JP2003152580A - High-frequency signal receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of the distortion of a high-frequency signal receiver for receiving a specific segment being large. SOLUTION: This device is provided with an input terminal 31 to which a digital broadcasting wave is inputted, a mixer 35 to whose one input a signal inputted to the input terminal 31 is supplied, and to whose other input the output signal of a local oscillator 34 is supplied, a band-pass filter 36 to which an intermediate frequency to be outputted from the mixer 35 is supplied, and an output terminal to which the output of the band pass filter 36 is supplied. The band width of the band-pass filter 36 is set, so as to be made narrower than the overall width of a plurality of segments included in the one channel. Also, this device is provided with an intermediate frequency control means for controlling the oscillation frequency of the local oscillator 34, so that the frequency of a segment to be received in one channel can be set so as be turned into the intermediate frequency to be outputted from the mixer 35. Thus, distortion can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel.

[0002]

2. Description of the Related Art As shown in FIG. 9, a conventional high frequency signal receiving apparatus connects an input terminal 1 to which a digital broadcast wave including a plurality of segments in one channel is input, and a signal input to the input terminal 1. A high frequency amplifier 2 and a mixer 5 in which the output of the high frequency amplifier 2 is supplied to one input and the output signal of a local oscillator 4 loop-connected to the PLL circuit 3 is connected to the other input; A filter 6 for passing the first intermediate frequency output from the mixer 5, and an output of the filter 6 is supplied to one input and a local oscillator 8 loop-connected to a PLL circuit 7 at the other input. A mixer 9 to which the output of the mixer 9 is supplied, an output terminal 10 to which the second intermediate frequency output from the mixer 9 is supplied, a data terminal 11 for providing tuning data to the PLL circuit 3, Respectively reference frequency was composed of quartz oscillator 12 supplies the LL circuit 3 and 7.

The operation of the high frequency signal receiving apparatus configured as described above will be described below. As shown in FIG.
A 70 MHz digital broadcast wave is input. The digital broadcast wave 15 is mixed with the output of the local oscillator 4 by the mixer 5 and converted into an intermediate frequency 16 of 1205 MHz as shown in FIG. That is, it is a translation that is selected.

The intermediate frequency 16 output from the mixer 5 is mixed with the output of the local oscillator 8 in the next mixer 9 through the filter 6 and fixed at 4 MHz as shown in FIG. 10 (c). Is converted into the intermediate frequency 17 that has been generated. The horizontal axis 18 in FIG. 10 is frequency (MHz).
Is.

Here, among the digital broadcast waves 15, CH7 having a center frequency of 190 MHz is a digital broadcast wave including eight segments in one channel 19 as shown in FIG. 11, and each segment is different. Includes voice and music broadcasts. In this case the bandwidth is 20
Is 4 MHz. Further, in the channel 21 including the video wave transmitted using 470 to 770 MHz,
As shown in FIG. 12, the bandwidth 22 is 6 MHz, and one channel in this band includes 13 segments. The one segment at the center is voice or music broadcasting. In this way, the bandwidth of the filter 6 that passes the intermediate frequency is 6 MHz so that both digital broadcast waves 15 can be received.

Further, in order to prevent interference with the existing analog broadcast wave, the transmission power of the digital broadcast wave using the empty CH is lowered and transmitted, and the analog broadcast is received when the digital broadcast wave is received. Waves will be present adjacent to each other and will be disturbed, resulting in BER deterioration and incorrect reception.

[0007]

In such a conventional structure, the bandwidth of the filter 6 is appropriate for processing all of digital television broadcasting and digital audio broadcasting. However, in this, for example, only voice 1
There is also a demand for a receiving device that wants to receive only segments.

In such a receiving device which receives only one segment, the band of the intermediate frequency filter 6 is set to 6
If the frequency is set to MHz, there is a problem that an excessive signal is input to the mixer 9 more than necessary and distortion occurs.

Further, in order not to interfere with the existing analog broadcast wave, the transmission power of the digital broadcast wave using the empty CH is lowered and transmitted, and the analog broadcast is received when the digital broadcast wave is received. Waves will be present next to each other and will be disturbed. Further, when digital broadcasting becomes widespread, even when a strong digital broadcasting wave is near and a weak digital broadcasting wave is received far away, interference by, for example, an adjacent CH occurs. As a result, there is a problem that BER deteriorates and correct reception cannot be performed.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a high frequency signal receiving apparatus with less distortion.

