JPH04341022A - Radio receiver with network follow function mounted with diversity - Google Patents

Abstract

PURPOSE:To realize a radio receiver provided with two tuners and having the diversity function and the network follow function. CONSTITUTION:Tuners 1,2 implement channel selection tuning, and a diversity section 3 detects the levels of multi-path of the tuners 1, 2 and compares them. A switch 4 selects a tuner whose level is smaller than that of the other tuner alternatively. One reception frequency of the tuners 1,2 is fixed and the other reception frequency is changed to compare both contents of audio signals. When the content of the audio signal is coincident, a voice comparator section 6 uses the switch 4 to select a tuner whose electric field strength is larger. The switch 8 selects the voice comparison section 6 and the diversity section 3 alternatively to select the switch 4. By such constitution, both the diversity function and the network follow function are alternatively enhanced by using only the two tuners.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a radio that is mounted on a mobile body and has a diversity function of reproducing the output of the received signal with less multipath using two antennas. The present invention relates to a radio having a network follow function that receives different signals using two tuners and reproduces output with a large electric field strength.

In particular, the present invention refers to a radio having two tuners and having both diversity and network following functions.

0003

2. Description of the Related Art FIG. 5 is a diagram showing a conventional diversity radio. Note that similar components are represented by the same reference numbers or symbols throughout the drawings. The configuration in this figure includes detecting the multipath level of the first tuner 1 and second tuner 2 that tune to the same station, and the first tuner 1 and the second tuner 2 that tune to the same station. and the diversity section 3 to be compared, and the two tuners (1,
Among 2), based on the detection results of the diversity section 3,
a switch section 4 that selectively selects one with a low multipath level; a diversity control section 5 that causes the first tuner 1 and the second tuner 2 to select the same station;
an audio amplifier 1 that amplifies the output of one of the first and second tuners (1, 2) selected by the switch 4;
00, a speaker 101 for reproducing the output of the audio amplifier 100 into sound, and an antenna 102 connected to the first and second tuners (1, 2), respectively. The configuration of the diversity section 3 will be explained in the embodiment section.

According to the present diversity unit 3, distortion that occurs in the demodulated output by receiving radio waves in which reflected waves from mountains, buildings, etc. are added to the direct waves arriving from the transmitting antenna, that is, distortion that is caused by multipath, is eliminated. The sound quality is improved by detecting this and reproducing the demodulated output of the two antennas and tuners, whichever has less distortion.

FIG. 6 is a diagram showing a conventional radio equipped with a network follower. The components in this diagram that are different from those in FIG. 5 are a voice comparison section 6 and a network follow control section 7.
It is. The audio comparing section 6 compares the audio contents of the first tuner and the second tuner 2, and if the audio contents match, it compares which of the two has a larger electric field strength of radio waves. The configuration of the audio comparison section 6 will be explained in the embodiment section. For example, in the Osaka area, the network follow control section 7 selects the first tuner 1 receiving NHK-FM Kobe 86.5 MHz using the switch section 4, and causes it to be played through the audio amplifier 100 and the speaker 101. When the second tuner 2 is in use, the reception frequency of the other second tuner 2 is changed, and when it receives a signal indicating a match in audio comparison from the audio comparison section 6, it is fixed at that reception frequency. In this case, the fixed reception frequency is NHK-FM Osaka 88.1MH.
It is z. The first tuner 1 is
If it is determined that the electric field strength of If it is reversed, the connection state of the switch section 4 is switched from the first tuner 1 to the second tuner 2. In this way, the network follow function automatically follows the location of a mobile object to a frequency where broadcasts with the same content but different frequencies depending on the region can be better heard.

[0006]

[Problems to be Solved by the Invention] However, although there are conventional radios that have a diversity function and a network follow function, there is no radio that has both functions. Therefore, there is a need to provide a radio that has both a diversity function and a network follow function. This request has the problem that if you simply combine Figures 5 and 6 to make a radio that has both functions, the number of tuners will be too large.If you simply combine the tuners, when using the network follow function,
When multipath occurs, the diversity function is activated and the tuner is switched, causing the problem that the network follow function no longer works.

Therefore, in view of the above problems, it is an object of the present invention to provide a diversity-equipped network follow radio that can effectively utilize a tuner.

