JP4950106B2 - Frequency generating device, frequency generating method, signal processing device, and signal processing method - Google Patents

Description

  The present invention relates to a frequency generation device, a frequency generation method, a frequency generation program, a recording medium on which the frequency generation program is recorded, a signal processing device, a signal processing method, a signal processing program, and the signal processing program. The present invention relates to a recorded recording medium.

  2. Description of the Related Art Conventionally, FM receivers that receive and process FM broadcast waves that are signals obtained by FM (Frequency Modulation) modulation of a signal including a predetermined signal such as a pilot signal serving as a reference for demodulation processing have been widely used. ing. In such an apparatus, in order to reproduce the predetermined signal or generate a signal having a frequency that is an integral multiple of the frequency of the predetermined signal, a phase locked loop (PLL) technique is generally employed ( Patent Document 1; hereinafter referred to as “Conventional Example 1”).

  Apart from the technique of Conventional Example 1, a technique for reproducing the predetermined signal or generating a signal having a frequency that is an integral multiple of the frequency of the predetermined signal without adopting the PLL technique has been proposed. (See Patent Document 2; hereinafter referred to as “Conventional Example 2”). In the conventional technique, a phase difference between a base signal generated internally and the predetermined signal is obtained. Then, the predetermined signal is reproduced by adding the obtained phase difference to the base signal.

JP 2000-13339 A JP 2006-528451 Gazette

  Although the technique of the conventional example 1 employs the PLL technique, the PLL is generally difficult to design. Further, when the PLL method is used, it is difficult to synchronize with the predetermined signal with good follow-up in a situation where the reception environment changes as in the case of mobile reception of FM broadcast waves, for example. .

  Further, in the technique of Conventional Example 2 described above, a reference signal for matching the phase of the predetermined signal is necessary. However, when the frequency and phase of the predetermined signal fluctuate due to the occurrence of multipath, it is not always easy to generate a reference signal for synchronizing with the predetermined signal with high accuracy.

  Furthermore, in order to generate a signal obtained by reproducing the predetermined signal or a signal synchronized with the predetermined signal (hereinafter also referred to as a “reference signal”), a frequency corresponding to the predetermined signal or the signal corresponding to the predetermined signal is used as a key. However, a filter is used for such extraction. Here, the filter generally has different characteristics of phase shift and amplitude change depending on the frequency of the signal passing therethrough. For this reason, in order to generate a desired reference signal with high accuracy, it is necessary to consider the characteristics of the filter. For example, if the characteristics of the amplitude change cannot be specified with high accuracy, the pilot signal cancellation processing in the FM signal cannot be performed with high accuracy.

  For this reason, there is a need for a new technique that can process an input signal with high accuracy while easily and quickly synchronizing with a predetermined signal with high accuracy. Meeting this requirement is one of the problems to be solved by the present invention.

  The present invention has been made in view of the above, and an object of the present invention is to provide a frequency generation device and a frequency generation method that can accurately generate a frequency corresponding to a predetermined signal included in an input signal.

  It is another object of the present invention to provide a signal processing apparatus and a signal processing method that can accurately synchronize with a predetermined signal included in an input signal and that can accurately correct the input signal.

The invention according to claim 1 is a frequency generation device that generates a frequency corresponding to a predetermined signal included in an input signal, and performs a process of orthogonalizing at least the predetermined signal, and a component corresponding to the predetermined signal Orthogonalizing means for generating a first orthogonalized signal and a second orthogonalized signal that are orthogonal to each other; a first signal that is included in the first orthogonalized signal and has a phase reflecting the phase of the predetermined signal; and Filter means for selectively passing a second signal orthogonal to the first signal included in the second orthogonal signal; a signal reflecting the predetermined signal based on the first signal and the second signal A phase calculating unit that calculates a phase of the signal, and a generating unit that generates a frequency corresponding to the predetermined signal based on a calculation result by the phase calculating unit , wherein the orthogonalizing unit includes, in addition to the orthogonalizing, , The frequency shift in accordance with the wave number shift setting, it is the frequency generating device according to claim.

Invention of Claim 4 is the frequency generator as described in any one of Claims 1-3 ;
Correction means for correcting, as a correction target signal, a phase information signal output from the phase calculation means or at least one of the first signal and the second signal based on the frequency generated by the frequency generation device; A signal processing apparatus comprising:

The invention according to claim 15 is a frequency generation method for generating a frequency corresponding to a predetermined signal included in an input signal, wherein at least the predetermined signal is subjected to orthogonalization processing, and a component corresponding to the predetermined signal An orthogonalization step of generating a first orthogonalized signal and a second orthogonalized signal that are orthogonal to each other; a first signal that is included in the first orthogonalized signal and has a phase reflecting the phase of the predetermined signal; and A filtering step of selectively passing a second signal that is included in the second orthogonal signal and orthogonal to the first signal; and a signal that reflects the predetermined signal based on the first signal and the second signal a phase calculating step of calculating a phase of; based on the calculation result in the phase calculating step, a generation step of generating a frequency corresponding to the predetermined signal; equipped with, in the orthogonalization process, before In addition to the orthogonalization, the frequency shift in accordance with the frequency shift setting is performed, frequency generation method, characterized in that. It is.

According to a sixteenth aspect of the present invention, there is provided a frequency generation step of generating a frequency corresponding to a predetermined signal by the frequency generation method according to the fifteenth aspect ; and the phase calculation based on the frequency generated in the frequency generation step. And a correction step of correcting at least one of the phase information signal generated in the step or the first signal and the second signal as a correction target signal .

The invention according to claim 17 is a frequency generation program characterized by causing a calculation means to execute the frequency generation method according to claim 15 .

According to an eighteenth aspect of the present invention, there is provided a signal processing program that causes a calculation means to execute the signal processing method according to the sixteenth aspect.

A nineteenth aspect of the invention is a recording medium in which the frequency generation program according to the seventeenth aspect is recorded so as to be readable by an arithmetic means.

A twentieth aspect of the invention is a recording medium in which the signal processing program according to the eighteenth aspect of the invention is recorded so as to be readable by an arithmetic means.

  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 a signal processing device 100A according to the first embodiment. The signal processing device 100A is a device that receives and processes the signal SIA output from the signal source 910 via the input terminal 191 and outputs the signal SIA as the reference signal BSA from the output terminal 192.

In the first embodiment, the signal SIA is assumed to include a pilot signal PS having an angular frequency ω _c as shown in FIG. Here, it is assumed that the angular frequency ω _C of the pilot signal PS is slightly changed but may vary with time from the standard angular frequency ω _C0 .

In the first embodiment, in order to simplify the description, it is assumed that the pilot signal PS included in the signal SIA is expressed by the following equation (1).
PS (t) ∝sin [θ _C (t)] = sin (ω _C t + φ ₀ ) (1)
Here, the value φ ₀ is the phase of pilot signal PS when time t = 0.

Note that when the signal processing device 100A is mounted on a moving body such as a vehicle, the angular frequency ω _C and the initial phase value φ ₀ change slightly.

  Examples of the signal represented by the equation (1) include a pilot signal in a composite signal that is a signal obtained by FM detection of an FM broadcast wave.

  Returning to FIG. 1, the signal processing device 100A includes a frequency generation device 180A and a phase correction unit 140 as correction means. Further, the signal processing device 100A includes a reference signal generation unit 150. Here, the frequency generation device 180A includes an orthogonal signal generation unit 110A, a phase calculation unit 120A as a phase calculation unit, and a generation unit 130 as a generation unit.

The orthogonal signal generation unit 110A includes two signals PSA each of which is a signal in a band including the angular frequency ω _C from the signal SIA received via the input terminal 191 and whose components of the angular frequency ω _C are orthogonal to each other. ₁ and PSA ₂ are generated. As shown in FIG. 3, the orthogonal signal generation unit 110A having such a function includes an orthogonalization unit 112A as orthogonalization means and filters (FIL) 113A ₁ and 113A ₂ as filter means.

The orthogonalizing unit 112A is based on the component of the angular frequency ω _C included in the signal SIA (that is, the pilot signal PS) and is orthogonal to each other and two signals OSA reflecting the phase θ _C (t) of the pilot signal PS ₁ and OSA ₂ are generated. Orthogonalization section 112A having such a function, as shown in FIG. 4, and a 90 ° phase shifter 119 for the signal of the angular frequency omega _C.