[0011]

In order to achieve this object, a high frequency signal receiving apparatus of the present invention is a high frequency signal receiving apparatus for receiving a digital broadcast wave containing a plurality of segments in one channel, wherein the high frequency signal is received. The receiving device has an input terminal to which the digital broadcast wave is input, and an output signal of a local oscillator which is supplied to one input with the signal input to the input terminal and is loop-connected to the other input with a PLL circuit. And a bandpass filter to which the intermediate frequency output from the mixer is supplied,
An output terminal to which the output of the bandpass filter is supplied, and the bandwidth of the bandpass filter is 1
The width of the plurality of segments included in a channel is made narrower than that of the plurality of segments, and the frequency of the desired segment included in the one channel is set to the predetermined intermediate frequency output from the mixer. An intermediate frequency control means for controlling the oscillation frequency is provided. This can reduce distortion.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a high-frequency signal receiving apparatus for receiving a digital broadcast wave containing a plurality of segments in one channel, wherein the high-frequency signal receiving apparatus is the digital signal. An input terminal to which a broadcast wave is input, and a mixer to which the signal input to this input terminal is supplied to one input and the output signal of a local oscillator loop-connected to the PLL circuit is supplied to the other input. And a bandpass filter to which the intermediate frequency output from the mixer is supplied, and an output terminal to which the output of the bandpass filter is supplied. The bandpass filter has a bandwidth of 1 channel. The frequency of the desired segment included in the one channel is output from the mixer while being narrower than the entire width of the plurality of included segments. Intermediate frequency control means for controlling the oscillation frequency of the local oscillator such that the intermediate frequency defined because a high-frequency signal receiving apparatus provided with,
Since the band width of the band pass filter is narrower than the total width of the plurality of segments, the signal energy transmitted to the subsequent stages is small. Therefore, distortion can be reduced. Further, the power of the signal to the next stage and thereafter is reduced, so that power saving can be achieved accordingly. Therefore, the battery life can be extended when used in a portable device or the like.

Further, since the band width of the bandpass filter is narrowed, the interference received from the adjacent channel is reduced.

The bandpass filter according to the second aspect of the present invention is the high-frequency signal receiving apparatus according to the first aspect, which is formed of a SAW filter. Since the SAW filter is used, miniaturization can be realized and adjacent A large amount of signal attenuation can be taken.

The invention according to claim 3 is the high-frequency signal receiving device according to claim 1 in which the bandpass filter has a bandwidth of approximately one segment, and the signal energy to the next stage and thereafter is the smallest. Therefore, distortion can be reduced.

The invention according to claim 4 is the high-frequency signal receiving device according to claim 1 in which the bandpass filter has a bandwidth of approximately 3 segments. Even if there are variations in the passband frequency), it is possible to reliably pass the signal with a margin, and you can listen to the desired broadcast without problems. Further, even if the environment such as the ambient temperature changes and the characteristics and performance of the parts change, for the same reason, it is possible to reliably listen to the desired broadcast with a margin.

The fifth aspect of the present invention is the high-frequency signal receiving apparatus according to the fourth aspect, wherein a trap filter for removing an interfering frequency is inserted in series with the bandpass filter, and the variation of the bandpass filter is trapped. Since it is possible to correct the distortion, it is possible to reduce the transmission of signal energy to the subsequent stages and reduce the distortion, and it is possible to listen to the desired broadcast reliably with a margin.

The trap filter of the invention described in claim 6 is the high-frequency signal receiving device according to claim 5 in which the trap frequency can be adjusted, and even if the pass band of the band pass filter varies. Since the variation can be adjusted by the trap filter, it is possible to minimize the signal energy to the subsequent stages and reduce the distortion. Also, since the necessary signals can be passed through with certainty, the desired broadcast can be heard without any problems.

The trap filter of the invention described in claim 7 is formed by a series connection circuit of an inductor and a capacitor formed by a pattern, and the inductance value of the inductor is adjusted by laser trimming. In the high-frequency signal receiving device, since the inductor is formed in the pattern, it can be thinned and the inductance value does not change even with vibration. In addition, since the inductance value is adjusted by laser trimming, it is possible to minimize the signal energy to the next and subsequent stages and reduce distortion, and it is possible to pass the necessary signal with a margin. Can be heard without problems.

