WO2006098108A1

WO2006098108A1 - Receiving apparatus

Info

Publication number: WO2006098108A1
Application number: PCT/JP2006/302523
Authority: WO
Inventors: Shunsuke Konno; Akikazu Kobayashi; Takao Matsumoto
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2005-03-17
Filing date: 2006-02-14
Publication date: 2006-09-21
Also published as: JP2006262126A

Abstract

A receiving apparatus (10) comprises an HDTV wave receiver (11) for receiving terrestrial digital HDTV broadcast waves; a one-segment wave receiver (12) for receiving one-segment broadcast waves; an analog wave receiver (13) for receiving terrestrial analog broadcast waves; a vehicle speed sensor (14) for detecting the movement speed of a vehicle; a geographic data storage part (15) for storing geographic data; a current position detecting part (16) for detecting a current position of the vehicle; a reception area acquiring/determining part (17) for acquiring the reception area information of each broadcast wave to determine a receivable broadcast wave; a broadcast wave deciding part (18) for deciding, based on the movement speed and the determination result, a broadcast wave to be received; a receiver selection part (20) for selecting a receiver; and an image/sound output part (21) for outputting images and sounds. In this way, a receiving apparatus can be provided which, even if mounted on a mobile unit, can select a broadcast wave that can provide stable displayed images on a display device.

Description

Specification

Receiver

Technical field

The present invention relates to a receiving device that receives, for example, a digital broadcast wave or an analog broadcast wave.

Background art

Conventionally, as this type of receiving apparatus, the following is known. A conventional receiving apparatus includes a digital broadcast tuner that receives a digital broadcast wave, a frequency selection circuit that selects a frequency of the digital broadcast, an analog broadcast tuner that receives an analog broadcast wave, and a digital broadcast tuner or an analog broadcast tuner. And a display for displaying an image of the selected broadcast wave, so that a digital broadcast program or an analog broadcast program can be viewed (see, for example, JP-A-10-79935).

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Disclosure of the invention

Problems to be solved by the invention

[0003] However, in a conventional receiving device, when mounted on a moving body such as a vehicle, the analog broadcast wave and the digital broadcast wave are reduced when the vehicle is stopped and moving! It is not possible to detect whether this is receivable. As a result, depending on the position of the vehicle, the video displayed on the display may be frozen or interrupted. In other words, there was a problem that the video of the broadcast program could not be displayed stably and visually.

[0004] The present invention has been made to solve such problems, and even when mounted on a mobile object, a broadcast wave that can provide a display image more stable than the conventional one can be selected. An object is to provide a receiving apparatus.

Means for solving the problem

[0005] A receiving apparatus of the present invention includes a current position detecting unit that detects a current position of a moving body, a speed detecting unit that detects a moving speed of the moving body, and a plurality of radio waves that respectively receive a plurality of broadcast waves. Based on the transmission / reception unit, reception area information for multiple broadcast waves at the current position and reception receivable to determine receivable broadcast wave Z determination unit, moving speed and determination result! / ヽAnd a reception selection unit that selects one of a plurality of broadcast wave reception units.

[0006] The reception area acquisition Z determination unit further sets the priority of a plurality of broadcast waves based on the reception area information.

[0007] The reception area acquisition Z determination unit further detects the reception status of a plurality of broadcast waves, and the reception selection unit selects any one of the plurality of broadcast wave reception units based on the reception status. Have a success.

[0008] Further, the reception area acquisition Z determination unit updates the reception area information based on the reception status.

[0009] Furthermore, the receiving device of the present invention generates a signal indicating that the current position is included in the reception limit area when the current position is included in a predetermined reception limit area of a plurality of broadcast waves. It may have a configuration including a display signal generation unit.

The invention's effect

[0010] Since the present invention selects any of the plurality of broadcast waves based on the moving speed of the mobile object and the reception area information of the plurality of broadcast waves, even when mounted on the mobile object, the present invention is more than the conventional one. It is possible to provide a receiving apparatus having an effect that a broadcast wave that can provide a stable display image can be detected and displayed on a display.

Brief Description of Drawings

FIG. 1 is a block diagram showing a configuration of receiving apparatus 10 according to the first embodiment of the present invention.

2 is a flowchart showing processing of the receiving device 10 shown in FIG.

[FIG. 3] FIG. 3 is a flowchart showing a detailed process of receiving area determination of the receiving apparatus 10 of FIG.

