JP2000209071A - On-vehicle reception equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately perform the network follow of the same program with one tuner by changing a reception frequency to the broadcasting frequency of another broadcasting station to broadcasting the same program included in a service area when the position of a vehicle gets out of the service area of the broadcasting station which is receiving broadcast. SOLUTION: A tuner 12 receives the broadcasting wave for the broadcasting station and outputs it to an audio output part 15 and a video output part 16. Corresponding to the instruction of a control part 14, a PLL 13 performs tuning processing so as to receive the broadcasting wave of a frequency to be received by the tuner 12. On the basis of the output of a GPS receiver 21 and a map data base, the control part 14 specifies the vehicle position, judges whether the vehicle position is located within the area of strong electric field intensity or not and whether it is broadcasting of the same program or not and sets the reception frequency of the tuner 12 through the PLL 13. A broadcasting station data base 22 records the service area for each broadcasting station and network sequence stations broadcasting the same program. A clock 23 judges a time zone showing whether the reception frequency can be changed at current time or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-vehicle receiving apparatus capable of appropriately performing network follow.

[0002]

2. Description of the Related Art In an on-vehicle receiving apparatus, the state of a radio wave constantly changes while a vehicle is running. Therefore, if the receiving state of a currently receiving broadcast station deteriorates, another broadcast that is broadcasting the same program is performed. Some stations have a network follow function for searching for a station and switching to a reception frequency of the broadcasting station.

FIG. 6 is a block diagram showing a configuration of a conventional vehicle-mounted receiving apparatus. Hereinafter, description will be made with reference to the drawings.

A distributor 91 distributes a broadcast wave received by an antenna to a main tuner 92 and a sub tuner 82. Reference numeral 92 denotes a broadcast wave of a broadcast station which broadcasts a program desired by a listener, and detects and demodulates the broadcast wave.
5 and a main tuner that outputs to the video output unit 96. Reference numeral 93 denotes a PLL circuit for performing a tuning process so that the main tuner 92 can receive a broadcast wave of a predetermined frequency in accordance with an instruction from the control unit 94. The PLL circuit 93 supplies a frequency corresponding to the reception frequency to a mixer in a superheterodyne tuner. And converts the broadcast wave to be received into an intermediate frequency. 94 controls operation of the receiving device by comparing the reception levels of the broadcast waves received by the main tuner 92 and the sub tuner 82 and setting the reception frequency of the main tuner 92 via the PLL circuit 93 based on the comparison result. This is a control unit that performs the operation, and is configured by a microcomputer or the like. An audio output unit 95 amplifies the audio signal detected and demodulated by the main tuner 92 and outputs the amplified audio signal to a speaker. Reference numeral 96 denotes a video output unit that amplifies the video signal detected and demodulated by the main tuner 92 and outputs the amplified video signal to a liquid crystal display unit or the like. 7 compares the broadcast content received by the main tuner 92 with the broadcast content received by the sub tuner 82,
This is a comparator for determining whether or not the content is the same broadcast content (program). Reference numeral 82 denotes a sub-tuner for searching for another reception frequency of the same broadcast program as the main tuner 92, and outputs a reception level signal and an audio demodulation signal for determining that the broadcast program is the same. 83 is a P for performing a tuning process so that the sub-tuner 82 can receive a broadcast wave of a predetermined broadcast frequency in accordance with an instruction from the control unit 94.
LL circuit.

[0005] In the network follow, when the listener is receiving a broadcast by setting the main tuner 92 to the broadcast frequency of a desired broadcast station, the sub-tuner 82 plays the same program as the broadcast station being received by the main tuner 92. We are always searching for broadcasting stations that are broadcasting. Whether or not the broadcast program is the same is determined by comparing the detection output (audio signal of the broadcast wave) of the main tuner 92 and the sub tuner 82 with the comparator 7. Further, the FM receiving apparatus having the multiplex receiving function recognizes and determines the ID code for identifying the program decoded by the decoder. If the broadcast program is the same, the control unit 94 compares the reception level of the main tuner 92 with the reception level of the sub tuner 82. If the reception level of the main tuner 92 is higher, the reception continues at the current reception frequency. If the reception level of the sub tuner 82 is higher, the reception frequency of the main tuner 92 is To the reception frequency of the sub-tuner 82. In this way, the reception frequency of the main tuner 92 is always changed so that a broadcast wave having a high reception level of the same broadcast program can be received.