The trap filter of the invention described in claim 8 is formed by a series connection circuit of an inductor and a capacitor formed by a pattern, and the capacitor uses a varicap diode, and a capacitance is formed by applying a voltage from the outside. The high-frequency signal receiving apparatus according to claim 6, wherein the value is adjusted, and the capacitance value of the capacitor is adjusted by the voltage, so that adjustment from the outside is possible even after assembly.

According to a ninth aspect of the present invention, at least the mixer, the local oscillator, and the PLL circuit are integrated in the same package, and the high-frequency signal receiving device according to the first aspect is integrated. Therefore, it is possible to reduce the size and manage parts and reduce the number of manufacturing steps.

According to a tenth aspect of the invention, the PLL circuit is the high-frequency signal receiving apparatus according to the first aspect, in which the PLL circuit is controlled by a microcomputer, and the oscillation frequency can be easily controlled.

The invention according to claim 11 is a high-frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high-frequency signal receiving apparatus is an input to which the digital broadcast wave is input. A terminal and a signal input to the input terminal is supplied to one input and an output signal of a first local oscillator loop-connected to the first PLL circuit is supplied to the other input. A mixer, a filter supplied with the first intermediate frequency output from the first mixer, an output of the filter supplied to one input and a second P output supplied to the other input.
A second mixer to which the output of the second local oscillator loop-connected to the LL circuit is supplied; and an output terminal to which the second intermediate frequency output from the second mixer is supplied, The first intermediate frequency is set to be higher than the frequency of the digital broadcast wave, the second intermediate frequency is set to be lower than the frequency of the digital broadcast wave, and the bandwidth of the band-pass filter is the channel 1 The width of the plurality of segments included therein is narrower than that of the plurality of segments, and the frequency of the desired segment included in the one channel is set to the predetermined first intermediate frequency output from the first mixer. A high-frequency signal receiving device having an intermediate frequency control means for controlling the oscillation frequency of the first local oscillator, wherein the band pass filter has a plurality of bandwidths. Since the narrower than the overall width of the instrument, the signal energy transmitted to the next stage and subsequent stages is reduced. Therefore, distortion can be reduced. Further, the power of the signal to the next stage and thereafter is reduced, so that power saving can be achieved accordingly. Therefore, the battery life can be extended when used in a portable device or the like.

Further, since the band width of the band pass filter is narrowed, the interference received from the adjacent channel is reduced.

Furthermore, since the first intermediate frequency is set to be higher than the frequency of the digital broadcast wave, it is possible to easily obtain a high frequency signal receiving device that does not suffer from image frequency interference in the reception broadcast band.

According to a twelfth aspect of the present invention, there is provided a high frequency signal receiving device for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high frequency signal receiving device is an input to which the digital broadcast wave is input. A terminal and a signal input to the input terminal is supplied to one input and an output signal of a first local oscillator loop-connected to the first PLL circuit is supplied to the other input. A mixer, a bandpass filter supplied with the first intermediate frequency output from the first mixer, an output of the bandpass filter supplied to one input, and a second input supplied to the other input. Second loop connected to the PLL circuit of
A second mixer to which the output of the local oscillator is supplied, and an output terminal to which the second intermediate frequency output from the second mixer is supplied. The intermediate frequency of 1 is set low, the second intermediate frequency is set lower than the first intermediate frequency, and the bandwidth of the bandpass filter is 1
The frequency is narrower than the overall width of the plurality of segments included in the channel, and the frequency of the desired reception segment included in the one channel becomes the predetermined first intermediate frequency output from the first mixer. As described above, the high frequency signal receiving device is provided with the intermediate frequency control means for controlling the oscillation frequency of the first local oscillator, and the band width of the band pass filter is narrower than the entire width of the plurality of segments. Less signal energy will be transmitted thereafter. Therefore, distortion can be reduced. Further, the power of the signal to the next stage and thereafter is reduced, so that power saving can be achieved accordingly. Therefore, the battery life can be extended when used in a portable device or the like.

Further, since the band width of the bandpass filter is narrowed, the interference received from the adjacent channel is reduced.

Furthermore, since the first intermediate frequency is set higher than the frequency of the digital broadcast wave, it can be used with a margin within the range of high frequency characteristics of the parts used, low cost can be realized, and NF performance can be improved. A good high frequency signal receiving device can be obtained.