[FIG. 4] FIG. 4 is a flowchart showing a detailed process of determining a broadcast wave by the receiving apparatus 10 of FIG.

FIG. 5 is a block diagram showing a configuration of receiving apparatus 30 according to the second embodiment of the present invention.

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It is.

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[Fig. 6] FIG. 6 is a flowchart showing the detailed processing of the reception area determination of the reception device 30 of FIG.

FIG. 7 is a block diagram showing a configuration of receiving apparatus 50 according to the third embodiment of the present invention.

[FIG. 8] FIG. 8 is a flowchart showing a detailed process of receiving area determination of the receiving device 50 of FIG.

[FIG. 9] FIG. 9 is a flowchart showing detailed processing of broadcast wave determination of the receiving device 50 of FIG.

Explanation of symbols

30, 50 Receiver

11 HDTV wave receiver

12 1 segment wave receiver

13 Analog wave receiver

14 Vehicle speed sensor

15 Map data storage

16 Current position detector

17, 37, 57 Receive area acquisition Z judgment part

18, 38, 58 Broadcast wave decision section

19 memory

20 Receiver selector

21 Video / audio output section

59 Area display signal generator

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The receiving device of the present invention is mounted on a vehicle, and a terrestrial digital HDTV (High Definition Television) broadcast wave, a terrestrial digital one-segment broadcast wave (hereinafter simply referred to as “one-segment broadcast wave”), and a terrestrial analog broadcast wave. An example of receiving and will be described. [0014] (First embodiment)

First, the configuration of the receiving apparatus according to the first embodiment of the present invention will be described.

[0015] As shown in FIG. 1, the receiving apparatus 10 of the present embodiment includes an HDTV wave receiver 11 that receives a terrestrial digital HDTV broadcast wave, a 1-segment wave receiver 12 that receives a 1-segment broadcast wave, Analog wave receiver 13 that receives analog terrestrial broadcast waves, vehicle speed sensor 14 that detects the moving speed of the vehicle, map data storage unit 15 that stores map data including reception area information for each broadcast wave, and the current vehicle state Based on the moving speed and the reception area information, the current position detection unit 16 that detects the position, the reception area information that acquires the reception area information of each broadcast wave, and the reception area acquisition Z determination unit 17 that determines the receivable broadcast wave. A broadcast wave determination unit 18 that determines broadcast waves, a memory 19 that stores data related to the determination of broadcast waves, a receiver selection unit 20 that selects receivers, and a video and audio output unit 21 that outputs video and audio And has

[0016] The HDTV wave receiver 11 includes an antenna that receives an OFDM (Orthogonal Frequency Division Multiplexing) signal in the UHF (Ultra High Frequency) band, a tuner circuit, an OFDM demodulation circuit, and the like, and receives signals received by the antenna and the tuner. Demodulate and output terrestrial digital HDTV broadcast video and audio signals. The terrestrial digital HDTV broadcast wave is composed of 12 segments, of which the bandwidth of 5.57 MHz, which is equivalent to one channel of terrestrial analog broadcasting, is divided into 13 segments.

[0017] The 1-segment wave receiver 12 includes an antenna, a tuner circuit, an OFDM demodulation circuit, and the like that receive an OFDM signal in the UHF band, demodulates the signal received by the antenna and the tuner, and a 1-segment broadcast video signal and audio Output a signal. The 1-segment broadcast wave is composed of one segment of which the bandwidth of 5.57MHz is divided into 13 segments, and the bandwidth is 428.57kHz.

The analog wave receiver 13 is composed of, for example, an antenna that receives a radio signal in the UHF band, a tuner circuit, a demodulation circuit, and the like, and outputs a terrestrial analog broadcast video signal and audio signal.

Note that the HDTV wave receiver 11, the one-segment wave receiver 12, and the analog wave receiver 13 are examples of a plurality of broadcast wave receiving units. [0020] The vehicle speed sensor 14 is an example of a speed detection unit. For example, the vehicle speed sensor 14 receives a pulse generation circuit force pulse signal that generates a pulse signal corresponding to the traveling speed of the vehicle, and moves the vehicle based on the received pulse signal. Detect speed. Alternatively, the vehicle speed sensor 14 may detect the moving speed of the vehicle by accumulating the acceleration along the traveling direction of the vehicle obtained by the acceleration sensor force mounted on the vehicle.

