JP2012099892A - Receiver and receiving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a receiver which is capable of switching a channel to a program in a traveling destination region without interrupting a viewing program.SOLUTION: When a predetermined time passes after the receiving state of broadcasting radio waves becomes defective, plural reception systems are divided into systems for channel scanning and systems for program reception, and channel scanning is performed by the systems for channel scanning while receiving a program by the systems for program reception. In a case where a channel of a relay station cannot be found by channel scanning processing, a first predetermined time is set as the predetermined time. In a case where the receiving quality of a channel being received by the systems for program reception is maximum though the channel of the relay station is found, a second predetermined time shorter than the first predetermined time is set as the predetermined time.

Description

  The present invention relates to a receiving apparatus and a receiving method for receiving broadcasts and communications, and more particularly to a receiving apparatus and a receiving method that are mounted on a mobile body and receive terrestrial digital broadcasting while moving.

  A receiving device that receives a digital broadcast mounted on a moving body such as an automobile changes the channel that can be received when moving from the current location to another region. It is necessary to scan the channel and reset the receivable channel in the destination area.

  However, when the user scans the channel by operating the remote controller, there is a problem that the program cannot be viewed during that time. In order to solve this problem, for example, in Patent Document 1, a main tuner for receiving a program and a sub-tuner for executing a channel scan are provided, and the sub-tuner scans all frequencies to increase the reception intensity of each frequency. Channel scanning is shortened by detecting and making it possible to receive channels whose reception intensity is greater than or equal to a threshold, and allowing only the main tuner to scan these channels.

JP 2006-13945 A

  However, the method of Patent Document 1 has an advantage that channels that can be received by the sub-tuner can be scanned while viewing the program, but since the channel scan for updating channel information is finally performed by the main tuner, There is a problem that program viewing is interrupted.

The present invention has been devised in view of the above problems, and an object of the present invention is to provide a receiving apparatus and a receiving method capable of switching channels to a program in a destination area without interrupting a viewing program. It is in.
A further object is that a tuner that performs channel scanning can be used as a program viewing tuner while channel scanning is not being performed, and the number of times channel scanning is performed is low, and a tuner for viewing programs during channel scanning. It is an object of the present invention to provide a receiving apparatus and a receiving method capable of reducing the influence that the reception performance is deteriorated due to the decrease in the number.

In order to achieve the above object, the present invention is a receiving apparatus for receiving a broadcast signal, and controls a plurality of receiving systems for receiving a broadcast signal and selecting a predetermined channel, and receiving operations of the plurality of receiving systems. And a control unit that
If the reception state of the broadcast radio wave is good, the control unit selects and synthesizes the same channel to perform the program reception process, and when the reception state of the broadcast radio wave becomes poor and a predetermined time elapses. The control unit divides the plurality of reception systems into program reception and channel scan, the program reception reception system continues program reception, and the channel scan reception system has the same content as the viewing program. Channel control processing is performed to search for a channel that broadcasts, and the control unit determines that the predetermined time is set to the first time when a channel that broadcasts the same content in addition to the viewing program is not found in the channel scanning processing. In addition, the control unit broadcasts the same content in addition to the viewing program although the reception quality is lower than the viewing program in the channel scan processing. When able to discover a tunnel is characterized by controlling so as to set the predetermined time to a short second time than the first time.

Further, the present invention is a receiving device for receiving a broadcast signal, a plurality of receiving systems for receiving a broadcast signal and selecting a predetermined channel, a control unit for controlling the receiving operation of the plurality of receiving systems, A speed information acquisition unit that acquires a moving speed at which the receiving device moves;
If the reception state of the broadcast radio wave is good, the control unit selects and synthesizes the same channel to perform the program reception process, and when the reception state of the broadcast radio wave becomes poor and a predetermined time elapses. The control unit divides the plurality of reception systems into program reception and channel scan, the program reception reception system continues program reception, and the channel scan reception system has the same content as the viewing program. Channel control processing is performed to search for a channel that broadcasts, and the control unit determines that the predetermined time is set to the first time when a channel that broadcasts the same content in addition to the viewing program is not found in the channel scanning processing. (= First moving distance / moving speed), and the control unit may watch the channel scan process although the reception quality is lower than the viewing program. When a channel that broadcasts the same content can be found in addition to the set, the predetermined time is set to the second time (= second movement distance / movement speed, first movement distance> second movement distance) It is characterized by controlling to do.

Further, according to the present invention, in the receiving apparatus described above, when the reception state of the broadcast radio wave becomes poor, the program contents of the channels received by the plurality of receiving systems are relatively resistant to errors that occur during transmission. It is characterized by the point in time when a weak weak layer transmission program is switched to a relatively strong strong layer program.
Further, according to the present invention, when the plurality of receiving systems are divided for program reception and channel scanning in the receiving apparatus described above, a receiving system having a good broadcast radio wave reception state is used for program reception, and the remaining receiving systems are channel scanned. It is characterized by being used for.

Further, the present invention is a reception method for receiving a broadcast signal, wherein a reception quality determination step for determining whether or not the reception quality of a viewing program to be received and viewed is within a predetermined range, and the reception quality determination step However, when it is determined that the reception quality is worse than a predetermined range, a timer step that starts counting time, and the reception quality determination step before the time counted in the timer step reaches a predetermined time A channel scanning step of searching for a channel that broadcasts the same content as the viewing program if the reception quality determined in step 1 does not recover to a predetermined range;
In the channel scanning step, the reception quality is inferior to that of the viewing program in the first time when the channel scanning step cannot find a channel that broadcasts the same content in addition to the viewing program. However, when a channel that broadcasts the same content can be found in addition to the viewing program, the second time is set shorter than the first time.

