EP3001587A1

EP3001587A1 - Radio broadcasting reception device and method for switching reception broadcasting services

Info

Publication number: EP3001587A1
Application number: EP15185055.9A
Authority: EP
Inventors: Yoshihisa Iwamoto
Original assignee: Alpine Electronics Inc
Current assignee: Alpine Electronics Inc
Priority date: 2014-09-26
Filing date: 2015-09-14
Publication date: 2016-03-30
Anticipated expiration: 2035-09-14
Also published as: JP6288776B2; JP2016072642A; EP3001587B1

Abstract

When the reception quality of a currently received broadcasting service deteriorates, a sound is output by cross-fading a sound signal of the currently received broadcasting service with a sound signal of another broadcasting service of which the program content is the same as that of the currently received broadcasting service in such a manner that the switching is performed gradually. The duration of cross-fading the sounds from the start to the end of the switching is set to a short duration (Fig. 4A) if the broadcasting standard, such as DAB, DAB+ or FM broadcast, of the broadcasting service before switching and that of after switching are the same, and the duration is set to a longer duration (Fig. 4B) if the broadcasting standards are different.

Description

The present invention relates to a feature for switching a reception broadcasting service from a broadcasting service being currently received to another broadcasting service, the content of which is the same as that of the broadcasting service being currently received by a radio broadcasting reception device for receiving a plurality of radio broadcasts adhering to different broadcasting standards.
There is well known a feature for switching a reception broadcasting service from a broadcasting service being currently received to another broadcasting service (a simultaneous broadcast of the broadcasting service being currently received), the content of which is the same as that of the broadcasting service being currently received in a radio broadcasting reception device for receiving a plurality of radio broadcasts adhering to different broadcasting standards, a radio broadcasting reception device for receiving Digital Audio Broadcasting (DAB) services and FM broadcasts, in which, when a broadcasting service being currently received is a DAB service and the reception quality while receiving the current broadcasting service deteriorates, the broadcasting service to be received is switched to another DAB service or an FM broadcast, the content of which is the same as that of the DAB service being currently received (see for example, JP 2013-120967 A and JP 2012-249277A ).
In the radio broadcasting reception device for receiving a plurality of radio broadcasts adhering to different broadcasting standards, when a reception broadcasting service is switched from a broadcasting service being currently received to another broadcasting service, the content of which is the same as that of the currently received broadcasting service, instantaneous switching may result in rapid changes in the volume and the quality of output sound, thereby annoying the user.
Meanwhile, when switching a reception target broadcasting service to another service, if the switching of the sound signal is carried out so as to gradually cross-fade from the sound signal of the broadcasting service before switching to the sound signal of the broadcasting service after switching, rapid changes in the volume and the quality of the output sound can be suppressed from occurring.
In such a case, however, a period for the output of the sound of the broadcasting service before switching, the reception quality of which deteriorates, becomes longer compared with a case where the broadcasting service is switched instantaneously, and noise is output due to defective reception during switching, which could further annoy the user.
Accordingly, it is an object of the present invention to provide a radio broadcasting reception device for receiving a plurality of radio broadcasts adhering to different broadcasting standards, the radio broadcasting reception device being capable of switching a broadcast service to be received as quickly as possible in such a manner as to minimize annoyance.
The invention relates to a radio broadcasting reception device and a method according to the independent claims.
According to an aspect of the present invention, a radio broadcasting reception device capable of receiving a plurality of radio broadcasts adhering to different broadcasting standards includes a reception state detection section for detecting a reception quality of a currently received broadcasting service which is a broadcasting service being received and the sound of which is being output, and a broadcasting service switching section for switching from a switching source broadcasting service, which is the currently received broadcasting service, to a switching destination broadcasting service, which is a broadcasting service of which the content is the same as that of the currently received broadcasting service and the reception quality of which is good, when the reception quality of the currently received broadcasting service deteriorates. In this case, the broadcasting service switching section includes a cross-fade time setting section that sets a cross-fade time to a first time period when the switching source broadcasting service and the switching destination broadcasting service are of a same broadcasting standard, and sets a cross-fade time to a second time period, which is longer than the first time period, when the switching source broadcasting service and the switching destination broadcasting service are of different broadcasting standards, and a mix section that performs switching from the switching source broadcasting service to the switching destination broadcasting service in such a manner that the mix section starts to receive the switching destination broadcasting service while still receiving the switching source broadcasting service, and outputs a sound to be output by cross-fading a sound signal of the switching source broadcasting service with a sound signal of the switching destination broadcasting service in such a manner that the switching is performed gradually over the time period set as the cross-fade time.
