JP4845632B2 - Jamming signal elimination apparatus and jamming signal elimination method - Google Patents

Description

  The present invention relates to an interference signal removing apparatus and an interference signal removing method.

  Conventionally, various techniques have been proposed for removing interference caused by adjacent channels in direct conversion reception adopted in many mobile communication terminal devices such as radio broadcast reception and mobile phones. In such a technique, first, a high frequency signal received by an antenna is in a frequency range far away from a frequency range that can be detected for the received high frequency signal, and the center frequency of the broadcast wave from the desired channel is a predetermined frequency ( In direct conversion reception, frequency conversion is performed so that frequency = 0). Such frequency conversion is generally performed by superheterodyne mixing of a local oscillation signal having a frequency determined according to the type of a desired channel and a received high-frequency signal.

  Thereafter, using a variable filter that can change the frequency band of the signal to be passed, the presence / absence of the interference wave and the frequency band in which the interference wave exists are detected. Based on the result of the detection, a signal from which the influence of the interference wave is removed or reduced is extracted. (See Patent Literature 1 and Patent Literature 2: hereinafter referred to as “conventional example”).

Japanese Patent No. 3335414 Japanese Patent No. 3568102

  In the conventional technology described above, the presence or absence of an interfering wave and the frequency band where the interfering wave exists are detected using a variable filter. However, if a variable filter is configured, the circuit scale increases and the amount of digital computation increases. Furthermore, when the frequency band of the disturbing wave is not constant, it becomes difficult to design a variable filter for detecting the disturbing wave. Eliminating such a situation is one of the problems to be solved by the present invention.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an interference signal removing device and an interference signal removing method capable of easily removing an interference signal included in an input signal.

The invention according to claim 1 is based on a first shift frequency and a first shift direction that are shift amounts of a frequency related to a first quadrature signal that is a quadrature signal of the first in-phase signal and the first in-phase signal. The frequency of the frequency component of the first in-phase signal is shifted by the first shift frequency in the first shift direction, and the frequency of the frequency component of the first quadrature signal is the first shift. First frequency shift means for generating a second quadrature signal shifted in the direction by the first shift frequency; and a signal in a predetermined first frequency range included in the second in-phase signal and the second quadrature signal First signal detecting means for detecting a component; removing the signal component in the first frequency range from the pair of the first in-phase signal and the first quadrature signal and from the second in-phase signal and the second quadrature signal. Third in-phase signal and First signal selection means for selectively outputting any one of a pair of a fourth in-phase signal and a fourth quadrature signal corresponding to three quadrature signals as a fifth in-phase signal and a fifth quadrature signal; Based on the detection means by the detection means, a first determination that is a determination of the presence or absence of an interfering signal in the first frequency range of at least one of the second in-phase signal and the second quadrature signal is performed, and the first determination If the result is affirmative, the selection output of the fourth in-phase signal and the fourth quadrature signal pair is commanded to the first signal selection means, and the result of the first determination is negative. manner and which was the case, the selection outputs of pairs of the first phase signal and the first quadrature signal and a control means for instructing to the first signal selecting means; wherein the control means, wherein Frequency component of signal input to first frequency shift means The detection result by the first signal detection means is collected while changing the frequency shift frequency, the frequency distribution range of the interference signal is specified based on the collected detection result, and the specified interference signal An interference signal removing device that determines the first shift frequency and the first shift direction based on a frequency distribution range .

According to a thirteenth aspect of the present invention, the first in-phase signal and the first in-phase signal are orthogonal signals based on a shift frequency and a shift direction that are frequency shift amounts related to a first quadrature signal that is a quadrature signal of the first in-phase signal. A second in-phase signal in which the frequency component of the phase signal is shifted in the shift direction by the shift frequency, and a second in-phase signal in which the frequency component of the first quadrature signal is shifted in the shift direction by the shift frequency. An interference signal removing apparatus comprising: frequency shift means for generating two quadrature signals; and signal detection means for detecting signal components in a predetermined frequency range included in the second in-phase signal and the second quadrature signal. An interference signal removal method used, wherein the signal detection means changes the frequency shift frequency of the frequency component of the signal input to the frequency shift means. Collecting detection results, identifying a frequency distribution range of the jamming signal based on the collected detection results, and determining the shift frequency and the shift direction based on the frequency distribution range of the identified jamming signal And determining whether or not there is an interfering signal in the frequency range of at least one of the second in-phase signal and the second quadrature signal based on the detection result by the signal detecting means , and the result of the determination is If positive, a fourth in-phase signal corresponding to the third in-phase signal and the third quadrature signal and the third in-phase signal obtained by removing signal components in the frequency range from the second in-phase signal and the second quadrature signal; A first signal selecting step for selecting and outputting a pair of four quadrature signals; and a first signal for selecting and outputting a pair of the first in-phase signal and the first quadrature signal when the result of the determination is negative. 2 signal selection A disturbing signal eliminating method characterized by comprising a; and process.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

[First Embodiment]
First, a first embodiment of the present invention will be described with reference to FIGS.

<Configuration>
FIG. 1 is a block diagram illustrating a schematic configuration of an interference signal removing device 100A according to the present embodiment. This interference signal removing device 100A is a device that removes the interference signal in the signal C0 output from the signal source 910. As shown in FIG. 1, the interference signal removing device 100A is configured to generate orthogonal signals as signal generation means. 110, a signal detection unit 120A, a control unit 130A as a control unit, and a signal selection unit 140 as a first signal selection unit.

In the present embodiment, the signal C0 is represented by the following equation (1) in order to simplify the description.
C0 (t) ∝F (t) · cos (ω _C · t + φ) (1)

  Examples of the signal represented by the equation (1) include an intermediate frequency signal output from a tuner unit in a general radio receiver.

The quadrature signal generation unit 110 includes a quadrature modulator 111 as shown in FIG. The quadrature signal generation unit 110 is a signal in phase with the signal C0, and is a signal obtained by quadrature modulation of the signal C1 (first in-phase signal) expressed by the following equation (2 ) and the signal C0. The signal S1 (first orthogonal signal) represented by the equation (3) is generated. The generated signals C1 and S1 are output to the signal detection unit 120A and the signal selection unit 140.
C1 (t) = F (t) · cos (ω _C · t + φ) (2)
S1 (t) = F (t) · sin (ω _C · t + φ) (3)

The signal detection unit 120A detects a signal component in a desired frequency band in the signals C1 and S1 output from the orthogonal signal generation unit 110 under the control of the control unit 130A, and the desired signal in the signals C1 and S1. The signal components in the frequency band other than the frequency band are output as signals C6 (fourth in-phase signal) and S6 (fourth orthogonal signal) . The signal detector 120A will be described later.

  The control unit 130A includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), peripheral circuits, and the like. An operation input device such as a keyboard (not shown) is connected to the control unit 130A.

The control unit 130A changes the shift angular frequency ω _SH corresponding to the amount of frequency shift related to the signals C1 and S1 according to the designation of the frequency band of the signal to be detected whether there is an interference signal input to the operation input device. The designated SFA is sent to the signal detection unit 120A, and the shift directions designated to the shift calculation unit 220A and the reverse shift calculation unit 250A described later are sent to the signal detection unit 120A as shift direction designations SD1 and SD2. Control unit 130A receives detection results D1 and D2 from signal detection unit 120A. Then, control unit 130A determines the presence / absence of an interfering signal based on detection results D1 and D2, and designates a signal to be selected and output to signal selection unit 140 based on the result of the determination based on signal selection control signal SLT. To do.