The present invention also relates to a receiving method for a receiving apparatus that receives a broadcast signal, a reception quality determining step for determining whether or not the reception quality of a viewing program to be received and viewed is within a predetermined range, and the reception When the quality determination step determines that the reception quality is worse than a predetermined range, a timer step that starts counting time, and the reception until the time counted in the timer step reaches a predetermined time A channel scanning step for searching for a channel that broadcasts the same content as the viewing program if the reception quality determined in the quality determination step does not recover within a predetermined range; and a speed for acquiring a moving speed at which the receiving device moves An information acquisition step,
In the channel scan step, the channel scan is performed at the first time (= first moving distance / moving speed) when a channel that broadcasts the same content in addition to the viewing program cannot be found. In the step, if a channel that broadcasts the same content can be found in addition to the viewing program, the reception quality is inferior to the viewing program, but the second time (= second movement distance / movement speed, first movement) Distance> second movement distance).

According to the present invention, there is an effect that it is possible to provide a receiving apparatus and a receiving method for switching a channel to a program in a destination area without interrupting a viewing program.
Further, depending on the embodiment, a tuner that performs channel scanning can be used as a program viewing tuner while channel scanning is not being performed, and channel scanning can be performed by performing channel scanning at an appropriate timing. There is an effect that it is possible to provide a receiving apparatus and a receiving method that can reduce the number of times of execution and reduce the influence of a poor reception state at the time of channel scanning.

2 is a block diagram illustrating a configuration of a receiving device 1 according to Embodiment 1. FIG. 3 is a flowchart illustrating a reception operation in the first embodiment. 6 is a flowchart illustrating scan processing according to the first embodiment. It is a figure which shows the receivable area of a 1st broadcast station and a 2nd broadcast station. 10 is a flowchart illustrating scan processing according to the second embodiment. 10 is a flowchart illustrating scan processing according to the third embodiment. 10 is a flowchart illustrating scan processing according to the fourth embodiment. FIG. 10 is a block diagram illustrating a configuration of a receiving device 1 in a fifth embodiment. 14 is a flowchart illustrating scan processing according to the fifth embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the receiving apparatus according to the embodiment of the present invention, a broadcast signal by ISDB-T (Integrated Services Digital Broadcasting for Terrestrial), which is a transmission system of Japanese terrestrial digital broadcasting, is received, and MPEG2-TS (Transport Stream) (hereinafter, referred to as “Transport Stream”). (TS signal) format video / audio signals can be decoded. In ISDB-T, the transmission band of one channel can be divided into 13 segments, and each segment can be combined to perform hierarchical transmission of up to three layers. Currently, using this hierarchical transmission, 12 segments are used for high-quality broadcasting for fixed reception terminals (hereinafter referred to as 12-segment broadcasting), and the remaining one segment is used for portable reception terminals. Low-quality broadcasting (hereinafter referred to as 1Seg broadcasting) is being carried out. The 12-segment broadcasting and the one-segment broadcasting are mainly simulcast broadcasting the same program content. Here, the 12-segment broadcast is a high-quality broadcast with a large transmission capacity, but it is weak in error resistance and cannot be received unless the reception state of the broadcast radio wave is relatively good. On the other hand, one-seg broadcasting is a low-quality broadcasting with a small transmission capacity, but is strong in error resistance and can be received even if the reception state of the broadcast radio wave is relatively poor.

FIG. 1 is a block diagram showing a configuration of a receiving device 1 according to Embodiment 1 of the present invention.
The antenna unit 2a receives the broadcast radio wave transmitted from the broadcast station and supplies it to the channel selection unit 3a. The channel selection unit 3 a selects a desired channel from the supplied broadcast signal according to an instruction from the control unit 8 and supplies the selected channel to the demodulation unit 4. A reception system including the antenna unit 2a and the channel selection unit 3a is defined as a first reception system 10a. The antenna unit 2b and the channel selection unit 2b have the same functions as the antenna unit 2a and the channel selection unit 3a, and a reception system including these functions is a second reception system 10b.

  The demodulation unit 4 performs demodulation processing on each channel signal supplied from the first reception system 10a and the second reception system 10b, and outputs the generated TS signal to the TS analysis unit 5a or the TS analysis unit 5b. . When the TS signal generated from the channel signal of the first reception system 10a is output to the TS analysis unit 5a, the TS signal generated from the channel signal of the second reception system 10b is output to the TS analysis unit 5b, When the TS signal generated from the channel signal of the reception system 10a is output to the TS analysis unit 5b, the TS signal generated from the channel signal of the second reception system 10b is output to the TS analysis unit 5a.

  The demodulator 4 can also perform demodulation processing by synthesizing each channel signal supplied from the first reception system 10a and the second reception system 10b according to an instruction from the control unit 8 (hereinafter referred to as diversity synthesis). demodulation). As a specific diversity combining demodulation method, for example, a maximum ratio combining method is used in which a plurality of OFDM (Orthogonal Frequency Division Multiplexing) subcarriers extracted in the process of demodulating each channel signal are weighted and combined for each subcarrier. To do. Alternatively, a selective combining method of selecting a channel signal with the maximum power and discarding other channel signals, an equal gain combining method of combining each channel signal with the same phase, or the like may be used. When diversity combining demodulation is performed, the generated TS signal is output to the TS analysis unit 5a.