[0008]

[Means for Solving the Problems] FIG. 1 is a diagram showing the basic configuration of the present invention. In order to solve the above problems, the present invention provides a diversity radio with an audio comparison section 6 and a switch section 8. The audio comparison unit 6 fixes the reception frequency of one of the first tuner 1 and the second tuner 2 used in the diversity-equipped radio, changes the frequency of the other, compares the audio content of both, and compares the audio content of both, and When the audio contents match, the switch unit 4 selects the tuner with the greater electric field strength.

The switch section 8 selectively selects the audio comparison section 6 and the diversity section 3 and causes the switch section 4 to switch.

0010

[Operation] In FIG. 1, according to the diversity-equipped network follow radio of the present invention, the reception frequency of one of the first tuner 1 and the second tuner 2 used in the diversity-equipped radio is fixed by the audio comparison section. Then, the frequency of the other one is changed, the audio content of both is compared, and the tuner with the larger electric field strength is selected by the switch 4 at the two different reception frequencies whose audio content matches. Section 6 is alternatively selected, and the network follow function is exhibited. At this time, the diversity function will stop. Conversely, when the diversity function is active, the network follow function stops. In other words, it is possible to perform both functions simply by using two tuners.

[0011]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a diagram illustrating a diversity-equipped network follow radio according to an embodiment of the present invention. The configuration of this figure will be explained. The diversity-equipped network follow radio shown in the figure includes a first tuner 1 and a second tuner 2. The first tuner 1 and the second tuner 2 include a high frequency amplifier circuit AF and a mixing circuit MIX, respectively.
, front end section F/E with local oscillation circuit VCO
11 and 21, an IF detection unit 12 and 22 that detects intermediate frequency signals of F/Es 11 and 21, low-pass filters LPFs 14 and 24 that control local oscillation circuits VCO of F/Es 11 and 21, and F/Es 11 and 21 local oscillation circuits VCO/LPF 14 and 24 constitute a phase-locked loop, and a crystal oscillator (not shown)
It includes its main parts PLLs 13 and 23 consisting of a phase comparator and a frequency divider.

The radio according to this embodiment further includes a diversity section 3 connected to the IF detection sections 12 and 22. The diversity section 3 extracts high frequency components contained in the output signals of the IF detection sections 12 and 22, detects multipaths, and averages them. It includes a level comparison section 32 that compares multipath levels.

Furthermore, the radio according to the present embodiment has a switch section that selects either one of the output signals of the IF detection section 12 or 22 having a smaller multipath level depending on the output signal of the level comparison section 32 of the diversity section 3. Contains 4. The radio according to this embodiment includes an audio comparison section 6, and the audio comparison section 6 includes a content comparison section 61 connected to the IF detection sections 12 and 22, and an S level related to the field strength of radio waves from the middle stage of the F/Es 11 and 21. Level comparison section 6 for inputting signals
2, and a gate circuit 63 that passes the output signal of the level comparison section 62 when the audio contents match in the content comparison section 61, and causes the switch 4 to be switched to the side with a larger electric field strength by this output signal.

Here, the content comparing section 61 takes the difference between the output signals of the IF detectors 12 and 23, rectifies and averages it, and when the average level becomes below a certain value, the IF detectors 12 and 23 output the difference.
It may be determined that the output signals of the two match. In addition, only the positive signals of the analog output signals of IF detection 12 and 23 are shaped into a rectangular wave with a constant amplitude, and then the difference in level between the two is taken. If the level difference becomes less than a certain value, it is considered that the contents of the two match. It may be something that does.

Furthermore, the radio according to this embodiment selectively selects the outputs of the level comparison section 32 of the diversity section 3 and the gate circuit 63 of the audio comparison section 6, and switches the switch section 4 with the selected signal. The switch section 8 includes a switch section 8 to FIG. 3 is a diagram showing the configuration of the radio control microprocessor. The radio according to this embodiment is PLL1
The radio control microprocessor 10 provides a frequency division ratio to 3 and 23 to select a broadcast station, and provides a signal to control switching of the switch section 8. The radio control microprocessor 10 connects an instruction section 31 that instructs the switch section 8 to select a diversity function and a network follow function from the outside or by a program, and a diversity control section 5 to the PLLs 13 and 23 when selecting the diversity function. When selecting the network follow function, a switch unit 32 connects the network follow control unit 7 to the PLLs 13 and 23.
includes.