According to a thirteenth aspect of the present invention, there is provided a high frequency signal receiving device for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high frequency signal receiving device is an input to which the digital broadcast wave is input. Terminal, a tuning filter to which the signal input to this input terminal is connected, and an output signal of a local oscillator which is supplied to one input to the output of this tuning filter and loop-connected to the PLL circuit to the other input Is provided, a bandpass filter to which the intermediate frequency output from this mixer is supplied, and an output terminal to which the output of this bandpass filter is supplied, and the bandwidth of the bandpass filter is , The desired width of a segment included in one channel, which is narrower than the entire width of a plurality of segments included in the one channel. Is a high-frequency signal receiving device provided with an intermediate frequency control means for controlling the oscillation frequency of the local oscillator so that the frequency becomes the predetermined intermediate frequency output from the mixer, Since the width is narrower than the entire width of the plurality of segments, the signal energy transmitted to the subsequent stages is small. Therefore, distortion can be reduced. Further, the power of the signal to the next stage and thereafter is reduced, so that power saving can be achieved accordingly. Therefore, the battery life can be extended when used in a portable device or the like.

Further, since the band width of the bandpass filter is narrowed, the interference received from the adjacent channel is reduced.

Furthermore, since it is a single supermarket, the NF performance is improved and a compact and low-priced high frequency signal receiving device can be realized.

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram of a high frequency signal receiving apparatus according to Embodiment 1 of the present invention. In FIG. 1, the high frequency signal receiving apparatus of the present invention has an input terminal 31 to which a digital broadcast wave of approximately 90 MHz to 770 MHz is input, an amplifier 32 connected to the input terminal 31, and an output of the amplifier 32. The mixer 3 in which the output of the local oscillator 34, which is supplied to the input and is loop-connected to the PLL circuit 33, is connected to the other input.
5 is connected to the output of the mixer 35 and
A bandpass filter 36 that passes the intermediate frequency of
The mixer 3 in which the output of the bandpass filter 36 is connected to one input and the output of a local oscillator 38 loop-connected to the PLL circuit 37 is connected to the other input.
9 and an output terminal 40 to which the second intermediate frequency is supplied is connected to the output of the mixer 39.

The PLL circuits 33 and 37 are both connected to one crystal oscillator 41 and to the microcomputer 42. The microcomputer 42 is connected to the data terminal 43.

Here, the frequency of the digital broadcast wave 45 input to the input terminal 31 is approximately 90 as shown in FIG. 2 (a).
The frequency is from MHz to 770 MHz, and the first intermediate frequency output from the mixer 35 is set to 1205 MHz, which is higher than the input signal, as indicated by 46 in FIG. 2B.

Here, the first intermediate frequency is the local oscillator 3
By controlling the output frequency of No. 4 by the microcomputer 42 via the PLL circuit 33, channel selection is performed and the frequency of the segment desired to be received is the first intermediate frequency 1205MH in the same channel.
The oscillation frequency of the local oscillator 34 is set so as to be z. The first intermediate frequency is the local oscillator 34, P
The LL circuit 33 and the microcomputer 42 form the intermediate frequency setting means in the present invention.

The second intermediate frequency output from the mixer 39 is approximately 4 MHz as shown by 47 in FIG. 2 (c).
Is set to.

Here, the second intermediate frequency is the local oscillator 3
The oscillation frequency of the local oscillator 38 is set to be 4 MHz by controlling the output frequency of 8 by the microcomputer 42 via the PLL circuit 37.

The operation of the high frequency signal receiving apparatus configured as described above will be described below. Input terminal 31
In addition, as shown in FIG.
A digital broadcast wave of MHz is input. The digital broadcast wave 45 is mixed with the output of the local oscillator 34 by the mixer 35 and converted into an intermediate frequency 46 of 1205 MHz as shown in FIG. That is, it is a translation that is selected.

The intermediate frequency 46 output from the mixer 35 is passed through the filter 36 to the mixer 39.
2 is mixed with the signal output from the local oscillator 38 in FIG.
As shown in (c), it is converted to the intermediate frequency 47 of 4 MHz.

Although the output of the mixer 39 is 4 MHz in the present embodiment, the output is not limited to 4 MHz and may be 2 MHz or 1 MHz.

Here, the band width 50 of the band pass filter 36 is set to 0.43 MHz as shown in FIG. This is because only one segment is taken out of the digital broadcast wave shown in FIG. 11 or 12. In this way, only the desired segment is extracted, so that excess energy is not supplied to the subsequent circuits and distortion is reduced.