  Further, the demodulator 4 supplies information (hereinafter referred to as reception quality information) indicating whether the reception state of the channel signal obtained during the demodulation process is good or bad to the controller 8. The reception quality information includes, for example, a bit error rate (BER), a TS packet error rate (PER), a TS error flag indicating whether a TS packet has an error, and a reception CNR (Carrier to Noise Ratio). , Received power, synchronization status, and the like. These pieces of information are used by the control unit 8 to control the reception operation. Hereinafter, it is assumed that the larger the reception quality information, the better the reception state, and the smaller the reception quality information, the poor the reception state.

  The TS analysis unit 5a extracts program specific information (PSI: Program Specific Information) and program arrangement information (SI: Service Information) from the input TS signal, and holds each information in a memory. Further, an identifier (PID: Packet Identifier) of a TS packet including video and audio is extracted from the extracted PSI / SI, and the TS signal is filtered by each PID, and the video TS packet and the audio TS packet are input to the decoding unit 6. Output.

  The decoding unit 6 decodes video and audio from the video TS packet and audio TS packet supplied from the TS analysis unit 5 a, and supplies the decoded video and audio to the output unit 7. The decoding unit 6 can simultaneously decode both the 12-segment broadcast video and audio and the one-segment broadcast video and audio, and selects one of the video and audio according to the instruction from the control unit 8 to the output unit 7. Supply.

  Here, whether the control unit 8 selects the video and audio of 12-segment broadcasting or the video and audio of one-segment broadcasting is performed as follows, for example. The control unit 8 repeatedly acquires reception quality information from the demodulation unit 4. When the control unit 8 selects video and audio of 12-segment broadcasting, the BER or PER of 12-segment broadcasting is used for reception quality information, and this value becomes smaller than a predetermined condition (the reception state is Switch to video and audio of 1Seg broadcasting when it becomes defective. In addition, when the control unit 18 selects the video and audio of the one-segment broadcasting, the 12-segment broadcasting is performed when the BER or PER of the 12-segment broadcasting becomes larger than a predetermined condition (when the reception state becomes good). Switch to video and audio.

The output unit 7 includes, for example, a display and a speaker, displays the video signal supplied from the decoding unit 6 on the display, and outputs an audio signal to the speaker. The TS analysis unit 5 b is used when performing a channel scan, extracts PSI and SI from the input TS signal, and supplies each information to the control unit 8. Also, the TS analysis unit 5b extracts an identifier (PID: Packet Identifier) of a TS packet including video and audio from the extracted PSI / SI, filters the TS signal by each PID, and performs the video TS packet and audio TS. The packet may be output to a decoding unit or a recording device unit (not shown) and used to view two programs or record a program.
The control unit 8 controls the reception operation of the reception device 1. The operation unit 9 includes a remote controller or a touch panel display, and supplies operation information operated by the user to the control unit 8.

Hereinafter, the reception operation in Embodiment 1 of the present invention will be described with reference to FIG.
FIG. 2 is a flowchart showing the receiving operation of the receiving device 1. This flowchart is started when the user selects a viewing program from the operation unit 9 and the operation information is supplied to the control unit 8.

  First, in step S201, the control unit 8 causes the first reception system 10a and the second reception system 10b to select a physical channel corresponding to a program designated by the user. In step S202, the control unit 8 controls the demodulating unit 4 to perform diversity combining demodulation. The TS signal generated by the diversity combining demodulation is output to the TS analysis unit 5a, and the decoding unit 6 performs decoding processing. Based on the reception quality information at the time of channel selection, video and audio of 12-segment broadcasting or one-segment broadcasting Either video or audio is output to the output unit 7, and a desired program is provided to the user. Through the above processing, the receiving apparatus 1 can view a program using both the first receiving system 10a and the second receiving system 10b.

  Next, the control unit 8 acquires the reception quality information from the demodulation unit 4 in step S203, compares the acquired reception quality information with a predetermined condition in step S204, and if the reception quality information is smaller than the predetermined condition (reception) If the state becomes defective), the process proceeds to step S205. When the reception quality information is larger than the predetermined condition (when the reception state is good), the process returns to step S203, and steps S203 and S204 are repeated. The predetermined condition is, for example, the predetermined condition = 20 dB using the reception CNR for the reception quality information. If the reception CNR is 20 dB or more, the process returns to step S203, and if it is less than 20 dB, the process proceeds to step S205. Note that the numerical values given here are merely examples, and the reception quality information can use BER, PER, or the like instead of the reception CNR.

  Here, step S203 and step S204 can be linked to a switching algorithm from 12-segment broadcasting to one-segment broadcasting performed by the control unit 8 for the decoding unit 6. In this case, the process proceeds from step S204 to step S205 simultaneously with the timing when the decoding unit 6 switches from 12-segment broadcasting to selection of one-segment broadcasting. This eliminates the need for software implementation in step S203 and step S204, thereby reducing the software development load.