In the orthogonalizing unit 112A configured as described above, a signal in phase with the received signal SIA is output to the FIL 113A ₁ as the signal OSA ₁ . On the other hand, in the orthogonalizing unit 112A, the phase of the received signal SIA is shifted by 90 ° with respect to the component of the angular frequency ω _C , and is output to the FIL 113A ₂ as the signal OSA ₂ .

Returning to FIG. 3, the FIL 113A ₁ is configured as a digital filter such as an infinite impulse response filter (IIR). The FIL 113A ₁ receives the signal OSA ₁ from the orthogonalizing unit 112A. Then, the FIL 113A ₁ selectively passes a component having an angular frequency in the signal OSA ₁ in the vicinity of the angular frequency ω _C0 , that is, a signal component corresponding to the pilot signal PS, and serves as the signal PSA ₁ toward the phase calculation unit 120A. Output.

Note that a phase shift Δθ associated with the filtering operation may occur through the FIL 113A ₁ . This phase shift Δθ has an angular frequency dependency as shown in FIG. 5, for example. In the first embodiment, it is assumed that such a phase shift Δθ occurs. Here, the angular frequency dependence of the phase shift Δθ by the FIL 113A ₁ is determined by the configuration of the FIL 113A ₁ and is determined at the design stage of the FIL 113A ₁ . In the first embodiment, as shown in FIG. 5, it is assumed that a phase shift Δθ ₀ occurs in the signal having the angular frequency ω _C0 .

In this case, the signal PSA ₁ output from the FIL 113A ₁ is represented by the following equation (2).
PSA ₁ (t) = A (t) · sin [θ _S (t)]
= A (t) · sin [θ _C (t) −Δθ (ω _C )]
= A (t) · sin [(ω _C t + φ ₀ ) −Δθ (ω _C )] (2)
Here, A (t) represents the amplitude value of the pilot signal PS.

Returning to FIG. 3, the FIL 113A ₂ has the same configuration as the FIL 113A ₁ . The FIL 113A ₂ receives the signal OSA ₂ from the orthogonalizing unit 112A. Then, FIL 113A ₂ selectively passes the component of angular frequency ω _C in signal OSA ₂ , that is, the signal component corresponding to pilot signal PS, and outputs signal PSA ₂ .

The signal PSA ₂ output from the FIL 113A ₂ is expressed by the following equation (3).
PSA ₂ (t) = A (t) · cos [θ _S (t)]
= A (t) · cos [θ _C (t) −Δθ (ω _C )]
= A (t) · cos [(ω _C t + φ ₀ ) −Δθ (ω _C )] (3)

Returning to FIG. 1, the phase calculation unit 120A calculates the phase θ _CE (t) of the pilot signal PS based on the signal PSA ₁ and the signal PSA ₂ from the quadrature signal generation unit 110A. At the time of such calculation, the phase calculation unit 120A calculates the phase θ _CE (t) by performing an operation such as arctan on the signal PSA ₁ and the signal PSA ₂ , for example.

The phase θ _CE (t) calculated in this way is output as a signal PHA from the phase calculation unit 120A to the generation unit 130 and the phase correction unit 140.

The generation unit 130 generates a value of the angular frequency ω _C based on the signal PHA from the phase calculation unit 120A. As shown in FIG. 6, the generation unit 130 having such a function includes a frequency calculation unit 131 and a low-pass filter (LPF) 132.

The frequency calculation unit 131 receives the signal PHA from the phase calculation unit 120A. Then, the frequency calculation unit 131 calculates the angular frequency ω _C1 (t) at each time point from the phase difference of the phase θ _CE (t) received as the signal PHA. The angular frequency ω _C1 (t) calculated in this way is output to the LPF 132 as the signal FRC.

The LPF 132 receives the signal FRC from the frequency calculation unit 131. Then, the LPF 132 outputs, as the angular frequency ω _C2 (t), a signal from which unnecessary fluctuation components of the angular frequency at each time point received as the signal FRC are removed. The angular frequency ω _C2 (t) is a final generation result by the generation unit 130.

The angular frequency ω _C2 (t) thus generated is output from the LPF 132 toward the phase correction unit 140 as the signal FRQ. In the following description, the angular frequency ω _C2 (t) is also referred to as “generated angular frequency ω _CE ”.

Returning to FIG. 1, the phase correction unit 140 corrects the phase θ _CE (t) received as the signal PHA from the phase calculation unit 120A using the generated angular frequency ω _CE received as the signal FRQ from the generation unit 130. To do. As shown in FIG. 7, the phase correction unit 140 having such a function includes an addition unit 141 as a phase correction calculation unit and a correction control unit 142.

  The adding unit 141 adds the signal received at the A terminal and the signal received at the B terminal, and outputs the addition result from the C terminal. Here, addition unit 141 receives signal PHA from phase calculation unit 120A at the A terminal and also receives signal MPV from correction control unit 142 at the B terminal. The correction phase signal PHM is output from the C terminal.

  The correction control unit 142 includes a phase correction table 143 as a storage unit. In the phase correction table 143, a correction value δθ (ω) corresponding to the angular frequency ω as shown in FIG. 8 is registered in advance.

Returning to FIG. 7, the correction control unit 142 receives the signal FRQ from the generation unit 130. Then, the correction control unit 142 reads the correction value δθ (ω _CE ) with reference to the phase correction table 143 based on the generated angular frequency ω _CE received as the signal FRQ. The correction value δθ (ω _CE ) read out in this way is regarded as a value δθ (ω _C ), and is output to the adding unit 141 as a signal MPV.

As a result, the adder 141 calculates the following equation (4) and accurately calculates the phase θ _C (t) of the pilot signal PS received at the input terminal 191.
θ _C (t) = θ _CE (t) + δθ (ω _C ) = (ω _C t + φ ₀ ) (4)

The phase θ _C (t) calculated in this way is output from the phase correction unit 140 to the reference signal generation unit 150 as the signal PHM.

Returning to FIG. 1, the reference signal generation unit 150 generates a reference signal BSA having an angular frequency of 2ω _{C in} synchronization with the pilot signal PS based on the signal PHM from the phase correction unit 140. The reference signal generation unit 150 having such a function includes a phase processing unit 151 and a signal generation unit 152, as shown in FIG.

The phase processing unit 151 receives the signal PHM from the phase correction unit 140 and processes the phase θ _C (t) indicated by the signal PHM. In the first embodiment, the phase processing unit 151 calculates the phase θ _M (t) by the following equation (5).
θ _M (t) = 2θ _C (t) = 2 (ω _C t + φ ₀ ) (5)

That is, in the first embodiment, the phase processing unit 151 calculates the phase θ _M (t) that changes at the angular frequency 2ω _C in synchronization with the pilot signal PS. The phase θ _M (t) calculated in this way is output to the signal generator 152 as the phase processing signal MPA.

The signal generator 152 generates the reference signal BSA based on the phase processing signal MPA from the phase processing unit 151. In the first embodiment, the signal generation unit 152 includes a sine value table in which amplitude values corresponding to phase values are registered, and a sine wave signal having a phase θ _M (t) indicated by the phase processing signal MPA. Is generated as a reference signal BSA.

This reference signal BSA is expressed by the following equation (6).
BSA (t) = C ₀ · sin [θ _M (t)]
= C ₀ · sin [2θ _C (t)]
= C ₀ · sin [2 (ω _C t + φ ₀ )] (6)
Here, C ₀ is a constant.

  The reference signal BSA thus generated is output to the outside via the output terminal 192.

<Operation>
Next, a signal processing operation in the signal processing device 100A configured as described above will be described.

When the signal SIA from the signal source 910 is received by the signal processing device 100A via the input terminal 191, the signal SIA is supplied to the orthogonal signal generation unit 110A in the signal processing device 100A (see FIG. 1). In the orthogonal signal generation unit 110A that receives the supply of the signal SIA, first, the orthogonalization unit 112A generates _two signals OSA ₁ and OSA _{2 in} which the components of the angular frequency ω _C included in the signal SIA are orthogonal to each other, and the FIL 113A ₁ , sent to 113A ₂ (see FIG. 4).

