JPS6298979A - Receiver - Google Patents

Abstract

PURPOSE:To change over and select a sound mode and to receive a satisfactory sound signal by setting a tuning frequency at a highly frequently using carrier position in the sound mode selected by a sound tuning means during changing over and selecting the sound mode received by a sound mode selecting means. CONSTITUTION:There are provided a receiving means 1 for receiving a broadcasting signal FM modulating a prescribed carrier by a signal obtained by multiplying an FM sound signal of the plural sound modes in which the carrier is situated in an upper side frequency band of a video signal and uses a carrier at an optional position on the video signal, the sound mode selecting means 2 for selecting the receiving sound mode among the plural sound modes, and the sound tuning means 3 for controlling a synchronizing frequency in order to receive the FM sound signal. When the receiving sound mode is changed over and selected by the sound mode selecting means 2, the tuning frequency is set at the carrier position high in using frequency in the selected sound mode by the sound tuning means 3. Thereby, in most cases, there is no trouble in the sound tuning and when the sound mode is changed over and selected, the sound signal can be received satisfactorily.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Field of industrial application B. Overview of the invention C. Prior art D. Problems to be solved by the invention E. Means for solving the problems (Fig. 1) F. Effect G. Examples (Figs. 2 to 16) ) G1 Explanation of reception channel selection G2 Explanation of audio system G3 Explanation of fine tuning G4 Explanation of reception inhibiting device A predetermined carrier wave is a multiplexed signal of FM audio signals of multiple audio modes using an arbitrary carrier wave and a carrier wave is located at FM.
The present invention relates to a receiver that receives a modulated broadcast signal.

B. Summary of the Invention The present invention provides a video signal with a carrier wave located in the upper frequency band of the video signal and a signal in which FM audio signals of a plurality of audio modes using arbitrary carrier waves are multiplexed.
In a receiver that receives M-modulated broadcast signals, when selecting the receiving audio mode, it is automatically tuned to the carrier wave position that is most frequently used in the selected audio mode. In this case, it is possible to select the switching of the audio mode and simultaneously receive the audio signal without having to worry about audio tuning.

C. Prior Art Conventionally, for example, as a format for satellite broadcasting signals, the first
As shown in FIG. 7, this video signal Sv is added to the video signal Sv.
A system is known in which an FM audio signal SAFM is multiplexed into the upper frequency band of the FM audio signal (see FIG. 3 of Japanese Patent Application No. 113462/1983). In this case, the carrier wave position of the FM audio signal SAFM is assumed to be constant. In the case shown, 5.5MHz
, 6.2MHz, 6.8MHz.

Therefore, in order to receive the FM audio signal S^mouth,
It is only necessary to match the tuning frequency to the carrier wave position which is considered to be constant, and for example, it is easy to perform good reception of audio signals immediately after turning on the power.

D Problems to be solved by the invention By the way, the 18th format of satellite broadcasting signals is
As shown in the figure, it is known to multiplex FM audio signals of multiple modes onto a video signal Sv, in which the carrier wave is located in the upper frequency band of the video signal Sv and uses a carrier wave at an arbitrary position. In this case, unlike the format shown in FIG. 17 above, the carrier wave position is arbitrary, so it is difficult to receive the audio signal immediately after selecting the mode change, and in many cases, the tuning operation is difficult. It becomes necessary.

The present invention has been made in view of the above problems, and it is an object of the present invention to make it possible to simultaneously select the switching of the audio mode and simultaneously receive the audio signal in a good manner without the trouble of audio tuning.

E Means for solving the problem (Fig. 1) The present invention has the following features:
As shown in FIG. 1, a signal (
Receiving means (11) for receiving a broadcast signal obtained by FM-shifting a predetermined carrier wave (see Fig. 18), and audio mode selection means (2) for selecting an audio mode to receive from among a plurality of audio modes.
and an audio tuning means (3) for controlling both frequencies in order to receive an FM audio signal.

Then, when the audio mode selection means (2) switches and selects the audio mode to be received, the audio nauning means (3) sets the tuned frequency to a frequently used carrier position in the selected audio mode. .

F Effect When selecting the audio mode switching, the tuning frequency is placed in a carrier wave position that is frequently used in the selected audio mode, so in many cases, the audio signal can be received satisfactorily at the same time as the audio mode switching is selected.

G. Embodiment Hereinafter, an embodiment of the present invention will be described with reference to FIG. In this example, 12GIIz band KU band, 4G
This is an example that is applicable to an ik star broadcasting receiver that receives the C band of the Hz band.

In the same figure, the ku band (1
2GHz band = 11.7~12.2GHz) or C band (4GIlz band = 3.7~4.2Gflz)
The satellite broadcast signal S8S is supplied to the S/II converter (12) via the BS antenna (11). This S/
In the U converter (I2), frequency conversion is performed and ku
Both the band and the C band are assumed to be signals SB6 of 950 to 1450 MHz.

That is, the local frequency for frequency conversion in the S/U converter (12) is 10.7 in the case of ku band.
Fixed at 5GIIz, 2.75GI for C band
It is fixed at Iz. Although only one system of BS antenna and S/U converter is shown in FIG. 2, in reality, the BS antenna and S/U converter are separate systems for receiving kLI band and C band. Taka switching is used.