As shown in FIG. 3, the signal detection unit 120A includes a local oscillation unit 210, a shift calculation unit 220A, a filter unit 230, a detection unit 240, and an inverse shift calculation unit 250A. Here, the local oscillation unit 210 and the shift calculation unit 220A constitute a first frequency shift means. The filter unit 230 and the detection unit 240 constitute a first signal detection unit. The local oscillating unit 210 and the inverse shift calculating unit 250A constitute a first inverse frequency shift means.

As shown in FIG. 4, the local oscillation unit 210 includes an oscillator 211 and a 90 ° phase shifter 212. Here, the oscillator 211 includes a voltage-controlled oscillation element and the like, and generates a signal having an angular frequency ω _SH corresponding to the shift frequency designation SFA in accordance with the shift frequency designation SFA from the control unit 130A. The 90 ° phase shifter 212 shifts the phase of the signal generated by the oscillator 211 by 90 °.

Using the oscillator 211 and the 90 ° phase shifter 212, the local oscillation unit 210 is a signal C2 expressed by the following equation (4) and a quadrature signal of the signal C2, and the following ( 5) A signal S2 represented by the equation is generated and output to the shift calculation unit 220A.
C2 (t) = G · cos ω _SH · t (4)
S2 (t) = G · sinω _SH · t (5)
Here, G is a constant.

  As shown in FIG. 5, the shift calculation unit 220 </ b> A includes multipliers 221 to 224. The shift calculation unit 220A includes adders / subtracters 226 and 227.

  Each of the multipliers 221 to 224 calculates a product at each time point of the signal received at the terminal A and the signal received at the terminal B, and outputs the calculation result from the terminal C. That is, the multiplier 221 calculates and outputs a product at each time point of the signal C1 output from the orthogonal signal generation unit 110 and the signal C2 output from the local oscillation unit 210. The multiplier 222 calculates and outputs a product at each time point of the signal S1 output from the quadrature signal generation unit 110 and the signal S2 output from the local oscillation unit 210. The multiplier 223 calculates and outputs a product at each time point of the signal S1 output from the quadrature signal generation unit 110 and the signal C2 output from the local oscillation unit 210. The multiplier 224 calculates and outputs a product at each time point of the signal C1 output from the orthogonal signal generation unit 110 and the signal S2 output from the local oscillation unit 210.

  The adder / subtractor 226 receives the calculation result from the multiplier 221 at the terminal I1 and the calculation result from the multiplier 222 at the terminal I2. Then, according to the shift direction designation SD1 from the control unit 130A, the difference or sum at each time point between the signal received at the terminal I1 and the signal received at the terminal I2 is calculated.

Specifically, when a frequency shift to the + side is designated by the shift direction designation SD1 from the control unit 130A, the adder / subtractor 226 changes the value of the signal received at the terminal I2 from the value of the signal received at the terminal I1. Subtract. As a result, a signal represented by the following equation (6 ) is generated as a signal C3 (second in-phase signal) .
C3 (t) = C1 (t) · C2 (t) −S1 (t) · S2 (t)
= G · F (t) · cos ((ω _C + ω _SH ) · t + φ) (6)

That is, a signal that is frequency-shifted to the + side by the angular frequency ω _{SH with} respect to the signal C1 is generated as the signal C3. The signal C3 generated in this way is output from the terminal O of the adder / subtractor 226 to the filter unit 230.

Further, when the frequency shift to the negative side is designated by the shift direction designation SD1 from the control unit 130A, the adder / subtracter 226 adds the value of the signal received at the terminal I2 to the value of the signal received at the terminal I1. As a result, a signal represented by the following equation (7) is generated as the signal C3.
C3 (t) = C1 (t) · C2 (t) + S1 (t) · S2 (t)
= G · F (t) · cos ((ω _C −ω _SH ) · t + φ) (7)

That is, a signal that is frequency-shifted to the minus side by the angular frequency ω _{SH with} respect to the signal C1 is generated as the signal C3. The signal C3 generated in this way is output from the terminal O of the adder / subtractor 226 to the filter unit 230.

  The adder / subtractor 227 receives the calculation result from the multiplier 223 at the terminal I1 and the calculation result from the multiplier 224 at the terminal I2. Then, according to the shift direction designation SD1 from the control unit 130A, the sum or difference at each time point between the signal received at the terminal I1 and the signal received at the terminal I2 is calculated.

Specifically, when a frequency shift to the + side is designated by the shift direction designation SD1 from the control unit 130A, the adder / subtractor 227 adds the value of the signal received at the terminal I2 to the value of the signal received at the terminal I1. to add. As a result, a signal represented by the following equation (8 ) is generated as a signal S3 (second orthogonal signal) .
S3 (t) = S1 (t) · C2 (t) + C1 (t) · S2 (t)
= G · F (t) · sin ((ω _C + ω _SH ) · t + φ) (8)

That is, a signal that is frequency-shifted to the + side by the angular frequency ω _{SH with} respect to the signal S1 is generated as the signal S3. The signal S3 thus generated is output from the terminal O of the adder / subtractor 227 to the filter unit 230.

Further, when a frequency shift to the negative side is designated by the shift direction designation SD1 from the control unit 130A, the adder / subtracter 227 subtracts the value of the signal received at the terminal I2 from the value of the signal received at the terminal I1. As a result, a signal represented by the following equation (9) is generated as the signal S3.
S3 (t) = S1 (t) · C2 (t) −C1 (t) · S2 (t)
= G · F (t) · sin ((ω _C −ω _SH ) · t + φ) (9)

That is, a signal that is frequency-shifted to the minus side by the angular frequency ω _{SH with} respect to the signal S1 is generated as the signal S3. The signal S3 thus generated is output from the terminal O of the adder / subtractor 227 to the filter unit 230.

As illustrated in FIG. 6, the filter unit 230 includes a filter 231, a filter 232, a filter 233, and a filter 234. Here, the filter 231 and the filter 232 have the same predetermined transmission characteristic for the same frequency component. The filter 231 selectively passes a predetermined frequency component in the signal C3 from the shift calculation unit 220A, and outputs it to the inverse shift calculation unit 250A as a signal C4 (third in-phase signal) . Further, the filter 232 selectively passes a predetermined frequency component in the signal S3 from the shift calculation unit 220A, and outputs it to the inverse shift calculation unit 250A as a signal S4 (third orthogonal signal) .

These signals C4 and S4 are expressed by the following equations (10) and (11) when the shift to the positive side is designated by the shift direction designation SD1.
C4 (t) = G · F ′ (t) · cos ((ω _C + ω _SH ) · t + φ) (10)
S4 (t) = G · F ′ (t) · sin ((ω _C + ω _SH ) · t + φ) (11)

Further, the signals C4 and S4 are expressed by the following equations (12) and (13) when the frequency shift to the negative side is designated by the shift direction designation SD1.
C4 (t) = G · F ′ (t) · cos ((ω _C −ω _SH ) · t + φ) (12)
S4 (t) = G · F ′ (t) · sin ((ω _C −ω _SH ) · t + φ) (13)

  In addition, the filter 233 and the filter 234 have a transmission characteristic that blocks signals in the frequency band that the filters 231 and 232 pass and transmits signals in the frequency band that the filters 231 and 232 block. The filter 233 selectively passes a frequency component other than the predetermined frequency component in the signal C3 from the shift calculation unit 220A, and outputs it as the signal C5 to the detection unit 240. In addition, the filter 234 selectively passes a frequency component other than the predetermined frequency component in the signal S3 from the shift calculation unit 220A, and outputs it as the signal S5 to the detection unit 240.

