JP6061340B2 - Broadcast receiver - Google Patents

Description

  The present invention relates to a broadcast receiving apparatus capable of receiving digital audio broadcast and analog audio broadcast, and in particular, switching between digital audio broadcast and analog audio broadcast according to the reception state during reception of a program being simulcast. It is related with the broadcast receiver to perform.

  Conventionally, so-called simulcast, in which the same program is broadcast simultaneously in digital audio broadcasting and analog audio broadcasting, has been performed. For example, in Europe, simulcast is performed by digital audio broadcasting called Digital Audio Broadcasting (hereinafter referred to as DAB) and analog audio broadcasting called FM or Radio Data System (hereinafter referred to as RDS).

  A broadcast receiver that receives such an audio broadcast automatically selects a digital audio broadcast program preferentially within a digital audio broadcast service area when receiving a broadcast of a program being simulcast. Also, depending on the reception status, such as automatically switching to receive analog audio broadcast programs when moving out of the service area of digital audio broadcasts due to movement in automobiles, etc. Switching is performed.

  As a conventional broadcast receiver, a broadcast receiver described in Patent Document 1 below is known.

  As shown in FIG. 5, a broadcast receiver 900 described in Patent Document 1 includes a first receiving unit 901, a second receiving unit 902, an output unit 903, a switching unit 904, a delay unit 905, Time difference detection means 906.

  The first receiving unit 901 receives the first broadcast signal. The second receiving means 902 receives a second broadcast signal having the same content as the first broadcast signal. The output unit 903 outputs the reception signal of the first reception unit 901 or the reception signal of the second reception unit 902. The switching unit 904 changes the reception signal output from the output unit 903 from the reception signal of the first reception unit 901 to the reception signal of the second reception unit 902 or from the reception signal of the second reception unit 902. 1 is switched to the reception signal of the reception means 901. The delay means 905 determines the time difference between the reception signal of the first reception means 901 or the reception signal of the second reception means 902 and the reception signal of the first reception means 901 and the reception signal of the second reception means 902. Delay by the delay time and set the time difference to zero. The time difference detection unit 906 detects a time difference between the reception signal of the first reception unit 901 and the reception signal of the second reception unit 902.

  The switching unit 904 receives the signal when the time difference between the reception signal of the first reception unit 901 and the reception signal of the second reception unit 902 detected by the time difference detection unit 906 is zero by the delay unit 905. Perform signal switching.

  A technique for detecting a time difference (delay time) is disclosed in which a time difference (delay time) is detected by correlating a received digital broadcast with another broadcast having the same content at a certain time. Yes.

JP-A-11-55135

  However, in the above-described prior art broadcast receiver, the sound quality obtained is different between the digital audio broadcast reception signal and the analog audio broadcast reception signal. This may occur and the switching timing may be shifted. Further, in order to reduce the timing shift due to an error, it is conceivable to increase the number of comparisons. However, there is a problem that the processing time may increase due to an increase in the calculation amount.

  The present invention solves the above-described problems, and by changing the accuracy of analysis according to the type of program, it is possible to minimize the time required for analysis within a range where accuracy is not degraded. The purpose is to provide a machine.

In order to solve this problem, a broadcast receiver according to the present invention includes a first receiving circuit that receives a digital audio broadcasting program, a second receiving circuit that receives an analog audio broadcasting program, and the second receiving circuit. A control unit that performs channel selection control so that a program received by the receiving circuit is the same as a program received by the first receiving circuit, a first audio signal output by the first receiving circuit, Switching means for outputting one or both of the second audio signals output from the second receiving circuit, and the time between the first audio signal and the second audio signal; The time difference analyzing means for analyzing the deviation, the time difference control means for delaying the second audio signal based on the time difference detected by the time difference analyzing means, and the type of program received by the first receiving circuit are acquired. Program content acquisition means, During differential analyzing means is capable of operating time difference analysis by changing the analysis precision, the control unit, in accordance with the program content that the program content acquisition unit has acquired, the time difference analysis means performs a correlation analysis The time difference analysis is performed by changing the number of times to change the analysis accuracy.