As shown in FIG. 3, the satellite broadcasting signal SRS consists of a video signal Sv with a maximum frequency of 4.2 MHz and an FM audio signal SAFM in which a carrier wave is located in the upper frequency band of the video signal SV, for example, in the 5 to 8.5 MHz band. 12GH with multiplexed signal
The z-band or 4Gl (z-band carrier waves are each FM-modulated, so the signal Ss6 is also an FM signal.

Here, the audio modes of the satellite broadcasting signal SSS include: (1) monaural, (2) multiplex, (2) discrete, and (2) matrix. The FM audio signal SAFM in monaural mode is 5 to 8.5 in monaural audio signal sA.
A single carrier wave in the MHz band is FM-modulated, and its frequency deviation is, for example, 75 KHz. In addition, the FM audio signal SAFM in the multiplex mode is a composite signal of the sum signal (L + R) of the left audio signal R and the right audio signal R, and a signal obtained by FM modulating the subcarrier with the difference signal (L - R). A single carrier wave in the 5-8.5 MHz band is FM-modulated, and the frequency deviation thereof is, for example, 100 KHz.

In addition, the FM audio signal SA in the case of discrete mode
FM has a left audio signal and a right audio signal R of 5 to 3.
The first and second carrier waves in the 5 MHz band are FM modulated, and the frequency deviation thereof is, for example, 75 Kl(z).

In this case, the interval between the first and second carrier waves is, for example, 0.
It is often assumed to be 18Kl2. Furthermore, the FM audio signal SAFM in matrix mode is a sum signal (L+R
) and the difference signal (L-R), the first and second carrier waves in the 5 to 8.5 MHz band are FM-modulated, and the frequency deviation is, for example, I(lOXIfz. In this case,
The interval between the first and second carrier waves is, for example, 1.00 MHz.
It is often said that

Note that the position of the carrier wave of the FM audio signal 5AF14 in each mode described above is not uniformly determined, and is between 5.0 and 8.5.
The frequency is arbitrary in the MHz band, but the most frequent frequency is 6.80 MHz for monaural mode and multiplex mode, as shown in FIG. 4A-D.

5.58MHz for discrete mode, 5
．． 76MHz.

5.80MHz in matrix mode, 6.
It is 80MIIz.

Note that the number of channels in the KU band and C band is, for example, 24 channels. Broadcast signal SBS for each channel
The plane of polarization of is made different between adjacent channels. for example,
■、3. ..., 23 odd channels are horizontal, 2, 4
．． . . , 24 even channels are assumed to be vertical. This means that the required bandwidth per channel is, for example, 27MHz.
On the other hand, the frequency interval between each channel is approximately 20 MHz to protect against interference from adjacent channels.

In addition, in FIG. 2, the signal Sa6 from the S/IJ converter (12) is transmitted to the tuner (1) via the terminal (13).
00) is supplied to the signal processing circuit (14). In this signal processing circuit (14), the signal Ss6 of 950 to 1450 MFlz is converted into an intermediate frequency signal of 402.78 MHz, for example, and then FM demodulated to produce a video signal SV and FM audio as shown in FIG. 3 above. A composite signal So. with the signal SAFM is taken out.

In this case, the reception channel is selected each time the frequency of the local signal SL supplied from the PLL circuit (15) is changed for frequency conversion.

This PLL circuit (15) is controlled by the operation panel (16).
Based on the user's operation above, the microcomputer (
(17), hereinafter referred to as a "microcomputer", and is performed by controlling the frequency division ratio of the frequency divider of the PLL circuit (15) according to the channel. In addition, the processing circuit (
14) A signal 5ArN that does not change the intermediate frequency is supplied to the microcomputer (I7), and the intermediate frequency signal is correct.
AFT operation is performed to obtain 02.78Kl2.

Description of selection of G1 reception channel Here, the reception channel is randomly selected using the numeric keypad rlJ ~ "0" on the operation panel (16), and
Channels are selected sequentially using the up key (161) and down key (162).

First, random channel selection will be explained. The user presses the number corresponding to the desired channel using the numeric keys 1-1" to 1-0" on the operation panel (16), and finally presses the enter key r.
When you press ENTERJ, the microcomputer (17)
The frequency division ratio of the frequency divider of the LL circuit (15) is changed, and therefore the frequency of the local signal SL from the PLL circuit (15) is changed, and a desired channel is selected.

By the way, as described above, the plane of polarization of the broadcast signal SBS is determined to be horizontal or vertical, corresponding to each channel. Therefore, when changing the receiving channel, it is necessary to match the receiving polarization plane to that receiving channel.

The key (163) on the operation panel (16) is for switching the reception polarization plane. That is, it is output from the microcomputer (■7) to the terminal (19) via the amplifier (18), and S
The state of the switching signal SPO that controls the /U converter (12) to change the reception polarization plane is sequentially changed by operating this key (163), thereby switching the reception polarization plane.