[0021] The map data storage unit 15 is composed of, for example, a node disk drive, and stores map data including reception area information of each broadcast wave.

[0022] Here, the reception area information refers to information that represents an area in which terrestrial digital HDTV broadcast waves, one-segment broadcast waves, and terrestrial analog broadcast waves can be received, for example, by longitude and latitude. This reception area information is created based on the electric field strength of each broadcast wave measured in advance.

Hereinafter, a specific method for creating the reception area information will be described. First, a vehicle equipped with a plurality of antennas capable of receiving the above-mentioned radio waves is prepared. Each broadcast wave is received in such a state that the vehicle is stopped, and an area where the electric field intensity exceeding the reference value is obtained is approximately represented by a circle for each broadcast wave. With respect to such a circular area, the latitude and longitude data of the center position and the radius data are stored in the map data storage unit 15 as reception area information of each broadcast wave. In the receiving apparatus 10, this area is regarded as a receivable area, and the area outside this area is regarded as an unreceivable area.

[0024] When the areas of the receivable areas as described above are summed for each broadcast wave, the receivable areas increase in the order of terrestrial digital HD TV broadcast waves, 1-segment broadcast waves, and terrestrial analog broadcast waves. Therefore, one-segment broadcast waves can be received within an area where digital terrestrial HDTV waves can be received, and terrestrial analog broadcast waves can also be received within an area where one-segment broadcast waves can be received.

[0025] Even in the receivable area, an area that is in the shadow of a building or mountain and cannot obtain an electric field strength equal to or higher than the reference value is approximately represented as a non-receivable area, for example, by a circle. For the circle representing such an unreceivable area, the latitude and longitude data of the center position and the radius data may be stored in the map data storage unit 15 as unreceivable area information. [0026] The current position detection unit 16 is configured by, for example, a GPS (Global Positioning System) reception unit, and detects the latitude and longitude of the current position of the vehicle based on the received radio wave from the GPS.

[0027] The reception area acquisition Z determination unit 17 includes, for example, a CPU that performs arithmetic processing, a ROM that stores a program executed by the CPU, and a RAM that stores temporary data generated when the CPU performs arithmetic processing. From the map data stored in the map data storage unit 15 to obtain the reception area information of each broadcast wave at the current position of the vehicle, determine the receivable broadcast wave, and set the priority of the broadcast wave. Set. The reception area acquisition Z determination unit 17 further creates a receivable broadcast wave table in which receivable broadcast waves are associated with priorities, and stores them in the memory 19.

[0028] Specifically, the reception area acquisition Z determination unit 17 determines the maximum and minimum values of the latitude and longitude of the receivable area of each broadcast wave constituting the acquired reception area information, and the current position. Compare latitude and longitude. Next, the reception area acquisition Z determination unit 17 determines a receivable broadcast wave based on whether or not the current position is included in the receivable area of each broadcast wave, and sets the priority of the receivable broadcast wave. For example, when all of the terrestrial digital HDTV broadcast wave, 1-segment broadcast wave, and analog terrestrial broadcast wave can be received at the current position, the terrestrial digital HDTV broadcast wave has the best image quality. Is set to 3, the priority of 1 segment broadcast wave is set to 2, and the priority of terrestrial analog broadcast wave is set to 1.

[0029] The broadcast wave determination unit 18 includes a CPU that performs arithmetic processing, a ROM that stores a program executed by the CPU, and a RAM that stores temporary data generated when the CPU performs arithmetic processing. By referring to the data of the receivable broadcast wave table stored in the memory 19, and based on the priority of each broadcast wave and the moving speed of the vehicle, the digital terrestrial HDTV broadcast wave, the 1-segment broadcast wave and the analog terrestrial broadcast wave A broadcast wave that can be received from among them is determined, and a control signal for instructing to select a receiver that can receive the determined broadcast wave is output to the receiver selection unit 20.

[0030] Specifically, the broadcast wave determination unit 18 receives a terrestrial digital HDTV broadcast wave when the vehicle is parked, for example, in an area where the terrestrial digital HDTV broadcast wave can be received. It is determined as a broadcast wave that can be transmitted, and when a vehicle moves, it is determined as a broadcast wave that can receive a one-segment broadcast wave. This is because the 1-segment broadcast wave has a smaller occupied bandwidth than the terrestrial digital HDTV broadcast wave, and is therefore less susceptible to the moving speed of the vehicle.