[0006]

By comparing the reception levels received by the main tuner 92 and the sub-tuner 82, and setting the reception frequency so that the reception level of the main tuner 92 becomes higher, the same program can be transmitted. The station is switched to the broadcasting station that is broadcasting, so that good reception can always be achieved even when the driving environment changes.

However, the main tuner 9 for receiving broadcasts
2 and a sub-tuner 82 for searching for a broadcast wave with a strong electric field intensity are required, and the cost increases. To check whether the programs are the same,
The M receiving apparatus needs to recognize the ID code using the FM multiplex decoder. In addition, a television receiver requires a comparator for comparing received signals, which also increases the cost.

[0008] It is an object of the present invention to provide an in-vehicle receiving apparatus capable of appropriately performing network follow of the same program with one tuner.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention has a tuner for changing a receiving frequency to receive a broadcast of a desired broadcasting station.
A position for detecting the position of a vehicle in an in-vehicle receiving device having a network follow function for changing to a receiving frequency of the tuner so that a broadcast of another broadcasting station having a good receiving condition broadcasting the same program can be received. Detecting means, service area information storing means in which an area where good reception is possible for each broadcasting station is stored as service area information, and broadcasting frequencies corresponding to a plurality of broadcasting stations broadcasting the same program are stored as network information. Network information storage means, clock means for clocking the current time, and control means for controlling the change of the reception frequency to be prohibited or permitted based on a time zone to which the current time measured by the clock means belongs, When the control means controls to permit the change of the reception frequency, the position of the vehicle is the service area information. When the reception frequency is outside the service area of the currently receiving broadcast station stored in the storage means, the reception frequency is stored in the network information storage means including the position of the vehicle in the service area stored in the service area information storage means. Changing means for changing to a broadcasting frequency of a broadcasting station which broadcasts the same program.

[0010] Further, the position of the vehicle detected by the position detecting means is outside the service area of the currently receiving broadcast station, and the broadcast station broadcasts the same program including the position of the vehicle within the service area. If there is no, there is provided a second changing means for changing the reception frequency to a broadcast frequency of a receivable broadcast station.

[0011] Further, the control means permits the change of the reception frequency when the reception state of the currently received broadcast is extremely deteriorated even in a time zone in which the change of the reception frequency is prohibited. It is characterized by the following.

[0012] The control means may determine whether the change of the reception frequency is prohibited or permitted based on an identification signal for identifying whether the received program is a network program or a local program included in a broadcast wave. It is characterized by the following.

Further, the control means determines whether or not to prohibit or permit the change of the reception frequency by manual operation based on the prohibition time zone information stored in the memory.

Further, the control means determines whether or not to prohibit or permit the change of the reception frequency based on the prohibition time zone information extracted from a broadcast wave and stored in a memory. is there.

[0015]

FIG. 1 is a block diagram showing the configuration of a vehicle-mounted receiving apparatus according to an embodiment of the present invention. Hereinafter, description will be made with reference to the drawings.