These signals C5 and S5 are expressed by the following equations (14) and (15) when the shift to the positive side is designated by the shift direction designation SD1.
C5 (t) = G · F ″ (t) · cos ((ω _C + ω _SH ) · t + φ) (14)
S5 (t) = G · F ″ (t) · sin ((ω _C + ω _SH ) · t + φ) (15)
Here, F ″ (t) = F (t) −F ′ (t)

Further, the signals C5 and S5 are expressed by the following equations (16) and (17) when the frequency shift to the negative side is designated by the shift direction designation SD1.
C5 (t) = G · F ″ (t) · cos ((ω _C −ω _SH ) · t + φ) (16)
S5 (t) = G · F ″ (t) · sin ((ω _C −ω _SH ) · t + φ) (17)

The filters 231, 232, 233, and 234 satisfy a condition that the transmission characteristics of the filters 231 and 232 and the transmission characteristics of the filters 233 and 234 conflict with each other as described above. BPF) and high pass filter (HPF), and any combination thereof. In this embodiment, a low-pass filter having transmission characteristics (cutoff angular frequency = ω _HP ) as shown in FIG. 7 is adopted as the filter 231 and the filter 232, and the filter 233 and the filter 234 are shown in FIG. A high-pass filter having a transmission characteristic (cutoff angular frequency = ω _HP ) as shown in FIG. Here, the low-pass filters 231 and 232 and the high-pass filters 233 and 234 are separately provided. For example, only the low-pass filters 231 and 232 are prepared as filters, and the signals C3 (t) to C4 (t) are prepared. Can be subtracted to obtain signal C5 (t), and signal S4 (t) can be subtracted from signal S3 (t) to obtain signal S5 (t). Further, only high-pass filters 233 and 234 are prepared as filters, and the signal C4 (t) is obtained by subtracting the signal C5 (t) from the signal C3 (t), and the signal S5 (t) is obtained from the signal S3 (t). Can be subtracted to obtain the signal S4 (t).

  As shown in FIG. 9, the detection unit 240 includes a signal detector 241 and a signal detector 242. The signal detector 241 detects the signal C5 from the filter unit 230, and outputs the detection result D1 to the control unit 130A. In addition, the signal detector 242 detects the signal S5 from the filter unit 230, and outputs the signal S5 to the control unit 130A as the detection result D2.

As shown in FIG. 10, the inverse shift calculation unit 250A includes multipliers 251 to 254 similar to the multipliers 221 to 224 in the shift calculation unit 220A, and adders / subtracters similar to the adders / subtracters 226 and 227 in the shift calculation unit 220A. 256, 257. And the reverse shift calculation part 250A is comprised similarly to the shift calculation part 220A. The multipliers 251 to 254 output a result obtained by multiplying the coefficient (1 / G ² ) in consideration of the constant G in the above-described equations (4) and (5).

  For this reverse shift calculation unit 250A, the control unit 130A designates a shift direction opposite to the shift direction designated by the shift direction designation SD1 described above by the shift direction designation SD2. . That is, when a shift in the + direction is designated by the shift direction designation SD1, a shift in the-direction is designated by the shift direction designation SD2. When a shift in the-direction is designated by the shift direction designation SD1, a shift in the + direction is designated by the shift direction designation SD2. As a result, the inverse shift calculation unit 250A performs a frequency shift on the signals C4 and S4 from the filter unit 230 that is opposite to the frequency shift performed by the shift calculation unit 220A on the signals C1 and S1.

Specifically, when the frequency shift to the + side is designated by the shift direction designation SD1 from the control unit 130A, when the frequency shift to the-side is designated by the shift direction designation SD2, the following (18 ) And (19) are generated as signals C6 and S6.
C6 (t) = (C4 (t) · C2 (t) + S4 (t) · S2 (t)) / G ²
= F ′ (t) · cos (ω _C · t + φ) (18)
S6 (t) = (S4 (t) · C2 (t) −C4 (t) · S2 (t)) / G ²
= F '(t) · sin (ω _C · t + φ) (19)

In addition, when the frequency shift to the − side is designated by the shift direction designation SD2 in accordance with the designation of the frequency shift to the − side by the shift direction designation SD1 from the control unit 130A, the following (20) and ( 21) Generated as signals C6 and S6 expressed by the equation.
C6 (t) = (C4 (t) · C2 (t) −S4 (t) · S2 (t)) / G ²
= F ′ (t) · cos (ω _C · t + φ) (20)
S6 (t) = (S4 (t) · C2 (t) + C4 (t) · S2 (t)) / G ²
= F '(t) · sin (ω _C · t + φ) (21)

  That is, in the reverse shift calculation unit 250A, the signals C6 and S6 are generated in which the frequency components in the signals C4 and S4 are returned to the frequencies they had at the time of the signals C1 and S1 (that is, the signal C0). . Then, the signals C6 and S6 are output from the reverse shift calculation unit 250A to the signal selection unit 140.

The signal selection unit 140 includes two selector elements (not shown) with two inputs and one output. The signal selection unit 140 selects one of the pair of the signals C1 and S1 and the pair of the signals C6 and S6 according to the selection output designation by the signal selection control signal SLT from the control unit 130A, and outputs the signal C7 (the fifth in-phase signal). ), and outputs it as S7 (fifth quadrature signal). The signals C7 and S7 are output from the output terminals 150 ₁ and 150 ₂ to the outside of the apparatus.

<Operation>
Next, the interference signal removal operation in the interference signal removal device 100A configured as described above will be described. In the following description, the signal C0 from the signal source 910 mainly focuses on the case where the interference signal NZ is included in addition to the desired signal SG as shown in FIG. I will explain.

First, according to the command input of the shift angular frequency ω _SH corresponding to the frequency shift amount from the operation input device (not shown), the control unit 130A determines the shift angular frequency ω _SH by the shift frequency designation SFA and the local part of the signal detection unit 120A. Notify the oscillator 210. As a result, the local oscillating unit 210 generates signals C2 and S2 having the angular frequency ω _SH (see the above-described equations (4) and (5)).

  The control unit 130A designates the frequency shift direction in the shift calculation unit 220A and the reverse shift calculation unit 250A by the shift direction designations SD1 and SD2. As described above, the shift direction designated by the shift direction designation SD1 and the shift direction designated by the shift direction designation SD2 are opposite to each other.

  On the other hand, the quadrature signal generation unit 110 generates the signal C1 and the quadrature signal S1 of the signal C1 from the signal C0 from the signal source 910 (see the above-described equations (2) and (3)). The orthogonal signal generation unit 110 sends the signals C1 and S1 thus generated to the shift calculation unit 220A.

As a result, the shift calculation unit 220A generates signals C3 and S3 that are frequency-shifted by the angular frequency ω _SH in the shift direction designated by the shift direction designation SD1 with respect to the signals C1 and S1. An example of the signals C3 and S3 generated in this way is shown in FIG. FIG. 11B shows an example in which the shift direction designated by the shift direction designation SD1 is the-direction.