  According to this, by changing the accuracy of the time difference analysis according to the type of program, it is possible to provide a broadcast receiver that can keep the time required for the analysis to a minimum within a range that does not reduce the accuracy. .

In the broadcast receiver according to the present invention, the control unit includes a memory, the digital audio broadcast is Digital Audio Broadcasting (DAB), and the program content acquisition means is a Program included in the digital audio broadcast. The number of times of performing the correlation analysis is set by checking Type (PTy) and comparing the Int Code included in the information of the PTy with a database stored in the memory in advance .

  According to this, by examining Program Type (hereinafter referred to as PTy) included in a DAB broadcast signal, the type of program can be easily and accurately examined.

  According to the present invention, it is possible to provide a broadcast receiver capable of minimizing the time required for analysis within a range where accuracy is not reduced by changing the accuracy of analysis according to the type of program. .

It is a block diagram which shows the structure of the broadcast receiver which concerns on embodiment of this invention. It is a figure explaining the data content of the broadcast signal of a DAB system. It is a figure which shows the example of the data table which shows the relationship between PTy and the precision of analysis. It is a flowchart explaining operation | movement of the broadcast receiver which concerns on this embodiment. It is a block diagram which shows the structure of the broadcast receiver of a prior art.

[First Embodiment]
The broadcast receiver 100 in the first embodiment will be described below.

  First, the configuration of the broadcast receiver 100 in the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of the broadcast receiver 100.

  As shown in FIG. 1, the broadcast receiver 100 includes a first receiving circuit 1, a second receiving circuit 2, a control unit 3, a switching unit 4, a time difference analysis unit 5, and a time difference control unit 6. , And a program content acquisition means 7.

  The first receiving circuit 1 includes a first channel selection unit 1 a and a decoding unit 1 b and is connected to the control unit 3. The output of the first channel selection unit 1 a is connected to the decoding unit 1 b and the program content acquisition unit 7, and the output of the decoding unit 1 b is connected to the switching unit 4 and the time difference analysis unit 5. The first channel selection unit 1 a selects and receives a DAB digital audio broadcast program under the control of the control unit 3. The decoding unit 1b converts the received signal into a first audio signal that is a digital signal, and outputs the first audio signal to the switching unit 4 as an output signal. Further, the first receiving circuit 1 outputs a signal indicating the reception state, such as an RSSI (Received Signal Strength Indication) signal indicating the electric field strength of the received signal or a BER (Bit Error Rate) to the control unit 3.

  The second receiving circuit 2 includes a second channel selection unit 2 a and a conversion unit 2 b and is connected to the control unit 3. The output of the conversion unit 2 b is connected to the time difference analysis means 5 and the time difference control means 6. The second channel selection unit 2 a selects and receives an analog audio broadcast program under the control of the control unit 3. The converter 2b converts the signal received by the channel selection into a second audio signal that is a digital signal, and outputs it to the time difference control means 6 as an output signal. In addition, the second receiving circuit 2 outputs a signal indicating the reception state, such as an RSSI signal indicating the electric field strength of the received signal, to the control unit 3.

  The time difference control means 6 is constituted by a storage circuit called a memory, and is connected to the second receiving circuit 2, the switching means 4, and the control unit 3. The time difference control means 6 sequentially takes in the second audio signal supplied from the second receiving circuit 2 under the control of the control unit 3. Further, under the control of the control unit 3, the captured second audio signal is sequentially output to the switching means 4 in the same order as the captured second audio signal. The time from when the time difference control means 6 takes in the second audio signal until it starts to output is the delay time for delaying the second audio signal.