Subsequently, FIL113A ₁ which has received the signal OSA ₁ are components of the angular frequency omega _C in the signal OSA _1, i.e., selectively pass a signal component corresponding to the pilot signal PS, for a signal PSA ₁ to phase calculation section 120A Output. The FIL 113A ₂ that has received the signal OSA ₂ selectively allows the component of the angular frequency ω _C in the signal OSA ₂ , that is, the signal component corresponding to the pilot signal PS, to pass to the phase calculation unit 120A as the signal PSA _2. (See FIG. 3).

Here, the signal PSA ₁ has a waveform represented by the above-described equation (2). On the other hand, the signal PSA ₂ has a waveform represented by the above-described equation (3).

The phase calculation unit 120A that has received the signals PSA ₁ and PSA ₂ operates as described above to calculate the phase θ _CE (t) of the pilot signal PS. The phase θ _CE (t) calculated in this way is sent to the generation unit 130 and the phase correction unit 140 as a signal PHA (see FIG. 1).

In the generation unit 130 that receives the signal PHA, the frequency calculation unit 131 calculates the angular frequency ω _C1 (t) at each time point based on the temporal change of the phase θ _CE (t) received as the signal PHA. The angular frequency ω _C1 (t) calculated in this way is sent to the LPF 132 as a signal FRC (see FIG. 6). Receiving the signal FRC, the LPF 132 obtains the angular frequency ω _C2 (t) excluding unnecessary fluctuation components in the signal FRC, that is, the generated angular frequency ω _CE , and sends it to the phase correction unit 140 as the signal FRQ (see FIG. 6).

In the phase correction unit 140 that has received the signal PHA and the signal FRQ, first, the correction control unit 142 refers to the phase correction table 143 based on the generated angular frequency ω _CE received as the signal FRQ, and the correction value δθ (ω _CE ). The correction control unit 142 regards the correction value δθ (ω _CE ) read in this way as the value δθ (ω _C ) at that time, and sends it to the adding unit 141 as a signal MPV (see FIG. 7).

The adder 141 that has received the signal PHA and the signal MPV calculates the phase θ _C (t) of the pilot signal PS by the above-described equation (4). The phase θ _C (t) calculated in this way is sent as a signal PHM from the phase correction unit 140 to the reference signal generation unit 150 (see FIG. 7).

The reference signal generation unit 150 that has received the signal PHM generates a reference signal BSA having an angular frequency of 2ω _{C in} synchronization with the pilot signal PS based on the signal PHM. Upon generation of such a reference signal BSA, the reference signal generator 150, first, a phase processing unit 151, the above-described (5), synchronized with the pilot signal PS, varies at the angular frequency 2 [omega _C phase theta _M (t ) Is calculated and sent to the signal generator 152 (see FIG. 9). Signal generating unit 152 which received the phase theta _M a (t) refers to the internal sine table based on the phase theta _M (t), it is a sine wave signal represented by the above-described (6) reference A signal BSA is generated. The reference signal BSA generated in this way is output to the outside via the output terminal 192 (see FIG. 9).

As described above, in the first embodiment, from the signal SIA in the band including the pilot signal PS of the angular frequency ω _C , without using a feedback loop in the PLL system or a base signal serving as a reference for phase generation. Then, the phase θ _C (t) of the pilot signal PS is derived. Therefore, it is possible to generate the reference signal BSA that is easily and quickly synchronized with the pilot signal PS.

  In the first embodiment, the orthogonal signal generation unit 110A corrects the frequency characteristic of the phase shift that occurs when the pilot signal PS is orthogonalized and extracted based on the angular frequency generated by the generation unit 130. . For this reason, even when the angular frequency of the pilot signal PS varies, it is possible to generate the reference signal BSA that is accurately synchronized with the pilot signal PS.

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

  FIG. 10 is a block diagram illustrating a schematic configuration of a signal processing device 100B according to the second embodiment. The signal processing device 100B receives and processes the signal SIA output from the signal source 910 via the input terminal 191 and processes the reference signal from the output terminal 192, as in the signal processing device 100A in the first embodiment. It is a device that outputs as BSA.

  As illustrated in FIG. 10, the signal processing device 100B includes a frequency generation device 180B instead of the frequency generation device 180A and a filter control unit 145 instead of the phase correction unit 140, as compared with the signal processing device 100A described above. The only difference is that The frequency generation device 180B differs from the frequency generation device 180A described above only in that it includes an orthogonal signal generation unit 110B instead of the orthogonal signal generation unit 110A. Hereinafter, description will be made mainly focusing on these differences.

As shown in FIG. 11, the orthogonal signal generation unit 110B is different from the orthogonal signal generation unit 110A in that FILs 113B ₁ and 113B ₂ are provided instead of the FILs 113A ₁ and 113A ₂ . Here, the FIL113B ₁ and FIL113B _2, have the same configuration.

As shown in FIG. 12, the FIL 113B ₁ and FIL 113B ₂ change the frequency characteristics of the phase shift given to the signal to be passed according to the value of the filter parameter specified by the signal FLC from the filter control unit 145, as shown in FIG. It has become. For this reason, by adjusting the value of the filter parameter designated by the signal FLC, the amount of phase shift can be set to the value Δθ ₀ with respect to the desired angular frequency value.

The signal components that have passed through FIL 113B ₁ and FIL 113B ₂ are output as signals PSB ₁ and PSB ₂ from quadrature signal generation section 110B to phase calculation section 120A.

Returning to FIG. 10, the filter control unit 145 receives the signal FRQ from the generation unit 130. Then, based on the angular frequency ω _CE received as the signal FRQ, the filter control unit 145 sets the value of the filter parameter at which the phase shift amount given by the signals of the angular frequency ω _{CE by} the FIL 113B ₁ and FIL 113B ₂ becomes the value Δθ _0. To decide. The filter parameter value thus determined is output as a signal FLC to the orthogonal signal generation unit 110B (more specifically, FIL113B ₁ and FIL113B ₂ ).

  In the second embodiment, the signal PHM output from the phase calculation unit 120A is directly received by the reference signal generation unit 150.

<Operation>
Next, a signal processing operation in the signal processing device 100B configured as described above will be described.

When the signal SIA from the signal source 910 is received by the signal processing device 100B via the input terminal 191, the signal SIA is supplied to the orthogonal signal generation unit 110B in the signal processing device 100B (see FIG. 10). In the orthogonal signal generation unit 110B that receives the supply of the signal SIA, the orthogonalization unit 112A first generates two signals OSA ₁ and OSA _{2 in} which the components of the angular frequency ω _C included in the signal SIA are orthogonal to each other, and the FIL 113B. ₁ and 113B ₂ (see FIG. 11).

The FILs 113B ₁ and 113B ₂ perform filtering according to the signal FLC from the filter control unit 145 in which a filter parameter is specified such that the phase shift amount given to the signal of the angular frequency ω _CE at the current time point becomes the value Δθ _0. Do. As a result, the FIL113B _1, 113B _2, components in the vicinity of the signal OSA _1, the angular frequency is angular frequency in OSA ₂ omega _C0, i.e., selectively pass a signal component corresponding to the pilot signal PS, the signal PSB ₁ , PSB ₂ are sent to the phase calculation unit 120A (see FIG. 11).

Such signals PSB ₁ and PSB ₂ are expressed by the following equations (7) and (8).
PSB ₁ (t) = A (t) · sin [(ω _C t + φ ₀ ) −Δθ ₀ ] (7)
PSB ₂ (t) = A (t) · cos [(ω _C t + φ ₀ ) −Δθ ₀ ] (8)

The phase calculation unit 120A that has received the signals PSB ₁ and PSB ₂ performs, for example, an arctan operation on the signal PSA ₁ and the signal PSA ₂ to obtain the phase θ _C (t ) Is calculated.

The phase θ _C (t) thus calculated is sent as a signal PHM from the phase calculation unit 120A to the generation unit 130 and the reference signal generation unit 150.

