JPH07280581A - On-vehicle navigation system - Google Patents

Abstract

PURPOSE:To reduce user's tediousness while GPS data is taken into. CONSTITUTION:While GPS data is taken into, a control part 24 of a navigation system issues channel tuning instruction for television broad cast to a channel tuning part 18 of an on-vehicle television tuner 1. The channel tuning part 18, an channel tuning instruction, makes a PLL circuit 20 seek specified frequency zone, and based on S meter signal inputted from a video detection circuit 15, performs tuning control wherein tuning operation to a station of signal intensity stranger than specified level is repeated. Then, frequency, signal intensity, etc., of a tuned station are stored in a memory 19, and when seeking completes, based on the stored content in the memory 19, the station of strongest intensity is selected, and based on the obtained video signal VDS, the television broadcast of selected station is displayed on a display 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to almanac data,
Also, the present invention relates to a navigation system that receives GPS (Global Positioning System) data such as Femeris data, measures the position of the own vehicle, and draws the measured position of the own vehicle on a map.

[0002]

2. Description of the Related Art Conventionally, satellite receiver GPS receivers are
At least 3 to perform self-positioning using GPS
One, preferably four, satellites are required. Further, it is indispensable to collect GPS data such as almanac data and ferrimes data as information for positioning the own position from each artificial satellite. The almanac data is navigation data transmitted from artificial satellites, and is for capturing and tracking the artificial satellites. The data structure consists of (1) latitude and longitude data, (2) altitude data, and (3) time data. Further, the ferrimes data is precise orbit information of the artificial satellite collected after the acquisition and tracking of the artificial satellite are completed based on the almanac data.

FIG. 3 shows a GPS in a conventional GPS receiver.
6 is a flowchart for explaining a method of receiving information data.
In FIG. 4, the GPS receiver is turned on (step 201) and the almanac data is received from each artificial satellite (step 202). Next, when the acquisition and tracking of each artificial satellite are completed based on the almanac data (step 203), the felimes data of each artificial satellite is received.

When the collection of the ferrimes data is completed (step 205), the pseudo range data of each artificial satellite and the pseudo range change rate data are then collected (step 206). If the collection of the ferrimes data is not completed in step 205, step 204 will be repeated and step 206 cannot be reached.

When the collection of the pseudorange data of each artificial satellite and the respective data information of the pseudorange change rate data is completed (step 207), the Ferimes data of each artificial satellite,
A positioning calculation for determining the self-position is executed based on the pseudo distance data and the pseudo distance change rate data (step 208). On the other hand, in step 207, each GP of each artificial satellite
Step 2 when collection of S data information is not completed
Return to 06 to collect data. In this way, first receive almanac data, and based on the almanac data, each artificial satellite is captured, tracked and pseudorange data of each artificial satellite and pseudorange change rate data until all ferrimes data is collected. Could not be collected, and the positioning calculation for obtaining the self position could not be performed.

[0006]

However, in the conventional method for receiving GPS data information such as the almanac data and the ferrimes data, the almanac data and the ferrimes data are first received immediately after the power is turned on. Etc. must collect GPS information.
Therefore, there is a problem that a single GPS receiver requires a considerable amount of time to receive the GPS information data, the positioning calculation cannot be performed, and the self position is difficult to determine. Therefore, while collecting GPS information, some kind of screen is displayed on a display such as a CRT to prevent the user from getting bored. However, since only the screen display can always realize a monotonous screen display, the user is eventually bored. Will end up.

From the above, it is an object of the present invention that the GPS receiver uses GPS for almanac data, ferrimes data, and the like.
An object of the present invention is to provide a vehicle-mounted navigation system that receives a television broadcast during the reception of the data information and displays the television broadcast on the display means, and when reception of the GPS information is completed, switches the vehicle position display to the display means. .

[0008]

According to the present invention, there is provided a vehicle-mounted navigation system, a first receiving means for receiving GPS data information included in satellite radio waves transmitted from an artificial satellite, and a television broadcast. Second receiving means for receiving, switching means for selectively switching the first and second receiving means, display means for displaying information received by the receiving means switched by the switching means, and the switching means And a control means for controlling whether or not the GPS data information is received by the first receiving means.

[0009]

The control means controls the switching means depending on whether or not the GPS data information is received by the first receiving means to selectively switch and display the position of the own vehicle by television broadcasting and GPS.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a principal block diagram showing a vehicle-mounted navigation system according to an embodiment of the present invention. First,
To describe the configuration, 1 is a television tuner and 2 is a navigation device. In the television tuner 1, 11 is an antenna, 12 is a high frequency amplifier circuit, 13 is a frequency conversion circuit for converting to an intermediate frequency signal, and 14 is a video intermediate frequency amplifier circuit, which generates a video / audio intermediate frequency signal.

Reference numeral 15 is a video detection circuit which receives the video / audio intermediate frequency signal and outputs the video signal VDS, and 16 is an audio receiving circuit which receives the video / audio intermediate frequency signal and outputs the audio signal SDS. The voice receiving circuit 16 has a 4.5MHZBPF, FM detection circuit and the like, which are not shown.

Reference numeral 17 is a signal meter for detecting the received electric field strength of the receiving station (broadcasting station) by monitoring the signal strength of the video / audio intermediate frequency signal output from the video detection circuit 15, and 18 is provided in the tuner 1. In addition to performing various tuning control, a tuning control unit having a microcomputer configuration for performing a search control of a receivable frequency in each band according to a TV band tuning command, an FM band tuning command, and an AM band tuning command from the navigation device 1.
Reference numeral 9 is a memory for storing the reception frequency, the reception electric field strength and the like of the station searched by the tuning control unit 18, and 20 is the tuning control unit 1
A PLL circuit for inputting a voltage signal corresponding to the received frequency data FDT from 8 to the high frequency amplifier circuit 12 to tune to a predetermined broadcasting station, 21 is a power switch for supplying power to each part of the vehicle-mounted TV tuner 1, and 22 is a power switch. It is an operation unit for instructing the vehicle-mounted TV tuner to perform various reception controls.

