position data from 10) is supplied to the microcomputer (10). In this microcomputer (10), the track (3
) Location data sent from ) For example, 103.30 west longitude
” , North $!! 39.15°, the local time at the current position of the truck (3) is calculated based on the reference time signal of the reference clock (11) and the correction data from the time difference correction table (12). The information signal from this microcomputer (10) is supplied to the display (4) and displayed on the display (4).In this case, the display (4) has a receiving port as shown in FIG. For example, 86JUL30, reception time for example 12:00.)
Specific number 107 of rack (3). ) The current position of rack (3) is 103.30°W, 39.15°N, and the calculated local time is, for example, 10:00. For example, the message “13
arrive on time. ” is displayed.

(13) indicates a keyboard, and this keyboard (13)
A predetermined signal is input to the microcomputer (10) using the microcomputer (10). The rest of the configuration is similar to the previously proposed mobile communication device.

Since this example is configured as described above, the position data of track (3) of the transmission data signal from track (3),
The local time at the current position of the truck (3) is calculated from the reference time signal from the reference clock (11) and the correction data from the time difference correction table (12), and this local time, for example, 1
Since 0:00 is displayed on the display (4), a message such as "I will arrive at 1:00 p.m." can be accurately determined without misunderstanding.

Therefore, according to this embodiment, there is an advantage that a message from a truck (3) traveling across regions with different time zones can be received without misunderstanding at a communication center, such as a transportation company (1).

In the above embodiment, the present invention was applied to a communication system using a geostationary satellite, but it goes without saying that the present invention can also be applied to other communication systems such as a communication system using a relay station. . Furthermore, it goes without saying that the present invention is not limited to the above-described embodiments, and can take various other configurations without departing from the gist of the present invention.

〔Effect of the invention〕

According to the present invention, since the local time of a mobile object can be known, there is an advantage that messages can be received without misunderstanding even if there is a time difference.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the mobile communication receiving device of the present invention, FIGS. 2 and 5 are diagrams for explaining the present invention, and FIG. 3 is a diagram showing an example of a display. , FIG. 4 is a block diagram showing an overview of an example of a communication system using geostationary satellites. (1) is a communication center, (2) is a geostationary satellite, (3) is a truck, (4) is a display, (10) is a microcomputer, (11) is a reference clock, and (12) is a time difference correction table.

Claims (1)

[Claims] A mobile communication characterized in that, based on position data transmitted from a mobile object, local time at a transmission place is calculated by referring to a reference time and a time difference correction table, and the local time is displayed on a display means. Receiving device.