  In step S205, a waiting time until the channel scan is started (hereinafter, timer time) is set. The timer time is determined in the scan process in step S211. Therefore, when step S211 has never been performed after the user has selected a viewing program, the timer time is set to a predetermined initial timer value. The initial timer value is “timer time B” described later. The “timer time B” is a relatively short time, and if it can be switched to a channel of a relay station having a good reception state by channel scanning, it is possible to switch from one-segment broadcasting to 12-segment broadcasting program viewing at an early stage.

Next, a timer is started in step S206.
Subsequently, the control unit 8 acquires the reception quality information from the demodulation unit 4 in step S207, and compares the acquired reception quality information with a predetermined condition in step S208. If the reception quality information is larger than the predetermined condition (reception) When the state is recovered), the process returns to step S203, and when the reception quality information is smaller than the predetermined condition (when the reception state remains defective), the process proceeds to step S209. The predetermined condition is, for example, the predetermined condition = 20 dB using the reception CNR for the reception quality information, and when the reception CNR is 20 dB or more for a certain time, the process returns to step S203, and when the reception CNR is less than 20 dB, the process proceeds to step S209. . The numerical value given here is an example, and the reception quality information is not the reception CNR but the BER (the condition for returning to step S203 is, for example, when BER> 2 × 10 ⁻⁴ continues for a certain time) or PER ( As a condition for returning to step S203, for example, a case where PER = 0 continues for a certain period of time can be used. Here, in step S207 and step S208, BER or PER of 12-segment broadcasting is acquired as reception quality information in step S207, and it is determined whether or not 12-segment broadcasting can be received from the acquired information in step S208. If the 12-segment broadcasting can be received, it can be determined that the reception state has been recovered. Alternatively, step S207 and step S208 can be linked to a switching algorithm from one-segment broadcasting to 12-segment broadcasting performed by the control unit 8 for the decoding unit 6. In this case, the process proceeds from step S208 to step S203 simultaneously with the timing when the decoding unit 6 switches from the one-segment broadcasting to the selection of the 12-segment broadcasting.

  In step S209, it is determined whether the timer has reached the timer time set in step S205. If the timer time has not been reached, the process returns to step S207, and steps S207 to S209 are repeated. On the other hand, if the timer time has been reached, since the reception state continues to be poor, it is necessary to perform a channel scan, and thus the process proceeds to step S210.

  In step S210, the control unit 8 controls the demodulation unit 4 to stop diversity combining demodulation, and performs control so that each channel signal supplied from the first reception system 10a and the second reception system 10b is independently demodulated. To do. The TS signal generated by demodulating the channel signal of the first receiving system 10a is output to the TS analyzing unit 5a, and the TS signal generated by demodulating the channel signal of the second receiving system 10b is output to the TS analyzing unit 5b. Thus, the first receiving system 10a can be used as a program viewing system, and the second receiving system 10b can be separated from the program viewing system and used as a receiving system for channel scanning.

  As another method of step S210, the control unit 8 first receives reception quality information (for example, reception CNR of each channel signal) of each channel signal supplied from the demodulation unit 4 from the first reception system 10a and the second reception system 10b. ) To get. Then, the control unit 8 controls the demodulating unit 4 to stop diversity combining demodulation, and performs control so that each channel signal supplied from the first receiving system 10a and the second receiving system 10b is independently demodulated. The TS signal generated by demodulating the channel signal of the reception system having the large reception quality information is sent to the TS analysis unit 5a, and the TS signal generated by demodulating the channel signal of the reception system having the small reception quality information is sent to the TS analysis unit 5b. Is output. As a result, the reception system with the better reception state of the first reception system 10a and the second reception system 10b can be used as the reception system for viewing the program. It is possible to reduce the poor reception state when the number is reduced from two to one.

Subsequently, in step S211, a channel scan for searching for a channel that broadcasts the same content is executed. Details of step S211 will be described later with some examples.
After step S211, the same channel is selected for the program viewing system and the channel scanning system. As for the selected channel, if a channel of a relay station having a better reception state than the viewing channel is found in step S211, a channel of the relay station having a better reception state than the relay channel or the viewing channel is found. If not, it will remain in the current viewing channel. Then, returning to step S202, the control unit 8 causes the demodulating unit 4 to perform diversity combining demodulation, thereby receiving a program using both the first receiving system 10a and the second receiving system 10b. Here, if a channel of a relay station whose reception state is better than the viewing channel is not found in step S211, a state where the reception state is bad (a state where one-segment broadcasting is being watched) continues, step S204. Then, a YES determination is made, and the timer (step S206) until the channel scan is started is immediately started. At that time, the timer time set in step S205 is set to the value determined in the previous step S211.

Next, the scan processing in step S211 will be described with reference to FIGS.
FIG. 3 is a flowchart showing the operation of the scan process. Hereinafter, in step S210, it is assumed that the first reception system 10a is assigned to the program viewing reception system, and the second reception system 10b is assigned to the channel scanning reception system.

  First, in step S301, the control unit 8 causes the second reception system 10b to select the channel of the relay station for the viewing program. The channel of the viewing program relay station is described in the NIT information of the viewing program. The control unit 8 stores all channel information of the relay station in the memory from the NIT information of the viewing program before executing the channel scan.

  Next, in step S302, the control unit 8 acquires reception quality information from the demodulation unit 4, and determines whether or not at least one of 12-segment broadcasting and one-segment broadcasting is in a viewable reception state. If it is determined that the information can be received, the control unit 8 acquires NIT (Network Information Table) information from the TS analysis unit 5b, and the network ID (network_id) included in the NIT information is the network of the viewing program. If it matches the ID, it is determined that this channel is a relay station for the viewing program.

