JP4724864B2 - Oscillation element array oscillation phase control apparatus and control method therefor - Google Patents

Description

  The present invention relates to an oscillation phase control device for an oscillation element array that controls the oscillation phase of the oscillation elements that constitute the oscillation element array, and a control method therefor.

  Electronic devices (oscillators, oscillators, etc.) that generate millimeter-wave or higher-frequency signals of millimeter-wave or higher are inherently small in output power because of their fine structure. Therefore, it is necessary to synthesize output power by integrating a large number of oscillators. For this reason, it has been proposed to obtain a combined output power of a plurality of oscillators by arranging high-frequency oscillators in a one-dimensional or two-dimensional array.

  As described above, a system in which a plurality of oscillators are arranged and adjacent oscillators are allowed to interact with each other by some method (for example, electromagnetic coupling) is known to be applied in many fields. For example, a millimeter wave beam scanning circuit or a motion pattern generator (CPG: Central Pattern Generator) in Robotex is widely known. By applying this system to a movement pattern generator, movements such as reptiles and fish, and movements such as flapping birds and insects can be reproduced.

  However, when there is a variation in the phase difference of the oscillation signals between the oscillators arranged in an array, sufficient combined output power cannot be obtained. Therefore, it is necessary to synchronize the phase difference of the oscillation signal between the oscillators.

  For example, when controlling the beam directivity (beam pattern) in an antenna system using an oscillator arranged in an array (hereinafter referred to as an “oscillator array”), the oscillation phase difference between adjacent oscillators is set to a desired value. Must be a constant value. For example, in the case of a one-dimensional oscillator array in which N oscillators 101 are arranged as shown in FIG. 8, when a certain phase difference is realized between the beams 103 output from each oscillator, The equiphase surface 104 is determined, and the intensity of the beam is maximized in a direction perpendicular to the equiphase surface 104. Therefore, the directivity of this beam can be controlled by controlling the oscillation phase of each oscillator.

  Conventionally, two types of control methods for oscillators are known. The first is a technique (prior art (1)) in which each oscillator 101 is individually controlled and the directivity of the beam is controlled by manipulating all the oscillation phases separately.

  The second method is to control only a small number of oscillators 101 in the one-dimensional oscillator array (for example, the oscillators 101 at both ends of the oscillator array) and autonomously control the oscillation phase of the entire oscillator (conventional technology (2 )).

  Here, the prior art (2) will be described in detail with reference to FIG. FIG. 9 is a block diagram of an oscillation phase control device for a one-dimensional oscillator array of the prior art (2). As shown in FIG. 9, the oscillation phase control device of the prior art (2) includes a one-dimensional oscillator array composed of N (two or more) self-excited oscillators 101 and a self-excited oscillator 101. It has N antennas connected. Although not shown in FIG. 9, a plurality of oscillators 101 each connected to the antenna 102 are arranged in the broken line area. In order to control the beam directivity of the one-dimensional oscillator array with this prior art (2), it is necessary that all the oscillators in the one-dimensional oscillator array achieve attraction locking (mutual injection locking) by interaction. .

In the oscillation phase control apparatus of the one-dimensional oscillator array shown in FIG. 9, the equation showing the time change of the oscillation phase θ _i of the i-th (i is a natural number) oscillator from the left end is called an operation equation. It is known that the operation equation of the i-th oscillator of the prior art (2) shown in FIG. 9 is given by a differential equation as shown below under a certain condition (for example, see Non-Patent Document 1). . When the time variation (= dθ _i / dt) of the natural oscillation phase of the i-th oscillator is represented by adding dots on θ _i , the following equation is obtained.

で表される。

It is represented by

Here, θ _i , ω _i , and A _i represent the oscillation phase, natural angular velocity, and oscillation amplitude of the i-th oscillator, respectively. Further, κ and Φ are constants corresponding to the strength and delay of the interaction between the oscillators, and their values are determined by the configuration of each oscillator and the oscillator array. Now, since the coupling between the oscillators can be normally adjusted to be Φ˜0, the case where Φ = 0 is described below.

In the system of the prior art (2), it is assumed that there is no delay in the oscillation signal output from each oscillator, and it is assumed that the constant Φ = 0 regarding the delay on the left side of Equation (1). Further, by normalizing the oscillation phase θ _i , the constant κ = 1 regarding the interaction strength between the oscillators is obtained.

By the way, this prior art (2) aims to obtain a uniform oscillation phase difference θ _i −θ _{i + 1} ≡Δφ among all oscillators in a steady state. For this reason, it is usually necessary to make the characteristics of the oscillation frequency and oscillation amplitude of all the oscillators uniform. Therefore, the natural angular velocity ω _i and the oscillation amplitude A _i of the oscillator 101 can be regarded as constants. Here, the natural angular velocity ω _i = Ω and the oscillation amplitude A _i = 1. By applying these conditions to the equation (1), it can be simplified as follows.

In the prior art (2), in equations (2) -1 and 3, the natural frequencies of the first oscillator 101 and the Nth oscillator 101 (that is, the natural angular velocity) so that ω ₁ = Ω + Δω, ω _N = Ω−Δω. ) Is essential. Δω is a displacement (also referred to as a displacement amount) of the natural angular velocities ω ₁ and ω _N of the oscillator 101 positioned at both ends of the oscillator array with respect to the natural angular velocities Ω of the i-th oscillator 101. The phase difference Δφ (= θ _i −θ _{i + 1} ) between the oscillators obtained in the steady state is always equal among all the oscillators. Therefore, a method of obtaining the phase difference Δφ between the oscillators in the steady state will be described using the simplest expression (2) -3.