Reference numeral 12 denotes a tuner that receives a broadcast wave of a broadcast station broadcasting the contents desired by the viewer, detects and demodulates the broadcast wave, and outputs the detected wave to the audio output unit 15. 13 is a control unit 14
Is a PLL circuit for performing a tuning process so that a broadcast wave having a frequency to be received by the tuner 12 can be received in accordance with an instruction from the control unit 14. Tuner 12
Is a circuit to be supplied to the mixing circuit. 14 is GP
A process of specifying the vehicle position based on the output of the S system 21 and a map database (not shown), and determining whether the specified vehicle position is an area having a strong electric field strength (hereinafter, referred to as a service area) in which reception is possible. And whether or not the broadcast is the same program, and based on the result, the PLL circuit 1
A control unit for controlling the operation of the receiving device, such as setting the receiving frequency of the tuner 12 via the control unit 3, and is constituted by a microcomputer or the like. Reference numeral 15 denotes an audio output unit that amplifies the audio signal detected and demodulated by the tuner 12 and outputs audio from a speaker. Reference numeral 16 denotes a video output unit that amplifies a video signal detected and demodulated by the tuner 12 and outputs the amplified video signal to a liquid crystal display unit or the like. Reference numeral 21 denotes a GPS system that detects a vehicle position using radio waves from artificial satellites. Reference numeral 22 denotes a broadcast station database in which a service area for each broadcast station and a network affiliate station (a channel corresponding to the broadcast station for each affiliate) that mainly broadcasts the same program are recorded. It is composed of a magnetic disk, an optical disk, a RAM with a backup power supply, and the like, which retain the stored contents even if the disk is cut off. Reference numeral 23 denotes a clock for determining whether the current time is in a time zone in which the change of the reception frequency is permitted or prohibited.

FIG. 2 is a flowchart of a process performed by the control unit of the vehicle-mounted receiving apparatus according to one embodiment of the present invention. FIG. 3 is a diagram showing an example of a service area and a vehicle position.
(B) is the service area of the A2 broadcast station, (c) is the service area of the B1 broadcast station,
(D) is a service area and a vehicle position of each broadcasting station.
FIG. 4 is a diagram showing a network affiliated station. FIGS. 5A and 5B are diagrams showing frequency change permission / prohibition time zones. FIG. 5A shows an A-series station, and FIG. 5B shows a B-series station. Hereinafter, description will be made with reference to the drawings. This process is repeatedly executed during the operation of the receiving device.

In step S1, a set station in the A-series is received, and the flow advances to step S2. That is, the reception frequency (28 ch) of the tuner 12 is set so as to receive the broadcast of the A1 station (see FIG. 4) of the network A series selected by the viewer. Incidentally, when the flow returns to step S1 again via the affirmative (Y) of step S2 or step S4, the broadcast station (A1 station, 28ch) set by the viewer remains, but via step S7. Then, when returning to step S1 again, the broadcast station (A1 station, 28
ch) has a poor reception condition (outside the service area), so another broadcast station (A2 station, 50c
h) is set (changed).

In step S2, it is determined whether or not it is a network follow prohibition time zone. If it is a prohibition time zone, the process returns to step S1. If not, the process proceeds to step S3. Broadcasting stations belonging to the network A series (A1, A2,...) Do not broadcast the same program over the entire time zone, but use local broadcasting stations such as local weather forecasts and local news. The program is being broadcast at a specific time. If a change is made to the reception channel of another broadcast station in the network A series during such a time zone, a program (local program) different from the currently received program will be received. In order to prevent such a situation, a time zone in which different programs are broadcast (for example, at 7:05 am in FIG.
5 minutes to 8:00 am, 8:50 am to 9:00 am
Minutes, 9:30 am to 10:00 am, etc.) are set as network follow (frequency change) prohibited time zones. As a method of determining the prohibited time zone, data indicating whether the program is a network program (permitted time zone) or a local program (prohibited time zone) is received from the broadcast wave being received, and received based on the received data. Is determined every time. The control unit 14 obtains data on a network program or a local program from a program table or the like in advance.
5 (a) and 5 (b) are stored for each affiliated station, and it is determined which time zone the current time (according to the clock 23) belongs. The user manually sets the start time and end time of the prohibition time zone and the permission time zone, and stores them in the memory in the control unit 14 for each affiliated station as shown in FIGS. There is a method of determining to which time zone it belongs.