The generation unit 130 that has received the signal PHM obtains the generation angular frequency ω _CE at each time point and sends it to the filter control unit 145 as the signal FRQ in the same manner as in the first embodiment. The filter control unit 145 that has received the signal FRQ, based on the generated angular frequency ω _CE received as the signal FRQ, has the phase shift amount given by the signals FIL 113B ₁ and FIL 113B ₂ as the value of the generated angular frequency ω _{CE as} the value Δθ ₀ . The filter parameter value is determined and sent as a signal FLC to the orthogonal signal generation unit 110B (more specifically, FIL113B ₁ , FIL113B ₂ ).

Due to the action of the control loop formed by the above FIL 113B ₁ , FIL 113B ₂ , phase calculation unit 120A, generation unit 130, and filter control unit 145, the phase calculation unit 120A causes the phase correction unit 140 in the above first embodiment to A value reflecting the phase θ _C (t) of the pilot signal PS is output with the same accuracy as the output signal PHM. In this sense, in the second embodiment, an output signal from the phase calculation unit 120A is denoted as a signal PHM.

The reference signal generation unit 150 that has received the signal PHM generates a reference signal BSA having an angular frequency of 2ω _{C in} synchronization with the pilot signal PS based on the signal PHM in the same manner as in the first embodiment. The reference signal BSA generated in this way is output to the outside via the output terminal 192 (see FIG. 9).

As described above, in the second embodiment, as in the case of the first embodiment described above, the feedback loop and phase generation in the PLL system are generated from the signal SIA in the band including the pilot signal PS of the angular frequency ω _C. The phase θ _C of the pilot signal PS is derived without using the base signal serving as a reference for the above. Therefore, it is possible to generate the reference signal BSA that is easily and quickly synchronized with the pilot signal PS.

Further, in the second embodiment, the frequency characteristics of the phase shift generated when the quadrature signal generation unit 110B orthogonalizes and extracts the pilot signal PS is calculated based on the angular frequency generated by the generation unit 130 as FIL113B ₁ , by controlling the frequency characteristics of the phase shift due to 113B _2, it is corrected. For this reason, even when the angular frequency of the pilot signal PS varies, it is possible to generate the reference signal BSA that is accurately synchronized with the pilot signal PS.

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

  FIG. 13 is a block diagram illustrating a schematic configuration of a signal processing device 100C according to the third embodiment. The signal processing apparatus 100C receives and processes the signal SIA output from the signal source 910 via the input terminal 191 and processes the reference signal from the output terminal 192, as in the signal processing apparatus 100A in the first embodiment. It is a device that outputs as BSA.

  As illustrated in FIG. 13, the signal processing device 100C is different from the above-described signal processing device 100A only in that a frequency generation device 180C is provided instead of the frequency generation device 180A. The frequency generation device 180C includes only an orthogonal signal generation unit 110C instead of the orthogonal signal generation unit 110A and a phase calculation unit 120C instead of the phase calculation unit 120A as compared with the frequency generation device 180A described above. Is different. Hereinafter, description will be made mainly focusing on these differences.

The orthogonal signal generation unit 110C generates two signals PSC ₁ and PSC ₂ that are orthogonal to each other from the signal SIA received via the input terminal 191. As shown in FIG. 14, the orthogonal signal generation unit 110C having such a function includes a band limiting filter 111 as a band limiting unit, an orthogonalizing unit 112C as an orthogonalizing unit, and a filter (FIL) 113C as a filtering unit. ₁ and 113C ₂ .

The band limiting filter 111 is configured as a digital filter such as a finite impulse response (FIR) filter. The band limiting filter 111 selectively passes a signal component of a predetermined frequency band including the angular frequency ω _C in the signal SIA, and outputs the signal component to the orthogonalizing unit 112C as a band limited signal LSI with a limited frequency band.

In the third embodiment, the band limiting filter 111 is configured such that a component folded at a frequency of 0 is obtained as a result of multiplication of a sine wave (∝sin (ω _SH · t)) performed at the time of frequency conversion in the orthogonalizing unit 112C. The frequency band of the signal to be passed is set so as not to overlap (or sufficiently suppressed) as a result of the frequency shift of the signal PS (in the third embodiment, the angular frequency (ω _SH −ω _C ) component). Restrict. In addition, the band limiting filter 111B does not overlap (or sufficiently suppress) the component folded at the half frequency (f _SM / 2) of the sample rate f _SM with the result of the frequency shift of the pilot signal PS. Limit the frequency band of the signal to pass through. The band limiting filter 111 having such a function can be realized, for example, as an FIR low pass filter.

Note that a phase shift may occur due to a filter delay through the band limiting filter 111. In the third embodiment, the following description will be given on the assumption that the phase shift Δθ ₁ due to the filter delay occurs in the band limiting filter 111.

The signal component PS ′ corresponding to the pilot signal PS in the band limited signal LSI output from the band limiting filter 111 configured as described above is expressed by the following equation (9).
PS ′ (t) ∝sin [θ _C (t) −Δθ ₁ (ω _C )]
= Sin [(ω _C t + φ ₀ ) −Δθ ₁ (ω _C )] (9)

Based on the band limited signal LSI, the orthogonalizing unit 112C generates _two signals OSC ₁ and OSC ₂ that are orthogonal to each other and reflect the phase θ _C (t) of the pilot signal PS. In the third embodiment, the orthogonalization unit 112C having such a function includes an oscillation unit 210C and multiplication units 220 ₁ and 220 ₂ as shown in FIG.

The oscillator 210C generates a signal OTS ₁ to be supplied to the multiplier 220 ₁ and a signal OTS ₂ to be supplied to the multiplier 220 ₂ . In the third embodiment, the signal OTS ₁ and the signal OTS ₂ are represented by the following equations (10) and (11).
OTS ₁ (t) = B ₀ · cos (ω _SH · t) (10)
OTS ₂ (t) = B ₀ · sin (ω _SH · t) (11)
Here, B ₀ is a constant.

In the third embodiment, the angular frequency ω _SH is set to a predetermined value larger than 3ω _C. The value of the angular frequency ω _SH is determined from a comprehensive viewpoint together with the band limitation specification by the band limitation filter 111 described above from the viewpoint of preventing the noise component from being mixed into the frequency shift result of the pilot signal PS.

Multiplier 220 ₁ receives band-limited signal LSI at the A terminal and receives signal OTS ₁ from oscillator 210C at the B terminal. Then, a reception result in the A terminal, the multiplication result between the reception result at the B terminal is outputted to the C terminal as signal OSC ₁ to FIL113C _1. Here, pilot signal PS in signal SIA has angular frequency ω _C , and signal OTS ₁ has only a component of angular frequency ω _SH . For this reason, the signal component corresponding to the pilot signal PS in the signal OSC ₁ is frequency-converted into two components of an angular frequency (ω _SH −ω _C ) and an angular frequency (ω _SH + ω _C ).

Multiplier 220 ₂ receives band-limited signal LSI at terminal A and receives signal OTS ₂ from oscillator 210C at terminal B. Then, a reception result in the A terminal, the multiplication result between the reception result at the B terminal is outputted to the C terminal as a signal OSC ₂ to FIL113C _2. Here, pilot signal PS in signal SIA has angular frequency ω _C , and signal OTS ₂ has only a component of angular frequency ω _SH . For this reason, the signal component corresponding to the pilot signal PS in the signal OSC ₂ is divided into _two components of the angular frequency (ω _SH −ω _C ) and the angular frequency (ω _SH + ω _C ) as in the case of the signal OSC _1. Converted.

Returning to FIG. 14, the FIL 113C ₁ is configured as a digital filter such as an infinite impulse response filter (IIR). The FIL 113C ₁ receives the signal OSC ₁ from the orthogonalizing unit 112C. Then, the FIL 113C ₁ selectively passes _one of the signal components corresponding to the pilot signal PS, the component of the angular frequency (ω _SH −ω _C ) in the third embodiment, and the signal PSC ₁ is sent to the phase calculation unit 120C. Output toward.

Note that a phase shift may occur due to filter delay through the FIL 113C ₁ . In the third embodiment, the following description will be given on the assumption that the phase shift Δθ ₂ due to the filter delay in the FIL 113C ₁ occurs.