In the radio broadcasting reception device of this aspect, the plurality of different broadcasting standards may include DAB and FM broadcasts, DAB+ and FM broadcasts, DAB and DAB+ broadcasts or DAB, DAB+ and FM broadcasts.
According to another aspect of the present invention, a radio broadcasting reception device capable of receiving digital radio broadcasts and analog radio broadcasts includes a reception state detection section for detecting a reception quality of a currently received broadcasting service which is a broadcasting service being received and the sound of which is being output, and a broadcasting service switching section for, if the currently received broadcasting service is a broadcasting service of a digital radio broadcast, switching from a switching source broadcasting service, which is the currently received broadcasting service, to a switching destination broadcasting service, which is a broadcasting service of which the content is the same as that of the currently received broadcasting service and the reception quality of which is good, when the reception quality of the currently received broadcasting service deteriorates. In this case, the broadcasting service switching section includes a cross-fade time setting section that sets a cross-fade time to a first time period when the switching destination broadcasting service is a broadcasting service of digital radio broadcasting, and sets a cross-fade time to a second time period, which is longer than the first time period, when the switching destination broadcasting service is a broadcasting service of analog radio broadcasting, and a mix section that performs switching from the switching source broadcasting service to the switching destination broadcasting service in such a manner that the mix section starts to receive the switching destination broadcasting service while still receiving the switching source broadcasting service, and outputs a sound to be output by cross-fading the sound of the switching source broadcasting service with the sound of the switching destination broadcasting service in such a manner that the switching is performed gradually over the time period set as the cross-fade time.
In the radio broadcasting reception device of this aspect, the digital radio broadcast may be a DAB broadcast and the analog radio broadcast may be an FM broadcast. In addition, the digital radio broadcasting may be a DAB+ broadcast and the analog radio broadcasting may be an FM broadcast.
Each of the radio broadcasting reception devices described above may be a mobile radio broadcasting reception device such as a radio broadcasting reception device installed in a vehicle or a radio broadcasting reception device installed in a portable terminal.
According to aspects of the present invention, in a case where the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, switching of the audio to be output from the reception target broadcasting service to the alternative broadcasting service may be performed quickly with a cross-fade of a short duration, and in a case where the reception target broadcasting service and the alternative broadcasting service are not broadcasting services adhering to the same broadcasting standard, switching of the audio to be output from the reception target broadcasting service to the alternative broadcasting service may be performed gradually with a cross-fade of a longer duration.
In this case, if the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, the difference in sound quality of output audio between the respective broadcasting services, and any difference in volume can be expected to be small. Therefore, the listener can be spared the annoyance of rapid changes in volume and sound quality by a rapid cross-fade being performed between program content. In addition, the time period in which the audio reception quality of the reception target broadcasting service deteriorates can be minimized.
Meanwhile, in a case where the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to different broadcasting standards, it is common that the differences in the sound quality and volume between the broadcasting services are large. Therefore, the listener can be spared the annoyance of rapid changes in volume and sound quality by a gradual cross-fade being performed between program content.
Thus, according to the present embodiment, when the reception quality of a reception target broadcasting service deteriorates, the broadcasting service can be switched as quickly as possible to a broadcasting service broadcasting the same content to minimize annoying the listener due to rapid changes in volume and sound quality.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a block diagram illustrating a configuration of a radio broadcasting reception device according to an embodiment of the present invention;
Fig. 2 is a flowchart illustrating automatic switching processing according to an embodiment of the present invention;
Fig. 3 is a block diagram illustrating a configuration of a mix section according to an embodiment of the present invention; and
Figs. 4A and 4B are views indicating operations of the automatic switching processing according to an embodiment of the present invention.