In step S3, the current position data of the vehicle is obtained, and the process proceeds to step S4. That is, it is assumed that the vehicle moves from the point A to the point B or from the point A to the point C based on the GPS system 21 and the current position of the vehicle based on the map database (points A, B, C, etc.). Have been identified). In order to determine whether or not the current position of the vehicle is within the service area of each broadcasting station, a map database is not necessarily required, and the vehicle position may be specified by latitude and longitude.

In step S4, the current position of the vehicle is determined to be a setting station in the network A series (for example, A1 station 28ch).
It is determined whether or not the service area is within the service area, and if it is within the service area, the process returns to step S1, and if it is outside the service area, the process proceeds to step S5. That is, the current position of the vehicle specified by the GPS system 21 (for example, FIG.
It is determined whether or not the points (A), (B) and (C) in (d) belong to the service area of the A1 broadcast station (the hatched portion in FIG. 3 (a)). Figure 3 shows the service area for all broadcasting stations
As shown in (a) to (c), an area (service area) in which an electric field strength equal to or greater than a predetermined value is obtained on a map based on latitude and longitude (not necessarily related to a road map, and the area corresponds to latitude and longitude. It is sufficient if they are recorded.) If it is within the service area of the currently receiving broadcasting station (A1 station) (within the hatched area) (when the current position of the vehicle is point A), the process returns to step S1 to receive the current receiving station (A1 station). continue. If the current position of the vehicle is point B or point C, it is outside the service area of station A1 (outside the hatched area) (FIG. 3).
(D)). The A2 broadcast station is a broadcast station that can follow the network of the A1 broadcast station, and the B1 broadcast station is an A1 broadcast station.
The broadcast station cannot follow the network of the broadcast station.

In step S5, another broadcast station and channel of the network A series are searched. That is, since the current position of the vehicle is out of the service area of the A1 station and the reception state is presumed to be poor, another broadcast station of the A series broadcasting the same program is searched from the network affiliated station of FIG.
As shown in FIG. 4, the network affiliated station stores a broadcast station name and a channel (ch) for each stream and is stored in the broadcast station database 22. A1 station, A2 station, A of A series
The three stations are networks that can follow each other,
Search for a broadcasting station whose current position of the vehicle is included in the service area.

In step S6, it is determined whether or not the mobile station is within the service area of the new broadcasting station. If so, the process returns to step S1.
That is, a search is made for a broadcast station and a channel that include the current position of the vehicle in the service area of the network A series. still,
In FIG. 3D, when the vehicle position is point B, a new A
Although it is within the service area of two stations (50 ch), if the vehicle position is at point C, it is within the service area of station B1, so it is determined that it is not included in the service area to be network-followed.

In step S7, the receiving channel is set to the channel of a new broadcasting station of the network A (for example, A2
Station 50ch) and returns to step S1. That is, since the current position of the vehicle is in the service area of the A2 station broadcasting the same program (see FIG. 3D), the receiving channel is switched using this broadcasting station as a network follow station.

In this way, the reception status can be determined based on whether or not the vehicle position is within the service area of the broadcast station database. Since it can be determined from the affiliated station data and the data indicating whether or not it is a prohibited time zone, it is possible to follow the network to an appropriate broadcasting station. Therefore, there is no need for a tuner or a comparator for searching for a broadcast station to be network-followed.
With one tuner, the size and cost of the receiving device can be reduced. In addition, in order to realize the network follow as in this example, it is necessary to newly detect the position of the vehicle by the GPS system. Then, if the existing navigation device is also used without installing a new one, the cost does not increase.

As described above, in this embodiment, the vehicle position is set to G
Since the location is specified by the PS system and its position is compared with each service area of the affiliated station, a sub-tuner for searching for a broadcast station having the same broadcast content with a high reception level is not required. In addition, it is not necessary to compare received data to confirm whether or not the broadcast station is a network-followable broadcast station, and it is possible to reduce the size and cost of the receiving device. Furthermore,
By setting a network follow-up ban,
It is possible to prevent a network follow from being performed unintentionally in a local program or the like.