The memory 19 is composed of, for example, a semiconductor memory, and stores data of a receivable broadcast wave table created by the reception area acquisition Z determination unit 17.

[0032] Based on the control signal output from the broadcast wave determination unit 18, the receiver selection unit 20 selects one of the HDTV V-wave receiver 11, the 1-segment wave receiver 12, and the analog wave receiver 13. select.

[0033] The video / audio output unit 21 includes, for example, a video signal processing circuit, a liquid crystal display, an audio amplification circuit, a speaker, and the like, and outputs video and audio by each broadcast wave.

Next, the operation of receiving apparatus 10 of the present embodiment will be described using FIG.

First, the current position detector 16 receives GPS radio waves and acquires latitude and longitude data of the current position of the vehicle (step S 11).

Next, the map data including the reception area information of each broadcast wave is read from the map data storage unit 15 by the reception area acquisition Z determination unit 17 (step S12).

[0037] Further, the reception area acquisition Z determination unit 17 performs a reception area determination process described later (step S13).

Subsequently, the broadcast wave determination unit 18 executes broadcast wave determination processing (step S14), and a control signal instructing selection of the receiver is output to the receiver selection unit 20.

[0039] Next, the receiver selection unit 20 selects the receiver specified by the input control signal from the HDTV wave receiver 11, the 1-segment wave receiver 12, and the analog wave receiver 13 ( In step S15), the video signal and audio signal demodulated by the selected receiver are output to the video / audio output unit 21.

[0040] After that, the video and audio output unit 21 outputs video and audio (step S16).

[0041] Next, the reception area determination process executed by the reception area acquisition Z determination unit 17 will be described with reference to FIG. In FIG. 3, the terrestrial digital HDTV broadcast wave, 1-segment broadcast wave, and terrestrial analog broadcast wave are respectively represented as HDTV wave, 1-segment wave, and It is abbreviated as “nalog wave”.

[0042] First, it is determined whether or not the current position of the vehicle is within an area where terrestrial digital HDTV broadcast waves can be received (step S21). For example, the latitude and longitude of the terrestrial digital HDTV broadcast wave receivable area is compared with the latitude and longitude of the current position, and it is determined by whether or not the current position is included in the receivable area of each broadcast wave. .

[0043] If it is determined in step S21 that the current position is within an area where terrestrial digital HDTV broadcast waves can be received, the terrestrial digital HDTV broadcast wave having the highest image quality has the highest priority 3. The priority of the 1-segment broadcast wave is set to 2, and the priority of the terrestrial analog broadcast wave is set to 1 (step S22). After these priority data are stored in the memory 19 as receivable broadcast wave table data, the process proceeds to step S14 (see FIG. 2).

[0044] On the other hand, if it is determined that the current position is not within the terrestrial digital HDTV broadcast wave reception area, the current position is in the one-segment broadcast wave reception area. Based on whether or not the power is included, it is determined whether or not the current position is within an area where a 1-segment broadcast wave can be received (step S23).

[0045] If it is determined in step S23 that the current position is within the reception area of the one-segment broadcast wave, the priority of the one-segment broadcast wave is 2, the priority of the terrestrial analog broadcast wave is 1, The priority of the digital HDTV broadcast wave is set to 0 (step S24). After these priority data are stored in the memory 19 as receivable broadcast wave table data, the process proceeds to step S 14 (see FIG. 2).

[0046] On the other hand, if it is not determined in step S23 that the current position is within the reception area of the 1-segment broadcast wave, the priority of the terrestrial analog broadcast wave is 1, the 1-segment broadcast wave, and the terrestrial digital HDTV broadcast wave. Is set to 0 (step S 25), and these priority data are stored in the memory 19 as data of the receivable broadcast wave table. Then, the process proceeds to step S 14 (see FIG. 2). .

Next, the broadcast wave determination process (step S14 in FIG. 2) executed by the broadcast wave determination unit 18 will be described with reference to FIG. In Fig. 4, one segment broadcast wave is abbreviated as one segment wave. [0048] First, the data of the receivable broadcast wave table is read from the memory 19, there is a broadcast wave with a priority set to 3, and the moving speed of the vehicle is a predetermined reference speed, for example, every hour It is determined whether or not the force exceeds 5 km (step S31).