The band width 50 of the band-pass filter 36 is set to 3 segment width (approximately 1.5 MHz) in consideration of variations in parts and changes in external temperature, so that stable performance can be obtained. FIG. 4 shows an output waveform of the bandpass filter 36 output from the mixer 39 in this case.
Shown in.

FIG. 4A shows a case where the third segment 52 is selected. That is, the output frequency of the local oscillator 34 is controlled by the microcomputer 42 so that the center frequency of the third segment 52 becomes the intermediate frequency 1205 MHz.

Reference numeral 53 is an audio signal of an adjacent analog broadcast wave. Since the bandpass filter 36 of a narrow band having a narrow band width is used as described above, the audio signal 53 which is an interfering signal can be made sufficiently small.

FIG. 4B shows the case where the second segment 54 is selected, and FIG. 4C shows the case where the first segment 55 is selected. If you select the 1st segment 55,
The band-pass filter 36 has little effect of attenuating adjacent channels, and the level of the audio signal 53, which is an interfering signal, becomes high. However, even in this case, it is the same as the case of the conventional bandpass filter 6. When the other segment is selected, the effect of using the narrow band filter for the band pass filter 36 comes to appear sequentially.

Although the SAW (surface acoustic wave) filter is used as the bandpass filter 36 in the present embodiment, the bandpass filter is not limited to the SAW filter and may be a bandpass filter composed of a capacitor and an inductor. good. Further, a trap filter using a series circuit of an inductor and a capacitor formed in a pattern may be provided before or after the bandpass filter or one of them. 5 and 6 are examples in which a trap filter is inserted into the input of the first intermediate frequency filter (corresponding to the bandpass filter 36 in the first embodiment) 60. In FIG. 5, the bandpass filter 6 is provided between the input 61 and the output 62.
0 is connected. And this bandpass filter 6
An inductor 63 and a capacitor 64 formed in a pattern are connected in series between the input side of 0 and the ground to form a trap filter. The trap frequency is adjusted by laser trimming the adjusting portion 65 formed in the inductor 63.

FIG. 6 shows another example of the trap filter, in which a bandpass filter 60 is connected between an input 61 and an output 62. A pattern-formed inductor 66, a fixed capacitor 67, and a varicap diode 68 are connected in series between the input side of the bandpass filter 60 and the ground to form a trap filter. Reference numeral 69 denotes a resistor, which supplies a voltage from the terminal 70 to the varicap diode 68 to adjust the trap frequency.

Here, the inductor 6 used in FIGS.
The value of 3 or 66 is about 6 nH, the capacitor 64 is 3 pF, and is a trap filter of about 1.2 GHz. In addition, since the thickness of the printed circuit board used at this time is 1.164 mm and the relative dielectric constant is 4.4,
Inductors 63 and 66 have a length of 8 mm and a width of 0.3 mm
Becomes

As described above, according to the present embodiment, the band width of the band pass filter 36 is set to be narrower than the entire width of the plurality of segments, so that the signal energy to the subsequent stages is reduced and the distortion is reduced. can do. Also,
Since the power of the signal transmitted to the next stage and below is reduced,
Power consumption can be reduced accordingly. Therefore, the battery life can be extended when used in a portable device or the like.

Further, since the band width of the bandpass filter 36 is narrowed, the interference received from the adjacent channel is reduced.

Since the first intermediate frequency 46 is set higher than the frequency 45 of the digital broadcast wave, the image frequency does not interfere with the reception band.

Furthermore, since the reference frequency supplied to the PLL circuit 33 and the reference frequency supplied to the PLL circuit 37 are supplied from the same crystal oscillator 41, it is possible to achieve miniaturization and cost reduction. Can be realized.

The PLL circuit 33 and the PLL circuit 3
The microcomputer 7 is controlled by the microcomputer 42, which facilitates external control.

Furthermore, the amplifier 32 and the PLL circuit 33 are provided.
, Local oscillator 34, mixer 35, local oscillator 38
Since the PLL circuit 37 and the mixer 39 are integrated in the same package, it is possible to reduce the size and manage the parts and reduce the number of manufacturing steps. The microcomputer 42 can also be integrated in the same package.

(Second Embodiment) FIG. 7 is a block diagram of a high frequency signal receiving apparatus according to the second embodiment. The first embodiment is an up / down type double supermarket, whereas the second embodiment is different in that it is a down / down type double supermarket.