Next, sequential channel selection will be explained. When the user presses the up key (161) or down key (162) on the operation panel (16), the PLL is activated by the microcomputer (17).
The frequency division ratio of the frequency divider of the circuit (15) is sequentially changed, and therefore the frequency of the local signal SL from the PLL circuit (15) is sequentially changed, and the receiving channels are sequentially switched and tuned. In this case, when the up key (161) is pressed, 1→3-...→23→2→4→...→24→1
→3→... When the reception channel is selected, and the down key (162) is pressed, 23→21
→・・・→l→24→22→・・・→2→23→21→
The channel is selected as follows. That is, odd-numbered channels and even-numbered channels are alternately selected.

In addition, as mentioned above, for example, the plane of polarization for odd channels is horizontal and the plane of polarization for even channels is vertical, so the reception plane of polarization is switched when moving from an even channel to an odd channel or from an odd channel to an even channel. . That is, at this time, the state of the switching signal SPO from the microcomputer (17) is changed and the reception polarization plane is switched.

The flowchart in FIG. 5 shows the operation during this sequential channel selection. That is, when the up key (161) is pressed (2), the number of channels CH is incremented by 2 (2). Next, it is determined whether the number of channels CH is 25 or more. When the number of channels is not 25 or more, the channel corresponding to the number of channels is selected. On the other hand, if the number is 25 or more, it is determined whether the number is even or odd. When the number of channels is odd, the number of channels CH is set to 2. When the number of channels is even, the number of channels CH is set to 1. Then, the receiving plane of polarization is inverted (2), and channels of the number of channels CH are selected (2).

The operation on the same side where the up key (161) is pressed is repeated, and the receiving channel when the button is stopped is finally selected.

Also, when the down key (162) is pressed, the number of channels CH is subtracted by 2 [phase]. Next, it is determined whether the number of channels CH is less than O or not.

If the number of channels is not less than O, the channel 'of that number of channels CH is selected. On the other hand, when it is less than θ, it is determined whether the number is even or odd. When the number is odd, the number of channels CH is set to 24 and 0, and when the number is even, the number of channels CH is set to 0.
H is assumed to be 23■. Then, the receiving plane of polarization is inverted (2), and channels of the number of channels CH are selected (2). The operation on the same side where the down key (162) is pressed is repeated, and the receiving channel when the down key (162) is stopped is finally selected.

In addition, when selecting this channel, the display section (201) of the display panel (20)
) displays the number of selected reception channels. In the example shown in the figure, it is shown that six channels are selected. Further, when the reception polarization plane is switched horizontally or vertically, the display section (202) or (203) of the display panel (20) is lit up. Here, the display section (204) of the display panel (20) is lit and displayed when broadcasting is received. In addition, the display section (205)
When receiving a band or a C band, for example, it is lit and displayed when receiving a C band.

In addition, the composite output S output from the signal processing circuit (14)
o (see Figure 3) is a de-emphasis circuit (21)
The signal that was pre-emphasized on the transmitter side is restored to its original state. The output of this de-emphasis circuit 173 (21) is supplied to a low-pass filter (22), and the video signal S
V is taken out, and this video signal Sv is amplified by an amplifier (23) and then supplied to an energy spread signal removal circuit (24). This removal circuit (24) removes the triangular wave energy diffusion signal superimposed on the video signal Sv on the transmission side, and the video signal SV from this removal circuit (24) is passed through the muting circuit (25). It is output to the output terminal (26). The muting circuit (25) includes a processing circuit (
14) is controlled by a control signal SMV formed from the presence or absence of a carrier wave with an intermediate frequency of 402.78 MHz, and is set in a muting state when there is no carrier wave with an intermediate frequency of 402.78 M1lz.

Explanation of G2 audio system Also, the synthesized output So output from the processing circuit (14) is supplied to the band pass filter (30) and has a frequency of 5.0 to 8.
．． FM audio signal SAFM whose carrier wave is located in the 5MHz band
is taken out. This FM audio signal 5AFN includes a mixer and constitutes a frequency converter PLLrI! The l paths (31) and (32) are supplied. These PLL1
Paths (3) and (32) are for converting the carrier wave of the FM audio signal SAFM to 10.7M1lz. In this case, as mentioned above, when the audio mode is monaural mode or multiplex mode, 5.0 to 3.
Since a single carrier wave in the 5 MHz band is used, a converted output can be obtained from, for example, a PLL circuit (31). On the other hand, in discrete mode or matrix mode, the first and second bands of 5.0 to 8.5
Since the carrier wave is used, conversion outputs can be obtained from both PLL circuits (31) and (32).

Here, as described above, the FM audio signal SAF of each mode is
The position of the carrier wave of M is not uniformly determined, and 5.
It is lazy in the 0-8.5MHz band. Therefore, the desired FM
In order to receive the audio signal SAFM, that is, to convert the carrier wave of the FM audio signal SAFM to an intermediate frequency of 10,7 Hz, the microcomputer (17) receives a signal from the microcomputer (17) based on the user's key operation on the operation panel (16). PLL circuit (31
) and (32) are supplied with frequency division ratio control signals S N 1 and SN2, respectively, and the frequency division ratios of the frequency dividers of the PLL circuits (31) and (32) are controlled to perform so-called tuning.