In step S303, it is confirmed whether channel selection has been performed for all channels of the relay station. If there is a channel that has not been selected, the process returns to step S301, and if all channels have been selected, step S303 is performed. The process proceeds to S304.
In step S304, it is confirmed whether or not a receivable relay station channel has been found in step S302. If there is a receivable relay station, a relay station channel having a better reception state than the conventional viewing channel is found. Since it may be found, the process proceeds to step S305. If there is no receivable relay station, the process proceeds to step S307.

In step S305, the channel having the highest reception quality information (that is, the best reception quality) is extracted from the receivable relay station channels found in step S302, and this channel is the same as the channel of the viewing program. Determine whether or not. If it is different from the viewing program, the channel of the relay station having a better reception state than the previous viewing channel has been found, and the process proceeds to step S306. If it is the same as the viewing program, the process proceeds to step S308.
In step S306, the control unit 8 selects the channel of the relay station having the maximum reception quality information for each of the first reception system for program viewing and the second reception system for channel scanning. Subsequently, in step S307, "timer A" set as a timer time for performing the next step S205 is stored in memory, and the scanning process is terminated.

  On the other hand, in step S308, it is confirmed whether or not a receivable relay station channel other than the viewing program channel is found in step S302. If the corresponding channel is found, the reception state of the channel may soon become better than the reception state of the viewing channel so far as it continues to move, so the process proceeds to step S309 and the next step S205 is performed. "Timer B" set as the timer time at the time is stored in memory, and the scanning process is terminated. If no corresponding channel is found, the process advances to step S307 to store “timer A” and the scan process is terminated.

Here, “timer A” and “timer B” will be described.
“Timer B” is shorter than “Timer A”. The condition for setting “timer B” is YES in step S308, that is, as a result of channel scanning, the reception state is poor compared to the channel of the viewing program, but the channel of the receivable relay station is This is the case. In this case, there is a possibility that the reception state of the channel of the viewing program becomes better than the reception state of the channel of the relay station in a short time as the mobile body moves. Therefore, by setting “timer B” to a short time, the frequency of repeating the channel scan can be increased, and when both reception states are reversed, it is possible to quickly switch to the relay station channel.

  Specifically, for example, the following time is set in “timer B”. The maximum time required for the scanning process is approximately 50 seconds if the number of channels of all relay stations to be searched is 50 (the number of all channels of terrestrial digital broadcasting) and the scanning time of one channel is 1 second. In order to increase the frequency of repeating the channel scan, it is desirable that the program viewing using both the first receiving system 10a and the second receiving system 10b is shorter than the time required for the scanning process. What is necessary is just to set the time below second.

On the other hand, if the answer is NO in step S308, that is, if no receivable relay station channel other than the viewing program channel is found, there is no relay station around the mobile unit, so channel scanning is repeated frequently. However, switching of the channel of the relay station does not occur. In step S305, if a relay station channel having a better reception state than the conventional viewing channel is found, a relay station exists in the vicinity of the mobile body, and the good reception state can be continued for a while. The potential is great. Therefore, by setting “timer A” longer than “timer B”, the frequency of repeating the channel scan is reduced, so that the program viewing time using both the first reception system 10a and the second reception system 10b is increased. Thus, it is possible to reduce the occurrence of a situation in which the reception state for program viewing decreases from two to one during channel scanning and the reception state becomes poor.
For example, “timer A” may be set to a time longer than 50 seconds of “timer B” described above in order to prioritize program viewing using the first reception system 10a and the second reception system 10b. Specifically, it is desirable to set a time of about 5 minutes.

  FIG. 4 is a diagram illustrating areas in which broadcast signals transmitted from the first broadcast station and the second broadcast station that is a relay station of the first broadcast station can be received. In FIG. 4, consider the receiving operation of the receiving device 1 when the moving body moves from the first point to the sixth point.

  The first point where the movement starts is a place where both the 12-segment broadcasting and the one-segment broadcasting of the first broadcasting station can be received. The second point is a place where the one-segment broadcasting of the first broadcasting station can be received. The third point is a place where the 1seg broadcasting of the first broadcasting station and the second broadcasting station can be received. The fourth point is a place where the 1seg broadcasting of the second broadcasting station can be received. The fifth point and the sixth point where the movement ends are places where both the 12-segment broadcasting and the one-segment broadcasting of the second broadcasting station can be received. Points a to h on the movement path indicate locations where the channel scan is executed.

  At the first point, the receiving apparatus 1 selects the channel of the first broadcasting station for the first receiving system 10a and the second receiving system 10b, and receives 12-segment broadcasting. When moving to the second point, the receiving device 1 becomes unable to receive 12-segment broadcasting and switches to receiving one-segment broadcasting. Further, the receiving apparatus 1 sets an initial timer value (for example, “timer B”) as a timer time until channel scanning is started. Then, the timer time elapses, and the receiving apparatus 1 executes channel scanning at the point a, while continuing to receive the program at the first receiving system 10a, at the second receiving system 10b. At point a, there is no receivable relay station channel other than the first broadcast station channel, and the receiving apparatus 1 continues to receive the 1seg broadcast of the first broadcast station even after performing the channel scan (in step S308). NO). At this time, “timer A” is set as the timer time until the next channel scan is started. Every time the “timer A” time elapses, a channel scan is performed at points b and c.