The signals C3 and S3 generated in this way are signals C5 and S5 (see FIG. 11C) having an angular frequency larger than the angular frequency ω _HP toward the detection unit 240 in the filter unit 230, and an inverse shift calculation unit 250A. The signals are separated into signals C4 and S4 (see FIG. 12A) having an angular frequency equal to or lower than the angular frequency ω _HP toward the head. Then, the signals C4 and S4 are subjected to a frequency shift opposite to the frequency shift performed by the shift calculation unit 220A described above in the reverse shift calculation unit 250A to generate signals C6 and S6 (FIG. 12 ( B)).

On the other hand, the signals C5 and S5 are received and detected by the detection unit 240. As a result, when the shift direction designated by the shift direction designation SD1 is the + direction, the frequency corresponding to an angular frequency higher than the angular frequency (ω _HP −ω _SH ) in the input signal C0 from the signal source 910. The detection unit 240 detects a signal corresponding to the band signal component. When the shift direction designated by the shift direction designation SD1 is the-direction, the frequency band corresponding to the angular frequency higher than the angular frequency (ω _HP + ω _SH ) in the input signal C0 from the signal source 910 is used. The detection unit 240 detects a signal corresponding to the signal component. The detection results in the detection unit 240 are sent to the control unit 130A as signals D1 and D2.

  Control unit 130A determines whether or not an interference signal is included in signals C5 and S5 based on signals D1 and D2. This determination is performed by determining whether at least one of the signals D1 and D2 is greater than or equal to a predetermined value, for example.

As a result of the determination of the presence / absence of the interference signal, when it is determined that the interference signals are included in the signals C5 and S5, the control unit 130A selects and outputs the signals C6 and S6 to the signal selection unit 140. What to do is specified by the signal selection control signal SLT. As a result, after the signals C6 and S6 are selected from the signal selection unit 140, they are output from the output terminals 150 ₁ and 150 ₂ as the output signals C7 and S7.

On the other hand, as a result of the determination of the presence / absence of the interference signal, if it is determined that the interference signals are not included in the signals C5 and S5, the control unit 130A sends the signals C1 and S1 to the signal selection unit 140. It is designated by the signal selection control signal SLT that it should be selectively output. As a result, after the signals C1 and S1 are selected from the signal selection unit 140, they are output from the output terminals 150 ₁ and 150 ₂ as the output signals C7 and S7.

  As described above, in this embodiment, the in-phase signal C1 of the signal C0 from the signal source 910 and its quadrature signal S1, and the local oscillation signal C2 having the shift frequency specified by the control unit 130A and the quadrature signal S2 are used. Based on this, signals C3 and S3 are generated by shifting the signals C1 and S1 by the shift frequency in the shift direction designated by the control unit 130A. Subsequently, the presence or absence of an interference signal is detected by extracting and detecting a fixed frequency band in the signals C3 and S3 with a fixed filter. Then, based on the detection result of the presence / absence of the interfering signal, either the pair of the signals C1 and S1 or the pair of the signals C6 and S6 from which the signal component in the fixed frequency band is removed is removed from the interfering signal. Assume that the output signal of the device 100A. Therefore, the interference signal in the signal C0 from the signal source 910 can be easily removed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference mainly to FIGS.

<Configuration>
As shown in FIG. 13, the interference signal removal device 100B of the present embodiment includes a signal detection unit 120B instead of the signal detection unit 120A, compared to the interference signal removal device 100A of the first embodiment described above, The only difference is that a control unit 130B is provided instead of the control unit 130A. Here, the control unit 130B specifies the positive shift frequency by the shift frequency designation SFA and designates the shift direction by the shift direction designations SD1 and SD2, whereas the control unit 130B is coded by the shift frequency designation SFB. By designating the attached shift frequency, the shift frequency and the shift direction are designated.

  As shown in FIG. 14, the signal detection unit 120B includes a shift calculation unit 220B instead of the shift calculation unit 220A, as compared to the signal detection unit 120A, and a reverse shift calculation instead of the reverse shift calculation unit 250A. Only the point provided with the part 250B is different. Here, as shown in FIG. 15, the shift calculation unit 220 </ b> B includes a subtracter 228 instead of the adder / subtractor 226, and an adder instead of the adder / subtractor 227, as compared with the shift calculation unit 220 </ b> A described above. Only the point provided with 229 is different. Further, as shown in FIG. 16, the inverse shift calculation unit 250B includes an adder 258 instead of the adder / subtractor 256, and a subtractor instead of the adder / subtractor 257, as compared with the shift calculation unit 250A described above. Only the point provided with 259 is different.

<Operation>
In the interference signal removing device 100B configured as described above, the control unit 130B performs a signed shift angle by a shift frequency designation SFB according to a frequency shift amount and a shift direction command input from an operation input device (not shown). The frequency ω _SH is sent to the signal detector 120B. Thereafter, the interference signal removing operation is performed in the same manner as in the case of the above-described interference signal removing apparatus 100A.

  Therefore, in this embodiment, as in the case of the first embodiment, the in-phase signal C1 of the signal C0 from the signal source 910 and its quadrature signal S1 are frequency-shifted, and then the fixed frequency band is fixed. The presence or absence of an interference signal is detected by extracting and detecting with a filter. Then, based on the detection result of the presence / absence of the interfering signal, either the pair of the signals C1 and S1 or the pair of the signals C6 and S6 from which the signal component in the fixed frequency band is removed is removed from the interfering signal. Assume that the output signal of the device 100B. Therefore, the interference signal in the signal C0 from the signal source 910 can be easily removed.

  Further, since it is not necessary to switch the shift direction command as in the case of the first embodiment for switching the shift direction, the shift direction is continuously changed from the − direction to the + direction or from the + direction to the − direction. It is possible to easily control the change.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference mainly to FIG. 17 and FIG.

<Configuration>
As shown in FIG. 17, the interference signal removal device 100C of the present embodiment is different from the interference signal removal device 100A of the first embodiment described above only in that a control unit 130C is provided instead of the control unit 130A. ing. The control unit 130C automatically changes the shift angular frequency ω _SH in consideration of the detection result by the detection unit 240.

In the present embodiment, in the spectrum distribution of the signal C0 from the signal source 910, when a peak of an interference signal exists in a frequency band having an angular frequency higher than the angular frequency ω _C , most of the signal components corresponding to the peak are present. In the − direction, the shift angular frequency is gradually decreased from a sufficiently large shift angular frequency until all of it passes through the filter unit.

<Operation>
The operation of the interference signal removing device 100C configured as described above will be described mainly focusing on the interference signal peak search operation in the interference signal removing device 100C, which is different from the operation of the interference signal removing device 100A. To do.

First, the control unit 130C notifies the local oscillation unit 210 that the shift angular frequency ω _SH is a sufficiently large angular frequency ω _SH1 by the shift frequency designation SFA, and the shift direction is set to the − direction by the shift direction designation SD1. To the shift calculation unit 220A. As a result, local oscillator 210 generates signals C2 and S2 of angular frequency ω _SH1 and sends them to shift calculator 220A.

On the other hand, as described above, the signals C1 and S1 are sent from the orthogonal signal generation unit 110 to the shift calculation unit 220A. Therefore, the shift calculation unit 220A has an angular frequency ω in the − direction with respect to the signals C1 and S1. _The signal shifted by _SH1 is output as signals C3 and S3 (see FIG. 18A). Then, a signal component in a frequency band corresponding to an angular frequency higher than the angular frequency ω _HP in the signals C3 and S3 is detected by the detection unit 240 via the filter unit 230. As a result, the detection unit 240 detects a signal corresponding to a signal component in a frequency band corresponding to an angular frequency higher than the angular frequency (ω _HP + ω _SH1 ) in the input signal C 0 from the signal source 910. The detection result thus obtained is reported to the control unit 130C.