First, for simplification, θ _N = φ _N + Ωt is substituted into the right side of Expression (2) -3, and coordinate conversion from θ _N to φ _N is performed. As described above, in the steady state, the one-dimensional oscillator array has a constant phase difference between an arbitrary oscillator 101 and the adjacent oscillator 101, and it is not necessary to consider a change in phase difference with time. That, phi _N is a constant that does not change with time. Here, when both sides of θ _N = φ _N + Ωt are differentiated with respect to time, φ _i is a constant, and therefore dθ _N / dt = Ω. By substituting dθ _N / dt = Ω into the left side of the equation obtained by transforming equation (2) -3, equation (3) indicating the relationship between the phase difference Δφ between adjacent oscillators and the angular velocity displacement Δω is obtained.

  Here, the relationship between the phase difference Δφ and the angular velocity displacement Δω in the equation (3) is shown in FIG. The vertical axis represents the phase difference Δφ, and the horizontal axis represents the angular velocity displacement Δω. In FIG. 10, a region surrounded by a broken line (| Δω | <1) is called a pull-in region, and when the angular velocity displacement Δω takes a value in this region in the prior art (2), each oscillator of the oscillator array In this state, the synchronization is brought in. In the prior art (2), areas other than the pull-in area (| Δω |> 1) are out-of-synchronization areas, and at this time, the oscillators in the oscillator array are not synchronized.

  In order to realize the control of the oscillation phase of the oscillator array in the prior art (2), it is important that the adjacent oscillators 101 are in a synchronized state with each other. That is, the angular velocity displacement Δω must be set in the pull-in region shown in the relationship diagram of the phase difference Δφ and the angular velocity displacement Δω in FIG. That is, it is a necessary condition that the absolute value of the angular velocity displacement Δω of the oscillators located at both ends of the oscillator array is smaller than 1.

  Based on the phase difference Δφ between the adjacent oscillators 101, an equiphase surface of the oscillation signal output from each oscillator 101 is obtained, and the beam pattern (beam directivity) of the oscillator array is determined.

  From the above equation modification, in the prior art (2), the phase difference between adjacent oscillators other than the oscillators at both ends of the oscillator array is set by setting the oscillation frequencies (angular velocities) of the oscillators positioned at both ends of the oscillator array to appropriate values. It can be understood that Δφ is controlled and the directivity of the beam is controlled.

P. Liao and RA York, “A New Phase-Shifterless Beam-Scanning Technique Using Arrays of Coupled Oscillators”, IEEE Trans. Microwave Theory Tech., Special issue on quasi-optical techniques, October 1993, vol. MTT-41, pp 1810-1815.

  By the way, in the prior art (1), each oscillator in the oscillator array is individually controlled. Therefore, it is necessary to add control means such as a phase shifter to all the oscillators to control them in a unified manner. If the oscillator array is large, it is difficult to realize economically and technically.

  In the prior art (2), for example, when all the oscillators constituting the oscillator array are synchronized with each other and the oscillation frequency is 10 GHz, the beam directivity is set to + 12.5 °, for example. Is set to. In that case, according to Non-Patent Document 1, the oscillation frequencies of the oscillators at both ends of the oscillator array are required to be 9.985 GHz and 10.15 GHz, respectively. This indicates that the frequency of the oscillators at both ends must be controlled with a high accuracy of several kHz, which is technically difficult.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to easily control the beam directivity of an oscillator array including a plurality of oscillators.

  In order to solve the above-described problems, the present invention electromagnetically couples a plurality of oscillation elements in an array and arranges the oscillation element array. First, the oscillation frequency of each oscillation element is selected to be a predetermined frequency. Next, an external synchronization signal having a frequency higher than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized is injected into the oscillation element located at one end of the oscillation element array. At the same time, an external synchronization signal having a frequency lower than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized is injected into the oscillation element located at the other end of the oscillation element array. Then, a plurality of oscillating elements excluding the oscillating elements positioned at least at the end of the oscillating element array are enabled to obtain an output.

  Thereby, with respect to the plurality of oscillators constituting the oscillator array, the phase difference between the plurality of oscillation elements excluding the oscillation elements positioned at least at the ends can be controlled.

  According to the oscillation phase control apparatus and the control method for an oscillator array according to the present invention, the frequency of the external synchronization signal applied to the oscillators at both ends of the oscillator array can be flexibly adjusted, and the oscillation phase of each oscillator of the oscillator array can be determined by the amplitude of the synchronization signal. Can be controlled. Therefore, it is possible to provide a control method based on the amplitude of the synchronization signal that has not existed so far, and to perform phase control with higher accuracy than in the prior art.

  Hereinafter, an example of the first embodiment of the present invention will be described with reference to FIGS. The oscillation phase control device of the oscillator array of this embodiment is an example applied to the oscillation phase control device of a one-dimensional oscillator array. 1 to 6, parts and variables corresponding to FIGS. 8 to 10 and Expressions (1) to (3) referred to in the description of the background art are denoted by the same reference numerals or symbols. Description is omitted.

  FIG. 1 is a block diagram showing a schematic configuration of an oscillation phase control device of a one-dimensional oscillator array. As shown in FIG. 1, the oscillation phase control device of the oscillator array of this embodiment has a configuration in which N oscillators 1 that self-oscillate at a predetermined angular velocity (frequency) are arranged in a line and adjacent oscillators are connected. is there. However, for convenience of explanation, reference numerals 1A and 1B are attached to the oscillators at both ends, and the order of the oscillators in the one-dimensional oscillator array is shown in parentheses. An antenna 2 for radiating signal radio waves is connected to all the oscillators 1 except for the oscillators 1A and 1B at both ends of the one-dimensional oscillator array and the second oscillator 1 from both ends. Although not shown in FIG. 1, the broken line portion of the oscillation phase control device of the one-dimensional oscillator array includes the third to (i−2) th oscillators 1 and (i + 2) to which the antenna 2 is connected. The first through (N-2) th oscillators 1 are connected. Here, i is a natural number smaller than N and larger than 1. Each oscillator is an example of the oscillation element recited in the claims, but is not limited to this example as long as it is an electronic device that generates a high-frequency signal.