  At point c, as a result of the channel scan, it is found that the one-segment broadcasting of the second broadcasting station can be received. However, since the reception state of the first broadcasting station is better, the receiving apparatus 1 is the one-segment broadcasting of the first broadcasting station. Broadcast reception is continued (YES in step S308). At this time, “timer B” shorter than “timer A” is set as the timer time until the next channel scan is started. Every time the “timer B” time elapses, a channel scan is performed at points d, e, and f.

  At the point f, as a result of the channel scan, the receiving state of the second broadcasting station is better than the receiving state of the first broadcasting station, so that the receiving device 1 is connected to the first receiving system 10a and the second receiving system 10b. Is switched to reception of one-segment broadcasting by the second broadcasting station (step S306). At this time, “timer A” is set as the timer time until the next channel scan is started.

  When the time of “timer A” elapses, at channel g, as a result of the channel scan, a channel of a relay station that can be received other than the second broadcast station being viewed is not found. Reception of the one-segment broadcasting is continued (NO in step S308). Further, “timer A” is set as a timer time until the next channel scan is started.

  When the “timer A” time elapses, a channel scan is performed at the point h. However, since the result is the same as that at the point g, the receiving apparatus 1 continues to receive the one-segment broadcasting of the second broadcasting station. When the fifth point is reached, the 12-segment broadcasting of the second broadcasting station can be received, and the receiving apparatus 1 switches to receiving the 12-segment broadcasting (YES in step S208). When the reception state is good (12-segment broadcasting can be received) (NO in step S204), the timer is reset, and the receiving apparatus 1 reaches the sixth point without performing channel scanning.

As described above, the receiving device 1 according to the first embodiment of the present invention can switch the channel to the program in the destination area without interrupting the viewing program.
As a result of the channel scan, if there is no receivable relay station channel other than the viewing program channel, it is assumed that there is no relay station nearby, and the time until the next channel scan starts is increased (“timer A ″), the number of repeated channel scans is reduced. Therefore, both the first receiving system 10a and the second receiving system 10b can be used for viewing the program as much as possible, and the reception condition is poor when the program viewing is continued with only one receiving system during channel scanning. Occurrence can be minimized.

  If there is a relay station channel other than the viewing program channel that can be received as a result of the channel scan, the time until the next channel scan is started is shortened ("timer B"), and the channel scan is repeated. Increase the number of times. Therefore, when the receiving state of the channel of the relay station becomes better than the receiving state of the channel of the viewing program, it is possible to quickly switch to the channel of the relay station.

FIG. 5 is a flowchart showing an operation of scan processing according to the second embodiment of the present invention.
The difference from the scan processing shown in FIG. 3 is that step S501 is added between step S305 and step S306. In FIG. 3, when a channel of the relay station having a better reception state than the channel of the viewing program is found in step S305 as a result of performing the channel scan by the second reception system 10b (reception system for performing channel scan), Switching to this relay station channel was performed. On the other hand, in the second embodiment, step S501 is performed following step S305. In step S305, the control unit 8 acquires, from the demodulation unit 4, the reception quality information of the channel signal of the first reception system (reception system that continues to watch the program during the channel scan) 10a. It is determined whether or not the reception quality information of the channel of the relay station discovered by the two reception systems 10b by the channel scan is a large value, and if it is large, the process proceeds to step S306 and the channel of the relay station is switched.

  The most desirable method is a method of selecting a channel in which the reception state is the best when the program reception by diversity combining demodulation of the first reception system 10a and the second reception system 10b is performed. Such a determination cannot be made because the system is operated independently. However, as shown in the present embodiment, it is determined whether to switch to the relay station in consideration of the reception state of the first reception system 10a, so that a more appropriate channel can be used for program viewing compared to the first embodiment. You can choose.

FIG. 6 is a flowchart showing the operation of the scanning process according to the third embodiment of the present invention.
The difference from the scan processing shown in FIG. 5 is that, when NO is determined in step S501, step S601 for setting “timer C” as a timer time when performing next step S205 is added. Here, “timer C” is a time when “timer C” <“timer B” <“timer A”.

  As described above, the channel scan is performed, and the second reception system 10b (the reception system that performs the channel scan) finds the channel of the relay station that has a better reception state than the channel of the viewing program, but the first reception system 10a ( In a situation where the reception status is poor for a viewing program of a receiving system that continues to watch the program during channel scanning, if the surrounding reception status changes due to the movement of the mobile object, it takes a short time. There is a possibility that the reception status should be switched to the relay station. Accordingly, by setting the time until the next channel scan is started to be shorter than “timer B”, switching to the relay station can be performed at a more appropriate timing.

FIG. 7 is a flowchart showing an operation of scan processing according to the fourth embodiment of the present invention.
The difference from the scan processing shown in FIG. 3 is that step S701 is added between step S308 and step S309.

  As a result of the channel scanning performed by the second receiving system 10b (the receiving system that performs channel scanning), the receiving state of the channel of the viewing program is the best, but the relay station that can receive other than the channel of the viewing program in step S308 If no channel is found, step S701 is performed. In step S701, the control unit 8 receives the reception quality information of the channel of the viewing program and the channel of the relay station that can be received other than the channel of the viewing program (if there are a plurality of corresponding channels, the control station 8 that has the best reception state). Channel) reception quality information is compared, and if the difference value is within the predetermined range, the process proceeds to step S309, where "timer B" is set. If it is outside the predetermined range, the process proceeds to step S307, where "timer A" is set.