[0049] If it is determined in step S31 that there is a broadcast wave with priority set to 3 and the moving speed of the vehicle exceeds the reference speed, the broadcast wave to be received is a one-segment broadcast wave. Once determined (step S32), a control signal instructing selection of the one-segment wave receiver 12 is transmitted to the receiver selection unit 20, and then step S15 (see FIG. 2) is performed. In other words, if the vehicle moves at a speed exceeding the reference speed in an area where all of the terrestrial digital HDTV broadcast wave, 1-segment broadcast wave and analog terrestrial broadcast wave can be received, the terrestrial digital HDTV broadcast One segment broadcast wave, which is less affected by the moving speed than the wave, is selected.

[0050] On the other hand, if it is determined in step S31 that there is no broadcast wave with the priority set to 3 or the moving speed of the vehicle is equal to or lower than the reference speed, the broadcast wave to be received has the highest priority. The set broadcast wave is determined (step S33), and a control signal instructing selection of a receiver that receives the corresponding broadcast wave is transmitted to the receiver selection unit 20, and then step S15 (see FIG. 2) is performed. . That is, the control signal instructing the selection of the 1-segment wave receiver 12 is selected in the area where the 1-segment broadcast wave can be received, and the analog wave receiver 13 is selected in the area where the 1-segment broadcast wave cannot be received. Is sent to the receiver selection unit 20.

[0051] As described above, according to the receiving device 10, the reception area acquisition Z determination unit 17 acquires the reception area information of each broadcast wave, and generates a broadcast wave that can be received at the current position of the vehicle. judge . The broadcast wave determination unit 18 determines a broadcast wave to be received based on the moving speed of the vehicle and the reception area information. Furthermore, the receiver selection unit 20 selects a receiver that can receive the selected broadcast wave. As a result, even when the receiver 10 is mounted on a vehicle, it is possible to select a broadcast wave that allows the video / audio output unit 21 to display a display image that is more stable than the conventional one.

[0052] In the above-described embodiment, the example in which the receiving device 10 is mounted on the vehicle has been described. However, the present invention is not limited to this, and the configuration is mounted on a moving body. If so, the same effect can be obtained. Note that the moving body in this embodiment refers to any of an automobile, a two-wheeled vehicle, a ship, an aircraft, a railway vehicle, and a pedestrian. For example, even when a mobile phone equipped with the receiving device 10 can receive a one-segment broadcast wave and a terrestrial analog broadcast wave, such a mobile phone can display video more stably than the conventional one.

Further, in the above-described embodiment, an example is described in which the receiving device 10 receives one of the three types of terrestrial digital HDTV broadcast waves, one-segment broadcast waves, and terrestrial analog broadcast waves. However, the present invention is not limited to this, and the same effect can be obtained as long as it includes a plurality of receivers that respectively receive a plurality of broadcast waves.

[0054] (Second Embodiment)

First, the configuration of the receiving apparatus according to the second embodiment of the present invention will be described.

[0055] As shown in FIG. 5, when compared with the receiving device 10 of the first embodiment, the receiving device 30 of the present embodiment replaces the reception area acquisition Z determination unit 17 with each broadcast wave. The difference is that a reception / rear acquisition Z determination unit 37 that determines reception broadcast information by receiving area information is provided. Since the configuration other than the reception area determination unit 37 in the receiving device 30 is the same as the configuration of the receiving device 10, in FIG. 5, the components corresponding to the configuration in FIG. Omitted.

The reception area acquisition Z determination unit 37 has the same configuration as the reception area acquisition Z determination unit 17 described above, and performs the same processing as the reception area acquisition Z determination unit 17. In addition to this processing, the reception area acquisition Z determination unit 37 is different from the reception area acquisition Z determination unit 17 described above in that it performs the following additional processing. As an additional process, the reception area determination unit 37 includes a signal indicating the reception status of the HDTV wave receiver 11, data on the moving speed output from the vehicle speed sensor 14, and data on the latitude and longitude of the current position of the vehicle. Based on the above, the map data stored in the map data storage unit 15 is updated. Here, the reception status of the HDTV wave receiver 11 means, for example, a reception error rate obtained as a result of demodulating an OFDM signal in an OFDM demodulation circuit.

[0057] Specifically, taking the case where the vehicle is stopped as an example, in the map data read from the map data storage unit 15, the terrestrial digital HDTV broadcast wave receivable area When the current position of the vehicle is included in the circle indicating, the reception area acquisition Z determination unit 37 receives the signal indicating the reception error rate equal to or higher than a predetermined threshold from the HD TV wave receiver 11, and The area within the circle that includes the current location of the terrestrial digital HDTV broadcast wave is updated from the receivable area of the terrestrial digital HDTV broadcast wave as the one-segment broadcast wave receivable area and stored in the map data storage unit 15.