An embodiment of the present invention will be explained below.
Fig. 1 shows a configuration of a radio broadcasting reception device according to a present embodiment.
Here, the radio broadcasting reception device is a mobile radio broadcasting reception device such as a radio broadcasting reception device installed in a vehicle or a radio broadcasting reception device installed in a portable terminal. The portable terminal in which the radio broadcasting reception device is installed may be a dedicated portable radio reception terminal, or may be an arbitrary portable terminal such as a mobile phone terminal, a smart-phone, a tablet computer, or a portable music player.
As illustrated in the drawing, the radio broadcasting reception device is provided with two systems of digital radio reception section 1, two systems of analog radio reception section 2, a selector 3, a mix section 4, an amplifier 5, a speaker 6, a control section 7, a display section 8, and an operation section 9.
The digital radio reception sections 1 are reception sections that receive radio broadcasts adhering to a Digital Audio Broadcasting (DAB) standard and a DAB+ standard, which is an enhanced version of DAB, and each digital radio reception section 1 is provided with a DAB/DAB+ front-end (DAB/DAB+ F/E) 11, a DAB/DAB+ decoder 12, an audio decoder 13, and a DA converter (DAC) 14.
The analog radio reception sections 2 are reception sections that receive radio broadcasts adhering to an FM broadcasting standard, and each analog radio reception device 2 is provided with an FM front-end (FM/F/E) 21, an FM demodulation section 22, and an RDS decoder 23.
In DAB and DAB+, a plurality of services, each service corresponding to one audio broadcast, can be broadcast on a single frequency channel, and each service is identified by a service identifier SID broadcast by the service. In addition, a group of services broadcast on the same frequency channel is called an ensemble.
With such a configuration, the digital radio reception section 1 performs the following service reception operation.
During the service reception operation, the DAB/DAB+ front-end 11 of the digital radio reception section 1 receives a signal on frequency channel that has been set as a DAB/DAB+ reception channel and transmits pieces of received data to the DAB/DAB+ decoder 12. The DAB/DAB+ decoder 12 extracts a piece of audio data received by a service that has been set as a DAB/DAB+ reception service from the pieces of received data that have been received from the DAB/DAB+ front-end 11, transmits the piece of audio data to the audio decoder 13, transmits a service identifier SID received by the service, which has been set as the reception service, and transmits service linking information received from the DAB and DBA+ to the control section 7. Then, the audio decoder 13 decodes the piece of audio data, which has been transmitted from the DAB/DAB+ decoder 12, by using a decoding method corresponding to the DAB or DAB+ standard, and transmits the decoded audio data to the DA converter 14, and the DA converter 14 converts the decoded audio data to analog audio signals and outputs the analog audio signals to the selector 3. Furthermore, the DAB/DAB+ front-end 11 and the DAB/DAB+ decoder 12 notify the control section 7 of pieces of information related to the reception quality of the DAB or DAB+ service, such as the reception electric field intensity and the S/N ratio of the DAB reception channel and the error rate of the reception data.
Meanwhile, during the abovementioned service reception operation, a service that is specified in the DAB/DAB+ reception service in an ensemble specified in the DAB/DAB+ reception channel corresponds to a service of the reception operation target.
The analog radio reception section 2 performs the following station reception operation.
During the station reception operation, the FM front-end 21 of the analog radio reception section 2 receives a signal on a frequency channel that has been set as an FM reception channel and transmits the received signals to the FM demodulation section 22. The demodulation section 22 demodulates the received signals into audio signals and transmits the audio signals to the selector 3. In addition, if the received signals include data that is transmitted after being multiplexed onto audio signals by a radio data system (RDS), the FM demodulation section 22 transmits the data to the RDS decoder 23, and the RDS decoder 23 decodes the data and transmits the decoded data to the control section 7. The pieces of data that the RDS decoder 23 transmits to the control section 7 include a program identifier PI which is an identifier of a program broadcast by FM broadcast by a station corresponding to the frequency channel set as the FM reception channel, an AF list, and so on. The FM front-end 21 also notifies the control section 7 of pieces of information related to the reception quality of the FM broadcast of the FM reception channel, such as the reception electric field intensity and the S/N ratio of the FM reception channel.
Meanwhile, during the abovementioned station reception operation, a station that is specified in the FM reception service corresponds to a station of the reception operation target.