Thereafter, the control unit 130C maintains the negative direction as the shift direction and gradually decreases the shift angular frequency ω _SH , while the signal component extracted by the filter unit 230 is detected by the detection unit 240, and the control is performed. Reported to section 130C. Based on the change in the detection result obtained in this way, the control unit 130C has a peak of the disturbing signal in the frequency band where the angular frequency is higher than the angular frequency ω _C in the spectrum distribution of the signal C0, and corresponds to the peak. It is determined whether almost all the signal components to be transmitted have passed through the filter unit. Then, as shown in FIG. 18B, when the shift angular frequency ω _SH becomes ω _SH2 and the determination becomes affirmative, the control unit 130C stops changing the shift angular frequency ω _SH .

  While searching for the peak of the interference signal as described above, the interference signal removal device 100C removes the interference signal in the same manner as in the interference signal removal device 100A.

Note that the mode of changing the shift angular frequency ω _SH in consideration of the detection result is not limited to the above, and can be any mode.

  As described above, in this embodiment, as in the first and second embodiments, the in-phase signal C1 of the signal C0 from the signal source 910 and its quadrature signal S1 are frequency-shifted and then fixed. The presence or absence of an interference signal is detected by extracting and detecting the frequency band with a fixed filter. Then, based on the detection result of the presence / absence of the interfering signal, either the pair of the signals C1 and S1 or the pair of the signals C6 and S6 from which the signal component in the fixed frequency band is removed is removed from the interfering signal. Assume that the output signal of the device 100C. Therefore, the interference signal in the signal C0 from the signal source 910 can be easily removed.

Further, the control unit 130C automatically changes the shift angular frequency ω _SH in consideration of the detection result in the detection unit 240. For this reason, the signal component of the frequency band in which the interference signal in the signal C0 from the signal source 910 exists can be automatically specified.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference mainly to FIGS.

<Configuration>
As shown in FIG. 19, the interference signal canceling apparatus 100D of this embodiment includes a quadrature signal generating unit 110, a signal detection unit 120A _1, a signal selecting unit 140 _1, a signal detector 120A _2, second signal a signal selector 140 ₂ as a selection means, and a control section 130D of the control means (claim 6). Here, the signal selection unit 140 ₁ and the signal selection unit 140 ₂ are configured in exactly the same way as the signal detection unit 140 in the first and third embodiments described above.

The signal detection unit 120A ₁ is configured in exactly the same way as the signal detection unit 120A in the first and third embodiments described above. Further, the signal detection unit 120A ₂ is different from the signal detection unit 120A ₁ only in that the characteristics of the filter unit are different. In the following description, the component “1” is attached to the component and the internal signal of the signal detector 120A ₁ , and the suffix “2” is attached to the component and the internal signal of the signal detector 120A _2. To do.
That is, the signal detecting unit 120A ₁ includes a local oscillator 210 _1, the shift calculation unit 220A _1, includes a filter unit 230 _1, a detection unit 240 _1, and a reverse shift calculation unit 250A _1. Here, the local oscillation unit 210 ₁ and the shift calculation unit 220A ₁ constitute a first frequency shift means. The filter unit 230 ₁ and the detection unit 240 ₁ constitute a first signal detection unit. The local oscillating unit 210 ₁ and the inverse shift calculating unit 250A ₁ constitute a first inverse frequency shift means.
The signal detecting unit 120A ₂ includes a local oscillator 210 _2, the shift calculation unit 220A _2, includes a filter unit 230 _2, a detection unit 240 _2, and a reverse shift calculation unit 250A _2. Here, the local oscillation unit 210 ₂ and the shift calculation unit 220A ₂ constitute second frequency shift means. The filter unit 230 ₂ and the detection unit 240 ₂ constitute second signal detection means. The local oscillation unit 210 ₂ and the inverse shift calculation unit 250A ₂ constitute a second inverse frequency shift means.

In this embodiment, the filter 231 _2, 232 ₂ in the filter section 230 _{and second} signal detector 120A ₂ is configured to employ a high-pass filter having a transmission characteristic (cutoff angular frequency = omega _LP) as shown in FIG. 20 As the filters 233 ₂ and 234 ₂ , low-pass filters having transmission characteristics (cut-off angular frequency = ω _LP ) as shown in FIG. 21 are employed.

Returning to Figure 19, the signal detecting unit 120A _2, under the control of the control unit 130D, to the signal C7, S7 output from the signal selector 140 _1, the signal detection unit 120A for the signal C1, S1 Processing similar to the processing performed in ₁ (that is, processing performed in the above-described signal detection unit 120A) is performed. As a result of this process, the signal detecting unit 120A ₂ the signal C8 (8-phase signal (claim 6)), S8 together (eighth quadrature signal (claim 6)) is output to the signal selection section 140 ₂ The detection results of the detection unit 240 ₂ are output as signals D1 ₂ and D2 ₂ to the control unit 130D.

Signal selector 140 _2, under the control of the control unit 130D, and selects one of the pairs of pairs and signals of the signal C7, S7 C8, S8, and outputs a signal C9, S9. The signals C9 and S9 are output from the output terminals 150 ₁ and 150 ₂ to the outside of the apparatus.

Similar to the control unit 130A in the first embodiment, the control unit 130D includes a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), peripheral circuits, and the like. This control unit 130D shifts the shift angular frequency ω _SH corresponding to the amount of frequency shift related to the signals C1 and S1 in accordance with the designation of the frequency band of the signal to be detected whether there is an interference signal input to the operation input device. The frequency designation SFA ₁ is sent to the local oscillator 210 ₁ in the signal detector 120A ₁ . Further, the control unit 130D sends the shift angular frequency ω _SL corresponding to the amount of frequency shift related to the signals C7 and S7 to the local oscillation unit 210 ₂ in the signal detection unit 120A ₂ as the shift frequency designation SFA ₂ .

Control unit 130D sends the shift directions as shift direction designations SD1 ₁ and SD2 ₁ to shift calculation unit 220A ₁ and reverse shift calculation unit 250A ₁ in signal detection unit 120A ₁ . Also, the control unit 130D sends the shift directions as shift direction designations SD1 ₂ and SD2 ₂ to the shift calculation unit 220A ₂ and the reverse shift calculation unit 250A ₂ in the signal detection unit 120A ₂ .

Control unit 130D the detection result D1 _1, D2 ₁ from the detection unit 240 ₁ in the signal detecting unit 120A _1, and receives the detection result D1 _2, D2 ₂ from detector 240 ₂ in the signal detecting unit 120A _2. Then, the control unit 130D determines the presence / absence of an interfering signal based on the detection results D1 ₁ , D2 ₁ , D1 ₂ , D2 ₂ , and determines the signal selection unit 140 ₁ based on the determination result. A signal to be selectively output is designated by the signal selection control signal SLT _{1 and} a signal to be selectively outputted by the signal selection control signal SLT ₂ is designated to the signal selection unit 140 ₂ .

<Operation>
In the interference signal removing device 100D configured as described above, the interference signal is removed as follows. In the following description, the signal C0 from the signal source 910 includes the interference signal NZH on the high frequency side in addition to the desired signal SG as shown in FIG. In the case where the interference signal NZL is present, the following description will be given mainly.

