KR0171739B1 - Auto-selecting apparatus and method of frequency of a car audio - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tuning apparatus and method for generating noise of car audio, comprising: an antenna mounted at a predetermined position of an automobile and receiving radio waves; In the car audio having an IF circuit for detecting the intermediate frequency band of the input frequency, and an amplifier for amplifying the input voice signal and outputting through the speaker, outputs a voltage which is connected to one side of the IF circuit in proportion to the electric field strength A control unit for determining the noise inclusion degree of the frequency received by the output signal of the SM terminal, and tuning the other frequency if it is higher than a set value, and indicating that another frequency is tuned by receiving the control signal output from the control unit. The display unit is tuned by the driver when the car is driving. The frequency input by measuring the voltage drop number using the SM terminal to determine the noise level, if the noise is determined to be tuned automatically to the noise-free frequency.

Description

Frequency automatic tuning device for car audio and its method

The present invention relates to a frequency automatic tuning device for car audio and a method thereof, and more particularly, when the electric field strength of a radio wave is weak or passes through a mountain area and a building area while a driver is listening to a broadcast signal through car audio. The present invention relates to a frequency automatic tuning device for car audio and a method for automatically tuning a broadcast signal of another frequency band when a noise signal is mixed.

In general, a radio broadcasting method is classified into an amplitude modulation method using an electric wave of a medium frequency band and a frequency modulation method using an electric wave of a microwave band, and the frequency modulation method has a sound quality higher than that of an amplitude modulation method. It is clean and relatively less affected by noise.

Since the frequency modulation method is strong against foreign noise and the dynamic range (difference in loudness variation) is large, the transmission frequency band is widely caught. Therefore, it can be a hi-fi broadcast or stereo broadcast with good sound quality. Almost none, but because of the use of ultra-high frequency, the straightness is strong, so the service area is not wide, and many stations need to be broadcasted nationwide, or radio waves are reflected to mountains and buildings, so if you do not pay attention to receiving only direct waves using a directional antenna, Distortion occurs and various noises may be generated when the electric field of the received radio wave is low.

In addition, the noise of the weak electric field generated by the frequency modulation method has a large number of paths reflected by SKIP noise, which is distorted due to the influence of strong electric fields and magnetic fields such as high voltage lines, and noise generated by buildings and buildings in large cities. Multipath noise generated by parallax along multiple paths at the time of output and WHITE noise which is determined as random or impulsive noise is not clearly identified.

On the other hand, automobiles face various situations due to their characteristics. Therefore, the car audio installed in the car must also output clean sound quality in a situation facing the car, so the car audio of the car must be able to provide a noise free frequency by a device that cuts out the noise band.

However, since the noise included in the frequency transmitted from the broadcasting station is generated by various causes and ambiguities as described above, it is a very difficult problem to completely block the noise.

Therefore, when most drivers generate noise at the tuned frequency, the driver operates the tuner to tune to another frequency at which the noise does not occur.

Herein, the automatic tuning method when the noise of the car audio according to the prior art will be described with reference to FIG.

1 is a flowchart illustrating an automatic tuning method in the occurrence of noise of car audio according to the prior art.

In the conventional car audio tuning method of the car, as shown in FIG. 1, when the driver listening to the audio signal output at the frequency induced from the antenna generates a lot of noise, it is determined whether the frequency tuning key has been operated. A preset frequency output step (S20) for outputting a broadcast channel of a currently tuned frequency when the frequency preset key is not operated through the frequency presetting check step (S10) and the frequency presetting check step (S10); When the frequency tuning key is operated through the tuning selection step, a frequency tuning operation step (S30) searches for adjacent broadcast signals and jumps to the tuning frequency output step.

As can be seen through the steps described above, in the conventional method of tuning car audio mounted in a car, the driver listens to a voice signal output from a speaker and uses a direct frequency tuning key to tune to another frequency when a noise signal is mixed. Mechanical tuning is performed to perform the tuning operation.

Therefore, when a car moves to a noisy metropolitan area or a mountainous area, the driver has to tune a frequency from time to time, which not only has the trouble of maneuverability but also has a big disadvantage in driving.

Accordingly, the present invention has been made to solve the above problems, and the object of the present invention is to provide a high quality broadcast signal without operating a separate key input unit to select a desired broadcast signal while the vehicle is in operation. The present invention provides an automatic frequency tuning device for car audio and a method for automatically tuning a broadcast signal of a different frequency band to be listened to.

1 is a flowchart for explaining a method for automatically tuning frequency of car audio according to the prior art.

2 is a block diagram showing an automatic frequency tuning device for car audio according to the present invention.

3 is a flowchart illustrating a method for automatically tuning frequency of car audio according to the present invention.

4 is a waveform diagram showing the voltage drop of the SM terminal when the noise of the car audio according to the present invention.