  The switching unit 4 is connected to the output of the decoding unit 1 b of the first receiving circuit 1, the time difference control unit 6, and the control unit 3. The switching unit 4 is a first audio signal output from the decoding unit 1 b of the first receiving circuit 1 and an output signal from the second receiving circuit 2 that has passed through the time difference control unit 6 under the control of the control unit 3. The audio signal is switched to one of the two audio signals and output. In the middle of the switching, both audio signals can be mixed and output.

  The time difference analyzing means 5 is connected to the output of the decoding unit 1b of the first receiving circuit 1 and the output of the converting unit 2b of the second receiving circuit 2. The time difference analysis means 5 is configured to be able to analyze the time difference by changing the analysis accuracy under the control of the control unit 3. The time difference analyzing means 5 is controlled by the control unit 3 so that the first audio signal output from the decoding unit 1b of the first receiving circuit 1 and the second audio signal that is an output signal from the second receiving circuit 2 are used. From the correlation, the time lag between the first audio signal and the second audio signal is analyzed. Further, the time difference analysis means 5 outputs the analysis result to the control unit 3.

  The program content acquisition means 7 is connected to the first channel selection unit 1 a and the control unit 3 of the first reception circuit 1. The program content acquisition means 7 acquires the information of the Pty that is included in the output signal of the digital audio broadcasting and includes the type of program received by the first channel selection unit 1a and that indicates the program content. Accordingly, the PTy information indicating the acquired program content is output to the control unit 3.

  The control unit 3 is connected to the first receiving circuit 1, the second receiving circuit 2, the switching unit 4, the time difference analyzing unit 5, the time difference controlling unit 6, and the program content acquiring unit 7. The control unit 3 controls the channel selection so that the first reception circuit 1 receives a digital audio broadcast program, and the RSSI signal indicating the reception state from the first reception circuit 1 or a signal such as BER. To get. Further, the second receiving circuit 2 is selected and controlled so as to receive an analog audio broadcast program that is the same as the program received by the first receiving circuit 1, and the second receiving circuit 2. A signal such as an RSSI signal indicating the reception state is acquired from the above.

  The control unit 3 controls the program content acquisition unit 7, acquires the information about the Pty indicating the program content acquired by the program content acquisition unit 7, examines the acquired Pty information, and analyzes the time difference according to the result of the examination. The accuracy of the time difference analysis operation performed by the means 5 is determined. Further, the time difference analyzing means 5 is controlled based on the determined accuracy of the time difference analyzing operation to analyze the time lag, and the analysis result is acquired from the time difference analyzing means 5.

  Based on the time difference detected by the time difference analysis means 5, the control unit 3 controls the delay time given to the second audio signal by the time difference control means 6 to be the same as the time difference detected by the time difference analysis means 5.

  As described above, the control unit 3 controls the first reception circuit 1, the second reception circuit 2, the switching unit 4, the time difference analysis unit 5, the time difference control unit 6, and the program content acquisition unit 7. Further, the control unit 3 is provided with a timer function and a memory (not shown), manages the control interval by the timer function, the value of the acquired signal such as RSSI signal and BER, Pty information indicating the program content, time difference Information on the result of analysis can be stored or calculated.

  Next, a DAB broadcast signal will be described with reference to FIG. FIG. 2 is a diagram for explaining the data content of a DAB broadcast signal, and FIG. 2 (a) is a diagram showing a data frame structure. FIG. 2B is an explanatory diagram of PTY information FIG 0/17 (Type 0 field for extension 17) included in a high-speed information channel (Fast Information Channel: hereinafter referred to as FIC). FIG. 2C illustrates the Int code included in the PTY information.

  As shown in FIG. 2 (a), a DAB broadcast signal is composed of a synchronization channel (Sync. Channel: labeled SYNC in FIG. 2 (a)), FIC, and MSC (Main Service Channel). Has been sent in.