The signal PSC ₁ output from the FIL 113C ₁ is expressed by the following equation (12).
PSC ₁ (t) = A (t) · sin [θ _S (t)]
= A (t) · sin [ω _SH t−θ _C (t) + Δθ ₁ (ω _C ) −Δθ ₂ (ω _C )]
= A (t) · sin [ω _SH t− (ω _C t + φ ₀ ) + Δθ (ω _C )] (12)
Here, A (t) represents the amplitude value of the pilot signal PS. Further, Δθ (ω _C ) = Δθ ₁ (ω _C ) −Δθ ₂ (ω _C ).

The FIL 113C ₂ is configured in the same manner as the FIL 113C ₁ . The FIL 113C ₂ receives the signal OSC ₂ from the orthogonalizing unit 112C. Then, FIL113C ₂ is selectively passes the components of the angular frequency of the signal _{OSC 2 (ω SH -ω C)} , and outputs a signal PSC _2.

The signal PSC ₂ output from the FIL 113C ₂ is expressed by the following equation (13).
PSC ₂ (t) = A (t) · cos [θ _S (t)]
= A (t) · cos [ω _SH t−θ _C (t) + Δθ ₁ (ω _C ) −Δθ ₂ (ω _C )]
= A (t) · cos [ω _SH t− (ω _C t + φ ₀ ) + Δθ (ω _C )] (13)

Here, the phase shift Δθ (ω _C ) has an angular frequency dependency. This phase shift Δθ (ω _C ) is determined by the configuration of the band limiting filter 111 and the FIL 113C ₁ and FIL 113C ₂ . In the third embodiment, the phase shift Δθ (ω _C ) is assumed to generate the phase shift Δθ _{0 in} the signal having the angular frequency ω _C0 as in the first embodiment.

Returning to FIG. 13, the phase calculation unit 120C calculates the phase θ _C (t) of the pilot signal PS based on the signal PSC ₁ and the signal PSC ₂ from the orthogonal signal generation unit 110C. In such a calculation, the phase calculation unit 120C, for example, by such performs calculation of arctan like for the signal PSC ₁ and the signal PSC _2, reflecting the pilot signal PS, if the same phase theta _CE of the first embodiment ( t) is calculated.

The phase θ _CE (t) calculated in this way is output from the phase calculation unit 120C to the generation unit 130 and the phase correction unit 140 as the signal PHA.

<Operation>
Next, a signal processing operation in the signal processing device 100C configured as described above will be described.

When the signal SIA from the signal source 910 is received by the signal processing device 100C via the input terminal 191, the signal SIA is supplied to the orthogonal signal generation unit 110C in the signal processing device 100C (see FIG. 13). In the orthogonal signal generation unit 110C that receives the supply of the signal SIA, first, the band limiting filter 111 selectively passes signal components in a predetermined frequency band including the angular frequency ω _C in the signal SIA, and the frequency band is limited. The band-limited signal LSI is sent to the orthogonalizing unit 112C (see FIG. 14). As a result, even when the signal SIA has a signal component widely in a frequency region larger than the angular frequency ω _C as shown by a two-dot chain line in FIG. 16, for example, as shown in FIG. The frequency band of the component is limited.

Upon receiving the band limited signal LSI, the orthogonalizing unit 112C generates _two signals OSC ₁ and OSC ₂ that are orthogonal to each other based on the band limited signal LSI, and sends them to the FILs 113C ₁ and 113C ₂ (see FIG. 14). Here, as shown in FIG. 18, each of the signals OSC _j (j = 1, 2) has a signal component PSM _j having an angular frequency (ω _SH −ω _C ) as a signal component corresponding to the pilot signal PS and The signal component PSP _j of the angular frequency (ω _SH + ω _C ) is included.

In the present embodiment, the orthogonalizing unit 112C performs frequency conversion of the band limited signal LSI. For this reason, as shown by the two-dot chain line in FIG. 16 described above, the signal component PSM _j and the signal that can be generated when the frequency conversion of the signal SIA having a signal component widely in the frequency region higher than the angular frequency ω _C is performed. It is possible to prevent noise from being mixed into the component PSP _j (see the one-dot chain line in FIG. 18).

Subsequently, FIL113C ₁ which has received the signal OSC ₁ is the component of the angular frequency of the signal _{OSC 1 (ω SH -ω C)} , i.e., selectively pass a signal component corresponding to the pilot signal PS, the sampling angular frequency omega _SM1 The signal PSC ₁ is output to the phase calculation unit 120C. Further, FIL113C ₂ which has received the signal OSC ₂ is the component of the angular frequency of the signal _{OSC 2 (ω SH -ω C)} , i.e., selectively pass a signal component corresponding to the pilot signal PS, the sampling angular frequency omega _SM1 The signal PSC ₂ is output to the phase calculation unit 120C (see FIG. 14).

Here, the signal PSC ₁ has a waveform represented by the above-described equation (12). On the other hand, the signal PSC ₂ has a waveform represented by the above-described equation (13).

The phase calculation unit 120C that receives the signals PSC ₁ and PSC ₂ operates as described above to calculate the phase θ _CE reflecting the pilot signal PS. The phase θ _CE calculated in this way is sent to the generation unit 130 and the phase correction unit 140 as a signal PHA (see FIG. 13).

Thereafter, as in the case of the signal processing device 100A of the first embodiment, generator 130 which receives the signal PHA generates the generated angular frequency omega _CE, and sends to the phase correcting section 140 as signal FRQ (see FIG. 13). The phase correction unit 140 that receives the signal FRQ and the signal PHA from the phase calculation unit 120C calculates the phase θ _C (t) of the signal PS. The phase θ _C (t) calculated in this way is sent as a signal PHM from the phase correction unit 140 to the reference signal generation unit 150 (see FIG. 13).

The reference signal generation unit 150 that has received the signal PHM generates a reference signal BSA having an angular frequency of 2ω _C based on the signal PHM, as in the case of the signal processing device 100A of the first embodiment. The reference signal BSA generated in this way is output to the outside via the output terminal 192 (see FIG. 13).

As described above, in the third embodiment, as in the case of the first embodiment, from the signal SIA including the pilot signal PS of the angular frequency ω _C , the feedback loop in the PLL system and the reference for phase generation The phase θ _C (t) of the pilot signal PS is derived without using the base signal. Therefore, it is possible to generate the reference signal BSA that is easily and quickly synchronized with the pilot signal PS.

  In the third embodiment, the orthogonal signal generation unit 110C corrects the frequency characteristic of the phase shift that occurs when the pilot signal PS is orthogonalized and extracted based on the angular frequency generated by the generation unit 130. . For this reason, even when the angular frequency of the pilot signal PS varies, it is possible to generate the reference signal BSA that is accurately synchronized with the pilot signal PS.

  In the third embodiment, since orthogonalization is performed while performing frequency conversion in the orthogonalization unit 112C, the amount of calculation can be reduced compared to the case of orthogonalization using Hilbert transform or the like.

  Further, in the third embodiment, since the band limited signal LSI whose band is limited by the band limiting filter 111 is orthogonalized while performing frequency conversion, noise mixing in the frequency conversion result of the pilot signal PS is reduced. Can be made.

In the third embodiment, the phase θ _CE (t) calculated by the phase calculation unit 120C is corrected by the phase correction unit 140, but the phase corrected by the phase calculation unit 120C is calculated. In this way, the phase correction unit 140 may be omitted.

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

<Configuration>
FIG. 19 is a block diagram illustrating a schematic configuration of a signal processing device 100D according to the fourth embodiment. Similar to the signal processing apparatus 100C in the third embodiment, the signal processing apparatus 100D receives and processes the signal SIA output from the signal source 910 via the input terminal 191 and receives the reference signal BSA from the output terminal 192. As the output device.

  As illustrated in FIG. 19, the signal processing device 100D includes a frequency generation device 180D instead of the frequency generation device 180C and a frequency conversion control unit instead of the phase correction unit 140, as compared with the signal processing device 100C described above. Only the point provided with 146 is different. The frequency generation device 180D includes the quadrature signal generation unit 110D instead of the quadrature signal generation unit 110C and the phase calculation unit 120D instead of the phase calculation unit 120C as compared with the frequency generation device 180C described above. Is different. Hereinafter, description will be made mainly focusing on these differences.