Thereby, the channel of the relay station that can be received by the channel scan is found, but when the reception state is lower than the predetermined range as compared with the channel of the viewing program, it is not a short-time “timer B” but a long time. “Timer A” is set.
As described above, the frequency of performing the channel scan can be increased only when moving to a place where the channel switching to the relay station is likely to occur due to the channel scan, and the number of times of performing the channel scan can be reduced.

FIG. 8 is a block diagram illustrating a configuration of the receiving device 1 according to the fifth embodiment of the present invention.
The difference from the configuration of the receiving device 1 shown in FIG. 1 is that the speed information acquisition unit 11 is added. The speed information acquisition unit 11 acquires the movement speed of the moving body on which the receiving device 1 is mounted from a device such as a car navigation (not shown), and supplies the acquired movement speed information to the control unit 8.
Hereinafter, the operation of the scan processing in the fifth embodiment will be described with reference to FIG.

FIG. 9 is a flowchart showing an operation of scan processing according to the fifth embodiment of the present invention.
The difference from the scan processing shown in FIG. 3 is that step S307 in FIG. 3 is changed to steps S901 and S902, and step S309 in FIG. 3 is changed to steps S901 and S903.

In step S <b> 901, the control unit 8 acquires the speed information of the moving body from the speed information acquisition unit 11 and stores it. In step S902, the control unit 8 sets (timer 1) as a timer time for performing the next step S205.
Timer time = α / (moving speed) (Equation 1)
Here, α is a coefficient for setting so that the channel scan is executed when the moving body moves a predetermined distance. For example, when control is performed so that channel scanning is performed every time the moving body moves 10 km, assuming that α = 10 km and the moving speed of the moving body is 40 km / h, timer time = (10 km) / (40 km /H)=0.25h=15 minutes is set.

In step S903, the control unit 8 sets (timer 2) as a timer time for performing the next step S205.
Timer time = β / (moving speed) (Equation 2)
Here, β is a coefficient for setting so that the channel scan is executed when the moving body moves a predetermined distance, similarly to α in step S902. However, if β <α, the channel scan is worse than the channel reception status of the viewing program, but if a receivable relay station channel is found, the channel scan is performed even if the moving distance of the moving object is short To be.

  When the predetermined timer times “timer A”, “timer B”, and “timer C” are used as in the first to fourth embodiments of the present invention, the channel is set every predetermined time even if the moving body does not move. Repeated scanning. On the other hand, in this embodiment, since the timer time is set using the moving speed of the moving body, a channel scan can be performed when the moving body moves a predetermined distance. Therefore, since channel scanning is performed in a situation where the radio wave environment around the mobile object has changed reliably, there is an effect that channel scanning can be executed at a more appropriate timing.

In the embodiment of the present invention described above, the receiving device 1 has been described with respect to the configuration having the two receiving systems of the first receiving system 10a and the second receiving system 10b. However, the receiving apparatus 1 is configured by three or more receiving systems. Is also possible. For example, in the case of four reception systems, the same channel is normally selected for the four reception systems, and each channel signal is supplied to the demodulation unit 4. The demodulator 4 performs diversity combining demodulation using the four channel signals, and outputs the generated TS signal to the TS analyzer 5a, so that the four reception systems can be used for program viewing. When performing channel scanning, any two receiving systems may be assigned to channel scanning receiving systems, and the remaining two receiving systems may be assigned to view programs. As described above, the configuration including four reception systems can realize more stable program reception and improve the scanning performance of the channel scan as compared with the configuration including two reception systems. it can.
Thus, the embodiment described so far is merely an example and does not limit the present invention. While different embodiments can be considered based on the spirit of the present invention, all fall within the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Reception apparatus, 2a, 2b ... Antenna part, 3a, 3b ... Channel selection part, 4 ... Demodulation part, 5a, 5b ... TS analysis part, 6 ... Decoding part, 7 ... Output part, 8 ... Control part, 9 ... Operation , 10a... First reception system, 10b... Second reception system, 11.

Claims (9)