  The FIC includes information indicating in which area of the MSC the data of the selected service is located, and information such as time, date information, service content and title. As shown in FIG. 2B, the PTy information FIG0 / 17 included in the FIC includes information such as SId, S / D flag, Rfa, Rfu, and Int Code.

  Although the detailed description of each piece of information is omitted, for example, SId is a service identifier that identifies a service, and Int Code is a program type code by an international code.

  Specifically, as shown in FIG. 2C, the Int Code is individually assigned a program type for 5-bit information. Therefore, by acquiring this Int Code, the contents of the program can be known. Can do.

  Next, the operation of the broadcast receiver 100 of this embodiment will be described with reference to FIGS. FIG. 3 is a diagram showing an example of a data table showing the relationship between PTY and the accuracy of analysis, and the description will be made assuming that this data table is stored in advance in a memory included in the control unit 3 of the broadcast receiver 100. FIG. 4 is a flowchart for explaining the operation of the broadcast receiver 100 of the present embodiment, and shows a processing procedure executed by the control unit 3 of the broadcast receiver 100. The processing procedure shown in the flowchart of FIG. 4 is executed when the broadcast receiver 100 is turned on, or when a broadcast is selected according to a user operation or a change in reception status.

  In step S1 of the flowchart shown in FIG. 4, the control unit 3 controls the first channel selection unit 1a of the first reception circuit 1 to select and receive a DAB digital audio broadcast program.

  Next, in step S2, the control unit 3 controls the second channel selection unit 2a of the second reception circuit 2 to select and receive an analog audio broadcast program. In this case, the control unit 3 controls the program content acquisition means 7, and from the FI (frequency information) included in the FIC of the DAB digital audio broadcast received by the first receiving circuit 1, the frequency of the FM broadcast of the same content Information can be obtained and this FM broadcast can be received.

  In step S3, the control unit 3 controls the program content acquisition unit 7 to acquire the information on the PTY contained in the FIC of the DAB digital audio broadcast received by the first receiving circuit 1 (see FIG. 2B). The process proceeds to step S4.

  In step S4, the control unit 3 collates the Int Code included in the Pty information acquired in step S3 with a database (see FIG. 3) stored in advance. As a result of checking, if it is determined that Type “A”, the process proceeds to Step S5. If it is determined that Type “B”, the process proceeds to Step S6. If it is determined that Type “C”, the process proceeds to Step S7. Transition.

  In step S5, since it is determined that the type “A” (Fast mode) is determined in step S4, the control unit 3 sets the value of the number of times NA the time difference analysis means 5 performs the correlation analysis to “5”, and proceeds to step S8. To do.

  In step S6, since it is determined that the type is “B” (Medium mode) in step S4, the control unit 3 sets the value of the number NA that the time difference analysis means 5 performs the correlation analysis to “10”, and proceeds to step S8 To do.

  In step S7, since it is determined in step S4 that Type “C” (Static mode), the control unit 3 sets the value of the number of times NA the time difference analysis means 5 performs the correlation analysis to “15”, and proceeds to step S8. To do.

  In step S8, the control unit 3 outputs the value NA of the number of times of performing the correlation analysis set in any of step S5, step S6, or step S7 to the time difference analysis means 5, and proceeds to step S9.

  The time difference analysis means 5 performs the time difference analysis by changing the number of times of correlation analysis according to the value of the number NA of correlation analysis set by the control unit 3. For this reason, the smaller the value NA of correlation analysis, the shorter the time required for analysis and the lower the analysis accuracy. The larger the value NA, the longer the time required for analysis and the higher the analysis accuracy.

  In step S9, the control unit 3 waits for the time difference analysis means 5 to complete the analysis of the time difference and proceeds to step S10.

  In step S10, the control unit 3 acquires the analysis result from the time difference analysis means 5, and stores the analysis result of the time difference acquired in step S10 in the memory included in the control unit 3 in step S11.

  In step S12, the control unit 3 controls the time difference control means 6 based on the analysis result of the time difference acquired in step S10, and proceeds to step S13.