Next, the operation of receiving apparatus 30 of the present embodiment will be described using FIG. Note that the operation of the receiving device 30 is different from the operation of the receiving device 10 described above only in the reception area determination processing executed by the reception area acquisition Z determination unit 37, and thus the description of the other operations is omitted. Further, in the steps shown in FIG. 6, the same reference numerals are given to the same processing as the reception area determination processing (see FIG. 3) of the receiving device 10, and the description thereof is omitted.

[0059] First, in step S21, if it is determined that the current position is within the terrestrial digital HDTV broadcast wave receivable area, the reception error rate is equal to or higher than a predetermined reference rate, and the vehicle is moved. It is determined whether or not the speed is a predetermined reference speed (step S41). Here, the above-mentioned reference rate is a value that serves as a reference for whether there are many reception errors of terrestrial digital HDTV broadcast waves, and is set to 80%, for example. The reference speed is a reference value for determining whether or not the vehicle is stationary, and is set to, for example, OkmZh.

[0060] In step S41, when it is determined that the reception error rate is equal to or higher than the reference rate and the moving speed of the vehicle is the reference speed, the priority of the one-segment broadcast wave is set to 2, The priority of the analog broadcast wave is set to 1, and the area within the circle that includes the current position of the vehicle is updated from the receivable area of the terrestrial digital HDTV broadcast wave to the receivable area of the 1-segment broadcast wave ( Step S42). The set priority data is stored in the memory 19 as receivable broadcast wave table data, and the updated data is stored as map data.

[0061] On the other hand, if it is determined in step S41 that the reception error rate of the terrestrial digital HDTV broadcast wave is less than the reference rate, or the moving speed of the vehicle is not the reference speed, the terrestrial digital HDTV The priority of the broadcast wave is set to 3, the priority of the one-segment broadcast wave is set to 2, and the priority of the terrestrial analog broadcast wave is set to 1 (step S43). The set priority data is stored in the memory 39 as data of the receivable broadcast wave table. [0062] It should be noted that the processing after step S21 when the current position is not determined to be within the terrestrial digital HDTV broadcast wave receivable area is the receiving apparatus according to the first embodiment. Since this is the same as the reception area determination process in FIG.

[0063] As described above, according to the receiving device 30 of the present embodiment, the reception area acquisition Z determination unit 37 updates the reception area information based on the reception status and the moving speed of the vehicle. Therefore, even if the reception area information set in the past changes due to changes in the transmission environment due to changes in the position of the transmission antenna or transmission power, or changes in the reception environment due to construction or dismantling of the building, etc. Since the device 30 determines a broadcast wave to be received based on the reception area information updated as described above, it is possible to select a broadcast wave that provides a more stable display image than the conventional one.

In the above-described embodiment, the reception area acquisition Z determination unit 37 has been described with an example of a configuration in which a signal indicating a reception error rate is input from the HDTV wave receiver 11. The embodiment is not limited to this. The reception area acquisition Z determination unit 37 inputs a signal indicating the reception error rate from either the HDTV wave receiver 11 or the 1-segment wave receiver 12. The same effect can be obtained with the configuration.

[0065] (Third embodiment)

First, the configuration of the receiving apparatus according to the third embodiment of the present invention will be described.

[0066] As shown in FIG. 7, the receiving device 50 of the present embodiment is replaced with a reception area acquisition Z determination unit 17 and a broadcast wave determination unit 18 as compared with the receiving device 10 according to the first embodiment. The reception area acquisition Z determination unit 57 and the broadcast wave determination unit 58 are different from the reception area acquisition Z determination unit 57 and the area display signal generation unit 59. The configuration other than the above is the same as the configuration of the receiving apparatus 10. Therefore, in FIG. 7, the same reference numerals are assigned to the components corresponding to the configuration of FIG. 1, and the description of the components corresponding to the configuration of FIG. 1 is omitted.