The second embodiment will be described below. In FIG. 7, the high frequency signal receiving apparatus of the present invention is a high frequency signal receiving apparatus for receiving a digital broadcast wave including a maximum of 13 segments (however, 7 channels are 8 segments) in one channel. The device is approximately 90M
Input terminal 71 to which digital broadcast wave of Hz to 770 MHz is input, and amplifier 7 connected to this input terminal 71
2, and a mixer 75 in which the output of the amplifier 72 is supplied to one input and the output of a local oscillator 74 loop-connected to the PLL circuit 73 is connected to the other input,
The bandpass filter 76 connected to the output of the mixer 75 and passing the first intermediate frequency, the mixer 77 having the output of the bandpass filter 76 connected to one input, and the mixer 77. An output terminal 78 to which the second intermediate frequency is supplied is connected to the output.

The other input of the mixer 77 is PL
A local oscillator 80 loop-connected to the L circuit 79 is connected via a frequency divider 81. Further, the PLL circuits 73 and 79 are both connected to one crystal oscillator 82,
The circuit 73 is connected to the microcomputer 83. The microcomputer 83 is connected to the data terminal 84. The PLL circuit 73 sets the oscillation frequency of the local oscillator 74 so that the signal of a desired specific segment is mixed by the mixer 75 and becomes 1205 MHz. Together with the microcomputer 83, the intermediate frequency setting in the present invention is set. Forming the means.

Here, the frequency 45 of the digital broadcast wave input to the input terminal 71 is approximately 90 as shown in FIG.
The frequency is from MHz to 770 MHz, and the first intermediate frequency output from the mixer 75 is set as low as 56 MHz as indicated by 49 in FIG. 2B.

The second intermediate frequency output from the mixer 77 is set to 4 MHz as indicated by 47 in FIG. 2 (c).

The operation of the high frequency signal receiving apparatus configured as described above will be described below. Input terminal 71
As shown in FIG.
A 70 MHz digital broadcast wave is input. The digital broadcast wave 45 is mixed with the output of the local oscillator 74 by the mixer 75 and converted into an intermediate frequency 49 of 56 MHz as shown in FIG. That is, it is a translation that is selected.

The intermediate frequency 49 output from the mixer 75 is passed through the filter 76 to the mixer 77.
Then, the local oscillator 80 is mixed with the signal output through the distributor 81 and converted into the intermediate frequency 47 of 4 MHz as shown in FIG. The parts not described are the same as those in the first embodiment.

In this embodiment, since the first intermediate frequency 49 is set lower than the frequency of the digital broadcast wave 45, it is possible to obtain a high frequency signal receiving device having good NF performance.

The output from the frequency divider 81 is 1201M.
Since the oscillation frequency of the local oscillator 80 is set to be Hz, the output of the local oscillator 74 does not interfere with the output of the local oscillator 80. What is important here is that the oscillation frequency of the local oscillator 80 is not an integral multiple of the local oscillator 74. If it is multiplied by an integer, its harmonics will interfere. Further, since the output of the local oscillator 80 is significantly different from the signal input to the input terminal 71, the output of the local oscillator 80 does not adversely affect the input terminal (antenna side) 71.

It is important that the frequency divider 81 is arranged close to the mixer 77. This is to prevent the distributed output of the distributor 81 from becoming an interfering wave and adversely affecting the input terminal 71 side.

(Third Embodiment) FIG. 8 is a block diagram of a high frequency signal receiving apparatus according to the third embodiment. The first embodiment is different from the up / down type double supermarket in that it is a single supermarket in the third embodiment.

A description will be given below. The high-frequency signal receiving apparatus in FIG. 8 is a high-frequency signal receiving apparatus that receives a digital broadcast wave containing a maximum of 13 segments in one channel, and the high-frequency signal receiving apparatus is approximately 90 MHz to 7 MHz.
Input terminal 91 for input of 70 MHz digital broadcast wave
An amplifier 90 connected to the input terminal 91, a tuning filter 92 connected to the output of the amplifier 90, an output of the tuning filter 92 is supplied to one input, and a PLL circuit is provided to the other input. A mixer 95 to which an output of a local oscillator 94 loop-connected to 93 is connected, a bandpass filter 96 connected to the output of the mixer 95 and passing an intermediate frequency, and an output of the bandpass filter 96. It has an output terminal 97 connected to it.