As mentioned above, the FM audio signal S of each mode
The position of the AFM carrier wave is arbitrary in the 5.0~8.5MHz band, but as shown in Figure 4A-D, in the case of monaural mode and multiplex mode, it is 6.80M) I
z, 5.58 MHz and 5.76 MHz in discrete mode, and 5.80 MIIz and 6.80 MHz in matrix mode.

The key (164) on the operation panel (16) is a key for selecting the audio mode, and by pressing this key (164') in sequence, the audio mode can be changed from monaural to multiplex → discrete → matrix → ox noral →... It is selected as follows. In this case, when switching to monaural mode and multiplex mode, the PLL circuit (31)
It is automatically tuned so that the tuning frequency f1 at is 6.80 MHz. Also, when switching to discrete mode, PLL circuits (31) and (32)
(7) Tuning frequencies 11 and f2 are automatically tuned to 5.58 MHz and 5.76 MHz, respectively. Furthermore, when switching to 7 trinox mode, the PL
Tuning frequencies f1 and f2 of L circuits (31) and (32)
are automatically tuned to be 5.80 MI (z and 6.80 MHz), respectively.

The flowchart in FIG. 6 shows the operation at the time of mode switching as described above. In other words, the voice mode selection key (1
When 64) is pressed, the current 7th card is determined. ■ If the mote is in mono mode, it can be switched to multiplex mode. And PLL[! li
Tuning frequency r1 in t path (31) is 6.80MHz
It is automatically tuned so that ■. Also, if the mode is multiplex mode, it can be switched to discrete mode■. Then, the PLL circuit (
31) and (32) are automatically tuned so that 1 and f2 are 5.58 MI (z and 5.76 MHz). Also, if the mode is discrete mode, switch to matrix mode. Then, the open frequency [1 and f2 in PLL circuits (31) and (32) are 5.80MlI2 and 6
．． Automatically tuned to 80MHz■. Furthermore, when the mode is matrix mode, it can be switched to monaural mode. And PLI,
The same il1 frequency f1 in circuit (31) is 6.80M
It is automatically tuned to become H2.

Furthermore, when switching to monaural mode, multiplex mode, discrete mode and matrix mode, the display panel (20) (7) display section (2)
06), (20?), (20B) and (209) are displayed with light emission.

In addition, as mentioned above, in the signal processing circuit (14),
When the reception channel is switched, the monaural mode is selected as the audio mode, and the tuning frequency f1 of the PLL circuit (31) is automatically tuned to 6.80M)Iz.

In this way, the same 1fi1 frequency is kept constant when switching between each mode, but if the carrier wave position of the FM audio signal 5AFN is not at the open frequency during this time, the user can tune by operating the keys on the operation panel (16). be made to do. Here, for tuning, press the voice tuning key (165) on the operation panel (16), then press the numeric keypad]
-1" to "0" or the up key (161) and down key (162). The case of discrete mode will be explained below as an example.

When the voice tuning key (165) is pressed, the display section (210) of the display panel (20) lights up, indicating that the voice tuning state is in progress, and the display section (210) lights up to indicate that the voice tuning state is in progress.
01), a display as shown in FIG. 7A is made. In the figure, "1-1" indicates the tuning frequency f1 in the PLI circuit (31), and r5.58J indicates the tuning frequency f1.
shows the value of Next, by keying in using the numeric keys "1" to "0" or pressing the up key (161') and down key (162), the tuning frequency f1 is set to the FM audio signal SAF of the first carrier wave in discrete mode.
M is sent to receive. Then, the newly set tuning frequency f1 is displayed on the display section (201>) of the display panel (20) as shown in FIG. 7B.

In this case, the Yasop key (161) and the down key (16
2) If the tuning is performed by each press, for example, in 10KHz steps.Then, based on the presence or absence of an intermediate frequency carrier, the sweep speed will be faster when there is no carrier, and the sweep speed will be slower when there is a carrier. be done.

By the way, as mentioned above, in the case of discrete mote, the interval between the first and second general transmission waves is statistically 0.18M.
) Iz. Therefore, this tuning frequency f1
When tuning, the tuning frequency r2 in the PLL circuit (32) is automatically set to f1+0.18M1lz. That is, as shown in FIG. 7B, fl is 5.3.
If it is 0MHz, f2=5.30+0.18=5
．． It is assumed to be 48MHz. When the FM signal S8 of the second carrier in the discrete mode is received at this tuning frequency f2, the tuning is completed.

On the other hand, when the FM audio signal 5AF14 of the second carrier wave of the discrete mote cannot be received at this tuning frequency 12, the audio tuning key (1
65). At this time, a display similar to that shown in FIG. 7C is displayed on the display section (201) of the display panel (20). In the figure, "2" indicates the tuning frequency r2 in the PLL circuit (32), and r5.48J indicates the value. Next, by keying in using the numeric keys "1" to "0" or pressing the up key (161) or down key (162), the tuning frequency f2 will receive the FM audio signal SAFM of the second carrier wave in discrete mode. Set. In this case as well, the up key (161),
When tuning is performed by pressing the down key (162), for example, it is performed in 10 Kllz steps,
Further, when there is no intermediate frequency carrier wave, the sweep speed is increased, and when there is a carrier wave, the sweep speed is decreased. Note that this tuning of the intermittent frequency f2 is performed independently.