First, the control unit 130D sends the shift angular frequency ω _SH and the shift direction to the signal detection unit 120A ₁ as the shift frequency designation SFA ₁ and the shift direction designations SD1 ₁ and SD2 ₁ according to the frequency band designation from the operation input device. The shift angular frequency ω _SL and the shift direction are sent to the signal detection unit 120A ₂ as a shift frequency designation SFA ₂ and shift direction designations SD1 ₂ and SD2 ₂ .

As a result, the signal detection unit 120A ₁ performs the same processing as that of the signal detection unit 120A of the first embodiment described above. That is, the shift calculation unit 220A _1, with respect to the signal C1, S1, shift direction designated SD1 ₁ only frequency shift angular frequency omega _SH in the shift direction designated by the signal C3 ₁ (second phase signal), S3 ₁ ( (Second orthogonal signal) is generated (see FIG. 22B). The signals C3 ₁ and S3 ₁ generated in this way are, in the filter unit 230 ₁ , signals C5 ₁ and S5 ₁ (see FIG. 22C) having an angular frequency larger than the angular frequency ω _HP toward the detection unit 240 ₁ . Are separated into signals C4 ₁ (third in-phase signal) and S4 ₁ (third orthogonal signal) (see FIG. 23A ) having an angular frequency equal to or lower than the angular frequency ω _HP toward the reverse shift calculation unit 250A ₁ . The Then, the signals C4 ₁ and S4 ₁ are subjected to a frequency shift opposite to the frequency shift performed by the shift calculation unit 220A ₁ in the reverse shift calculation unit 250A ₁ , thereby generating signals C6 and S6. (See FIG. 23B).

On the other hand, the signal C5 _1, S5 ₁ is detected is received by the detection unit 240 _1. The detection results in the detection unit 240 ₁ are sent to the control unit 130D as signals D1 ₁ and D2 ₁ . In addition to the signals D1 ₁ and D2 ₁ , the control unit 130D further considers later-described signals D1 ₂ and D2 ₂ sent from the signal detection unit 120A _2, and includes interference signals in the signals C5 ₁ and S5 _1. It is determined whether or not.

Results of the determination of the presence or absence of interference signal in the signal C5 _1, S5 _1, as shown in the above FIG. 22 (C), when the signal C5 _1, S5 ₁ is determined to contain a disturbing signal The control unit 130D designates that the signals C6 and S6 should be selectively output to the signal selection unit 140 ₁ by the signal selection control signal SLT ₁ . On the other hand, when the signal C5 _1, S5 ₁ is determined not to contain interfering signals, the control unit 130D, to the signal selector 140 _1, that should be selected output signals C1, S1, It is designated by the signal selection control signal SLT ₁ . Incidentally, in FIG. 23 (B) ~ Figure 24 (C), the signal C5 _1, S5 ₁ to be determined to contain a disturbing signal, the signal C6, S6 is a signal C7, S7 from the signal selector 140 ₁ As shown in FIG.

Thus signal C7, S7 output from the signal selector 140 _1, the shift calculation unit 220A _2, with respect to the signal C7, S7, is only frequency-shifted angular frequency omega _SL in the shift direction designated by the shift direction designation SD1 ₂ Signals C3 ₂ (sixth in-phase signal) and S3 ₂ (sixth quadrature signal) are generated (see FIG. 23C). Incidentally, in FIG. 23 (C), the examples of which are illustrated in the case shift direction designated by the shift direction designation SD1 ₂ was + direction.

Subsequently, the signal C3 _2, S3 _2, in the filter unit 230 _2, a signal C5 _2, S5 ₂ having a small angular frequency than the angular frequency omega _LP toward the detector 240 ₂ (see FIG. 24 (A)), the reverse The signals are separated into signals C4 ₂ (seventh in-phase signal) and S4 ₂ (seventh in-phase signal) (see FIG. 24B) having an angular frequency equal to or higher than the angular frequency ω _LP toward the shift calculation unit 250A ₂ . . Then, the signals C4 ₂ and S4 ₂ are subjected to frequency shift opposite to the frequency shift performed in the shift calculation unit 220A ₂ in the reverse shift calculation unit 250A ₂ to generate signals C8 and S8. (See FIG. 24C).

On the other hand, the signals C5 ₂ and S5 ₂ are received and detected by the detector 240 ₂ . As described above, the detection results in the detection unit 240 ₂ are sent to the control unit 130D as signals D1 ₂ and D2 ₂ . Based on the signals D1 ₁ , D2 ₁ , D1 ₂ , and D2 ₂ , the control unit 130D determines whether or not an interference signal is included in the signals C5 ₁ and S5 ₁ , and at the same time, the signals C5 ₂ and S5 _2. It is determined whether or not a jamming signal is included. Such a determination is made, for example, considering whether at least one of the signals D1 ₂ and D2 ₂ is equal to or greater than a predetermined value, the relationship between the signals D1 ₁ and D2 ₁ and the signals D1 ₂ and D2 _2, and the like. Incidentally, the determination of whether or not contain interference signal to the signal C5 _1, S5 ₁ described above also, for example, whether at least one of the signals D1 _1, D2 ₁ is the predetermined value or more, the signal D1 _1, This is performed in consideration of the relationship between D2 ₁ and the signals D1 ₂ and D2 ₂ .

Results of the determination of the presence or absence of interference signal in the signal C5 _2, S5 _2, when the signal C5 _2, S5 ₂ is determined to contain a disturbing signal, the control unit 130D to the signal selection section 140 ₂ On the other hand, the signal selection control signal SLT ₂ designates that the signals C8 and S8 should be selectively output. As a result, after the signals C8 and S8 are selected from the signal selector 140 ₂ , they are output from the output terminals 150 ₁ and 150 ₂ as the output signals C9 and S9.

On the other hand, the result of the determination of the presence or absence of the interference signal, when the signal C5 _2, S5 ₂ is determined not to contain interfering signals, the control unit 130D, to the signal selector 140 _2, signal C7 , S7 should be selected and output by the signal selection control signal SLT ₂ . As a result, after the signals C7 and S7 are selected from the signal selector 140 ₂ , they are output from the output terminals 150 ₁ and 150 ₂ as the output signals C9 and S9.

  As described above, in the present embodiment, as in the first to third embodiments, the in-phase signal C1 of the signal C0 from the signal source 910 and the quadrature signal S1 thereof are frequency-shifted and then fixed. The presence or absence of an interference signal is detected by extracting and detecting the frequency band with a fixed filter. Then, a signal to be output is selected based on the detection result of the presence or absence of the interference signal. Therefore, the interference signal in the signal C0 from the signal source 910 can be easily removed.

Further, since the interference signal is removed in series for the two frequency bands by the two signal detection units 120A ₁ and 120A ₂ , signals of two desired different frequency bands in the signal C0 from the signal source 910 are used. Components can be removed simultaneously. For example, it is possible to accurately remove adjacent interference signals derived from broadcast waves from adjacent stations around the broadcast wave from the desired station.

[Modification of Embodiment]
The present invention is not limited to the first to fourth embodiments described above, and various modifications can be made.