A receiving device for receiving a broadcast signal,
A plurality of receiving systems for receiving a broadcast signal and selecting a predetermined channel;
A control unit for controlling the reception operation of the plurality of reception systems,
When the reception state of the broadcast radio wave is good, the control unit performs the program reception process by selecting and combining the same channel with the plurality of reception systems,
When the reception state of the broadcast radio wave becomes poor and a predetermined time has elapsed, the control unit divides the plurality of reception systems for program reception and channel scanning, and the reception system for program reception continues program reception, The channel scan receiving system performs a channel scan process for searching for a channel that broadcasts the same content as the viewing program,
In the channel scan process, the control unit determines that the predetermined time is the first time when a channel that broadcasts the same content in addition to the viewing program cannot be found.
In addition, when the channel scanning process finds a channel that broadcasts the same content in addition to the viewing program, although the reception quality is inferior to that of the viewing program, the predetermined time is shorter than the first time. A receiving apparatus that controls to set the second time. A receiving device for receiving a broadcast signal,
A plurality of receiving systems for receiving a broadcast signal and selecting a predetermined channel;
A control unit for controlling reception operations of the plurality of reception systems;
A speed information acquisition unit that acquires a moving speed at which the receiving device moves;
When the reception state of the broadcast radio wave is good, the control unit performs program reception processing by selecting and synthesizing the same channel for the plurality of reception systems,
When the reception state of the broadcast radio wave becomes poor and a predetermined time has elapsed, the control unit divides the plurality of reception systems for program reception and channel scanning, and the reception system for program reception continues program reception, The channel scan receiving system performs a channel scan process for searching for a channel that broadcasts the same content as the viewing program,
In the channel scanning process, when the channel that broadcasts the same content in addition to the viewing program cannot be found, the control unit sets the predetermined time as the first time (= first moving distance / moving speed),
In addition, when the channel scanning process finds a channel that broadcasts the same content in addition to the viewing program, although the reception quality is inferior to the viewing program, the control unit sets the predetermined time to the second time (= second time). The moving distance / the moving speed, the first moving distance> the second moving distance). The receiving apparatus according to claim 1 or 2,
When the reception state of the broadcast radio wave is poor,
The program content of the channels received by the plurality of receiving systems is a point in time when the program is switched from a weak-layer transmission program having a relatively weak resistance to errors occurring during transmission to a relatively strong strong-layer program. A receiving device. The receiving apparatus according to claim 1 or 2,
When dividing the plurality of reception systems into program reception and channel scanning, a reception system having a good broadcast radio wave reception state is used for program reception, and the remaining reception system is used for channel scanning. . A receiving method for receiving a broadcast signal,
A plurality of receiving steps for receiving a broadcast signal and selecting a predetermined channel;
A control step for controlling a reception operation of the plurality of reception steps,
The control step includes
If the reception state of the broadcast radio wave is good, the plurality of reception steps select and synthesize the same channel to perform program reception processing,
When the reception state of the broadcast radio wave becomes poor and a predetermined time elapses, the plurality of reception steps are divided into program reception and channel scan, and the program reception reception step continues program reception, and the channel scan The receiving step performs a channel scan process to search for a channel that broadcasts the same content as the program being viewed,
The predetermined time,
If the channel scanning process cannot find a channel that broadcasts the same content in addition to the viewing program, at the first time,
If the channel scanning process finds a channel that broadcasts the same content in addition to the viewing program although the reception quality is inferior to that of the viewing program, control is performed to set the second time shorter than the first time. A receiving method characterized by the above. A receiving method for a receiving apparatus for receiving a broadcast signal,
A plurality of receiving steps for receiving a broadcast signal and selecting a predetermined channel;
A control step for controlling a reception operation of the plurality of reception steps;
A speed information obtaining step for obtaining a moving speed at which the receiving device moves,
The control step includes
If the reception state of the broadcast radio wave is good, the plurality of reception steps select and synthesize the same channel to perform program reception processing,
When the reception state of the broadcast radio wave becomes poor and a predetermined time elapses, the plurality of reception steps are divided into program reception and channel scan, and the program reception reception step continues program reception, and the channel scan The receiving step performs a channel scan process to search for a channel that broadcasts the same content as the program being viewed,
The predetermined time,
If a channel that broadcasts the same content in addition to the viewing program cannot be found in the channel scan process, at the first time (= first moving distance / moving speed),
In the channel scanning process, if a channel that broadcasts the same content can be found in addition to the viewing program, although the reception quality is inferior to that of the viewing program, the second time (= second moving distance / moving speed, first The receiving method is characterized in that control is performed such that the moving distance> the second moving distance). The receiving method according to claim 5 or 6,
When the reception state of the broadcast radio wave becomes poor,
The program content of the channel received by the plurality of receiving steps is a point in time when the program is switched from a weak layer transmission program having a relatively weak resistance to errors occurring during transmission to a relatively strong strong layer program. A characteristic reception method. A receiving method for receiving a broadcast signal,
A reception quality determination step for determining whether or not the reception quality of the viewing program to be received and viewed is within a predetermined range;
A timer step that starts counting time when the reception quality determination step determines that the reception quality is poorer than a predetermined range;
If the reception quality determined in the reception quality determination step does not recover within a predetermined range before the time counted in the timer step reaches a predetermined time, a channel that broadcasts the same content as the viewing program is searched. A channel scanning step to
The predetermined time is
In the channel scanning step, if a channel that broadcasts the same content in addition to the viewing program cannot be found, the first time,
In the channel scanning step, the reception quality is inferior to that of the viewing program, but if a channel that broadcasts the same content can be found in addition to the viewing program, the channel is set to a second time shorter than the first time. A receiving method characterized by the above. A receiving method for a receiving apparatus for receiving a broadcast signal,
A reception quality determination step for determining whether or not the reception quality of the viewing program to be received and viewed is within a predetermined range;
A timer step that starts counting time when the reception quality determination step determines that the reception quality is poorer than a predetermined range;
If the reception quality determined in the reception quality determination step does not recover within a predetermined range before the time counted in the timer step reaches a predetermined time, a channel that broadcasts the same content as the viewing program is searched. A channel scan step to
A speed information acquisition step of acquiring a moving speed at which the receiving device moves;
The predetermined time is
In the channel scanning step, if a channel that broadcasts the same content in addition to the viewing program cannot be found, at a first time (= first moving distance / moving speed),
When the channel scanning step finds a channel that broadcasts the same content in addition to the viewing program, although the reception quality is inferior to that of the viewing program, the second time (= second travel distance / movement speed, 1 moving distance> second moving distance).

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