  Further, the oscillation phase control device of the one-dimensional oscillator array shown in FIG. 1 includes oscillators 3A and 3B for injecting synchronization signals to the oscillators 1A and 1B located at both ends of the one-dimensional oscillator array, and the oscillators 3A, 3A, Variable amplifiers 4A and 4B for amplifying a signal output from 3B are provided. The oscillators 3A and 3B are an example of synchronization signal injection means described in the claims. For convenience of explanation, the oscillator 3A and the oscillator 3B are defined as the 0th and N + 1th oscillators.

  The self-excited oscillators 1, 1 </ b> A, 1 </ b> B have the same characteristics. As shown in FIG. 2A, for example, from a direct connection of a capacitor 11, a coil 12, a constant resistance element 13, and a nonlinear resistance element 14. It is configured. An output signal V based on the output voltage of the nonlinear resistance element 14 is obtained from the constant resistance element 13 and output to the antenna device 2. Note that the oscillator used in this embodiment has a PLL function that detects the phase difference between its own output signal and the input signal, and controls the frequency of the output signal to be constant based on the phase difference, thereby making the oscillation frequency constant. You may make it keep.

  FIG. 2B is an equivalent circuit showing a coupling state between the plurality of oscillators 1 shown in FIG. 2A, and has a configuration in which the oscillators 1 of the one-dimensional oscillator array shown in FIG. 1 are continuously connected. Show. From this circuit configuration, it can be understood that the adjacent oscillators 1 exert an electromagnetic action on each other, and the characteristics of the oscillation signal of each oscillator 1 change. Note that the equivalent circuit of the oscillator shown in FIGS. 2A and 2B and the equivalent circuit when the oscillators are combined are merely examples, and the present invention is not limited to this example.

Next, an operational equation for each oscillator when a synchronization signal is externally injected into the oscillators 1A and 1B at both ends of the one-dimensional oscillator array shown in FIG. 1 will be described. For example, the synchronization signal injected into the oscillator 1A and the oscillator 1B is a sine wave signal A _inj sin (Ω ± Δω) t. Here, when the amplitude A _inj = 1 and the angular velocity displacement Δω is sufficiently small (| Δω | <1), this means that the oscillator 101 (see FIG. 9) at both ends of the oscillator array itself is externally connected in the prior art (2). It is equivalent to the case where it is regarded as a synchronization signal from. In this case, the oscillation phase control device of the one-dimensional oscillator array shown in FIG. 1 is exactly the same as the oscillation phase control device of the oscillator array according to the prior art (2), and the oscillation of the oscillator array of the prior art (2). Equation (3) related to the phase control is established.

On the other hand, the present applicant proposes to control the operation of the one-dimensional oscillator array as (| Δω |> 1) in the synchronization signal A _inj sin (Ω ± Δω) t. That is, in the relationship between the angular velocity displacement Δω of the synchronization signal and the phase difference Δφ between the oscillators, the conventional technique (2) uses a lock-in, whereas in the present invention, an out-of-sync region (Out of lock). ) Is used to control the oscillation phase. When the oscillation phase control method according to the present invention is employed, the operation of the one-dimensional oscillator array is essentially different from that of the prior art (2). Hereinafter, an oscillation phase control method according to the present invention will be described.

The operational equation for each oscillator of the one-dimensional oscillator array shown in FIG. 1 is given by equation (1), as in the prior art (2). However, the 0th oscillator 3A and the (N + 1) th oscillator 3B positioned at both ends of the one-dimensional oscillator array are different from the oscillator 101 at both ends of the one-dimensional oscillator array of the prior art (2), and the synchronization signal A _inj sin (Ω It is necessary to change the equation in consideration of the application of ± Δω) t [| Δω |> 1)]. In other words, in addition to the conditions used in obtaining the equation (2), ω _i = Ω, A _i = 1 (1 <i <N), κ = 1, ω ₀ = Ω + Δω, ω _{N + 1} = Ω− The expression (1) is modified by adding the condition Δω, A ₀ = A _{N + 1} = A _inj . Then, the operational equations for the first oscillator 1A, the 2nd to (N-1) th oscillator 1 and the Nth oscillator 1B constituting the one-dimensional oscillator array shown in FIG. To be simplified.

Subsequently, when θ _i = Ωt + φ _i (i = 1,..., N) is applied to the left side of the equations (4) -1 to 3 and coordinate conversion from θ _{i to} φ _i is performed, the following is obtained. Become.

Next, the formula (5) with respect -1～3, the variable phi _i using techniques nonlinear transformation and averaging, when a mathematical approximation, the following substantially equivalent expression (6) -1 to 3 are obtained.

When the operation of the one-dimensional oscillator array of the present embodiment is in a steady state, there is no time change, and therefore the left side (dφ _i / dt) = 0 in Equation (6) -1 to 3 (θ _i = Ωt + φ _i) ). By substituting Ω as an example for the left side of Equation (6) -3, the phase difference Δφ (θ _i−1 −θ _i = φ _i−1 −φ _i ) is given by the following equation.