The above has been explained using the case of discrete mode as an example, but the case of matrix mode is almost the same. In this case, when tuning frequency f1, tuning frequency f2 is automatically set to f 2 + 1.00MHz. Ru.

Further, in the case of monaural mode and multiplex mode, it is sufficient to tune only the tuning frequency f1.

The flowchart in FIG. 8 shows the operation during the above tuning. That is, when the voice tuning key (165) is pressed (2), the tuning state of frequency f1 or f2 is set (2). That is, each time the key (165) is pressed, the tuning state is set to f□ or f2. When a predetermined frequency is keyed in using the numeric keypad rlJ~"0", it is determined (2) whether or not the frequency f1 is in the tuning state.

When in the tuning state of frequency f1, the PLL circuit (
The tuning frequency f1 in 31) is set to the keyed-in frequency. Next, it is determined whether the mode is discrete mode or matrix mode. When in monaural or celltibrex mode, which is not one of these modes, it returns to the key sense state, while in these modes, it is determined whether or not it is in discrete mode.

In discrete mode, frequency f2 is rt+0
．． 18KIIz■, and when in matrix mode rather than discrete mode, frequency f2 is f1+1
．． 00MHz■. Next, the frequency f2 is 8.5M
[Phase] to be determined whether it is greater than Hz. 8.5M1l
If it is not larger than Z, leave it as is, 8,5 MHz
When it is larger, f2-8.5MIIZ is set to 0, and the tuning frequency f2 in the PLL circuit (32) is set@. Then, the state is returned to the key sense state.

On the other hand, instead of the tuning state of frequency f+, frequency f
2, the PLL circuit (32
) The tuning frequency r2 at 0° is centered at the keyed-in frequency, and the state is returned to the key sense state.

Also, when the up key (161) is pressed, ■, frequency f
[Phase] in which it is determined whether the tuning state is 1 or not.

When the frequency f1 is in the tuning state, the frequency f1 is set to f1+10 Hz [phase]. Next, it is determined whether the frequency "1 is greater than 8,5Ml1z@,8
．． If there are no people below 5MHz, leave it as is, 8.5M
When I(z is greater than r 1 =5.0M1(Z
Then, the tuning frequency f1 in the PLL circuit (31) is set to [phase]. Thereafter, the operations ① to 0 described above are performed.

On the other hand, it is not the tuning state of frequency f1, but the frequency f
2, the frequency f2 is f
2 + 10 KIIz [phase]. Next, the frequency [2
[Phase] is determined whether or not is greater than 8.5 MHz.

If it is not larger than 8.5Ml1z, leave it as is, 8
, 5 Mllz, then f 2 = 5.
0 MHz, and the tuning frequency f2 in the P L Ll path (32) is set. The operation on the same side in which the 0° up key (161) is pressed is repeated.

Also, when the down key (162) is pressed, ■, frequency f
[Phase] in which it is determined whether or not x is in the tuning state.

In the tuning state of frequency 11, the frequency f1 is set to f 1 10KH2. Next, the frequency f1 is 5
．． [Phase] to be determined whether it is smaller than 0 MHz. 5.
If it is not smaller than 0MHz, it remains as is, and if it is smaller, it is set to f1=8.5MHz, and P L I-
The tuning frequency f1 in the circuit (31) is set.■
. Hereinafter, J: The operations of ■ to @ described above are performed. On the other hand, when the tuning state is not the frequency f1 but the frequency f2, the frequency f2 is f210KH.
■It is said to be z. Next, it is determined whether the frequency f2 is smaller than 5.0 MHz [phase]. If it is not smaller than 5.0KHz, leave it as is; if it is, r2=8.
5MIIz is set [phase], and the opening frequency f2 in the PLL circuit (32) is set.

In FIG. 2, an audio signal SA1 with a carrier wave of 10.7 MHz obtained from a PLL circuit (31) is passed through a narrowband bandpass filter (33) and a wideband bandpass filter (33).
4) are supplied to the A-side and B-side fixed terminals of the changeover switch (35), respectively. Further, the audio signal SA2 with a carrier wave of 10.7 MHz obtained from the PLL circuit (32) is passed through a narrowband bandpass filter (36) and a wideband bandpass filter (37) to a changeover switch (38).
・When the audio mode is monaural mode or discrete mode, the frequency deviation is relatively narrow at 75 KHz, so
The changeover switches (35) and (38) are switched to the A side, and the audio signals SA1 and SA2 that have passed through the narrowband bandpass filters (33) and (36) are obtained from the changeover switches (35) and (38). It will be done. On the other hand, when the audio mode is multiplex mode or matrix mode, as mentioned above, the frequency deviation is relatively wide at 100 KHz, so the changeover switches (35) and (38) are connected to the broadband bandpass filters (34) and (37). ) are obtained as audio signals SA□ and SA2.

Switching of the changeover switches (35) and (38) is performed as follows. That is, the microcomputer (17) outputs a 2-bit signal (A) in response to the selection of the audio mode.

B] is generated. That is, [1, 1) in monaural mode and [0, 1) in multiplex mode.
0), (1,0] in the discrete mode, and (0,1) in the matrix mode.