For example, in the first to fourth embodiments described above, the signal C0 of the signal source 910 is expressed by the above equation (1), but is expressed by the following more general equation (22): Even so, the signal component in the desired frequency band can be detected as in the case of the first to fourth embodiments.
C0 (t) = F1 · cos (ω ₁ · t + φ ₁ ) + F2 · cos (ω ₂ · t + φ ₂ ) +.
... (22)

  In this case, the quadrature signal generation unit 110 may include a 90 ° phase shifter or a Hilbert transformer, and generate the in-phase signal C1 of the signal C0 and the quadrature signal S1 of the signal C1.

  In the first to fourth embodiments, the quadrature signal generation unit 110 does not change the frequency band when generating the in-phase signal C1 and the quadrature signal S1 from the signal C0. On the other hand, when generating the in-phase signal C1 and the quadrature signal S1 from the signal C0, the in-phase signal C1 and the quadrature signal S1 can be generated while shifting the frequency band of the signal C0. . In this case, for example, when the signal C0 is expressed by the above equation (1), the center frequency of the signal C0 and the center frequencies of the signals C1 and C2 are different from each other. Information on F (t) in the equation is maintained as it is in the signals C1 and C2.

  In the first to fourth embodiments, the in-phase signal C1 and the quadrature signal S1 of the signal C0 are generated from the signal C0 of the signal source 910. However, the in-phase signal and the quadrature signal thereof are generated from the signal source. Is output, the orthogonal signal generator 110 can be omitted.

  In addition, the transmission characteristics of the filter unit in the first to fourth embodiments described above are examples, and can be set as other transmission characteristics.

  Further, the modification of the first embodiment to the second embodiment, that is, the adoption of designation of a signed shift frequency can be applied to the third and fourth embodiments.

  Further, the modification of the first embodiment to the third embodiment, that is, the adoption of the automatic change of the shift frequency amount considering the detection result can be applied to the second and fourth embodiments.

The above-described in the fourth embodiment, disposing the signal detector 120A ₁ and the signal detecting unit 120A ₂ in series, as interference signal canceling apparatus 100E shown in FIG. 25, the signal detection unit 120A ₁ and the signal The detectors 120A ₂ can also be arranged in parallel. In this interference signal removing apparatus 100E, the control means control section 130E as (Claim 7), the signal D1 ₂ from the signal D1 _1, D2 ₁ and the signal detecting unit 120A ₂ from the signal detection unit 120A _1, D2 ₂ to the first signal selecting means and controls the signal selector 145 as (claim 7) on the basis of the quadrature signal generating unit 110 signal C1 which is generated by, S1, signals generated by the signal detecting unit 120A ₁ C6 , S6, and, the signal generated by the signal detecting unit 120A ₂ C10 (8-phase signal (claim 7)), S10 (eighth quadrature signal (claim 7)) to output one of It has become. According to the interference signal canceling apparatus 100E, the signal C0 from the signal source 910, if there is a disturbing signal on any of the two specific frequency range, it is possible to remove the interfering signal.

  In the first to fourth embodiments described above, the signal detection unit 120A (120B) has the inverse shift calculation unit 250A (250B). However, for example, the frequency changes relative to an FM modulation signal. When the information is in the form of a compound, the reverse shift calculation unit 250A (250B) can be omitted.

In the first to fourth embodiments, the signal S1 obtained by quadrature modulation of the signal C0 of the signal source 910 is the signal expressed by the above equation (3), but is expressed by the following equation (23). Even in this case, the signal component in the desired frequency band is detected by changing the multiplication or addition / subtraction in the shift calculation unit 220A (220B) as in the case of the first to fourth embodiments. Can do.
S1 (t) = F (t) · (−sin (ω _C · t + φ)) (23)

In the first to third embodiments, one signal detector 120A (120B) is provided. In the fourth embodiment, two signal detectors 120A ₁ and 120A ₂ are provided. Provide at least three signal detection units equivalent to the unit 120A (120B) and arrange them in series or in parallel according to the nature of the interference signal to be removed to constitute the interference signal removal device. May be.

  The functions of the orthogonal signal generation unit, the signal detection unit, and the signal selection unit in the first to fourth embodiments are the same as those in a DSP (Digital Signal Processor) when the signal C0 is output from the signal source 910 in a digital format. It can also be realized by executing a program. In such a case, the function of the local oscillating unit 210 can generate the C2 and S2 signals by referring to the sin and cos tables according to the designation of the phase or angular frequency. Such a program may be acquired in a form recorded in a portable recording medium such as a CD-ROM or DVD, or may be acquired in a form of delivery via a network such as the Internet. Also good.

It is a block diagram which shows the schematic structure of the interference signal removal apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure of the orthogonal signal part in the apparatus of FIG. It is a block diagram which shows the structure of the signal detection part in the apparatus of FIG. It is a block diagram which shows the structure of the local oscillation part in FIG. It is a block diagram which shows the structure of the shift calculation part in FIG. It is a block diagram which shows the structure of the filter part in FIG. FIG. 7 is a diagram (No. 1) for describing an example of filter characteristics in FIG. 6; FIG. 7 is a diagram (No. 2) for explaining an example of filter characteristics in FIG. 6; It is a block diagram which shows the structure of the detection part in FIG. It is a block diagram which shows the structure of the reverse shift calculation part in FIG. FIG. 3 is a diagram (part 1) for explaining an interference signal removal operation by the apparatus of FIG. 1; FIG. 6 is a diagram (part 2) for explaining the interference signal removal operation by the apparatus of FIG. 1; It is a block diagram which shows schematic structure of the interference signal removal apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the structure of the signal detection part in the apparatus of FIG. It is a block diagram which shows the structure of the shift calculation part in FIG. It is a block diagram which shows the structure of the reverse shift calculation part in FIG. It is a block diagram which shows schematic structure of the interference signal removal apparatus which concerns on 3rd Embodiment of this invention. It is a figure for demonstrating the interference signal search operation | movement by the apparatus of FIG. It is a block diagram which shows schematic structure of the interference signal removal apparatus which concerns on 4th Embodiment of this invention. FIG. 20 is a diagram (No. 1) for describing an example of filter characteristics in FIG. 19; FIG. 20 is a diagram (No. 2) for describing an example of the characteristic of the filter in FIG. 19; It is FIG. (1) for demonstrating the removal operation | movement of the interference signal by the apparatus of FIG. FIG. 20 is a diagram (part 2) for explaining the interference signal removal operation by the apparatus of FIG. 19; FIG. 20 is a diagram (No. 3) for explaining the interference signal removal operation by the apparatus of FIG. 19; It is a block diagram which shows schematic structure of the interference signal removal apparatus of a modification.