  As illustrated in FIG. 20, the orthogonal signal generation unit 110D is different from the orthogonal signal generation unit 110C in that an orthogonalization unit 112D is provided instead of the orthogonalization unit 112C. As shown in FIG. 21, the orthogonalizing unit 112D is different from the orthogonalizing unit 112C only in that an oscillating unit 210D is provided instead of the oscillating unit 210C.

The oscillation unit 210D generates a sine wave having an angular frequency ω _SHM specified by the signal FTC from the frequency conversion control unit 146, whereby the signal OTV ₁ to be supplied to the multiplication unit 220 ₁ and the multiplication unit 220 ₂ are supplied. A signal OTV ₂ to be supplied is generated. In the fourth embodiment, the signal OTV ₁ and the signal OTV ₂ are expressed by the following equations (14) and (15).
OTV ₁ (t) = B ₀ · cos (ω _SHM · t) (14)
OTV ₂ (t) = B ₀ · sin (ω _SHM · t) (15)
Here, B ₀ is a constant.

Note that the angular frequency ω _SHM is a phase given to the signal of the angular frequency (ω _SHM −ω _C ) by a pair of the band limiting filter 111 and the FIL 113C ₁ or a pair of the band limiting filter 111 and the FIL 113C _2. The frequency conversion control unit 146 determines the shift Δθ to be a predetermined value Δθ ₀ .

As a result, the signals PSD ₁ and PSD ₂ output from the orthogonal signal generation unit 110D are expressed by the following equations (16) and (17).
PSD ₁ (t) = A (t) · sin [ω _SHM t− (ω _C t + φ ₀ ) + Δθ ₀ ] (16)
PSD ₂ (t) = A (t) · cos [ω _SHM t− (ω _C t + φ ₀ ) + Δθ ₀ ] (17)

Returning to FIG. 19, the phase calculation unit 120D performs pilot signals based on the signals PSD ₁ and PSD ₂ from the quadrature signal generation unit 110D and the angular frequency ω _SHM specified by the signal FTC from the frequency conversion control unit 146. The PS phase θ _C (t) is calculated. At the time of such calculation, the phase calculation unit 120D performs, for example, an arctan operation on the signal PSD ₁ and the signal PSD ₂ to calculate the phase θ _C (t).

The phase θ _C (t) calculated in this way is output as a signal PHM from the phase calculation unit 120D to the generation unit 130 and the reference signal generation unit 150.

Frequency conversion control unit 146 receives signal FRQ from generation unit 130. Then, the frequency conversion control unit 146 is provided based on the generated angular frequency ω _CE received as the signal FRQ, by a pair of the band limiting filter 111 and the FIL 113C ₁ or a pair of the band limiting filter 111 and the FIL 113C _2. phase shift [Delta] [theta] is, determine the angular frequency omega _SHM for a predetermined value [Delta] [theta] ₀ and becomes the angular frequency (ω _SHM -ω _CE). The angular frequency ω _SHM obtained in this way is output as a signal FTC to the quadrature signal generation unit 110D (more specifically, the oscillation unit 210D) and the phase calculation unit 120D.

  In the fourth embodiment, the signal PHM output from the phase calculation unit 120D is directly received by the reference signal generation unit 150.

<Operation>
Next, a signal processing operation in the signal processing device 100D configured as described above will be described.

When the signal SIA from the signal source 910 is received by the signal processing device 100D via the input terminal 191, the signal SIA is supplied to the orthogonal signal generation unit 110D in the signal processing device 100D (see FIG. 19). In the orthogonal signal generation unit 110D that is supplied with the signal SIA, the band limiting filter 111 selectively passes signal components in a predetermined frequency band including the angular frequency ω _C in the signal SIA, and the frequency band is limited. The limit signal LSI is sent to the orthogonalization unit 112D (see FIG. 20).

The orthogonalizing unit 112D that has received the band limited signal LSI generates _two signals OSD ₁ and OSD ₂ that are orthogonal to each other based on the band limited signal LSI and the signal FTC from the frequency conversion control unit 146 as described above. , FIL113C ₁ and 113C ₂ (see FIG. 21). Subsequently, FIL113C ₁ which has received the signal OSD ₁ is the component of the angular frequency (ω _SHM -ω _C) in the signal OSD _1, i.e., selectively pass a signal component corresponding to the pilot signal PS, phase as the signal PSD ₁ Output to the calculation unit 120D. Further, FIL113C ₂ which has received the signal OSD ₂ is the component of the angular frequency (ω _SHM -ω _C) in the signal OSD _2, i.e., selectively pass a signal component corresponding to the pilot signal PS, phase as the signal PSD ₂ It outputs toward calculation part 120D (refer FIG. 20).

The phase calculation unit 120D that has received the signals PSD ₁ and PSD ₂ operates as described above to calculate the phase θ _C (t) of the pilot signal PS. The phase θ _C (t) calculated in this way is sent as a signal PHM to the generation unit 130 and the reference signal generation unit 150 (see FIG. 19).

The generation unit 130 that has received the signal PHM generates a generation angular frequency ω _CE at each time point as in the case of the first embodiment, and sends it to the frequency conversion control unit 146 as the signal FRQ. The frequency conversion control unit 146 that has received the signal FRQ, based on the generated angular frequency ω _CE received as the signal FRQ, sets the band limiting filter 111 and the FIL 113C ₁ for the signal of the angular frequency (ω _SHM −ω _CE ). Alternatively, the angular frequency ω _SHM at which the phase shift Δθ given by the combination of the band limiting filter 111 and the FIL 113C ₂ becomes the predetermined value Δθ ₀ is obtained. The angular frequency ω _SHM thus obtained is sent as a signal FTC to the quadrature signal generation unit 110D (more specifically, the oscillation unit 210D) and the phase calculation unit 120D (see FIG. 19).

Due to the operation of the control loop formed by the orthogonal signal generation unit 110D, the phase calculation unit 120D, the generation unit 130, and the frequency conversion control unit 146, the phase calculation unit 120D causes the phase correction unit 140 in the third embodiment described above. As a result, a value reflecting the phase θ _C (t) of the pilot signal PS is output with the same accuracy as the signal PHM output from. In this sense, in the fourth embodiment, an output signal from the phase calculation unit 120D is described as a signal PHM.

The reference signal generator 150 that has received the signal PHM generates a reference signal BSA having an angular frequency of 2ω _C based on the signal PHM, as in the case of the third embodiment. The reference signal BSA generated in this way is output to the outside via the output terminal 192 (see FIG. 19).

As described above, in the fourth embodiment, as in the case of the third embodiment described above, from the signal SIA including the pilot signal PS of the angular frequency ω _C , for the feedback loop in the PLL system and the phase generation The phase θ _C of the pilot signal PS is derived without using the base signal serving as a reference for the above. Therefore, it is possible to generate the reference signal BSA that is easily and quickly synchronized with the pilot signal PS.

  In the fourth embodiment, the orthogonal signal generation unit 110D controls the frequency conversion in the orthogonalization unit 112D so that the phase shift generated when the pilot signal PS is orthogonalized and extracted becomes a predetermined value. Therefore, even when the angular frequency of the pilot signal PS varies, it is possible to generate the reference signal BSA that is accurately synchronized with the pilot signal PS.

  Further, in the fourth embodiment, as in the case of the third embodiment, the orthogonalization unit 112D performs the orthogonalization while performing the frequency conversion. Therefore, the calculation amount is larger than the case of the orthogonalization using the Hilbert transform or the like. Can be reduced.

  In the fourth embodiment, as in the case of the third embodiment, the band limited signal LSI obtained by band limiting the signal SIA by the band limiting filter 111 is orthogonalized while performing frequency conversion. It is possible to reduce the mixing of noise into the frequency conversion result.

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

<Configuration>
FIG. 22 is a block diagram illustrating a schematic configuration of a signal processing device 100E according to the fifth embodiment. The signal processing apparatus 100E receives and processes the signal SIA output from the signal source 910 via the input terminal 191 and outputs a signal MPS that reproduces the angular frequency and amplitude of the pilot signal PS included in the signal SIA. It is a device that outputs from a terminal 192.

  As shown in FIG. 22, the signal processing device 100E differs from the signal processing device 100A described above only in that a gain correction unit 160 is provided instead of the phase correction unit 140 and the reference signal generation unit 150. Hereinafter, this difference will be mainly described.