  In step S <b> 13, the control unit 3 outputs to the switching unit 4 the first audio signal output from the decoding unit 1 b of the first receiving circuit 1 and the output signal from the second receiving circuit 2 that has passed through the time difference control unit 6. The second audio signal is switched to one of the second audio signals and output, and the process ends. At this time, control is performed so as to select an output signal that is determined to obtain a better reception state from the RSSI signal output from the first receiving circuit 1, the RSSI signal output from the second receiving circuit 2, or the like. can do.

  Hereinafter, the effect by having set it as this embodiment is demonstrated.

  In the broadcast receiver 100 of the present embodiment, the first receiving circuit 1, the second receiving circuit 2, the control unit 3, the switching unit 4, the time difference analysis unit 5, the time difference control unit 6, and the program content Acquisition means 7. The time difference analysis means 5 can perform the time difference analysis operation by changing the analysis accuracy, and the control unit 3 changes the analysis accuracy of the time difference analysis means 5 according to the program content acquired by the program content acquisition means 7. Then, it was configured to analyze the time difference.

  Therefore, by changing the accuracy of the time difference analysis according to the type of program, it is possible to provide a broadcast receiver that can keep the time required for the analysis to a minimum within a range that does not reduce the accuracy.

  In the broadcast receiver 100 of the present embodiment, the digital audio broadcast received by the first receiving circuit 1 is DAB, and the program content acquisition unit 7 acquires and checks the Pty included in the digital audio broadcast. Configured.

  For this reason, the kind of program can be investigated easily and accurately.

  As described above, the broadcast receiver 100 according to the embodiment of the present invention has been specifically described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Is possible. For example, the present invention can be modified as follows, and these embodiments also belong to the technical scope of the present invention.

  (1) In the present embodiment, the Int Code included in the Pty information is examined, and an example in which the accuracy of the time difference analysis is changed based on the result is described. However, the time difference analysis is performed using other information. It is also possible to carry out the modification by changing the accuracy.

( 2 ) In the present embodiment, the data used in the control unit 3 has been described with specific numerical values. However, the data may be appropriately changed according to the assumed usage state, and may be a fixed value. The numerical values exemplified in (1) may be changed so as to be corrected in accordance with changes in the operating environment or the like.

DESCRIPTION OF SYMBOLS 1 1st receiving circuit 1a 1st channel selection part 1b Decoding part 2 2nd receiving circuit 2a 2nd channel selection part 2b Conversion part 3 Control part 4 Switching means 5 Time difference analysis means 6 Time difference control means 7 Program content acquisition means 100 Broadcast reception Machine

Claims (2)

A first receiving circuit for receiving a digital audio broadcast program;
A second receiving circuit for receiving an analog audio broadcast program;
A control unit that controls channel selection so that the program received by the second receiving circuit is the same as the program received by the first receiving circuit;
Switching means for outputting one of the first audio signal output from the first receiving circuit and the second audio signal output from the second receiving circuit, or a mixture of both;
A time difference analysis means for analyzing a time lag between the first audio signal and the second audio signal;
Time difference control means for delaying the second audio signal according to the time difference detected by the time difference analysis means;
Program content acquisition means for acquiring the type of program received by the first receiving circuit,
The time difference analysis means is capable of performing a time difference analysis operation by changing the analysis accuracy.
The control unit performs time difference analysis by changing the analysis accuracy by changing the number of times the time difference analysis unit performs correlation analysis according to the program content acquired by the program content acquisition unit. Broadcast receiver. The control unit has a memory,
The digital audio broadcasting is digital audio broadcasting (
DAB)
The program content acquisition means is a Program Type included in the digital audio broadcast.
pe (PTy) is checked , and the number of times of performing the correlation analysis is set by comparing Int Code included in the information of the Pty with a database stored in the memory in advance. The broadcast receiver according to claim 1.