The control section 7 calculates the reception quality of the DAB or DAB+ service for which the digital radio reception section 1 performs a reception operation on the basis of the information related to service reception quality notified by the digital radio reception section 1, and calculates the reception quality of the FM broadcast for which the analog radio reception section 2 performs a reception operation on the basis of the information related to the FM broadcast reception quality notified by the FM front-end 21 of the analog radio reception section 2.
A DAB or DAB+ service and an FM station that broadcasts a program having a PI corresponding to the SID of the DAB or DAB+ service have a mutual relationship of simultaneous broadcast, and whereby the same program content is broadcast. The AF list received during an FM broadcast is a list of FM broadcast frequencies of the program with the same PI. The service linking information received in DAB or DAB+ indicates, for each program, the identifications of DAB/DAB+ services and FM broadcast stations that broadcast the program.
Consequently, for each program, the control section 7 can obtain DAB and DAB+ services and FM broadcasts of the same content, on the basis of the SIDs of the DAB and DAB+ services, PIs of the FM broadcasts, the AF lists received in the FM broadcasts, and service linking information received in DAB and DAB+.
Next, the control section 7 calculates the reception quality of a DAB or DAB+ service from the information related to the reception quality of the DAB or DAB+ service notified by the DAB/DAB+ front-end 11 and the DAB/DAB+ decoder 12 as described above.
The control section 7 also calculates the reception quality of an FM broadcast station from the information related to the reception quality of the FM broadcast on the FM reception channel notified by the FM front-end 21 as descried above.
With such a configuration of the radio broadcasting reception device, the control section 7 accepts, via the operation section 9, a user request to receive a specific broadcast service. Note that each DAB/DAB+ service and each FM broadcast station corresponds to a broadcast service.
When accepting a request for receiving a specific DAB or DAB+ service, the control section 7 switches a reception target broadcasting service to the service that is requested to be received, and when accepting a request for receiving a specific FM broadcast station, the control section 7 switches a reception target broadcasting service to the station that is requested to be received.
Next, when the reception target broadcasting service is switched according to a user request, the control section 7 sets one of the digital radio reception sections 1 to a current reception section if the switching destination is a service, then sets, as a DAB/DAB+ reception channel, a frequency channel of an ensemble including the service in the DAB/DAB+ front-end 11, and sets, as a DAB/DAB+ reception service, the service in the DAB/DAB+ decoder 12 of the current reception section, thereby causing the digital radio reception section 1 set as the current reception section to perform an operation for receiving the service. In addition, the control section 7 controls the selector 3 to output audio signals, which have been output by the DA converter 14 of the current reception section, to the mix section 4, and controls the mix section 4 to output the audio signals, which have been output by the DA converter 14 of the current reception section to the mix section 4 through the selector 3, directly to the amplifier 5. Then, the amplifier 5 amplifies the audio signals received from the mix section 4, and the speaker 6 outputs sound.
As a result, audio, which is broadcast by the DAB or DAB+ service that the user requests to receive, is output by the speaker 6.
Then, when the reception target broadcasting service is switched according to a user request, the control section 7 sets one of the analog radio reception sections 2 to a current reception section if the switching destination is an FM broadcast station, then sets, as an FM reception channel, a frequency of the FM broadcast station in the FM front-end 21 of the current reception section, thereby causing the analog radio reception section 2 set as the current reception section to perform an operation for receiving the broadcast. In addition, the control section 7 controls the selector 3 to output audio signals, which have been output by the FM demodulation section 22 of the current reception section, to the mix section 4, and controls the mix section 4 to output the audio signals, which have been output by the FM demodulation section 22 of the current reception section to the mix section 4 through the selector 3, directly to the amplifier 5. Then, the amplifier 5 amplifies the audio signals received from the mix section 4, and the speaker 6 outputs sound.
As a result, the audio, which is broadcast on the FM broadcast station that a listener requests to receive, is output to the listener by the speaker 6.
While using the current reception section to receive the reception target broadcasting service and output program content to the speaker 6, the control section 7 repeatedly performs processing to check the reception quality of each of the DAB and DAB+ services and the FM broadcasts that broadcast a program corresponding to content the same as that of the reception target broadcasting service, by using the other digital radio reception section 1, which is not set as the current reception section, and the other analog radio reception section 2, which is not set as the current reception section.