This equation (7) is important in that it supports the theory of the oscillation phase control method of the oscillator according to the present invention. From the equation (7), in the one-dimensional oscillator array shown in FIG. 1, unlike the prior art (2), the phase difference Δφ between adjacent oscillators is proportional to the square of the amplitude A _inj of the injected synchronization signal. It can be understood that it is inversely proportional to the angular velocity displacement Δω. That is, if the displacement Δω of the angular velocity of the synchronizing signal to be injected is fixed, the phase difference between the oscillators can be changed to a desired value only by adjusting the amplitude.

  The sine wave has been described as an example of the synchronization signal injected into the oscillators at both ends of the one-dimensional oscillator array. However, when a signal having a predetermined period such as a pulse wave and a rectangular wave is used, the same effect as the sine wave is obtained. Has been confirmed.

  Next, the operation of the one-dimensional oscillator array shown in FIG. 1 will be described with reference to FIG. FIG. 3 is a diagram for explaining the operation of the one-dimensional oscillator array, showing the configuration of the one-dimensional oscillator array in the upper stage, the oscillation phase characteristics in the middle stage, and the phase difference Δφ between adjacent oscillators in the lower stage.

  The oscillation phase characteristic 20 shown in the middle stage of FIG. 3 shows the relationship between the first to Nth oscillators 1 in the one-dimensional oscillator array of this embodiment and the corresponding oscillation phases. The vertical axis of the graph represents the oscillation phase. The horizontal axis represents the oscillator number. In this example, the oscillation frequencies of the oscillators 1A and 1B at both ends before the injection of the synchronization signal and the oscillation frequency of the oscillator 1 between them are each 10 GHz, for example, and the amplitude of the synchronization signal is set to a certain constant value. In this example, for convenience of explanation, data obtained from seven oscillators including the oscillators at both ends of the one-dimensional oscillator array are plotted.

  The oscillation phase characteristic 20 is obtained based on the equation (4) of the operation equation. It can be confirmed that the oscillation phase characteristic 20 is divided into a region having a constant gradient at a certain moment and a region where the oscillation phase is not stable. For example, the first oscillator 1A located at the end of the one-dimensional oscillator array (the frequency of the synchronization signal is high: 12 GHz) goes down to the Nth oscillator 1B (the frequency of the synchronization signal is low: 8 GHz). Further, since the oscillators 1A and 1B at both ends of the one-dimensional oscillator array are out of synchronization with each other, the oscillation phase is not stable. Further, the second and (N−1) th oscillators 1 adjacent to both ends of the one-dimensional oscillator array also have low oscillation phase stability. This is due to the influence of pull-in by the oscillators 1A and 1B at both ends. it is conceivable that.

  On the other hand, the relationship between the phase differences between adjacent oscillators in the one-dimensional oscillator array is as shown in the minimum phase difference characteristic 28 and the maximum phase difference characteristic 29 shown in the lower part of FIG. In this example, data (21 to 27) was plotted for seven oscillators at both ends and in the center. The minimum phase difference characteristic 28 and the maximum phase difference characteristic 29 represent the minimum phase difference and the maximum phase difference with the adjacent oscillator, respectively. From the example of FIG. 3, the phase difference characteristics 28 and 29 are the first oscillator 1A and the second oscillator 1 near the end of the one-dimensional oscillator array, and the (N-1) th oscillator 1 and the Nth oscillator. The phase difference acquired from 1B is large. On the other hand, the phase difference between the (i−1) -th, i-th and (i + 1) -th oscillators 1 at the center of the one-dimensional oscillator array is constant with the adjacent oscillators. In other words, it can be theoretically confirmed that the other oscillators except for the vicinity of the end of the one-dimensional oscillator array shown in FIG. 1 maintain a steady phase difference between the oscillation phases.

  Further, there is a difference in the values of the minimum phase difference characteristic 28 and the maximum phase difference characteristic 29 between both ends of the oscillator array and the oscillator near the center. This suggests that the phase difference from the adjacent oscillators obtained from the oscillators at both ends of the oscillator array fluctuates with time, and it can be understood that this is not a steady state.

  In addition to the oscillators 1A and 1B at both ends to which the synchronization signal is injected in the one-dimensional oscillator array, the phase difference between the adjacent oscillators obtained from the second and (N-1) th oscillators 1 adjacent thereto is also slightly large. It has become. This is considered to be an influence of pull-in by the oscillators 1A and 1B at both ends.

  By the way, as can be seen from the fact that the equation (4) is a function of time, the central oscillator 1 except for the vicinity of the end of the one-dimensional oscillator array maintains the phase difference between the adjacent oscillators in the steady state, The oscillation phase is changed every moment. That is, when the time variation of the oscillation phase is seen in the graph shown in the middle part of FIG. 3, the oscillation phase characteristic 20 moves along the vertical axis while maintaining a constant gradient.

  Further, although the amplitude of the synchronization signal is fixed as a condition for creating the graph of FIG. 3, as can be seen from the equation (7), the amplitude of the synchronization signal is fixed to an arbitrary value different from the above value. Can change the gradient. That is, the directivity of the beam can be adjusted by changing the phase difference between the oscillators of the one-dimensional oscillator array.

  In addition, the direction of the gradient of the oscillation phase characteristic 20 can be changed by changing the frequency of the synchronization signal applied to the oscillators 1A and 1B at both ends of the one-dimensional oscillator array. For example, when a synchronous signal of 8 GHz is injected into the oscillator 1A shown in FIG. 3 and a synchronous signal of 12 GHz is injected into the oscillator 1B, the first oscillator 1A (injection synchronous signal: 8 GHz) positioned at the end of the oscillator array It is also possible to change the slope so as to increase toward the oscillator 1B (injection locking signal: 12 GHz).