Incidentally, in the negative (N) of step S6,
Instead of directly returning to step S1, it is determined whether or not the reception level is lower than a predetermined value. If the reception level is lower than the predetermined value, it is determined that the broadcast of the A affiliated station cannot be received any more. A search may be made for a broadcast station (for example, B series). That is, since there is no broadcasting station of the network A series, in order to receive the broadcasting of another affiliated station that is unavoidably broadcasting the desired program, the broadcasting station whose current position is included in the service area is stored in the broadcasting station database 21. Search from. In this case, since the current position of the vehicle is constantly changing, the current position and A are always set so that the A-series broadcast station can receive the signal when the vehicle enters the A-series service area.
The service area of the affiliated station is checked, and if there is an appropriate broadcast station (A affiliated station), the reception frequency is switched to that broadcast station.

[0028]

As described above, according to the present invention, it is possible to provide an on-vehicle receiving apparatus capable of appropriately performing a network follow with one tuner.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a vehicle-mounted receiving device according to an embodiment of the present invention.

FIG. 2 is a flowchart of a process performed by a control unit of the vehicle-mounted receiving device according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of a service area and a vehicle position.

FIG. 4 is a diagram showing a network affiliated station.

FIG. 5 is a diagram showing frequency change permission / prohibition time zones.

FIG. 6 is a block diagram showing a configuration of a conventional in-vehicle receiving device.

[Explanation of symbols]

12 ··· tuner, 16 ··· video output unit, 13 ··· PLL circuit, 21
····· GPS receiver, 14 ··· Control unit,
22 ... Broadcasting station database, 15 ...
-Audio output unit, 23---Clock.

Claims (6)

[Claims] 1. A tuner for changing a receiving frequency to receive a broadcast of a desired broadcast station, and when the reception condition is deteriorated, the broadcast of another broadcast station having the same reception condition and broadcasting the same program is improved. In the in-vehicle receiving apparatus having a network follow function for changing to a receiving frequency of the tuner, a position detecting means for detecting a position of a vehicle, and a service area information for each broadcasting station. Service area information storage means, a plurality of broadcast stations broadcasting the same program, network information storage means storing broadcast frequencies corresponding to the broadcast information, network information storage means, a clock means for clocking a current time, and the clock means Control means for controlling so as to prohibit or permit the change of the reception frequency based on a time zone to which the current time counted by the timer belongs. When the control means controls to permit the change of the reception frequency, when the position of the vehicle is out of the service area of the currently receiving broadcast station stored in the service area information storage means, the reception frequency is changed. Changing means for changing to a broadcast frequency of a broadcasting station which broadcasts another identical program stored in the network information storage means and which includes the position of the vehicle in the service area stored in the service area information storage means. An in-vehicle receiver characterized by the above-mentioned. 2. A broadcasting station that broadcasts the same program, wherein the position of the vehicle detected by the position detecting means is outside the service area of the currently receiving broadcasting station, and the position of the vehicle is included in the service area. 2. The in-vehicle receiving device according to claim 1, further comprising a second changing unit that changes the reception frequency to a broadcast frequency of a receivable broadcasting station when the reception frequency does not exist. 3. The control means, even in a time zone in which the change of the reception frequency is prohibited, permits the change of the reception frequency when the reception state of the currently receiving broadcast is extremely deteriorated. The in-vehicle receiving device according to claim 1, wherein: 4. The control means determines whether the change of the reception frequency is prohibited or permitted based on an identification signal for identifying whether the received program is a network program or a local program included in a broadcast wave. The in-vehicle receiving device according to claim 1, wherein: 5. The apparatus according to claim 1, wherein the control means determines whether or not to prohibit or permit the change of the reception frequency based on the prohibition time zone information stored in the memory by a manual operation. In-vehicle receiver. 6. The control means is extracted from a broadcast wave,
2. The in-vehicle receiving device according to claim 1, wherein it is determined whether the change of the reception frequency is prohibited or permitted based on the prohibition time zone information stored in the memory.