The check of the reception quality of the DAB or DAB+ service is performed by using the digital radio reception section 1, which is not set as the current reception section, to perform an operation for receiving the service for which the reception quality is to be checked, and by calculating the reception quality of the service on the basis of the information related to the reception quality of the DAB or DAB+ service notified by the DAB/DAB+ front-end 11 and the DAB/DAB+ decoder 12 of the digital radio reception section 1, which performs the operation for receiving the service for which the reception quality is to be checked, as described above. Furthermore, the check of the reception quality of the FM broadcast station is performed by using the analog radio reception section 2, which is not set as the current reception section, to perform an operation for receiving the broadcast the reception quality of which is to be checked, and by calculating the reception quality of the station on the basis of the information related to the reception quality of the FM broadcast station notified by the FM front-end 21 of the analog radio reception section 2, which performs the operation for receiving the broadcast for which the reception quality to be checked, as described above.
In addition, the control section 7 performs automatic switching processing illustrated in Fig. 2 while receiving the reception target broadcast service by using the current reception section and outputting program content to the speaker 6.
As illustrated in the drawing, in the initial automatic switching processing, the reception quality of a reception target broadcasting service is calculated (step 202). In the calculation of the reception quality of the reception target broadcasting service, if the current reception section is a digital radio reception section 1, the calculation is performed by calculating the reception quality of the service as the reception quality of the reception target broadcasting service on the basis of the information related to the reception quality of the DAB or DAB+ service notified by the DAB/DAB+ front-end 11 and the DAB/DAB+ decoder 12 of the current reception section. In the calculation of the reception quality of the reception target broadcasting service, if the current reception section is an analog radio reception section 2, the calculation is performed by calculating the reception quality of the station as the reception quality of the reception target broadcasting service on the basis of the information related to the reception quality of the FM broadcast notified by the FM front-end 21 of the current reception section.
Then, it is determined whether the calculated reception quality of the reception target broadcasting service is lower than a predetermined level (step 204), and if the reception quality is not lower than the predetermined level, the process returns to step 202. The predetermined level in this case is a level at which a predetermined margin is added to the minimum level at which the broadcast can be received properly.
Meanwhile, if the reception quality of the reception target broadcasting service is lower than the predetermined level (step 204), it is determined whether an alternative broadcasting service is available (step 206). Here, the alternative broadcasting service is set by selecting, from among DAB or DAB+ services that broadcast a program corresponding to content the same as that of the reception target broadcasting service and FM broadcast stations that broadcast a program corresponding to content the same as that of the reception target broadcasting service, alternative candidate broadcasts each having higher reception quality than the abovementioned predetermined level and higher reception quality than the reception quality of the reception target broadcasting service, and by setting an alternative candidate broadcast having the highest reception quality among the alternative candidate broadcasts as the alternative broadcasting service. Note that, if a DAB or DAB+ service is included in the alternative candidate broadcasts, the DAB or DAB+ service may be preferentially set as the alternative broadcasting service.
If there is no available alternative broadcasting service (step 206), the process returns to step 202.
Meanwhile, if an alternative broadcasting service is available (step 206), a reception section that is capable of receiving the alternative broadcasting service, out of the digital radio reception section 1 and analog radio reception section 2 other than the current reception section, is set as an alternative broadcasting service reception section, the alternative broadcasting service reception section is controlled to start receiving the alternative broadcasting service, and the selector 3 is controlled to output, in addition to the audio being output from the current reception section, the audio signals output from the alternative broadcasting service reception section to mix section 4 (step 208).