From the above results, the oscillation phase control method of the one-dimensional oscillator array according to the first embodiment of the present invention is the angular velocity displacement Δω (| Δω |> that is out of synchronization with the oscillators at both ends of the one-dimensional oscillator array. Fix to 1). At this time, the oscillation frequencies of the oscillators located at both ends of the one-dimensional oscillator array are fixed out of the range synchronized with the whole. Thereby, the phase of the signal radio wave radiated from each individual antenna can be changed only by adjusting the amplitude (A _inj ) of the synchronization signal, and the beam directivity can be controlled.

  Further, when synchronizing signals having different angular frequency displacements are given to the oscillators at both ends of the one-dimensional oscillator array, the direction of the beam can be adjusted by changing the direction of the displacement. Further, by changing the amplitude of the synchronization signal, the phase difference between the oscillators, that is, the directivity of the beam can be controlled.

  Hereinafter, the results (FIGS. 4 to 6) of the computer simulation of the operation of the oscillation phase control device of the one-dimensional oscillator array according to the present invention will be described using equations (5) to (7).

  First, the reason for performing this computer simulation will be described. As described above, Expression (5), Expression (6), and Expression (7) are described as being mathematically equivalent. However, a special mathematical approximation is used when transforming the theoretical formula (5) showing the operation of the oscillation phase control device of the one-dimensional oscillator array of this embodiment into the formula (6). Further, even when the equation (6) is transformed to the equation (7), the oscillation phase control device of the one-dimensional oscillator array of the present embodiment is in a steady state, and all the oscillators constituting this oscillation phase control device The equation is modified based on the assumption that the phase difference between the adjacent oscillators is always constant. Therefore, the results of the computer simulations of the equations (5), (6) and (7) are compared, and the theory showing the operation of the oscillation phase control device of the one-dimensional oscillator array of the present embodiment and the equation (6). It is necessary to verify the degree of mathematical equivalence of equation (5) and the reliability of equation (6) obtained from equation (5).

  At the same time, a computer simulation using the prior art (2) (see FIGS. 8 to 10) is also performed to clarify the difference between the prior art (2) and the proposed method. Further, in the oscillation phase control device of the one-dimensional oscillator array of the present embodiment, the change rate of the phase difference Δφ (beam directivity) with respect to the change of the amplitude of the synchronization signal is investigated to verify the practicality.

  4A and 4B are graphs showing the distribution of the oscillation phase difference in a one-dimensional oscillator array composed of 25 (N = 25) oscillators, and the vertical axis is adjacent to the target oscillator. The phase difference with the oscillator is represented, and the horizontal axis indicates the number of the target oscillator (1 to 25).

FIG. 4A shows the result of computer simulation using the equation (2) obtained by the prior art (2). Ω _m shown at the upper right in FIG. 4A is the angular velocity of the oscillation signal before the steady state in each oscillator of the one-dimensional oscillator array. Therefore, Δω / ω _m indicates that the larger the value, the larger the displacement between the angular velocity of the oscillation signal before the steady state and the angular velocity of the synchronization signal actually injected in each oscillator of the one-dimensional oscillator array. Yes. In this example, it is assumed that ω _m = 1 for simplicity. The simulation result when the value of [Delta] [omega / omega _m of 0.3,0.5,1.0, the phase difference characteristic 31 drawn based on the data points "●", and the drawing data points "×" based on A phase difference characteristic 32 and a phase difference characteristic 33 drawn based on the data point “*” are shown.

  A feature of the prior art (2) shown in FIG. 4A is that all the oscillators from the 0th to the 25th always show the same phase difference regardless of the displacement amount with the adjacent oscillators. It can also be confirmed that the phase difference between the adjacent oscillators increases as the difference in oscillation frequency between the oscillators located at both ends of the one-dimensional oscillator array and the internal oscillators increases.

FIG. 4B shows the result of the computer simulation using the equation (5) showing the operation of each oscillator of the oscillation phase control device of the one-dimensional oscillator array according to the present invention, where Δω / ω _m The data points obtained when the value is 5.0 are plotted. The data point “*” is obtained by performing an operation (snapshot) for obtaining a phase difference at an arbitrary moment 5000 times and taking an average value thereof. A phase difference characteristic 34 indicated by a solid line indicates a minimum phase difference of data points, and a phase difference characteristic 35 indicated by a broken line indicates a maximum phase difference of data points.

  What is characteristic in this computer simulation is that there is almost no difference between the maximum phase difference and the minimum phase difference (oscillator number i = 2 to 24), and there is a difference between the maximum phase difference and the minimum phase difference ( The oscillator number i = 1,25) exists. That is, the second to 24th oscillators located in the center of the one-dimensional oscillator array of the present embodiment are almost in a steady state and can control the oscillation phase, but the first one located at both ends of the one-dimensional oscillator array. Since the phase difference of the 25th oscillator varies with time, it can be confirmed that the phase difference cannot be controlled.

  In addition, since the phase difference obtained from the second to 24th oscillators located in the center of the one-dimensional oscillator array of the present embodiment is constant at the data point “*”, the second to 24th data points are also present. The oscillation phase of the oscillator can be controlled.

  Note that the second and 24th oscillators adjacent to both ends of the one-dimensional oscillator array are slightly affected by electromagnetic influences from the oscillators at both ends and the phase difference slightly varies. Therefore, when it is desired to control the directivity of the beam more accurately, the outputs obtained from the third to 23rd oscillators are excluded by excluding both ends and the adjacent oscillators among the oscillators constituting the one-dimensional oscillator array. May be supplied to the antenna as an effective output.