The flowchart in FIG. 9 is based on these 2-bit signals (A,
This shows the operation of B). That is, when the voice mode selection key (i64) is pressed, the current mode is determined. If the mode is monaural mode, it is switched to multiplex mode (2) and a 2-bit signal (0, O) is generated. If the mode is multiplex mode, it is switched to discrete mode (2) and a 2-bit signal (1, O) is generated.

If the mode is discrete mode, it is switched to matrix mode and a 2-bit signal (0, 1) is sent.
■ will occur. If the mode is matrix mode, it is switched to monaural mode (2) and a 2-bit signal (1, 1) is generated.

In this way, signal A is 1" in monaural mode and discrete mode, and "0" in multiplex mode and matrix mode, and the selector switch (35)
This signal A is supplied to (38) as a switching signal. Then, when the signal A is "1", "0" is sent to the A side.
”, it is switched to the B side.

Audio signals SA1 and SA2 taken out from the changeover switches (35) and (38) are supplied to FM demodulators (39) and (40), respectively. And these FMlj regulators (
The demodulated outputs from (39) and (40) are sent to the audio processing circuit (4
1).

The audio processing circuit (41) performs processing according to each audio mode. That is, the 2-bit signals (A, B) from the microcomputer (17) are supplied to the decoder (42), and the decoder (42) converts them into 4-bit signals (A, B).

b, c, d) and then sent to the audio processing circuit (41
) as a 1+lI fall signal. For example, (1, 1) in monaural mode is (1, 0, 0,
0), (0,0) in multiplex mode becomes (0,1,0,01), [1,0) in discrete mode becomes (0,0,1,0), matrix remote mode In this case, [0, i) is converted to (0,0°0.1]. This controls the audio processing circuit (41) and performs processing according to each audio mote.

In the case of monaural mode, monaural audio signals are extracted from the first and second outputs of the processing circuit (41),
Output terminals (47) and (43) and (44) and muting circuits (45) and (46) respectively.
48). Also, multiplex mode,
In the case of discrete mode and matrix mode, the left audio signal R and the right audio signal R are taken out from the first and second outputs of the processing circuit (41), respectively, and are sent to the amplifier (43), respectively.
) and (44), muting circuit (45) and (4
6) to output terminals (47) and (48).

Also, when there are audio signals SA1 and SA2 from the FM recovery circuits (39) and (40), respectively, the low level "0" is output.
, signals SM1 and 5 which become high level “l” when there is no
142 are output and supplied to the AND circuit (49), respectively. When the output of the antenna circuit (49) is at a high level "1", that is, when there is no audio signal SΔ1 or SA2, the muting circuits (45) and (46) are operated.

Also, signals 5 from the FM demodulation circuits (39) and (40)
141 and 3M2 are supplied to the microcomputer (17), and as mentioned above, the up key (161) or the down key (
162) is used for sweep speed control during audio signal tuning.

Description of G3 Fine Tuning Also, the key (166) on the operation panel (16) is a key for fine tuning. That is, it is used to prevent beat disturbance due to interference between broadcast signals (SHF waves) from broadcasting satellites and terrestrial communication signals (SHF waves), and is used to select reception channels in the signal processing circuit (14). The center frequency of tuning is slightly shifted.

When the fine tuning key (16B) is pressed, the display section (201) of the display panel (20) shows the first O.
A display is made as shown in Figure A. In the figure, rO,
oOJ indicates that the center frequency of tuning is not shifted. Next, when the up key (161) or the down key (162) is pressed, the center frequency of tuning is shifted by, for example, 0.2 MHz steps. In this case, the shifted frequency is displayed on the display section (201) as shown in FIG. 10B. The amount of shift is set to such an extent that the interference becomes less noticeable than, for example, the screen, and is set to a maximum of approximately ±IOMIIZ. This is because if you shift it too much, the screen will become distorted. Also, at this time, AFT! II production will be prohibited and the shifted frequency will be prevented from returning to its original state. When the receiving channel is switched, this prohibition of AFT operation is canceled. Note that the AFT operation is started when the power is turned on. In FIG. 11, r+ is the interference frequency, f,
When is the original tuning center frequency, the center frequency is forcibly shifted, for example fF.

The flowchart in FIG. 12 shows the operation related to the above fine tuning. That is, the AFT operation is started when the power is turned on. When the fine tuning key (166) is pressed (2), the tuning center frequency can be shifted (2). When the up key (IBI) is pressed, ■・Shift Δf increases to +IO
It will be determined whether it is MIIz or not■. When it is not +10 MIIz, Nayuhaning's center frequency fo is (o + 0
．． When the frequency is set to 2HIlz (2), and +lOMHz, the tuning center frequency fo remains unchanged (2), and the AFT operation is prohibited (3), returning to the key sense state.

The operations for the songs in which the amp key (161) is pressed are repeated. On the other hand, when the down key (162) is pressed, it is determined whether the shift amount Δf is -10M1lz or not.
phase], when it is not 10MIIz, the tuning center frequency fo is foO,2Ml1z, and σp,
When it is 1OMHz, the tuning is performed with the tuning center frequency fo unchanged■. And A.F.
The T operation is prohibited and the state is returned to the key sense state.

The operations for the songs for which the down key (162) is pressed are repeated.