That is, if the alternative broadcasting service is a DAB or DAB+ service, one of the digital radio reception sections 1, the digital radio reception section not being set as the current reception section, is set as an alternative broadcasting service reception section, and the digital radio reception section 1, which is set as the alternative broadcasting service reception section, is controlled to start receiving the service that is set as the alternative broadcasting service, and the selector 3 is controlled to output audio signals being output from the digital radio reception section 1 that is set as the alternative broadcasting service reception section, to the mix section 4. Furthermore, if the alternative broadcasting service is an FM broadcast, one of the analog radio reception sections 2, the analog radio reception section not being set as the current reception section, is set as an alternative broadcasting service reception section, and the analog radio reception section 2, which is set as the alternative broadcasting service reception section, is controlled receiving the station that is set as the alternative broadcasting service, and the selector 3 is controlled to output audio signals being output from the analog radio reception section 2 that is set as the alternative broadcasting service reception section, to the mix section 4.
Next, it is determine whether the reception target broadcasting service and the alternative broadcasting service are the broadcasting services adhering to the same broadcasting standard (step 210). In any one of a case where both the reception target broadcasting service and the alternative broadcasting service are DAB services, a case where both the reception target broadcasting service and the alternative broadcasting service are DAB+ services, and a case where both the reception target broadcasting service and the alternative broadcasting service are FM broadcasting station, the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard.
If the reception target broadcasting service and the alternative broadcasting service are the broadcasting services adhering to the same broadcasting standard (step 210), a first time period (100 ms, for example) is set as the cross-fade time in the mix section 4 (step 212), and if the reception target broadcasting service and the alternative broadcasting service are not the broadcasting services adhering to the same broadcasting standard (step 210), a second time period (500 ms, for example), which is longer than the first time period, is set as the cross-fade time in the mix section 4 (step 214).
Then, the mix section 4 is controlled to cross-fade audio signals of the reception target broadcasting service and audio signals of the alternative broadcasting service over the set cross-fade time period (step 216). The cross-fade operation will be described later.
After the cross-fade time period has elapsed from the start of the cross-fading operation (step 218), the service or the station subjected to the reception target broadcasting service is switched to the service or the station that has been set as the alternative broadcasting service, and the current reception section is switched to the digital radio reception section 1 or the analog radio reception section 2 that has been set as the alternative broadcasting service reception section (step 220). Then, the process returns to step 202.
The above is the explanation for automatic switching processing performed by the control section 7.
Next, the cross-fading operation performed by the mix section 4 will be described below.
First, an internal configuration of the mix section 4 is illustrated in Fig. 3.
As illustrated in the drawing, the mix section 4 has two variable gain amplifiers 41, a synthesis section 42, and a mix control section 43.
Each of the two variable gain amplifiers 41 amplifies an audio signal of the corresponding system received from the selector 3 according to a gain level set by the mix control section 43 and outputs the audio signal to the synthesis section 42, which synthesizes audio signals of the two systems received from the two variable gain amplifiers 41 and outputs the synthesized signal to the amplifier 5.
With such a configuration of the mix section 4, while not performing the cross-fading operation, the mix control section 43 sets the gain of one variable gain amplifier 41, to which the audio signal of the reception target broadcasting service received from the selector 3 is input, to a predetermined standard gain Gstd and sets the gain of the other variable gain amplifier 41 to zero amplification factor (output level 0), thereby outputting to the amplifier 5 via the synthesis section 42 only the audio signals of the reception target broadcasting service, with the audio signals being amplified to the standard gain Gstd.
Note that, the variable gain amplifier 41 to which the audio signal of the reception target broadcasting service is input is determined according to the control contents sent to the selector 3 by the control section 7, and the mix control section 43 is notified by the control section 7 of the identification of the variable gain amplifier 41 to which the audio signal of the reception target broadcasting service is input.
Meanwhile, when the mix section 43 is instructed by the control section 7 to start the cross-fading operation, the mix control section 43 performs the cross-fading operation to cross-fade the audio signals of the reception target broadcasting service input by the selector 3 with the audio signals of the alternative broadcasting service within the set cross-fade time.