Returning to FIG. 2, a noise blanker 104 that follows the switch unit 4 and removes pulse noise, and a stereo demodulator 103 connected to the noise blanker 104
, an audio amplifier 100 connected to a stereo demodulator 103, and a speaker 1 for reproducing the output of the audio amplifier 100. Next, a series of operations of this embodiment will be explained.

FIG. 4 is a flowchart illustrating a series of operations according to an embodiment of the present invention. As shown in this figure, the instruction section 31 of the radio control microprocessor 10
When the diversity control section 5 is selected (step 1), the switch section 8 is switched to the output side of the level comparison section 32 of the diversity section 3 (step 2). At the same time, the switch 32 of the radio control microprocessor 10 is switched to the diversity control unit 5 side, the same frequency division ratio T·B is sent to the PLLs 13 and 23, and the desired broadcast station is selected (step 3). The multipath levels of the multipath detection sections 31 and 33 in FIG. Switch to 1 (
Return to step 4 via step 5) and step 7. If L31≧L32 in step 4, the level comparison unit 32 connects the switch unit 4 to the second tuner 2 via the switch unit 8.
(Step 6). Steps 4 to 7 are thus repeated.

Next, when the network follow control section 7 is selected by the instruction section 31 of the radio control microprocessor 10, the switch section 8 is switched to the output side of the gate circuit 63 of the audio comparison section 6 (step 8).
). At the same time, the switch 32 of the radio control microprocessor 10 is switched to the network follow control section 7 side, and the frequency division ratio T is applied to the PLLs 13 and 23.
-B is sent (step 9). At this time, when the switch section 4 is on the first tuner 2 side and the network follow control section 7 is supplying the frequency division ratio T/B of the desired broadcast station to the PLL 13, the network follow control section 7
The frequency division ratio supplied to L23 is changed. Audio comparison section 6
The content comparison section 61 checks the consistency of the contents for each frequency division ratio that changes, and if they do not match, the gate circuit 63 is closed, and if they match, the gate circuit 63 is opened. At this time F
/Electric field strengths L61 and L62 from E11 and 21
are compared by the level comparison section 62, and the first tuner 1 compares the second
The electric field strength is L61>L62 than tuner 2 (
Step 10) If switch 4 is connected to first tuner 1
On the other hand, if L61≦L62, the level comparison section 62 switches the switch 4 to the second tuner 2 side via the gate circuit 63 and the switch section 8 (Step 12). Unless there is such an outage, either diversity control or network follow control is performed using the common tuner.

[0019]

[Effects of the Invention] As explained above, according to the present invention, two
Diversity control detects the multipath level in two tuners and switches the tuner, and network follow control detects the electric field strength of broadcasts with the same content but different reception frequencies and switches the tuner alternately. It is possible to exhibit diversity functions and network follow functions while suppressing an increase in the number of tuners.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle configuration of the present invention.

FIG. 2 is a diagram illustrating a diversity-equipped network follow radio according to an embodiment of the present invention.

FIG. 3 is a diagram showing the configuration of a radio control microprocessor.

FIG. 4 is a flowchart illustrating a series of operations according to the embodiment of the present invention.

FIG. 5 is a diagram showing a conventional diversity-equipped radio.

FIG. 6 is a diagram showing a conventional radio equipped with network follow.

[Explanation of symbols]

1...First tuner 2...Second tuner 3...Diversity Department 4, 8...Switch section 6...Audio comparison section 9...Control unit

Claims (1)

[Claims] [Claim 1] A first tuner (1) that performs tuning tuning.
, the second tuner (2), and the first tuner (2) that is tuned to the same station.
a diversity section (3) that detects and compares the multipath levels of the second tuner (1) and the second tuner (2);
and a switch unit (4) that selectively selects one of the two tuners (1, 2) with a lower multipath level, wherein the first tuner (1) and The reception frequency of one of the second tuners (2) is fixed and the frequency of the other is changed to compare the audio contents of both, and when the audio contents match, the tuner with the larger electric field strength is selected by the switch section. (4)
The voice comparison section (6) selected by the voice comparison section (6) and the voice comparison section (6)
and a switch section (8) that selectively selects the diversity section (3) to switch the switch section (4).
) and a diversity-equipped network follow radio.