Further, when there is a key-in using the numeric keypad "1" to "1'0", the inhibition of the AFT operation is canceled and the channel is tuned to G3, and then the reception channel corresponding to the number keyed-in is selected.

G4 received! 4. Description of the Main Device Furthermore, in the example shown in FIG. 2, reception of a predetermined selected channel can be prohibited. That is, a state in which a predetermined channel is selected (the 113th IA is displayed on the display section (201
) on the operation panel (16) (parent key) (167) is pressed, the display section (20) shows the first
3 A display is made as shown in FIG. Next, when a three-digit index signal ID is input using the ten keys "1" to "0", a display as shown in FIG. 13C is displayed on the display section (201). Next, when the enter key rENTERJ is pressed, if the manually entered index signal ID matches the index signal IDo corresponding to a predetermined channel stored in advance in the nonvolatile memory (50), the display unit (201) A display as shown in Figure 13 is made, and reception of this predetermined channel, 6 channels in the illustrated example, is prohibited. On the other hand, index signal ID
If it does not match IDo, the original display is displayed on the display section (201) as shown in FIG. 13, and reception of the predetermined channel is not prohibited.

In this case, the PLL circuit (15
) is changed to change the frequency of the local signal SL, and the center frequency of tuning becomes 950 to 1450.
For example, the frequency is set to 1480 MHz outside the MHz band. Therefore, when the reception is prohibited, there is no carrier wave of 402, 78 MHz in the signal processing circuit (14), and the muting circuit (25) operates to enter the video muting state.

Also, at this time, since the signals SM1 and SN2 from the FMfU tone circuits (39) and (40) both become high level "1", the muting circuits (45) and (46) operate to enter the audio muting state. Become.

In addition, a state in which a predetermined channel is selected and reception of this channel is prohibited (see the display section in Fig. 14A) is also possible.
(201) shown), press the key (16) of the operation panel (16).
7) is pressed, the display section (201) will display the screen shown in Fig. 14B.
The display will be as shown below. Next, numeric keypad rlJ~
When a 3-digit index signal ID of "0" is input, a display as shown in FIG. 14C is displayed on the display section (201). Next, when the enter key rENTERJ is pressed, the input index signal ID will be transferred to the non-volatile memory IJ.
(50), if it matches the index signal IDo corresponding to the predetermined channel stored in advance, a display as shown in Figure 14 is made, and the reception prohibition state of the predetermined channel, channel 6 in the illustrated example, is released. be done.

On the other hand, if the index signal ■D does not match IDo, the original display is displayed on the display section (201) as shown in FIG. 14E, and the reception prohibited state of the predetermined channel is not released.

In this case, when the reception prohibition state is canceled, the tuning center frequency is returned to the correct position, and the muting circuits (25), (45), and (46) also stop operating and enter the muting state. is canceled.

Further, when changing the index signal IDo corresponding to a predetermined channel stored in the nonvolatile memory (50), the following procedure is performed. That is, when the key (167) on the operation panel (16) is pressed while a predetermined channel is selected (1 button on the display (201) in FIG. 15A), a message appears on the display (201). is displayed as shown in FIG. 15B. Next, when a three-digit index signal IDI is input using the ten keys 11" to "0", a display as shown in FIG. 15C is displayed on the display section (201). Next, when the 3-digit index signal TD2 is input, the display section (201
) is displayed as shown in Figure 15. next,
When the enter key r ENTERJ is pressed, if the manually input index signal TDI matches the index signal IDo corresponding to a predetermined channel stored in advance in the non-volatile memory (50), the index signal J is pressed.
D2 is stored in memory as index signal IDo (50)
At this time, the display section (201) shows the image shown in FIG.
As shown in the figure, the index signal ID2, rl in the example shown in the figure
11J is displayed.

On the other hand, if the index signal D1 and TDo do not match, a display as shown in FIG. 15F is displayed on the display section (201), and the index signal IDo stored in the memory (50) is left unchanged.

The memory (50) stores an index signal rDo common to each cent corresponding to each channel at the time of shipment from the factory.

In addition, if you forget the index signal IDo stored in the memory (50), you can use the factory code, that is, the index signal like a master key, such as r999.
J is prepared and used in the worst case.

The flowchart in FIG. 16 shows the above operation. That is, in a predetermined receiving channel selection state,
When the key (167) on the operation panel (16) is pressed,
rPJ is displayed on the display unit (201), and the reception is prohibited, the prohibition is canceled, or the index signal IDo is registered. Next, an index signal is input manually using the numeric keys "1" to "0" (■), and when the enter key rENTERJ is pressed (■), it is determined whether there are three digits or not (■). In the case of 3 digits, one index signal rD was input using the numeric keypad "1" to "0", so next, this manual index signal ID is input to the non-volatile memo IJ (50)
It is determined whether the index signal IDo matches the index signal IDo stored in advance. If they do not match, the display on the display section (201) is returned to the original state (■) and the key sense state is established. If they match, it is determined whether or not reception is prohibited. If the reception is not prohibited, it is determined that the operation is not intended to prohibit reception, and the reception is prohibited.■
. Then, the center frequency of tuning is set to be outside the band [phase], rPLJ is displayed on the display (201),
It is said to be in a state of key sense. In addition, if reception is prohibited, it is determined that the operation is to cancel the reception, and the reception prohibition is canceled (0°), and the center frequency of tuning is returned to its original position so that the predetermined channel can be received. $, rPLJ on the display section (201) is erased, and ■, the key sense state is returned.