The reception area acquisition Z determination unit 57 has the same configuration as the reception area acquisition Z determination unit 17 described above, and performs the same processing as the reception area acquisition Z determination unit 17. However, the reception area acquisition Z determination unit 57 is different from the reception area acquisition Z determination unit 17 described above in that it performs the following additional processing. As an additional process, the reception area determination unit 57 first compares the map data read from the map data storage unit 15 with the latitude and longitude data of the current position of the vehicle. Then, it is determined whether or not the current position of the vehicle is included in the reception limit area. As a result of this determination, if the current position of the vehicle is included in the reception limit area, the reception area acquisition z determination unit 57 describes in the receivable broadcast wave table that the vehicle is in the reception limit area. Here, the reception limit area is a boundary portion between the receivable area and the unreceivable area for each broadcast wave.

[0068] Specifically, the reception area acquisition Z determination unit 57 compares the latitude and longitude of the boundary of the receivable area of a certain broadcast wave with the latitude and longitude of the current position of the vehicle. If the difference between latitudes and the difference between longitudes are within 1 degree, for example, the reception area acquisition Z determination unit 57 determines that there is a vehicle in the reception limit area of the broadcast wave, and the vehicle in the reception limit area. Information that both are present (hereinafter referred to as “reception boundary information”) is described in the receivable broadcast wave table for the broadcast wave. The above process is executed for all the radio waves that can be received by the receiving device 50.

Broadcast wave determination unit 58 has a configuration similar to that of broadcast wave determination unit 18 described above, performs processing similar to that of broadcast wave determination unit 18, and receives a control signal similar to that described above as a receiver selection unit. Output to 60. The broadcast wave determining unit 58 is different from the above-described broadcast wave determining unit 18 in that it further performs the following additional processing. As an additional process, the broadcast wave determination unit 58 receives signals indicating the reception status from the HDTV wave receiver 11 and the one-segment wave receiver 12, respectively. Here, the reception status refers to the reception error rate obtained as a result of demodulation of the OFDM signal, as in the second embodiment.

[0070] Further, the broadcast wave determination unit 58 receives a control signal for generating an error video based on the signal indicating the reception status and the reception boundary information described in the receivable broadcast wave table. Output to the selection unit 20. Here, the error video is, for example, a video composed of white noise in order to display the reception boundary information on the display of the video / audio output unit 21.

[0071] The region display signal generation unit 59 includes, for example, an oscillation circuit that generates white noise.

Next, the operation of receiving apparatus 50 will be described. Note that the operation of the receiving device 50 is different from the operation of the receiving device 10 according to the first embodiment only in the reception area determination process and the broadcast wave determination process, and thus description of other operations is omitted. First, the reception area determination process executed by the reception area acquisition Z determination unit 57 will be described with reference to FIG. In FIG. 8, the same steps as those in the reception area determination process (see FIG. 3) of the receiving apparatus 10 are denoted by the same reference numerals, and description thereof is omitted. In addition, in Fig. 8, the reception limit area is simply expressed as a boundary.

[0074] First, it is determined whether or not the current position of the vehicle is within the reception limit area of any broadcast wave receivable area (step S51).

[0075] If it is not determined in step S51 that the current position of the vehicle is within the reception limit area of any broadcast wave receivable area, in the reception area determination process (see Fig. 3) of the reception device 10 Processing similar to that in steps S21 to S25 is performed.

[0076] On the other hand, if it is determined in step S51 that the current position of the vehicle is within the reception limit area of any broadcast wave reception area, the reception limit area of the corresponding broadcast wave is the digital terrestrial HDTV broadcast. It is determined whether or not it is within the wave reception limit area (step S5

2). Here, if the reception limit area of the corresponding broadcast wave is determined to be the reception limit area of the terrestrial digital HDTV broadcast wave, the reception limit area information indicating that it is the reception limit area of the terrestrial digital HDTV broadcast wave can be received. Described in the wave table (step S5

3) After that, step S23 is performed.

[0077] On the other hand, in step S52, if the reception limit area of the corresponding broadcast wave is not determined to be the reception limit area of the terrestrial digital HDTV broadcast wave, the reception limit area of the corresponding broadcast wave is one segment broadcast wave. It is judged whether or not the reception limit area power is low (step S5

Four). Here, if the reception limit area of the corresponding broadcast wave is determined to be the reception limit area of the one-segment broadcast wave, the reception limit area information indicating that it is the reception limit area of the one-segment broadcast wave is the receivable broadcast wave. It is described in the table (step S55), and then step S25 is performed.

On the other hand, if it is determined in step S54 that the corresponding broadcast wave reception limit area is not determined to be the one-segment broadcast wave reception limit area, step S24 is performed.