Note that the FIL 113A ₁ (see FIG. 3) in the orthogonal signal generation unit 110A has an angular frequency dependency of the gain. In the fifth embodiment, the angular frequency dependence of the gain of the FIL 113A ₁ is as shown in FIG.

Returning to FIG. 22, the gain correction unit 160 amplifies the signal PSA ₁ output from the orthogonal signal generation unit 110 </ b> A with an amplification factor determined based on the generation angular frequency ω _CM reported by the signal FRQ from the generation unit 130. To do. As shown in FIG. 24, the gain correction unit 160 having such a function includes an amplification unit 161 as an amplitude correction calculation unit and a gain control unit 162.

The amplifying unit 161 amplifies the signal received at the A terminal with the amplification factor specified by the signal received at the B terminal, and outputs the amplification result from the C terminal. Here, amplification section 161 receives signal PSA ₁ from quadrature signal generation section 110A at the A terminal and receives signal GCT from gain control section 162 at the B terminal. The gain correction signal MPS is output from the C terminal.

The gain control unit 162 includes a gain correction table 163 serving as a storage unit. In the gain correction table 163, an amplification factor A (ω) determined in correspondence with the angular frequency ω as shown in FIG. 25 is registered in advance. Here, as the amplification factor A (ω), a value that cancels the angular frequency dependence of the gain of the FIL 113A ₁ shown in FIG. 23 is registered.

Gain control unit 162 receives signal FRQ from generation unit 130. Then, the gain control unit 162 reads the amplification factor A (ω _CE ) with reference to the gain correction table 163 based on the generated angular frequency ω _CE received as the signal FRQ. The amplification factor A (ω _CE ) read out in this way is output to the amplifying unit 161 as a signal GCT.

  As a result, the amplification unit 161 outputs a signal having an amplitude that is exactly proportional to the amplitude of the pilot signal PS included in the signal SIA. The signal thus amplified by the amplifying unit 161 is output to the outside through the output terminal 192 as the signal MPS.

<Operation>
Next, a signal processing operation in the signal processing device 100E configured as described above will be described.

When the signal SIA from the signal source 910 is received by the signal processing device 100E via the input terminal 191, the signal SIA is supplied to the orthogonal signal generation unit 110A in the signal processing device 100E (see FIG. 22). The orthogonal signal generation unit 110A that has received the signal SIA generates signals PSA ₁ and PSA ₂ corresponding to the pilot signal PS in the same manner as in the first embodiment. Then, the signal PSA ₁ is sent to the phase calculation unit 120A and the gain correction unit 160, and the signal PSA ₂ is sent to the phase calculation unit 120A (see FIG. 22).

The phase calculation unit 120A that receives the signals PSA ₁ and PSA ₂ performs, for example, an arctan operation on the signal PSA ₁ and the signal PSA ₂ to calculate the phase θ _C (t). The phase θ _C (t) calculated in this way is sent as a signal PHA from the phase calculation unit 120A to the generation unit 130 (see FIG. 22).

Generator 130 which receives the signal PHA may operate in the same manner as in the first embodiment, to produce a product angular frequency omega _CE. The generated angular frequency ω _CE generated in this way is sent to the gain correction unit 160 as a signal FRQ (see FIG. 22).

In the gain correction unit 160 that receives the signal FRQ, the gain control unit 162 reads the amplification factor A (ω _CE ) by referring to the gain correction table 163 based on the generated angular frequency ω _CE received as the signal FRQ, The data is sent as GCT to the amplification unit 161 (see FIG. 24). Receiving the signal GCT, the amplification unit 161 amplifies the signal PSA ₁ from the orthogonal signal generation unit 110A with the amplification factor A (ω _CE ) received as the signal GCT. The amplification result is output to the outside through the output terminal 192 as a signal MPS (see FIG. 24).

As described above, in the fifth embodiment, as in the case of the first embodiment described above, the signal SIA including the pilot signal PS having the angular frequency ω _C is used to generate a feedback loop and phase in the PLL system. The phase θ _C (t) of the pilot signal PS is derived without using the base signal serving as a reference for. Therefore, it is possible to generate the signal MPS that is synchronized with the pilot signal PS easily and quickly.

  In the fifth embodiment, the orthogonal signal generation unit 110A corrects the frequency characteristic of the gain generated when the pilot signal PS is orthogonalized and extracted based on the angular frequency generated by the generation unit 130. For this reason, even when the angular frequency of the pilot signal PS varies, it is possible to generate the signal MPS having an amplitude that is exactly proportional to the amplitude of the pilot signal PS.

[Modification of Embodiment]
The present invention is not limited to the first to fifth embodiments described above, and various modifications are possible.

For example, in the first to fourth embodiments, a signal having an angular frequency 2ω _C that is twice the angular frequency ω _C of the pilot signal PS is generated as the reference signal. On the other hand, a signal having an angular frequency that is an arbitrary multiple of the angular frequency ω _C can be generated as a reference signal in accordance with the mode of the signal component to be processed in the signal from the signal source. Furthermore, in the case of the third embodiment, a signal having an angular frequency obtained by an arbitrary linear combination of the angular frequency ω _C and the shift angular frequency can be generated as the reference signal.

  In the first to fourth embodiments described above, one type of reference signal is generated. However, a plurality of types of reference signals may be generated.

  In the third and fourth embodiments, the low frequency signal is extracted and used from the signals corresponding to the frequency converted pilot signal PS. However, the high frequency signal is extracted. You may make it use it.

In the fifth embodiment, the gain of the in-phase signal PSA ₁ of the pilot signal PS is corrected. However, the gain of the signal PSA ₂ orthogonal to the signal PSA ₁ may be corrected.

  The modification of the first embodiment to the second embodiment can also be applied to the third or fourth embodiment, and the modification of the first embodiment to the third or fourth embodiment can be applied to the second embodiment. It can also be applied to the embodiment.

  Moreover, the deformation | transformation to 5th Embodiment with respect to 1st Embodiment can also be applied to 2nd-4th Embodiment, and the deformation | transformation to 2nd-4th Embodiment with respect to 1st Embodiment is 5th Embodiment. It can also be applied to.

  The first embodiment and the fifth embodiment can be combined.

  The signal processing apparatus according to the first to fifth embodiments can be realized by executing a program in a DSP (Digital Signal Processor). These programs may be acquired in the form recorded on a portable recording medium such as a CD-ROM or DVD, or may be acquired in the form of delivery via a network such as the Internet. Good.

1 is a block diagram illustrating a schematic configuration of a signal processing device according to a first embodiment of the present invention. It is a figure for demonstrating the frequency distribution of the signal from the signal source assumed in 1st Embodiment. It is a block diagram which shows the structure of the orthogonal signal generation part in FIG. It is a block diagram which shows the structure of the orthogonalization part in FIG. It is a figure for demonstrating the example of the frequency dependence of the phase shift of the filter (FIL) of FIG. It is a block diagram for demonstrating the structure of the production | generation part in FIG. It is a block diagram for demonstrating the structure of the phase correction part in FIG. It is a figure for demonstrating the registration content of the phase correction table in FIG. It is a block diagram which shows the structure of the reference signal production | generation part in the apparatus of FIG. It is a block diagram which shows the schematic structure of the signal processing apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the structure of the orthogonal signal generation part in FIG. It is a figure for demonstrating the variability of the frequency dependence of the phase shift of the filter (FIL) of FIG. It is a block diagram which shows the schematic structure of the signal processing apparatus which concerns on 3rd Embodiment of this invention. It is a block diagram which shows the structure of the orthogonal signal generation part in FIG. It is a block diagram which shows the structure of the orthogonalization part in FIG. It is a figure for demonstrating the frequency distribution of the signal from the signal source assumed in 3rd Embodiment. It is a figure for demonstrating the frequency distribution of the band limitation signal output from a band limitation filter. It is a figure for showing the frequency conversion result by the orthogonalization part of FIG. It is a block diagram which shows schematic structure of the signal processing apparatus which concerns on 4th Embodiment of this invention. It is a block diagram which shows the structure of the orthogonal signal generation part in FIG. It is a block diagram which shows the structure of the orthogonalization part in FIG. It is a block diagram which shows the schematic structure of the signal processing apparatus which concerns on 5th Embodiment of this invention. FIG. 23 is a diagram for describing an example of frequency dependence of a filter (FIL) gain in the apparatus of FIG. 22; It is a block diagram for demonstrating the structure of the gain correction | amendment part in FIG. It is a figure for demonstrating the registration content of the gain correction table in FIG.