In the navigation device 2, 21 is a GPS antenna for receiving radio waves from a satellite, and 22 is a GPS antenna.
A GPS receiving unit that receives satellite radio waves from the artificial satellite received by the antenna 21, and 23 is GPS information data such as almanac data and ferrimes data included in the satellite radio waves from the artificial satellite received by the GPS receiving unit 22. The signal processing unit 24 for demodulating the signal, 24 is a control unit, selects a predetermined number (for example, 4) satellites most suitable for positioning at that time point using almanac data, and performs positioning calculation of the selected artificial satellite. Calculation unit 2 for performing positioning data S
5. Detecting whether GPS data information such as the almanac data and ferrimes data has been received,
It is composed of a GPS data information detection unit 26 that outputs a detection signal.

27 is a CD-ROM for storing map data
Such as a map data storage unit, 28 is an operation unit equipped with a map search key, a map scroll key, a vehicle position correction key, a route search key, etc., 29 is a display processor, 30 is a map, and is received by the TV tuner 1. A display for selectively displaying the generated television broadcast, and 31 is a power switch for supplying power to each unit of the navigation device. Reference numeral 32 is an ignition switch of the vehicle.

FIG. 2 is a flow chart for explaining the operation of the vehicle-mounted navigation system according to the present invention. The operation of the system of the present invention will be described below with reference to this flowchart.

When the ignition switch 32 is turned on (step 100) and the power switch 31 of the navigation device 2 is further turned on (step 101), the control section 24 causes the power switch 21 of the vehicle-mounted television tuner 1 to operate.
Is automatically turned on (step 102), GPS data information is imported from the artificial satellites via the satellite antenna 21, the GPS receiving unit 22, and the signal processing unit 23, and first, the artificial satellites are captured and tracked based on the almanac data. Done,
When the acquisition and tracking are completed, the ferrimes data of each artificial satellite is imported (step 104). At this stage, the calculation unit 25 of the control unit 24 performs a predetermined positioning calculation using the ferrimes data, the pseudo range data of each artificial satellite, and the pseudo range change rate data, and outputs the positioning data S. Become.

The time required to output the positioning data S is normally 5 minutes to 6 even when the satellite reception condition is good.
It takes 10 minutes or more if the situation is not good. In the conventional system, the user had to spend a long time watching the monotonous display screen, but in the present invention, the channel selection controller 18 of the television tuner 1 issues a television broadcast channel selection command (step 105), the tuning control unit 18 that has received the tuning command causes the PLL circuit 20 to seek a predetermined frequency band, and based on the S meter signal input from the video detection circuit 15, a signal strength of a predetermined level or higher. Tuning control is repeated by repeating tuning to the station having. Then, the frequency and signal strength of the tuned station are stored in the memory 19, and when the seek is completed, the station having the strongest signal strength is tuned based on the stored contents of the memory 19 and the obtained video signal VD
Based on S, the TV broadcast of the obtained station is displayed on the display 30 (step 106).

When the positioning data S is output (step 1
07), that is, when the own vehicle position is obtained, the control unit 24 plots the own vehicle position obtained from the positioning data S on the map data stored in the map data storage unit 27, and the map drawing control display processor 29. (Step 108), the information displayed on the display 30 is switched from the video signal VDS to the map screen (step 10).
9).

When it is desired to switch the display to the television broadcast screen in the map screen display state, the operation section 22 is operated to
The station having the highest reception sensitivity stored in the memory 19 is received. Alternatively, the television broadcast (last channel) received before switching to the map display screen may be received.

Since the seek in step 106 is completed in several tens of seconds, the acquisition of the ferrimes data by the controller 24 is not completed during that time. Therefore,
The user can enjoy the television broadcast until the acquisition of the data is completed.

[0021]

As described above, according to the present invention, the vehicle-mounted navigation system receives the GPS data information contained in the satellite radio wave transmitted from the artificial satellite.
Receiving means, second receiving means for receiving a television broadcast, switching means for selectively switching the first and second receiving means, and information received by the receiving means switched by the switching means. Since the display means and the control means for controlling the switching means according to the presence or absence of GPS data information reception by the first receiving means are provided, the GPS receiver displays the GPS data information such as almanac data and ferrimes data. During the reception, the television broadcast is received and the television broadcast is displayed on the display means, and when the reception of the GPS information is completed, the own vehicle position display can be switched and displayed on the display means, which makes the user bored and irritated during the data acquisition. Can be reduced.

[Brief description of drawings]

FIG. 1 is a principal block diagram showing a vehicle-mounted navigation system that is an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the vehicle-mounted navigation system according to the present invention.

FIG. 3 is a flowchart for explaining a method of receiving GPS data information in a conventional GPS receiver.

[Explanation of symbols]

 1 TV Tuner 2 Navigation Device 17 S Meter 19 Tuning Controller 22 GPS Receiver 24 Controller 29 Display Processor 30 Display

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 5/44 Z

Claims (1)

[Claims] 1. A first receiving means for receiving GPS data information included in satellite radio waves transmitted from an artificial satellite, a second receiving means for receiving a television broadcast, and the first and second means.
Switching means for selectively switching the receiving means, display means for displaying information received by the receiving means switched by the switching means, and the switching means depending on whether GPS data information is received by the first receiving means. An in-vehicle navigation system, comprising: a control unit for controlling.