KR20130010525A - Dual digital audio broadcasting receiver and service linking method using thereof - Google Patents

Abstract

PURPOSE: A dual DAB receiving device and a service linking method using the same are provided to implement seamless DAB(Digital Audio Broadcasting) regardless of a moving region of a vehicle. CONSTITUTION: An audio processing unit(224) extracts first and second audio signals by demodulating and decoding first and second digital audio signals. A handover determining unit(226) determines whether a vehicle of a listener enters a handover area. The handover determining unit supplies a service by changing a first frequency into a second frequency. An audio output unit(230) outputs the first and second voice signals. [Reference numerals] (221a) First high-frequency processing unit; (221b) Second high-frequency processing unit; (222a) First base-band processing unit; (222b) Second base-band processing unit; (224) Audio processing unit; (225) Storage unit; (226) Handover determining unit; (230) Audio output unit

Description

Dual digital audio broadcasting receiver and service linking method using same {DUAL DIGITAL AUDIO BROADCASTING RECEIVER AND SERVICE LINKING METHOD USING THEREOF}

The present invention relates to a dual digital audio broadcasting receiver, and more particularly, a first and a second front end unit for receiving and converting each of the first and second channel signals into first and second digital audio signals. 1, by implementing a service linking by providing a handover determination unit for frequency conversion in the handover area where the second channel signal is simultaneously caught, seamless regardless of the moving area of the vehicle (seamless) The present invention relates to a dual digital audio broadcasting receiver for implementing digital audio broadcasting (DAB).

In anticipation of Digital Audio Broadcasting (DAB) and strong government intentions, the broadcasting market in the future will radically shift from analog radio broadcasting (FM / AM) to digital audio broadcasting (DAB).

This means that digital audio broadcasting (DAB) eliminates the white noise and noise generated by conventional analog radio broadcasting (FM / AM), noise with better sound quality (CD quality sound) and higher channel count (up to 5.1 channels). This is because it has the advantage of being accessible to consumers without.

As a result, the digital audio broadcasting (DAB) market will become larger and larger, and research on digital audio broadcasting (DAB) has been conducted since 1990, and there are many broadcasting networks and products to date.

Among them, a technology that has been mainly researched is a service linking technology that allows a listener to listen to the same broadcast program seamlessly while constantly changing frequency when moving through a vehicle.

1 illustrates a conventional DAB receiving apparatus.

Referring to FIG. 1, a conventional DAB receiving apparatus 100 includes a front end unit 123 including an antenna 110, a high frequency processor 121, and a baseband processor 122, an audio processor 124, and a storage unit. DAB full module (Digital Audio Broadcasting Full Module, 120) having the 125 and the audio output unit 130 is provided.

Hereinafter, an operation of implementing digital audio broadcasting (DAB) by the prior art will be briefly described.

The antenna 110 receives a digital audio broadcasting (DAB) signal sent by the transmitter.

The high frequency processor 121 receives an analog high frequency (RF) signal received from the antenna 110 and converts the corresponding channel signal into an analog base band according to a user's selection.

The baseband processor 122 outputs a digital audio signal by analog-to-digital (A / D) conversion of the analog baseband signal.

The audio processor 124 receives the digital audio signal converted by the front end unit 123 and demodulates and decodes the digital audio signal to extract a voice signal.

The audio output unit 130 outputs a voice signal processed by the audio processor 124 as an audible sound that can be heard by the listener.

However, the prior art has the following problems when implementing digital audio broadcasting (DAB).

That is, the conventional DAB receiving apparatus 100 has no choice but to listen to only one frequency in a single module form having one front end unit 123 including the high frequency processor 121 and the baseband processor 122, and the FIC. When following the DAB service following using only the Fast Information Channel information, when the channel signal of the selected frequency is cut off completely, a mute occurs for at least 3 seconds to switch to the associated frequency. There was a problem that a listener cannot listen to a seamless broadcast.

The present invention has been made in an effort to provide a dual digital audio broadcast receiving apparatus for implementing seamless digital audio broadcasting (DAB) regardless of a moving region of a vehicle.

According to an aspect of the present invention, there is provided a dual digital audio broadcast receiving apparatus comprising: an antenna for receiving a digital audio broadcast (DAB) signal sent from a transmitter; First front-end unit for receiving a high-frequency (RF) signal of the analog form received from the antenna to convert a first channel signal having a first frequency band to be used as the first channel selection of the listener to a first digital audio signal ; A second front end unit for receiving an analog high frequency (RF) signal received from the antenna and converting a second channel signal having the second frequency band into a second digital audio signal; An audio processor configured to receive the first and second digital audio signals converted by the front end unit and to demodulate and decode the first and second voice signals, respectively, to extract the first and second voice signals; It is determined whether the vehicle of the listener enters the handover area where the first frequency and the second frequency are simultaneously detected, and if so, the handover determination unit for changing the first frequency from the first frequency to the second frequency to provide a service. ; And an audio output unit configured to output the first and second voice signals as an audible sound that can be heard by a listener.