Explanation of symbols

100A to 100E ... Interference signal removing device 110 ... Orthogonal signal generator (signal generator)
130A-130E ... Control part (control means)
140, 145 ... Signal selection unit (signal selection means)
210 ... Local oscillator (one of frequency shift means and reverse frequency shift means
Part)
220A: Shift calculation unit (part of frequency shift means)
230 ... Filter unit (part of signal detection means)
240... Detection unit (part of signal detection means)
250A: Inverse shift calculation unit (part of reverse frequency shift means)

Claims (13)

A frequency component of the first in-phase signal based on a first shift frequency and a first shift direction that is a shift amount of a frequency related to the first in-phase signal and a first quadrature signal that is a quadrature signal of the first in-phase signal. The frequency component of the second in-phase signal that is shifted by the first shift frequency in the first shift direction and the frequency component of the first quadrature signal are shifted by the first shift frequency in the first shift direction. First frequency shift means for generating a generated second orthogonal signal;
First signal detection means for detecting a signal component in a predetermined first frequency range included in the second in-phase signal and the second quadrature signal;
A pair of the first in-phase signal and the first quadrature signal, and a third in-phase signal and a third quadrature signal obtained by removing signal components in the first frequency range from the second in-phase signal and the second quadrature signal. First signal selection means for selectively outputting any one of a pair of a fourth in-phase signal and a fourth quadrature signal corresponding to as a fifth in-phase signal and a fifth quadrature signal;
Based on the detection means by the first signal detection means, performs a first determination that is a determination of the presence or absence of an interfering signal in the first frequency range of at least one of the second in-phase signal and the second quadrature signal, If the result of the first determination is affirmative, the first signal selection means is instructed to select the output of the fourth in-phase signal and the fourth quadrature signal pair, and the first determination A control means for instructing the first signal selection means to output a selection output of the pair of the first in-phase signal and the first quadrature signal ,
The control means includes
Collecting the detection results by the first signal detecting means while changing the frequency shift frequency of the frequency component of the signal input to the first frequency shifting means;
Based on the collected detection results, specify a frequency distribution range of the jamming signal,
Determining the first shift frequency and the first shift direction based on the specified frequency distribution range of the interference signal;
An interference signal removing apparatus characterized by the above.   The interference signal removing apparatus according to claim 1, wherein the fourth in-phase signal and the fourth quadrature signal are the third in-phase signal and the third quadrature signal itself.   The fourth in-phase signal is generated by shifting the frequency of the frequency component of the third in-phase signal by the first shift frequency in the opposite direction of the first shift direction, and the frequency component of the third quadrature signal The interference signal according to claim 1, further comprising first inverse frequency shift means for generating the four orthogonal signals by shifting the frequency by the first shift frequency in a direction opposite to the first shift direction. Removal device.   4. The interference signal removal according to claim 1, wherein the control unit designates the first shift frequency and the first shift direction with respect to the first frequency shift unit. 5. apparatus. Based on the second shift frequency and the second shift direction, which are frequency shift amounts related to the fifth in-phase signal and the fifth quadrature signal, the frequency of the frequency component of the fifth in-phase signal is changed in the second shift direction. A sixth in-phase signal shifted by the second shift frequency and a sixth quadrature signal in which the frequency component of the fifth quadrature signal is shifted in the second shift direction by the second shift frequency are generated. Second frequency shift means;
Second signal detection means for detecting a signal component in a predetermined second frequency range included in the sixth in-phase signal and the sixth quadrature signal;
A pair of the fifth in-phase signal and the fifth quadrature signal, and a seventh in-phase signal and a seventh quadrature signal obtained by removing signal components in the second frequency range from the sixth in-phase signal and the sixth quadrature signal. And second signal selection means for selectively outputting any one of a pair of an eighth in-phase signal and an eighth quadrature signal corresponding to
The control means considers the detection result by the second signal detection means in addition to the detection result by the first signal detection means, and takes the second in-phase signal and / or the second quadrature signal into the first signal. Based on the result of the second determination, a second determination that is a determination of the presence or absence of an interfering signal in one frequency range and at least one of the sixth in-phase signal and the sixth quadrature signal in the second frequency range is performed. The interference signal removing apparatus according to claim 1, wherein a selection output command is issued to the first signal selection unit and the second signal selection unit. Based on a second shift frequency and a second shift direction, which are frequency shift amounts related to the first in-phase signal and the first quadrature signal, the frequency component of the first in-phase signal has a frequency in the second shift direction. A sixth in-phase signal shifted by the second shift frequency and a sixth quadrature signal in which the frequency component of the first quadrature signal is shifted in the second shift direction by the second shift frequency are generated. Second frequency shift means;
A second signal detecting means for detecting a signal component in a predetermined second frequency range included in the sixth in-phase signal and the sixth quadrature signal;
The first signal selecting means includes the first in-phase signal and the first quadrature signal pair, the fifth in-phase signal and the fifth quadrature signal pair, the sixth in-phase signal and the first in-phase signal. Any of three signal pairs including a seventh in-phase signal obtained by removing signal components in the second frequency range from six quadrature signals and a pair of eighth in-phase signal and eighth quadrature signal corresponding to the seventh quadrature signal. Selectively output one signal pair,
The control means considers the detection result by the second signal detection means in addition to the detection result by the first signal detection means, and takes the second in-phase signal and / or the second quadrature signal into the first signal. Based on the result of the second determination, a second determination that is a determination of the presence or absence of an interfering signal in one frequency range and at least one of the sixth in-phase signal and the sixth quadrature signal in the second frequency range is performed. The interference signal removal apparatus according to claim 1, wherein a selection output command is issued to the first signal selection unit. The interference signal removing apparatus according to claim 5 or 6 , wherein the eighth in-phase signal and the eighth quadrature signal are the seventh in-phase signal and the seventh quadrature signal itself. The eighth in-phase signal is generated by shifting the frequency component of the seventh in-phase signal by the second shift frequency in the direction opposite to the second shift direction, and the frequency component of the seventh quadrature signal 7. The apparatus according to claim 5 , further comprising second inverse frequency shift means for generating the 8-orthogonal signal by shifting the frequency in the direction opposite to the second shift direction by the second shift frequency. Interference signal removal device. 9. The interference signal removal according to claim 5 , wherein the control means designates the second shift frequency and the second shift direction with respect to the second frequency shift means. apparatus. The control means includes
Collecting the detection results by the second signal detection means while changing the frequency shift frequency of the frequency component of the signal input to the second frequency shift means;
Based on the collected detection results, specify a frequency distribution range of the jamming signal,
Determining the second shift frequency and the second shift direction based on the specified frequency distribution range of the disturbing signal;
The interference signal removing device according to claim 9 . The interference signal removal according to any one of claims 1 to 10 , further comprising signal generation means for generating the first in-phase signal and the first quadrature signal from an external input signal. apparatus. Said signal generating means generates the first phase signal as an in-phase signal of said input signal, to generate the first orthogonal signal as an orthogonal signal of the input signal, that to claim 11, wherein The interference signal removing device as described. Based on a shift frequency and a shift direction, which is a frequency shift amount related to a first quadrature signal that is a quadrature signal of the first in-phase signal and the first in-phase signal, the frequency of the frequency component of the first in-phase signal is Frequency shift means for generating a second in-phase signal shifted in the shift direction by the shift frequency and a second quadrature signal in which the frequency component of the first quadrature signal is shifted in the shift direction by the shift frequency. And a signal detection means for detecting a signal component in a predetermined frequency range included in the second in-phase signal and the second quadrature signal. And
The detection result by the signal detection means is collected while changing the frequency shift frequency of the frequency component of the signal input to the frequency shift means, and based on the collected detection result, the frequency distribution range of the interference signal is obtained. Determining and determining the shift frequency and the shift direction based on a frequency distribution range of the identified jamming signal;
Based on the detection result by the signal detection means, it is determined whether or not there is an interfering signal in the frequency range of at least one of the second in-phase signal and the second quadrature signal, and the determination result is positive. A pair of fourth in-phase signal and fourth quadrature signal corresponding to the third in-phase signal and the third quadrature signal obtained by removing the signal component in the frequency range from the second in-phase signal and the second quadrature signal. A first signal selection step of performing a selective output of;
And a second signal selection step of selecting and outputting a pair of the first in-phase signal and the first quadrature signal when the result of the determination is negative. .

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