A microcomputer 98 is connected to the PLL circuit 93, and the microcomputer 98 is connected to the data terminal 99.

Here, the frequency of the digital broadcast wave 45 input to the input terminal 91 is the same as in the first embodiment, as shown in FIG.
As shown in (a), it is approximately 90 MHz to 770 MHz, and the intermediate frequency output from the mixer 95 is directly converted to 4 Hz as indicated by 47 in FIG. 2 (c), as in the first embodiment. Here, the intermediate frequency is determined by controlling the output frequency of the local oscillator 94 by the microcomputer 98, and the microcomputer 98 controls the desired reception channel and the desired reception segment of this desired reception channel to be 4 MHz. .

The operation of the high frequency signal receiving device configured as described above will be described below. Input terminal 91
In addition, as shown in FIG.
A digital broadcast wave of MHz is input. The digital broadcast wave 45 is mixed with the output of the local oscillator 94 by the mixer 95, and then is output through the bandpass filter 96 to the output terminal 97.
Is output from.

Here, the number of segments included in one channel of digital broadcast wave 45 is the same as in the first embodiment. Therefore, the microcomputer 98 controls the oscillation frequency of the local oscillator 94 to select a channel and also controls the tuning filter 90. It should be noted that the center frequency of the tuning filter 92 is also controlled by the output of the PLL circuit 93 to roughly select the channel.

The parts not described in the present embodiment are the same as those in the first embodiment.

[0073]

As described above, according to the high frequency signal receiving apparatus of the present invention, the bandpass filter has a band width narrower than the entire width of a plurality of segments, so that the signal energy transmitted to the subsequent stages is small. Become. Therefore, distortion can be reduced. Further, the power of the signal to the next stage and thereafter is reduced, so that power saving can be achieved accordingly. Therefore,
The battery life can be extended by using it in portable devices and the like.

Further, since the band width of the bandpass filter is narrowed, the interference received from the adjacent channel can be reduced and correct reception can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram of a high frequency signal receiving device according to a first embodiment of the present invention.

2A is a digital broadcast wave signal diagram of the high-frequency signal receiving device according to the first, second, and third embodiments, and FIG. 2B is a first intermediate frequency of the high-frequency signal receiving device according to the first and second embodiments. 2C is a signal diagram of the output frequency of the high-frequency signal receiving device according to the first, second, and third embodiments.

FIG. 3 is a passband characteristic diagram of the same bandpass filter.

FIG. 4 (a) is the same as the first operation explanatory diagram near the intermediate frequency, FIG. 4 (b) is the same, second operation explanatory diagram near the intermediate frequency is the same, and FIG. Illustration

FIG. 5 is a first block diagram of the same trap filter.

FIG. 6 is a second block diagram of the same trap filter.

FIG. 7 is a block diagram of a high frequency signal receiving apparatus according to the second embodiment.

FIG. 8 is a block diagram of a high frequency signal receiving apparatus according to the third embodiment.

FIG. 9 is a block diagram of a conventional high-frequency signal receiving device.

FIG. 10A is the same as the digital broadcast wave signal diagram of the high frequency signal receiving device, FIG. 10B is the same, FIG. 10C is the signal diagram of the first intermediate frequency, and FIG.

FIG. 11 is the same as the first segment included in the channel.
Illustration of

FIG. 12 is the second segment included in the channel.
Illustration of

[Explanation of symbols]

31 input terminals 33 PLL circuit 34 Local oscillator 35 mixer 36 bandpass filter 40 output terminals 42 Microcomputer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Haruki Ohwaki             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Ippei Jinno             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5C025 AA25                 5J103 AA03 AA09 BA00 DA03 DA05                       DA06 DA16 EA08                 5K020 AA01 DD01 DD13 EE04 GG01                       HH13 NN10                 5K022 FF00 GG00

Claims (13)