In addition, the service linking method using a dual digital audio broadcast receiving apparatus according to the present invention for achieving the above technical problem, the first step of preparing for digital audio broadcasting (DAB) channel selection; Selecting a first frequency to be used as a first channel tuning of the listener in the first front-end unit, converting a received analog channel first channel signal into a first digital audio signal and then broadcasting to the listener at the first frequency; A second step of searching for a second frequency having a band capable of listening to the same digital audio broadcasting (DAB) service as the first frequency in a second front end unit; A fourth step of storing the second frequency and preparing to provide a broadcast service to a listener at a second frequency by converting the received analog second channel signal into a second digital audio signal; A fifth step of determining whether a vehicle of a listener enters a handover area where the first frequency and the second frequency are simultaneously detected; And returning to the second step if it is determined that the vehicle has not yet entered the handover area in the fifth step, and when determining that the vehicle has entered the handover area in the fifth step, A sixth step of changing service from frequency to the second frequency is provided.

The present invention has the technical effect of allowing a listener of a vehicle to listen to seamless digital audio broadcasting (DAB) regardless of the area of movement of the vehicle.

1 illustrates a conventional DAB receiving apparatus.
2 illustrates a dual DAB receiving apparatus according to the present invention.
3 is a flowchart illustrating a service linking method using a dual DAB receiving apparatus according to the present invention.
FIG. 4 is a graph illustrating a method of implementing service linking by changing a frequency in a handover region when the dual DAB receiving apparatus of the present invention is used.
Figure 5 shows a first embodiment implemented by the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 illustrates a dual DAB receiving apparatus according to the present invention.

2, the dual DAB receiving apparatus 200 according to the present invention includes an antenna 210, a DAB full module 220, and an audio output unit 230.

The antenna 210 receives a digital audio broadcasting (DAB) signal sent from a transmitter.

The DAB full module 220 includes a first front end unit 223a, a second front end unit 223b, an audio processor 224, a storage unit 225, and a handover determination unit 226.

Hereinafter, the first front end unit 223a and the second front end unit 223b include a dual audio receiving digital audio broadcasting (DAB) signal and a service implemented by the handover determination unit 226. Describes the linking principle.

The first front end unit 223a includes a first high frequency processor 221a and a first baseband processor 222a.

The first high frequency processor 221a receives an analog high frequency (RF) signal received from the antenna 210 and outputs a first channel signal having a first frequency band according to the first channel selection of the listener. band).

The first baseband processor 222a outputs a first digital audio signal by analog-to-digital (A / D) converting the analog baseband signal.

The second front end unit 223b includes a second high frequency processor 221b and a second baseband processor 222b.

In the same manner as the first front end unit 223a, the second high frequency processor 221b receives an analog high frequency (RF) signal received from the antenna 210 and uses a second frequency to be used after the first null tuning. A second channel signal having a band is converted into an analog base band.

The second baseband processor 222b outputs a second digital audio signal by analog-to-digital (A / D) converting the analog baseband signal.

The audio processor 224 receives the first and second digital audio signals converted by the first and second front end units 223a and 223b to demodulate and decode the first and second voices. Extract each of the signals.

In this case, the audio processor 224 uses MPEG-2 AAC (Advanced Audio Coding) or MPEG-4 AAC (Advanced Audio Coding) as an audio codec. The reason for using MPEG-2 AAC is that MPEG-2 AAC has compressed audio data and saves data in units of frames, which can reduce capacity by up to 30 percent and provide better sound quality. Because.

The storage unit 225 is a temporary storage space for demodulating and decoding the audio processing unit 224 and performing decoding operations. The storage unit 225 and the first and second front end units 223a may be used. And a flash memory for storing the first and second digital audio signals converted in operation 223b, various channel lists, and the like.

The handover determination unit 226 determines whether the vehicle has entered the handover region, and if it is determined that the vehicle has entered the handover region, it is used before entering the handover region. Service linking is implemented by changing the first frequency to the second frequency searched by the second front end unit 223b.

In this case, the handover region refers to an area where service linking is possible by simultaneously catching a broadcast service transmitted at a first frequency and a broadcast service transmitted at a second frequency.

In this case, the handover determination unit 226 continuously monitors the propagation intensity of the first and second channel signals input to the first and second front end units 223a and 223b to determine whether a handover is necessary. .

That is, the handover determination unit 226 is a case where the propagation intensity of the first channel signal input to the first front end unit 223a has a threshold value less than or equal to a predetermined threshold value and lasts for a specified time (for example, 1 minute), and If the propagation intensity of the second channel signal inputted to the second front end unit 223b is longer than a predetermined threshold and lasts for a predetermined time (for example, one minute), a handover is necessary. I think that.