FIGS. 5A and 5B are graphs showing the relationship between the amplitude A _inj of the synchronization signal and the phase difference Δφ in the oscillation phase control apparatus of the one-dimensional oscillator array according to the present invention, and the vertical axis represents the relationship between the adjacent oscillators. The phase difference Δφ and the horizontal axis represent the normalized amplitude A _inj of the synchronization signal. The data points “●”, “x”, and “■” correspond to the computer simulation results using Equation (5), Equation (6), and Equation (7), respectively.

FIG. 5A is a graph showing the relationship between the amplitude A _inj of the synchronization signal and the phase difference Δφ when the angular velocity displacement Δω = 5.0 of the synchronization signal to be injected. A phase difference characteristic 41, a phase difference characteristic 42, and a phase difference characteristic 42 in which the computer simulation results using the expressions (5), (6), and (7) are drawn based on the data points “●”, “×”, and “■”. A phase difference characteristic 43 is shown. A characteristic feature of FIG. 5A is that the phase difference Δφ between the oscillators and the amplitude A _{inj of the} synchronization signal always have a substantially equal relationship regardless of the equation used in the computer simulation. Further, it can be confirmed that the phase difference Δφ can be controlled between 0 rad and about 1.2 rad only by changing the amplitude A _{inj of the} synchronization signal between 0 and 3, for example.

FIG. 5B is a graph showing the relationship between the amplitude A _inj of the synchronization signal and the phase difference Δφ when the angular velocity displacement Δω = 10.0 of the injected synchronization signal. A phase difference characteristic 44, a phase difference characteristic 45, and a phase difference characteristic 45 in which the computer simulation results using the expressions (5), (6), and (7) are drawn based on the data points “●”, “×”, and “■”. This is indicated by the phase difference characteristic 46. Similar to FIG. 5A, regardless of the equation used for the computer simulation, it can be confirmed that the phase difference Δφ between the oscillators and the amplitude A _{inj of the} synchronization signal always have substantially the same relationship. Further, when the amplitude A _{inj of the} synchronization signal is changed between 0 and 4.5, it can be confirmed that the phase difference Δφ can be controlled between 0 rad and about 1.2 rad.

From the graphs shown in FIGS. 5 (a) and 5 (b), it is understood that when the phase difference Δφ is changed, the amplitude A _{inj of the} synchronization signal must be changed more greatly as the value of the angular velocity displacement Δω is set larger. . That is, it can be understood that if the value of the angular velocity displacement Δω is set large, more precise control of the oscillation phase can be realized. It was also confirmed that when the value of the angular velocity displacement Δω is set to be small, the phase difference Δφ changes only by slightly changing the magnitude of the amplitude A _inj of the synchronization signal. If you want to control the directivity of the beam by finely changing the phase difference Δφ, increase the value of the displacement Δω of the angular velocity, and change the phase difference Δφ greatly using the synchronization signal of the same amplitude. If it is desired to control the angular velocity, the value of the angular velocity displacement Δω may be set appropriately according to the purpose of use, for example, by reducing the value of the angular velocity displacement Δω.

  5A and 5B, the theoretical formula (5) showing the operation of the one-dimensional oscillator array according to the present embodiment, the formula (6) obtained by approximating the formula (5), and the formula ( It was confirmed that the result of the computer simulation in each of the formulas (7) obtained directly from 6) has almost the same tendency.

  Furthermore, when the difference between the phase difference characteristics 41 to 43 in FIG. 5A and the difference between the phase difference characteristics 44 to 46 in FIG. 5B are compared, FIG. 5B is smaller. Therefore, it can be said that when the value of the angular velocity displacement Δω is set large, the degree of approximation of the equations (6) and (7) obtained by approximation is improved.

  By the way, the reason why the computer simulation results using the formulas (5), (6), and (7) do not completely match is that, as described above, the formulas (5) to (6) or It is thought that this is because mathematical approximation was used when transforming to (7). However, since the fluctuation characteristics (trends) of the computer simulation results coincide, it can be understood that the equations (5), (6), and (7) are mathematically equivalent. In other words, it was confirmed that the phase difference between the oscillators when the oscillation phase control device of the one-dimensional oscillator array of the present embodiment is in a steady state is expressed by Expression (7). That is, it has been proved that the oscillation phase control device of the one-dimensional oscillator array of the present embodiment can control the oscillation phase difference between the oscillators using a synchronization signal having an angular velocity that is out of synchronization.

  4 and FIG. 5, the oscillation phase control device of the one-dimensional oscillator array can control the oscillation phase with high accuracy except at least the oscillator at the end of the oscillator array. Furthermore, when the adjacent oscillator is removed, the oscillation phase can be controlled with higher accuracy.

  6 (a) and 6 (b) are graphs showing noise resistance in the oscillation phase control system of the present invention and the prior art. The vertical axis represents the phase difference between the target oscillator and the adjacent oscillator, and the horizontal axis represents the oscillator number (1 to 25). FIG. 6A shows noise resistance of the oscillation phase control method of the present invention, and FIG. 6B shows noise resistance of the conventional technique (2).

  As described above, it has been confirmed that the oscillation phase control apparatus for the one-dimensional oscillator array of the present invention does not stabilize the oscillation phases of the two oscillators at both ends of the one-dimensional oscillator array. Therefore, in order to investigate which of the oscillation phase control method of the present invention and the prior art (2) is resistant to noise, it is desirable to make a comparison with particular attention to the 3rd to 22nd oscillators.

  The data points plotted in the graph of FIG. 6A indicate the computer simulation results when white noise is added to each oscillator under the same conditions as in FIG. In this example, assuming that the range of the oscillation signal of each oscillator is 1, the white noise range is calculated as ± 0.2. The data point “*” is a plot of the average value of the phase difference after 5000 snapshots of each oscillator. As shown in FIG. 6A, in each oscillator in the steady state, the data point “*” is within a narrow range between the minimum phase difference characteristic 51 and the maximum phase difference characteristic 52.