[Claims] 1. A high frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high frequency signal receiving apparatus has an input terminal to which the digital broadcast wave is input and an input terminal to the input terminal. The input signal is supplied to one input and the other input is PL
A mixer to which the output signal of the local oscillator loop-connected to the L circuit is supplied, a bandpass filter to which the intermediate frequency output from this mixer is supplied, and an output terminal to which the output of this bandpass filter is supplied. And a band width of the band pass filter is narrower than an entire width of a plurality of segments included in the one channel,
A high frequency signal provided with an intermediate frequency control means for controlling the oscillation frequency of the local oscillator so that the frequency of the desired segment included in the one channel becomes the predetermined intermediate frequency output from the mixer. Receiver. 2. The high frequency signal receiving device according to claim 1, wherein the bandpass filter is formed of a SAW filter. 3. The high frequency signal receiving device according to claim 1, wherein the bandpass filter has a bandwidth of approximately one segment. 4. The high frequency signal receiving apparatus according to claim 1, wherein the bandpass filter has a bandwidth of approximately 3 segments. 5. The high frequency signal receiving device according to claim 4, wherein a trap filter for removing an interference frequency is inserted in series with the bandpass filter. 6. The high frequency signal receiver according to claim 5, wherein the trap frequency of the trap filter is adjustable. 7. The high frequency signal receiving apparatus according to claim 6, wherein the trap filter is formed by a series connection circuit of an inductor and a capacitor formed by a pattern, and the inductance value of the inductor is adjusted by laser trimming. 8. The trap filter is formed by a series connection circuit of an inductor and a capacitor formed by a pattern, and the capacitor uses a varicap diode, and the capacitance value is adjusted by applying a voltage from the outside. The high frequency signal receiving device according to. 9. At least a mixer, a local oscillator, and P
The LL circuit and the LL circuit are integrated in the same package.
The high frequency signal receiving device according to. 10. The high frequency signal receiving device according to claim 1, wherein the PLL circuit is controlled by a microcomputer. 11. A high-frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high-frequency signal receiving apparatus has an input terminal to which the digital broadcast wave is input and an input terminal to the input terminal. The input signal is supplied to one input and the other input receives the first signal.
A first mixer to which an output signal of a first local oscillator loop-connected to the PLL circuit of, and a filter to which a first intermediate frequency output from the first mixer is supplied, A second mixer in which the output of the filter is supplied to one input and the other input is supplied with the output of a second local oscillator loop-connected to a second PLL circuit; An output terminal to which a second intermediate frequency output from the receiver is supplied, the first intermediate frequency being set higher than the frequency of the digital broadcast wave, and the second intermediate frequency being the digital broadcast wave. , The band width of the bandpass filter is set to be narrower than the entire width of the plurality of segments included in the one channel, and the desired reception segment included in the one channel is set. Frequency signal provided with intermediate frequency control means for controlling the oscillation frequency of the first local oscillator so that the frequency of the first local oscillator is the predetermined first intermediate frequency output from the first mixer. Receiver. 12. A high-frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high-frequency signal receiving apparatus has an input terminal to which the digital broadcast wave is input and an input terminal to the input terminal. The input signal is supplied to one input and the other input receives the first signal.
A first mixer to which an output signal of a first local oscillator loop-connected to the PLL circuit is supplied, and a bandpass filter to which a first intermediate frequency output from the first mixer is supplied. , The output of this bandpass filter is supplied to one input and the second PLL is supplied to the other input.
A second mixer supplied with an output of a second local oscillator loop-connected to the circuit; and an output terminal supplied with a second intermediate frequency output from the second mixer, The first intermediate frequency is set to be lower than the frequency of the digital broadcast wave, the second intermediate frequency is set to be further lower than the first intermediate frequency, and the bandwidth of the bandpass filter is set to one of the one channel. Is narrower than the entire width of the plurality of segments included in the first segment, and the frequency of the desired segment included in the one channel is output from the first mixer.
A high-frequency signal receiving apparatus provided with an intermediate frequency control means for controlling the oscillation frequency of the first local oscillator so that the intermediate frequency becomes the intermediate frequency. 13. A high frequency signal receiving apparatus for receiving a digital broadcast wave including a plurality of segments in one channel, wherein the high frequency signal receiving apparatus has an input terminal to which the digital broadcast wave is input and an input terminal to the input terminal. A tuning filter to which an input signal is connected, and one output is supplied to the output of this tuning filter and PL is supplied to the other input.
A mixer to which the output signal of the local oscillator loop-connected to the L circuit is supplied, a bandpass filter to which the intermediate frequency output from this mixer is supplied, and an output terminal to which the output of this bandpass filter is supplied. And a band width of the band pass filter is narrower than an entire width of a plurality of segments included in the one channel,
A high frequency signal provided with an intermediate frequency control means for controlling the oscillation frequency of the local oscillator so that the frequency of the desired segment included in the one channel becomes the predetermined intermediate frequency output from the mixer. Receiver.