The audio output unit 230 outputs the first and second voice signals processed by the audio processor 224 as audible sound that can be heard by the listener, and a speaker is used as the output device.

3 is a flowchart illustrating a service linking method using a dual DAB receiving apparatus according to the present invention.

Hereinafter, a service linking method using a dual DAB receiving apparatus according to the present invention will be described with reference to FIGS. 3 and 2.

First, a first step S10 of preparing digital audio broadcasting (DAB) channel selection is provided.

In this case, a listener driving a vehicle prepares a digital audio broadcasting (DAB) channel to be tuned for operation by operating an audio system installed in the vehicle.

The first front end unit 223a selects a first frequency that the listener wants to listen to, converts the received analog first channel signal into a first digital audio signal, and then broadcasts the digital audio to the listener at the first frequency (DAB). ) A second step (S20) of providing a service.

In this case, the listener continues to receive the broadcast service of the first frequency selected by the first front end unit 223a until the vehicle is moved to a specific region and broadcast is cut off.

The second front end unit 223b has a third step S30 of searching for a second frequency having a band capable of listening to the same digital audio broadcasting (DAB) service as the first frequency.

Here, the second frequency refers to a frequency value near the first frequency band in which the same broadcast program transmitted at the first frequency can be heard.

A fourth step S40 of storing the retrieved second frequency and converting the received analog second channel signal into a digital audio signal and preparing to provide a digital audio broadcasting (DAB) service to the listener at the second frequency; .

And a fifth step S50 of determining whether the vehicle has entered a handover region in which the first frequency and the second frequency are simultaneously caught.

 If it is determined in step 5 (S50) that the vehicle has not yet entered the handover region, the vehicle returns to step 2 (S20) to return to step 2 (S20) to step 4 (S40). ) Is performed the same.

On the other hand, when it is determined that the vehicle enters the handover region in the fifth step S50, the sixth step of changing from the first frequency to the second frequency to provide a digital audio broadcasting (DAB) service (S60). Is implemented.

Hereinafter, referring to FIG. 4, a principle of providing a seamless digital audio broadcasting (DAB) service through frequency change in a handover region will be described.

FIG. 4 is a graph illustrating a method of implementing service linking by changing a frequency in a handover region when the dual DAB receiving apparatus of the present invention is used.

Referring to FIG. 4, when the vehicle moves from the CELL1 region to the CELL2 region, the graph shows the change in the radio wave intensity of the signal of Service A transmitted from the CELL1 region and Service B transmitted from the CELL2 region. In this case, the broadcast service Service A and Service B have the same broadcast ID, so that the listener can listen to the same program.

In this case, the propagation intensity of the signal of Service A tends to decrease gradually as the vehicle moves from CELL1 to CELL2.

On the other hand, the propagation intensity of the signal of Service B tends to increase as the vehicle moves from the CELL1 area to the CELL2 area.

Meanwhile, in FIG. 4, the hatched handover region is a region d1, d2, d3, and d4 where the signal of Service A in the CELL1 region and the Service B signal in the CELL2 region are simultaneously detected to enable service linking. Indicates.

 Here, the propagation intensity of Service A and Service B according to each region of the handover region is shown. In the d1 region, the propagation intensity of Service A is greater than that of Service B, and in the d2 region, the propagation intensity of Service A is It is the same as the propagation intensity of Service B, and has a distribution in which the propagation intensity of Service B becomes larger than that of Service A toward the d3 and d4 regions.

At this time, whether the vehicle approaches the handover region indicates whether the intensity of the intensity of the signal of the received service A is kept below a certain level and the intensity of the intensity of the signal of the received service B. It is determined whether is maintained for a certain time over a certain criterion.

3 and 4, a process of listening to a digital audio broadcast (DAB) seamlessly by a listener of a vehicle will be described as an example.

The listener of the vehicle continuously receives the broadcast service Service A at the first frequency selected by the first front end unit 223a until d1 immediately before entering the handover region in CELL1.

Meanwhile, the second front end unit 223b searches for all audible frequencies until d1 immediately before entering the handover region, stores the retrieved second frequencies, and stores the received analog second channel signals. 2 Convert to a digital audio signal and prepare to provide a digital audio broadcasting (DAB) service to a listener at a second frequency.

When the vehicle reaches the d2 region of the handover region, that is, the region where the radio wave intensity of Service A and the radio wave intensity of Service B intersect with the same value, the broadcast service having the first frequency (Service A) Switch to a broadcast service (Service B) having two frequencies.