* Explanation of symbols for main parts of the drawings

10 antenna 20 tuner unit

30: IF circuit part 31: SM terminal

40: MPX section 50: amplification section

60: speaker 70: control unit

80: key input unit 90: display unit

S101: Step of confirming key input operation S102: Step of selecting desired frequency

S103: display step display step S104: broadcast signal output step

S105: time counting step S106: voltage drop count detection step

S107: Step of checking voltage drop count S108: Step of selecting another frequency

S109: jump step S110: reduction step

The present invention for achieving the above object is a tuner unit for selecting a desired frequency signal from the high-frequency signal derived from the antenna, an IF circuit unit for converting the desired frequency signal selected by the tuner unit into an intermediate frequency audio signal, IF circuit unit An automatic frequency tuning device for car audio, comprising: an amplifying unit configured to amplify an intermediate frequency audio signal and output the same through a speaker, wherein the SM produces mass output signals proportional to the electric field strength of the intermediate frequency audio signal converted by the IF circuit unit. (Signal Meter) and a control unit for retrieving the output signal of the SM terminal to determine the degree of inclusion of the noise contained in the intermediate frequency voice signal of the IF circuit unit, and if more than the set value, the control unit to tune to another frequency. The basic features of the technical configuration.

In addition, the present invention for achieving the above object, the key input unit operation confirmation step of confirming whether or not the key input unit of the car audio to listen to the desired broadcast signal, and the key input unit operation through the key input unit operation confirmation step If it is confirmed that the desired frequency selection step of selecting the desired frequency, and if the desired broadcast signal is selected through the desired frequency selection step, the display unit display step of displaying a frequency band on the display unit to inform the naked eye to the display unit, and the display unit A time for counting the time when the key input unit is not operated through the broadcast signal output step of performing the display step and simultaneously outputting the broadcast signal selected through the desired frequency selection step through a speaker and the key input unit operation checking step. Counting stage and IF circuit through SM terminal The voltage drop count detection step of measuring the voltage drop count by mass-producing the output signal proportional to the electric field strength of the intermediate frequency voice signal of the signal, and the voltage drop count detection step to determine whether the output signal voltage drop over the prescribed value When there is a voltage drop exceeding a predetermined value through the voltage drop count checking step and the voltage drop count checking step, another frequency selection step that leads to the display unit display step by selecting another frequency and the voltage drop count checking step are below the prescribed value. In the case of voltage drop, when the broadcast signal of the weak electric field flows through the mountainous area or the building area while jumping to the display unit display step and listening to the desired broadcast signal through the broadcast signal output step, the voltage drop again. Reducing the number of times including the step of checking And that made of a base characterized in that on the technical methods.

Hereinafter, a preferred embodiment of an automatic frequency tuning device for car audio and a method thereof according to the present invention will be described with reference to FIGS. 2, 3, and 4.

2 is a block diagram showing a frequency automatic tuning apparatus for car audio according to the present invention, and FIG. 3 is a flowchart illustrating a method for automatically tuning frequency of car audio according to the present invention, and FIG. 4 is a car audio according to the present invention. Is a waveform diagram to show voltage drop of SM terminal when noise occurs.

According to the present invention, an automatic frequency tuning device for car audio includes a tuner unit 20 for selecting a desired frequency signal from a high frequency signal induced from the antenna 10 as shown in FIG. An IF circuit unit 30 for converting the selected desired frequency signal into an intermediate frequency audio signal, an MPX unit 40 for adjusting stereo sound of the intermediate frequency audio signal output from the IF circuit unit 30, and the MPX unit 40 Amplification unit 60 for amplifying a stereo frequency-adjusted mid-frequency audio signal through the speaker 60 and an output proportional to the electric field strength of the intermediate frequency audio signal converted by the IF circuit unit 30. Signal value (SM) terminal 31 for mass-producing the signal, and the output signal of the SM terminal 31 is searched to determine the degree of inclusion of the noise contained in the intermediate frequency voice signal of the IF circuit unit 30, the setting value If different frequency The control unit 70 to tune in, the key input unit 80 to select a desired broadcast signal by the driver's operation, and when the desired broadcast signal is selected under the control of the control unit 70, the driver will be visually notified. And a display unit 90 for displaying the frequency band.

Referring to the operation of the automatic frequency tuning device for car audio according to the present invention having the above configuration is as follows.

First, when the driver manipulates the key input unit 80 to listen to a desired broadcast signal, the operation signal drives the tuner unit 20 through the control unit 70.

Thereafter, when the high frequency signal propagated from the broadcasting station is induced through the antenna 10, the high frequency signal is selected through the tuning process of the tuner unit 20, and only the desired frequency signal is selected. The selected desired frequency signal is converted into an intermediate frequency audio signal through the IF circuit unit 30, and then the stereo sound is adjusted while passing through the MPX unit 40 to be finally amplified by the amplifier unit 50 and simultaneously to the speaker 60. The broadcast signal is output as a broadcast signal, and the frequency band at which the broadcast signal is output is displayed through the display unit 90 to inform the driver.