  The data points plotted in the graph of FIG. 6B show the computer simulation results when white noise is added to each oscillator under the condition of Δω = 0.7 in FIG. Similarly to the above, when the range of the oscillation signal of each oscillator is 1, the calculation is performed assuming that the white noise range is ± 0.2. The data point “*” is a plot of the average value of the phase difference after 5000 snapshots of each oscillator. As shown in FIG. 6A, in each oscillator in the steady state, the data point “*” is within a narrow range between the minimum phase difference characteristic 53 and the maximum phase difference characteristic 54.

  As a result of the above comparison, the oscillation phase control device of the one-dimensional oscillator array of the present embodiment has a smaller phase difference between the minimum phase difference characteristic and the maximum phase difference characteristic than the prior art (2), and is equivalent or slightly superior. It can be confirmed that it has noise resistance.

  As described above, the oscillation phase control device of the one-dimensional oscillator array of this embodiment is based on the amplitudes of the synchronization signals injected into the oscillator 1A and the oscillator 1B located at both ends of the one-dimensional oscillator array (see Expression (7)). The phase difference between adjacent oscillators can be controlled with higher accuracy and easier than in the prior art (2). At this time, the oscillation frequencies of the oscillator 3A and the oscillator 3B for transmitting a synchronization signal to the oscillators located at both ends of the oscillator array may be appropriately set so that the oscillators located at both ends of the one-dimensional oscillator array are out of synchronization. . As a result, precise frequency setting as in the prior art (2) is not required. Further, since not only a sine wave but also a pulse wave and a rectangular wave can be used as the synchronization signal, it is possible to realize a more flexible oscillation phase control than the conventional technique (2).

  Next, an example of the second embodiment of the present invention will be described. The oscillation phase control method of the oscillator array according to the present invention can be applied not only to a one-dimensional oscillator array but also to a two-dimensional oscillator array as a configuration of the oscillator array.

  Hereinafter, the oscillation phase control apparatus of the two-dimensional oscillator array will be described with reference to FIG. FIG. 7 is a diagram showing an example of the configuration and operation of the oscillation phase control device of the two-dimensional oscillator array of the present invention. As shown in FIG. 7, the oscillation phase control device of the two-dimensional oscillator array of this embodiment has a configuration in which a plurality of oscillators 1 that generate oscillation signals of a predetermined frequency are arranged two-dimensionally and adjacent oscillators are connected. is there. For convenience of explanation, reference numerals 1A, 1B, 1C, and 1D are given to the four-dimensional oscillators of the two-dimensional oscillator array. Further, the oscillation phase control device of this two-dimensional oscillator array includes an oscillator 3A, an oscillator 3B, an oscillator 3C, and an oscillator 3D for injecting a synchronization signal into the square oscillator 1A, the oscillator 1B, the oscillator 1C, and the oscillator 1D. Is provided. The variable amplifiers 4A to 4D are connected between the four square oscillators 1A to 1D and the oscillators 3A to 3D for injecting synchronization signals. However, among the oscillators of the two-dimensional oscillator array shown in FIG. Further, although not shown, each oscillator constituting the two-dimensional oscillator array is connected to the antenna 2 shown in FIG.

  Note that the two-dimensional oscillator array of this embodiment shown in FIG. 7 is an example in which 25 oscillators 1 are used and arranged in a 5 × 5 matrix, but the number of oscillators used and the matrix configuration are shown in this example. Not limited to.

Next, the operation of the oscillation phase control device of the two-dimensional oscillator array shown in FIG. 7 will be described. First, the oscillation frequencies of the oscillators (1, 1A, 1B, 1C, 1D) constituting the two-dimensional oscillator array are all set to 10 GHz as an example. Further, in order to put the four-dimensional oscillators 1A to 1D of the two-dimensional oscillator array out of synchronization, the oscillation frequencies of the synchronization signals output from the oscillators 3A to 3D that output the synchronization signals are, for example, 10 GHz, 8 GHz, and 10 GHz, respectively. And 12 GHz. Then, similarly to the case of FIG. 1, the synchronizing signal A is supplied to each of the four-phase oscillators 1A to 1D of the two-dimensional oscillator array from the oscillators 3A to 3D via the appropriately set variable amplifiers 4A to 4D. _inj sin (Ω ± Δω) t [| Δω |> 1)] is injected.

  Thereafter, in a steady state, an oscillation phase gradient is formed from the lower one to the higher oscillation frequency of the oscillators 1A to 1D located at the four corners of the two-dimensional oscillator array. For example, in FIG. 7, the oscillation phase of the oscillator 1B is lower than that of the oscillator 1A. In addition, the oscillation phase of the oscillator 1D is higher than that of the oscillator 1A.

However, this gradient varies depending on the magnitude of the amplitude A _inj of the synchronizing signal to be injected, as in the case of the oscillation phase control device of the one-dimensional oscillator array. Regarding the oscillation phase of the oscillators constituting the two-dimensional oscillator array of the present embodiment, it can be confirmed that there is a region having a constant gradient in the two-dimensional oscillator array as in the oscillation phase characteristics 61 and 62 shown in FIG. . This means that even in the oscillation phase control device of the two-dimensional oscillator array of the present embodiment, the phase difference between the oscillators does not vary with time, and the magnitude of the amplitude A _inj of the synchronization signal is changed. Thus, the phase difference can be controlled.