That is, as illustrated in Fig. 4A, when the start of cross-fading operation is instructed, the mix control section 43 gradually reduces the gain of the variable gain amplifier 41 to which the audio signal of the reception target broadcasting service output by the current reception section is received from the selector 3, from the standard gain Gstd to zero amplification factor over the time period of time Tbl, which is set as the cross-fade time, while gradually increasing the gain of the variable gain amplifier 41 to which the audio signal of the alternative broadcasting service output by the alternative broadcasting service reception section is received from the selector from zero amplification factor to the standard gain Gstd over the time period of time Tbl, which is set as the cross-fade time. Next, until the reception target broadcasting service is switched to a service or a station that is set as the alternative broadcasting service, the gains of the respective variable gain amplifiers 41 are maintained as part of the cross-fading operation. Note that, when the cross-fading operation is completed, the alternative broadcasting service becomes the new reception target broadcasting service, and therefore the gains of the respective variable gain amplifiers 41 are maintained in the same state as they were when the cross-fading operation was completed.
Note that, the variable gain amplifier 41 to which the audio signal of the reception target broadcasting service is input and the variable gain amplifier 41 to which the audio signal of the alternative broadcasting service is input are determined according to the control contents sent to the selector 3 by the control section 7, and the mix control section 43 is notified by the control section 7 of the identification of the variable gain amplifier 41 to which the audio signal of the reception target broadcasting service is input and the identification of the variable gain amplifier 41 to which the audio signal of the alternative broadcasting service is input.
With the abovementioned operations of the mix section 4, the audio output by the speaker 6 is gradually cross-fade from the audio of the reception target broadcasting service to the audio of the alternative broadcasting service over the time period Tbl, which has been set as the cross-fade time.
As described above, if the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, the first time period (100 ms, for example), which is relatively short, is set as the cross-fade time, as illustrated in Fig. 4A. If the reception target broadcasting service and the alternative broadcasting service are not broadcasting services adhering to the same broadcasting standard, the second time period (500 ms, for example), which is relatively long, is set as the cross-fade time, as illustrated in Fig. 4B.
Therefore, in a case where the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, switching of the audio to be output by the speaker 6 from the reception target broadcasting service to the alternative broadcasting service is performed quickly with a cross-fade of a short duration, and in a case where the reception target broadcasting service and the alternative broadcasting service are not broadcasting services adhering to the same broadcasting standard, switching of the audio to be output from the speaker 6 from the reception target broadcasting service to the alternative broadcasting service is performed gradually with a cross-fade of a longer duration.
If the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, such as in a case where both services are DAB services, DAB+ services, or FM broadcast stations, the difference in sound quality of output audio between the respective broadcasting services, and any difference in volume can be expected to be small. Therefore, as in the case of the present embodiment, in a case where the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to the same broadcasting standard, the listener can be spared the annoyance of rapid changes in volume and sound quality by a rapid cross-fade being performed between program content. In addition, the time period in which the audio reception quality of the reception target broadcasting service deteriorates can be minimized.
In a case where the reception target broadcasting service and the alternative broadcasting service are broadcasting services adhering to different broadcasting standards, such as in a case of a DAB service and a DAB+ service, a case of a DAB service and an FM broadcast station, a case of a DAB+ service and an FM broadcast station, a case of a DAB+ service and a DAB service, a case of an FM broadcast service and a DAB service, and a case of an FM broadcast service and a DAB+ service, it is common that the differences in the sound quality and volume between the broadcasting services are large. Therefore, with respect to the present embodiment, in a case where the reception target broadcasting service and the alternative broadcasting service are not broadcasting services adhering to the same broadcasting standard, the listener can be spared the annoyance of rapid changes in volume and sound quality by a gradual cross-fade being performed between program content.
Thus, according to the present embodiment, when the reception quality of a reception target broadcasting service deteriorates, the broadcasting service is switched as quickly as possible to a broadcasting service broadcasting the same content to minimize annoying the listener due to rapid changes in volume and sound quality.
Note that, in the embodiment described above, each digital radio reception section 1 receives both DAB and DAB+ services, but may be configured to receive either DAB or DAB+ service. In addition, in the abovementioned embodiment, automatic switching processing may be configured so as not to perform switching of a reception target broadcasting service between FM broadcast stations.