Meanwhile, the SM terminal 31 connected to the IF circuit unit 30 mass-produces an output signal proportional to the electric field strength of the intermediate frequency voice signal of the IF circuit unit 30, as shown in FIG. In order to select a broadcast signal of a different frequency band, this frequency tuning method of the control unit 70 will be described with reference to FIG.

First, the controller 70 checks whether the driver manipulates the car audio key input unit 80 to listen to a desired broadcast signal (S101).

If the manipulation of the key input unit 80 is confirmed, the control unit 70 controls the tuner unit 20 to select a desired frequency derived from the antenna 10 (S102), and selects the desired frequency. When a desired broadcast signal is selected through S102, the frequency band of the broadcast signal is displayed on the display unit 90 so that the driver can check it (S103), and the broadcast signal includes the MPX unit 40 and the amplifier unit. 50, the amplified to a high quality audible sound signal via the speaker 60 is finally output (S104).

On the other hand, when the key input unit 80 is not operated, the time is counted (S105) and the output is proportional to the electric field strength of the intermediate frequency audio signal of the IF circuit unit 30 through the SM terminal 31. Obtain a signal (S106).

Thereafter, after confirming whether the output signal mass-produced from the SM terminal 31 has dropped the voltage higher than or equal to the prescribed value as shown in FIG. 4 (S107), if there is a voltage drop higher than or equal to the prescribed value, the control unit 70 commands. As a result, another frequency is selected (S108) to proceed to the display unit display step (S103).

When the voltage falls below the prescribed value through the voltage drop count checking step (S107), a jump (S109) is immediately performed to the display unit display step (S103), and the broadcast desired by the broadcast signal output step (S104). While listening to the signal, if the broadcast signal of the weak electric field flows through the mountainous region or the building area, the step S110 is continuously performed to return to the voltage drop count checking step (S107) continuously, and the driver inputs a separate key input unit. Even if the operation of 80 is not performed, the optimum broadcast signal can be received.

As described above, according to the present invention, an automatic frequency tuning device for car audio and a method thereof include: When a driver listens to a broadcast signal through car audio, the electric field strength of the radio wave is weak or passes through a mountain area and a building area. When the broadcast signal or noise signal of the weak electric field is mixed, the time is counted and the configuration is improved so that the broadcast signal of the other frequency band is automatically tuned and the desired method is selected while driving the vehicle. In order to listen to a high quality broadcast signal without operating a separate key input unit, there is an excellent effect of eliminating the risk of operation and hassle.

Claims (2)

A tuner unit 20 for selecting a desired frequency signal among the high frequency signals induced from the antenna 10, an IF circuit unit 30 for converting the desired frequency signal selected by the tuner unit 20 into an intermediate frequency audio signal, and an IF In the automatic audio frequency tuning device of the car audio comprising an amplifier 50 for amplifying the intermediate frequency audio signal of the circuit unit 30 through the speaker 60, the intermediate converted by the IF circuit unit 30 The SM (Signal Meter) terminal 31 for producing an output signal proportional to the electric field strength of the frequency audio signal and the output signal of the SM terminal 31 are searched and included in the intermediate frequency audio signal of the IF circuit unit 30. And a control unit (70) which tunes to another frequency if it is greater than or equal to a predetermined value after determining the degree of inclusion of the noise. Operation of the key input unit 80 through a key input unit operation confirmation step (S101) and a key input unit operation confirmation step (S101) for confirming whether the car audio key input unit 80 has been operated to listen to a desired broadcast signal. If it is confirmed that the desired frequency selection step (S102) for selecting the desired frequency and the desired frequency signal is selected through the desired frequency selection step (S102), the frequency band is displayed on the display unit 90 to inform the driver visually. A broadcast signal output step (S104) which is performed simultaneously with the display unit display step (S103) and the display unit display step (S103) to display and outputs the broadcast signal selected through the desired frequency selection step (S102) through the speaker 60. And a time counting step (S105) of counting time when the key input unit 80 is not operated through the key input unit operation checking step (S101), and the SM terminal 31. Through the voltage drop count detection step (S106) and the voltage fall count detection step (S106) to measure the voltage drop count by mass-producing the output signal proportional to the electric field strength of the intermediate frequency voice signal of the IF circuit unit 30 through The display unit display step by selecting a different frequency when there is a voltage drop count check step (S107) and a voltage drop count check step (S107) to check whether the output signal has a voltage drop exceeding a predetermined value. (S109) and jumping to the display unit display step (S103) immediately when the voltage falls below a predetermined value through another frequency selection step (S108) and the voltage drop count checking step (S107) which leads to (S103). While listening to the desired broadcast signal through the broadcast signal output step (S104), a broadcast signal of a weak electric field may be introduced via a mountainous area or a building area. Right back automatic channel selection method for a car audio frequency comprising the step (S110) for reducing the voltage to determine the number of times the falling step (S107).