Explanation of symbols

100A to 100E ... Signal processing device 111 ... Band limiting filter (band limiting means)
112A to 112D ... Orthogonalizing unit (orthogonalizing means)
113A ₁ , 113A ₂ ... Filter (filter means)
113B ₁ , 113B ₂ ... Filter (filter means)
113C ₁ , 113C ₂ ... Filter (filter means)
120A, 120C ... Phase calculation unit (phase calculation means)
130: Generation unit (generation means)
131: Frequency calculation unit (first stage calculation means)
132 ... Low-pass filter (second stage calculation means)
140 ... Phase correction unit (correction means)
141... Adder (phase correction calculation means)
143 ... Phase correction table (storage means)
145 ... Filter control section (correction means)
146 ... Frequency conversion control unit (correction means)
160... Gain correction unit (correction means)
161: Amplifying unit (amplitude correction calculation means)
163... Gain correction table (storage means)
180A-180D ... Frequency generator

Claims (20)

A frequency generation device that generates a frequency corresponding to a predetermined signal included in an input signal,
Orthogonalization means for performing orthogonalization on at least the predetermined signal and generating a first orthogonalized signal and a second orthogonalized signal in which components corresponding to the predetermined signal are orthogonal to each other;
A first signal included in the first orthogonal signal and having a phase reflecting the phase of the predetermined signal and a second signal included in the second orthogonal signal and orthogonal to the first signal are selectively selected. Filter means for passing through;
Phase calculating means for calculating a phase of the signal reflecting the predetermined signal based on the first signal and the second signal;
Comprising a,; based on the calculation result of the phase calculation means, and generating means for generating a frequency corresponding to the predetermined signal
The orthogonalization means performs a frequency shift according to a frequency shift setting in addition to the orthogonalization.
A frequency generator characterized by the above. The generating means includes
First stage calculation means for calculating a first stage frequency related to the predetermined signal based on a calculation result by the phase calculation means;
Second stage calculating means for calculating a second stage frequency related to the predetermined signal by removing unnecessary fluctuation components included in the calculation result by the first stage calculating means;
The frequency generation device according to claim 1, further comprising: The frequency generation device according to claim 1 , further comprising: a band limiting unit that generates a band limiting signal that limits a frequency band of the input signal and supplies the band limiting signal to the orthogonalizing unit. A frequency generation device according to any one of claims 1 to 3 ;
Correction means for correcting, as a correction target signal, a phase information signal output from the phase calculation means or at least one of the first signal and the second signal based on the frequency generated by the frequency generation device;
A signal processing apparatus comprising: The correction target signal is the phase information signal output from the phase calculating means,
The correction unit controls correction of a phase shift between a phase of the predetermined signal derived from a frequency characteristic of the filter unit in the phase information signal and a calculation result by the phase calculation unit;
The signal processing apparatus according to claim 4 . The correction means includes
Storage means in which the relationship between the frequency value of the predetermined signal and the phase amount to be corrected is registered;
Phase correction calculation means for determining a phase correction amount corresponding to the generation result by the generation means based on the generation result by the generation means and the registered content in the storage means;
The signal processing apparatus according to claim 5 , further comprising: The filter means changes a frequency characteristic related to a phase change according to a phase characteristic setting,
The phase calculating means is configured in the standard state where the frequency of the predetermined signal is a standard frequency, the frequency shift setting is a standard frequency shift setting, and the phase characteristic setting of the filter means is a standard phase setting. Calculate the phase in consideration of the standard phase change amount derived from the filter means,
The correction unit performs phase characteristic setting on the filter unit such that the phase change amount derived from the filter unit corresponding to the frequency of the generation result by the generation unit becomes the standard phase change amount.
The signal processing apparatus according to claim 5 . The phase calculating means considers a standard phase change amount derived from the filter means in a standard state where the frequency of the predetermined signal is a standard frequency and the frequency shift setting is a standard frequency shift setting. Perform the calculation
The correction unit matches the frequency of the frequency conversion result of the predetermined signal by the orthogonalizing unit in the standard state with the frequency after the frequency shift of the frequency signal generated by the generating unit by the orthogonalizing unit. Performing frequency shift setting for the orthogonalizing means;
The signal processing apparatus according to claim 5 . The correction target signal is at least one of the first signal and the second signal,
The correction unit controls correction of at least one of the phase and the amplitude of the correction target signal derived from the frequency characteristic of the orthogonalizing unit in the correction target signal.
The signal processing apparatus according to claim 4 . The correction means includes
Storage means in which the relationship between the frequency value of the predetermined signal and the amplitude amount to be corrected is registered;
Amplitude correction calculation means for determining an amplitude correction amount corresponding to the generation result by the generation means based on the generation result by the generation means and the registered content in the storage means;
The signal processing apparatus according to claim 9 , comprising: The filter means changes the frequency characteristic of the gain according to the gain characteristic setting,
The correcting means is the standard gain state when the frequency of the predetermined signal is a standard frequency, the frequency shift setting is a standard frequency shift setting, and the gain characteristic setting of the filter means is a standard gain setting. A gain characteristic setting is performed for the filter unit so that a standard gain which is a gain of the filter unit and a gain of the filter unit with respect to a signal having a frequency generated by the generation unit match.
The signal processing apparatus according to claim 10 . The orthogonalizing means changes the gain characteristics according to the gain setting,
The correction unit performs gain setting for the orthogonalizing unit to cancel the change in the gain characteristic of the filter unit accompanying the change in the frequency shift result of the frequency of the predetermined signal.
The signal processing apparatus according to claim 10 . The filter means changes a frequency characteristic with respect to a phase change according to a phase characteristic setting,
The correcting means is the standard phase state in which the frequency of the predetermined signal is a standard frequency, the frequency shift setting is a standard frequency shift setting, and the phase characteristic setting of the filter means is a standard phase setting. A phase characteristic setting is made for the filter means to match a standard phase change that is a phase change in the filter means and a phase change in the filter means with respect to a frequency signal generated as a result of the generation means.
The signal processing device according to claim 10 , wherein the signal processing device is a signal processing device. The orthogonalizing means changes the phase characteristics according to the phase setting,
The correction unit performs phase setting for the orthogonalizing unit to cancel the change in the phase characteristic of the filter unit accompanying the change in the frequency shift result of the frequency of the predetermined signal.
The signal processing apparatus according to claim 10 , wherein: A frequency generation method for generating a frequency corresponding to a predetermined signal included in an input signal,
An orthogonalization step of performing a process of orthogonalizing at least the predetermined signal and generating a first orthogonal signal and a second orthogonal signal in which components corresponding to the predetermined signal are orthogonal to each other;
A first signal included in the first orthogonal signal and having a phase reflecting the phase of the predetermined signal and a second signal included in the second orthogonal signal and orthogonal to the first signal are selectively selected. A filtering step to pass through;
A phase calculating step of calculating a phase of a signal reflecting the predetermined signal based on the first signal and the second signal;
Comprising a,; based on the calculation result in the phase calculating step, a generation step of generating a frequency corresponding to the predetermined signal
In the orthogonalization step, in addition to the orthogonalization, a frequency shift according to a frequency shift setting is performed.
A frequency generation method characterized by the above. A frequency generation step of generating a frequency corresponding to a predetermined signal by the frequency generation method according to claim 15 ;
A correction step of correcting at least one of the phase information signal generated in the phase calculation step or the first signal and the second signal as a correction target signal based on the frequency generated in the frequency generation step;
A signal processing method comprising: A frequency generation program for causing a calculation means to execute the frequency generation method according to claim 15 . A signal processing program for causing a calculation means to execute the signal processing method according to claim 16 . 18. A recording medium in which the frequency generation program according to claim 17 is recorded so as to be readable by an arithmetic means. 19. A recording medium in which the signal processing program according to claim 18 is recorded so as to be readable by an arithmetic means.

Images