Claims

A radio broadcasting reception device capable of receiving a plurality of radio broadcasts adhering to different broadcasting standards comprising:
a reception state detection section for detecting a reception quality of a currently received broadcasting service which is a broadcasting service being received and the sound of which is being output; and

a broadcasting service switching section for switching from a switching source broadcasting service, which is the currently received broadcasting service, to a switching destination broadcasting service, which is a broadcasting service of which the content is the same as that of the currently received broadcasting service and the reception quality of which is good, when the reception quality of the currently received broadcasting service deteriorates,

wherein the broadcasting service switching section includes

a cross-fade time setting section that sets a cross-fade time to a first time period when the switching source broadcasting service and the switching destination broadcasting service are of a same broadcasting standard, and sets a cross-fade time to a second time period, which is longer than the first time period, when the switching source broadcasting service and the switching destination broadcasting service are of different broadcasting standards, and

a mix section that performs switching from the switching source broadcasting service to the switching destination broadcasting service in such a manner that the mix section starts to receive the switching destination broadcasting service while still receiving the switching source broadcasting service, and outputs a sound to be output by cross-fading a sound signal of the switching source broadcasting service with a sound signal of the switching destination broadcasting service in such a manner that the switching is performed gradually over the time period set as the cross-fade time.
The radio broadcasting reception device according to Claim 1,
wherein the plurality of different broadcasting standards include DAB and FM broadcasts.
The radio broadcasting reception device according to Claim 1,
wherein the plurality of different broadcasting standards include DAB+ and FM broadcasts.
The radio broadcasting reception device according to Claim 1,
wherein the plurality of different broadcasting standards include DAB and DAB+ broadcasts.
The radio broadcasting reception device according to Claim 1,
wherein the plurality of different broadcasting standards include DAB, DAB+ and FM broadcasts.
A radio broadcasting reception device capable of receiving digital radio broadcasts and analog radio broadcasts comprising:
a reception state detection section for detecting a reception quality of a currently received broadcasting service which is a broadcasting service being received and the sound of which is being output; and

a broadcasting service switching section for, if the currently received broadcasting service is a broadcasting service of a digital radio broadcast, switching from a switching source broadcasting service, which is the currently received broadcasting service, to a switching destination broadcasting service, which is a broadcasting service of which the content is the same as that of the currently received broadcasting service and the reception quality of which is good, when the reception quality of the currently received broadcasting service deteriorates,

wherein the broadcasting service switching section includes

a cross-fade time setting section that sets a cross-fade time to a first time period when the switching destination broadcasting service is a broadcasting service of digital radio broadcasting, and sets a cross-fade time to a second time period, which is longer than the first time period, when the switching destination broadcasting service is a broadcasting service of analog radio broadcasting, and

a mix section that performs switching from the switching source broadcasting service to the switching destination broadcasting service in such a manner that the mix section starts to receive the switching destination broadcasting service while still receiving the switching source broadcasting service, and outputs a sound to be output by cross-fading the sound of the switching source
broadcasting service with the sound of the switching destination broadcasting service in such a manner that the switching is performed gradually over the time period set as the cross-fade time.
The radio broadcasting reception device according to Claim 6,
wherein the digital radio broadcast is a DAB broadcast and the analog radio broadcast is an FM broadcast.
The radio broadcasting reception device according to Claim 6,
wherein the digital radio broadcasting is a DAB+ broadcast and the analog radio broadcasting is an FM broadcast.
The radio broadcasting reception device according to one of Claims 1 to 8,
wherein the radio broadcasting reception device is installed in a mobile body or a portable terminal.
A method for switching reception broadcasting services to switch to a broadcast which is received and a sound of which is output by a radio broadcasting reception device capable of receiving a plurality of radio broadcasts adhering to different broadcasting standards comprising:
a reception state detection step of detecting a reception quality of a currently received broadcasting service which is a broadcasting service being received and the sound of which is being output; and

a broadcasting service switching step of switching from a switching source broadcasting service, which is the currently received broadcasting service, to a switching destination broadcasting service, which is a broadcasting services of which the content is the same as that of the currently received broadcasting service and the reception quality of which is good, when the reception quality of the currently received broadcasting service deteriorates,

wherein, in the broadcasting service switching step,

a cross-fade time is set to a first time period when the switching source broadcasting service and the switching destination broadcasting service are of a same broadcasting standard, and a cross-fade time is set to a second time period, which is longer than the first time period, when the switching source broadcasting service and the switching destination broadcasting service are of different broadcasting standards, and

switching from the switching source broadcasting service to the switching destination broadcasting service is performed in such a manner that a sound to be output is output by cross-fading the sound of the switching source broadcasting service with the sound of the switching destination broadcasting service in such a manner that the switching is performed gradually over the time period set as the cross-fade time.