Next, the broadcast wave determination process executed by the broadcast wave determination unit 58 will be described with reference to FIG. In FIG. 9, the reception limit area is simply expressed as a boundary.

First, the data of the receivable broadcast wave table is read from the memory 19, and the current position is It is determined whether or not a reception error occurs in the terrestrial digital HDTV wave reception limit area (step S61). A reception error has occurred when the reception error rate is above the threshold! Uh.

[0081] In step S61, if it is determined that the current position is within the reception limit area of the terrestrial digital HDTV broadcast wave and that a reception error has occurred, a control signal for displaying an error video is received. The receiver selection unit 20 obtains an error video representing white noise from the area display signal generation unit 59 and outputs it to the video / audio output unit 21. As a result, the error video is displayed on the video / audio output unit 21 for several seconds, for example (step S62). Then, the broadcast wave to be received is determined as a one-segment broadcast wave (step S63), and the video and audio of the one-segment broadcast wave are output from the video / audio output unit 21.

[0082] On the other hand, if it is determined in step S61 that the current position is not within the reception limit area of the terrestrial digital HDTV broadcast wave or that no reception error has occurred, the current position is set to 1. It is determined whether or not there is a segment broadcast wave reception limit area and a reception error has occurred (step S64).

If it is determined in step S64 that the current position is in the reception limit area of the one-segment broadcast wave and a reception error has occurred, the process proceeds to step S63.

[0084] On the other hand, if it is determined in step S64 that the current position falls within the reception limit area of the one-segment broadcast wave or that no reception error has occurred, a control signal for displaying an error video is received by the receiver. It is output to the selection unit 20. Also in this case, an error screen is displayed by the video / audio output unit 21 for several seconds, for example, as in step S62 (step S65). The broadcast wave to be received is determined to be a terrestrial analog broadcast wave (step S66), and the video and audio of the terrestrial analog broadcast wave are output from the video / audio output unit 21.

As described above, according to receiving apparatus 50 of the present embodiment, reception area acquisition Z determination unit 57 acquires reception limit area information and describes it in the receivable broadcast wave table, and broadcast wave determination unit 58 outputs a control signal for displaying an error video to the receiver selection unit 20 based on the signal indicating the reception status and the reception limit area information described in the receivable broadcast wave table. Further, the receiver selection unit 20 causes the video / audio output unit 21 to display the error video output from the area display signal generation unit 59 in accordance with the control signal for error video display. With the above configuration, the user is notified that the vehicle is in the reception limit area of the broadcast wave being received, and the broadcast wave that can be received more stably than the broadcast wave is displayed on the video / audio output unit 21. Can do.

In the above-described embodiment, the example has been described in which the area display signal generation unit 59 generates white noise in order to represent the information that the vehicle is present in the reception limit area. The region display signal generation unit 59 is not limited to this, and the same effect can be obtained even when it is configured to generate a signal such as a blue still image or a warning sound. Industrial applicability

[0087] As described above, the receiving apparatus according to the present invention can detect and display a broadcast wave that provides a more stable display image than the conventional one even when mounted on a mobile object. It has an effect and is useful as a receiver for receiving digital broadcast waves and analog broadcast waves.

Claims

The scope of the claims

[1] A current position detection unit that detects a current position of a moving body, a speed detection unit that detects a moving speed of the moving body, a plurality of broadcast wave reception units that respectively receive a plurality of broadcast waves, and the current position detection unit A reception area acquisition Z determination unit that acquires reception area information of the plurality of broadcast waves at a location and determines receivable broadcast waves, and the plurality of broadcasts based on the moving speed and the determination result. A reception device comprising: a wave selection unit for selecting one of!

[2] The receiving apparatus according to [1], wherein the reception area acquisition Z determination unit further sets priorities of the plurality of broadcast waves based on the acquired reception area information.

[3] The reception area acquisition Z determining unit further detects the reception status of the plurality of broadcast waves, and the reception selection unit is based on the reception status! The receiving device according to claim 1, wherein one of them is selected.

[4] The receiving apparatus according to claim 3, wherein the first-term reception area acquisition Z determination unit updates the reception area information based on the reception status.

[5] When the current position is included in a predetermined reception limit area of the plurality of broadcast waves

The receiving apparatus according to claim 1, further comprising a region display signal generating unit that generates a signal indicating that the current position is included in the reception limit area.