In this case, the digital audio broadcasting (DAB) service can be provided by changing from the first frequency to the second frequency at any point of d1, d2, d3, and d4 belonging to the handover region, but the listener is in the best state. Of course, you must choose a point where you can listen to the broadcast.

Accordingly, the present invention implements service linking in a handover region by using a dual DAB receiving apparatus installed in a vehicle, so that a listener can seamlessly digital audio broadcast regardless of the moving region of the vehicle. (DAB) to listen to the service.

Figure 5 shows a first embodiment implemented by the present invention.

Referring to FIG. 5, when the vehicle moves from the region A to the region B, the radio wave strength that can be received in region A is 12B (225.648 MHz)> 12C (227.360 MHz)> 12A (223.936 MHz), and the radio wave can be received in region B. The intensity is 12C (227.360 MHz)> 12C (227.360 MHz)> 12A (223.936 MHz)> 12B (225.648 MHz).

In this case, when the listener is listening to 12B (225.648 MHz) having the best reception strength in region A and then moves to region B, the listener may use service linking in the handover region using dual DAB receivers installed in the vehicle. By implementing service linking, it is possible to listen to seamless broadcasts by changing to 12C (227.360MHz), which has the best reception strength in region B.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention.

110, 210: Antenna
120, 220: DAB Full Audio Broadcasting Full Module
121: high frequency processing unit
221a: first high frequency processor 221b: second high frequency processor
122: baseband processing unit
222a: first baseband processor 222b: second baseband processor
123: front end unit
223a: first front end unit 223b: second front end unit
124, 224: audio processing unit 125, 225: storage unit
226: handover determination unit 130, 230: audio output unit

Claims (8)

An antenna for receiving a digital audio broadcasting (DAB) signal sent by a transmitter;
First front-end unit for receiving a high-frequency (RF) signal of the analog form received from the antenna to convert a first channel signal having a first frequency band to be used as the first channel selection of the listener to a first digital audio signal ;
A second front end unit for receiving an analog high frequency (RF) signal received from the antenna and converting a second channel signal having the second frequency band into a second digital audio signal;
An audio processor configured to receive the first and second digital audio signals converted by the first and second front end units, and to demodulate and decode the first and second digital audio signals, respectively, to extract the first and second voice signals;
It is determined whether a vehicle of a listener enters a handover area where the first frequency and the second frequency are simultaneously detected, and when the vehicle is entered, a handover determination unit for changing a service from the first frequency to the second frequency to provide a service. ; And
And an audio output unit configured to output the first and second voice signals as an audible sound that can be heard by a listener. The method of claim 1, wherein the first front end unit,
A first high frequency processor for converting the first channel signal into an analog base band; And
And a first baseband processor for analog-to-digital (A / D) converting the analog baseband signal and outputting the analog baseband signal as a first digital audio signal. The method of claim 1, wherein the second front end unit,
A second high frequency processor for converting the second channel signal into an analog base band; And
And a second baseband processor for analog-to-digital (A / D) converting the analog baseband signal and outputting the analog baseband signal as a second digital audio signal. The method of claim 1, wherein the second frequency is,
And a frequency value near a first frequency band for listening to the same program transmitted at the first frequency. The method of claim 1, wherein the audio processor,
Dual digital audio broadcast receiving apparatus characterized by using MPEG-2, MPEG-4 AAC (Advanced Audio Coding) as an audio codec (codec). The method of claim 1,
An SDRAM as a temporary storage space for demodulation and decoding in the audio processor; And
And a storage unit having a flash memory for storing the first and second digital audio signals and the channel list converted by the first and second front end units. . A first step of preparing digital audio broadcasting (DAB) channel selection;
Selecting a first frequency to be used as a first channel tuning of the listener in the first front-end unit, converting a received analog channel first channel signal into a first digital audio signal and then broadcasting to the listener at the first frequency; Providing a second step;
Searching for a second frequency having a band in which a second front end unit can listen to the same digital audio broadcasting (DAB) service as the first frequency;
A fourth step of storing the second frequency and preparing to provide a broadcast service to a listener at a second frequency by converting the received analog second channel signal into a second digital audio signal;
A fifth step of determining whether a vehicle of a listener enters a handover area where the first frequency and the second frequency are simultaneously detected; And
If it is determined in step 5 that the vehicle has not yet entered the handover area, the process returns to the second step,
And if it is determined that the vehicle enters the handover region in the fifth step, changing the service from the first frequency to the second frequency; and using the dual digital audio broadcasting receiver. Linking method. The method of claim 7, wherein determining whether to enter the handover area,
It is determined by whether the intensity of the radio wave intensity for the signal of the first frequency is kept below a predetermined reference for a certain time and whether the intensity of the wave intensity for the signal of the second frequency is maintained for a certain time or more over a predetermined reference. A service linking method using a dual digital audio broadcast receiving apparatus.

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