Also, if it is not 3 digits, it is then determined whether it is 6 digits or not, and if it is not 6 digits, the original display is returned [phase], and the key sense It is said to be in a state of 6
In the case of digits, the index signals IDI and ID2 were input manually using the numeric keys 1-1'' to 0'', so the manual index signal IDI was then stored in advance in the non-volatile memory (50). index signal ID
It is determined whether it matches o. Oo If it does not match, it is determined whether it is a factory code or not σ)
. If it is not a factory code, "===" is displayed and the key sense state is set to qφ. on the other hand,
If the index signals IDI and IDo match, or if the index signal IDI is a factory code, the input index signal ID2 is stored in the memory (50) as the index signal IDo.
). Then, this index signal ID2 is displayed on the display section (2
01) is displayed, and the key sense state is displayed.

Note that the key (168) on the operation panel (16) is a key for using the signals output to the output terminals (26), (47), and (4B) as external input signals. In order to simplify the drawing, external input terminals, switching switches, etc. are not shown in FIG. 2. Further, for example, when switching to the external input side, the display section (211) of the display panel (20) is lit up.

In this way, according to this example, the received audio mode can be changed from monaural to monaural by using the h key (164) on the operation panel (16).
When switching from multiplex to discrete to matrix to monaural, the system automatically tunes to the frequently used carrier wave position in the selected audio mode.1. In many cases, it is possible to successfully receive an audio signal at the same time as switching the audio mode without the trouble of audio tuning.

In addition, when a predetermined channel is selected, inhibiting or canceling the reception of the predetermined channel has the same index as the index signal IDo stored in advance in the non-volatile memo IJ (50) corresponding to the predetermined channel. (No. 4 can only be done manually. Furthermore, a new index signal ID.

It is virtually impossible to register (which can be done with factory code).

Therefore, if you do not know the index signal IDo, it is difficult to remove the reception prohibition state. For example, it is possible to reliably prevent a child from canceling the prohibition state without permission, and it is difficult to fully utilize the reception prohibition function. can.

Furthermore, when reception is prohibited, video and audio are automatically muted, so when selecting a channel whose reception is prohibited, it is possible to avoid viewing a disturbed screen and noise.

In addition, during audio tuning in discrete mode and matrix mode, the PLL circuit (31
) Tuning frequency f1 and P L, L circuit (32)
Since the tuning frequency f2 in is tuned with f2 ft constant (the frequency interval with the largest number of first and second carrier waves), the troublesomeness of tuning these modes is reduced.

Furthermore, since it has a fine tuning function, it can effectively prevent or reduce interference with terrestrial communication waves.

Furthermore, when sequentially selecting reception channels, odd channels and even channels with different planes of polarization are alternately selected, so the switching speed of reception channels can be increased because there is less switching of reception polarization planes. Furthermore, since the reception polarization plane is automatically switched, there is no need for the user to switch the reception polarization plane.

In addition, since the intermediate frequency filters (33) to (37) are automatically switched according to the frequency deviation of each audio mode, noise or sound distortion caused by incorrect selection of the bandwidth of the intermediate frequency filter can be suppressed. can be prevented.

Note that, for example, prohibition of reception based on an index signal is not limited to the above-described embodiment, and can be similarly applied to other receivers. In addition, in the above embodiment, the polarization plane of odd-numbered channels is horizontal and the polarization plane of even-numbered channels is vertical, but the same applies to the reverse case, or to the case of right-handed circularly polarized waves and left-handed circularly polarized waves. be. Further, although the reception is prohibited outside the band (outside the 950 to 1450 MHz band), it is sufficient to set the receiving rate between stations +=J even within the band.

I4 Effects of the Invention According to the present invention described above, when selecting the receiving audio mode, the system automatically tunes to the frequently used carrier wave position in the selected audio mode.
In many cases, it is possible to successfully receive an audio signal at the same time as switching the audio mode without the trouble of audio tuning.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of the present invention, FIG. 2 is a configuration diagram showing an embodiment of the present invention, and FIGS. 3 to 16 are diagrams for explaining the same.
FIG. 17 and FIG. 18 are diagrams for explaining the conventional technology. (16) is an operation panel, (17) is a microcomputer, (50) is a nonvolatile memory, (100) is a tuner, and (164) is a key for selecting an audio mode.

Claims (1)

[Claims] Broadcasting in which a predetermined carrier wave is FM-modulated with a signal obtained by multiplexing a video signal with FM audio signals of a plurality of audio modes in which the carrier wave is located in the upper frequency band of the video signal and the carrier wave is at an arbitrary position. The above-mentioned device has a receiving means for receiving a signal, an audio mode selecting means for selecting an audio mode to receive from among the plurality of audio modes, and an audio tuning means for controlling a tuning frequency for receiving the FM audio signal, A receiver characterized in that when the audio mode selection means switches and selects the audio mode to be received, the audio tuning means sets a tuning frequency to a carrier wave position that is frequently used in the selected audio mode.