  Further, when the oscillation phase control device value of this two-dimensional oscillation array is applied to the antenna system, the equiphase surface of the beam is represented by a two-dimensional plane. By changing the direction of the two-dimensional plane, the directivity of the beam can be controlled. The direction of the beam is a direction perpendicular to the two-dimensional equiphase plane, and the direction can be freely changed by changing the amplitude of the synchronization signal. For example, in the case of the example of FIG. 7, the beam before the synchronization signal injection is directly above the two-dimensional oscillator array, but in the steady state after the synchronization signal injection, the oscillator is connected to the straight line connecting the oscillator 1A and the oscillator 1C. Move to the 1B side.

  Thus, the oscillator array targeted by the oscillation phase control method of the oscillator array according to the present invention can be applied not only to a one-dimensional oscillator array but also to a two-dimensional oscillator array. The control method can be realized only by injecting a synchronizing signal into oscillators positioned at four corners of at least a two-dimensional oscillator array. In addition, the oscillation phase control device of the two-dimensional oscillator array has the same operations and effects as the oscillation phase control device of the one-dimensional oscillator array described above.

  The above-described embodiment is a preferred specific example of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the above description. Unless stated to the effect, the present invention is not limited to these forms. For example, the materials used and the numerical conditions such as the amount, processing time, and dimensions mentioned in the above description are only suitable examples, and the dimensions and shapes and arrangement relationships in the drawings used for the description are also schematic.

  In the above-described embodiment, the example in which the oscillation phase control device of the oscillator array of the present invention is applied to an antenna system (for example, a millimeter wave or a millimeter wave or more beam scanning circuit) has been described. It can also be applied to motion pattern generators.

It is a figure which shows the structural example of the oscillation phase control apparatus of the one-dimensional oscillator array which concerns on the 1st Embodiment of this invention. It is a figure which shows the example of an equivalent circuit of the component of the oscillation phase control apparatus of the one-dimensional oscillator array which concerns on the 1st Embodiment of this invention, (a) is an oscillator, (b) shows the coupling between oscillators. It is a figure where it uses for description of operation | movement of the oscillation phase control apparatus of the one-dimensional oscillator array which concerns on the 1st Embodiment of this invention. 4 is a graph showing an oscillation phase difference distribution of the one-dimensional oscillator array according to the first embodiment of the present invention, where (a) is based on the prior art and (b) is based on the method of the present invention. It is a figure which shows the relationship between the amplitude of an external synchronizing signal, and an oscillation phase difference in the oscillation phase control apparatus of the one-dimensional oscillator array which concerns on the 1st Embodiment of this invention. It is a figure which shows the noise tolerance of the oscillation phase difference distribution of the one-dimensional oscillator array which concerns on the 1st Embodiment of this invention. It is a figure which shows the structural example of the oscillation phase control apparatus of the two-dimensional oscillator array which concerns on the 2nd Embodiment of this invention. It is a figure where it uses for description of directivity control of the oscillation phase control apparatus of the conventional one-dimensional oscillator array. It is a block diagram of the oscillation phase control apparatus of the one-dimensional oscillator array of a conventional system (2). It is a figure which shows the pull-in area | region and non-synchronization area | region which concern on the oscillation phase control of the conventional oscillator array.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C, 1D ... Oscillator, 2 ... Antenna, 3A, 3B, 3C, 3D ... Oscillator for injection of synchronous signal, 4A, 4B, 4C, 4D ... Variable amplifier, 11 ... Capacitor, 12 ... Coil, DESCRIPTION OF SYMBOLS 13 ... Constant resistance element, 14 ... Nonlinear resistance element, 101 ... Oscillator, 102 ... Antenna, 103 ... Oscillation signal, 104 ... Equiphase phase

Claims (4)

An oscillation element array in which a plurality of oscillation elements capable of oscillating at substantially the same predetermined oscillation frequency are electromagnetically coupled in an array,
An external synchronization signal having a frequency greater than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized is injected into the oscillation element located at one end of the oscillation element array, and the oscillation element array Synchronization signal injection means for injecting an external synchronization signal having a frequency smaller than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized with respect to the oscillation element located at the other end of
A plurality of oscillating elements excluding the oscillating elements located at least at the end of the oscillating element array are effectively obtained to obtain an output.
An oscillation phase control device for an oscillation element array. An oscillation element located at the end of the oscillation element array with respect to the natural angular velocity of the effective oscillation element relative to the natural angular velocity of a plurality of effective oscillation elements (hereinafter referred to as “effective oscillation elements”) of the oscillation element array. When the amount of angular velocity displacement is ± Δω and the modulation signal applied to the oscillation element located at the end of the oscillation element array is A _inj sin (Ω ± Δω) t, the phase difference Δφ between adjacent effective oscillation elements is ,
Δφ = sin ⁻¹ (A _inj ² / 2Δω)
Where | Δω |> 1 is selected.
The oscillation phase control apparatus for an oscillation element array according to claim 1. The effective oscillation elements are individually connected to the antenna device, and the directivity of the antenna device is controlled based on the output of the effective oscillation element.
3. The oscillation phase control device for an oscillation element array according to claim 1, wherein A plurality of oscillating elements are electromagnetically coupled in an array to arrange an oscillating element array,
Select the oscillation frequency of each oscillation element to a predetermined frequency,
Injecting an external synchronization signal having a frequency larger than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized, to the oscillation element located at one end of the oscillation element array,
At the same time, for the oscillation element located at the other end of the oscillation element array, an external synchronization signal having a frequency smaller than the oscillation frequency and out of the frequency range in which each oscillation element is synchronized is injected,
A plurality of oscillation elements excluding the oscillation elements located at least at the ends of the oscillation element array are enabled to obtain an output,
An oscillation phase control method for an oscillation element array.

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