Array antenna device and calibration / monitoring program

Abstract

To facilitate estimating the absolute value of amplitude of a transmit signal of each individual antenna element in order to confirm performance as a transmitter, even when the number of antenna elements constituting an array antenna device is large.SOLUTION: The present disclosure is an array antenna device A comprising: a reflection coefficient acquisition unit 11 for acquiring the information of a coefficient of input-side reflection to a monitoring synthesis-distribution unit 9, with regard to a reflection signal from the monitoring synthesis-distribution unit 9 through reciprocation in respective monitoring paths 8-1 thru 8-N to the monitoring synthesis-distribution unit 9, when switched to a plurality of connection patterns, as a connection pattern of whether respective monitoring paths 8-1 thru 8-N are connected to short-circuiting, open-circuiting or termination; and an absolute amplitude value estimation unit 12 for estimating the absolute value of amplitude of transmit signals of respective antenna elements 6-1 thru 6-N, on the basis of the information of the reflection coefficient in the plurality of connection patterns.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a technique for calibrating an array antenna apparatus. [Background technology]

[0002] Array antenna devices control the phase and amplitude of each antenna element to form any beam pattern and are used in communications, radar, etc. Here, the array antenna device needs to monitor whether the phase and amplitude of each antenna element are at the intended values. Therefore, the array antenna device estimates the phase and amplitude of each antenna element and calibrates the phase and amplitude of each antenna element (see, for example, Patent Documents 1 and 2).

[0003] Each monitor path section is a feedback path for monitoring the transmission signal of each antenna element. The monitor combining / distributing section combines the monitor signals of the multiple monitor path sections. The antenna calibration section estimates the relative phase and amplitude of the transmission signal of each antenna element based on the combined signal of the monitor combining / distributing section, and calibrates each antenna element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-330660 [Patent Document 2] Japanese Patent Application Publication No. 6-069724 Summary of the Invention [Problem to be solved by the invention]

[0005] In other words, the array antenna apparatus only estimates the relative phase and amplitude of the transmission signal of each antenna element in order to calibrate each antenna element. Here, the array antenna apparatus needs to estimate the absolute value of the amplitude of the transmission signal of each antenna element in order to confirm its performance as a transmitter. This requires estimating the amount of loss in each monitor path, and after connecting a network analyzer to the input and output of each monitor path, it is necessary to estimate the transfer coefficient of each monitor path. Therefore, when there are a large number of antenna elements, it becomes difficult to estimate the absolute value of the amplitude of the transmission signal of each antenna element.

[0006] Therefore, in order to solve the above problem, an object of the present disclosure is to make it easy to estimate the absolute value of the amplitude of the transmission signal of each antenna element in order to confirm the performance as a transmitter, even when the number of antenna elements constituting an array antenna device is large. [Means for solving the problem]

[0007] To solve the above problem, each monitor switch unit connects one end of each monitor path unit on the antenna element side to either a short circuit, an open circuit, or a termination.When each monitor path unit is switched to a plurality of connection patterns as a connection pattern of whether it is connected to a short circuit, an open circuit, or a termination, the reflection coefficient acquisition unit acquires information on the reflection coefficient at the input side to the monitor signal combination unit for a reflected signal that passes from the monitor signal combination unit to the monitor signal combination unit after traveling back and forth through each monitor path unit.The amplitude absolute value estimator estimates a transfer coefficient of each monitor path unit, estimates the amount of loss of each monitor path unit, and estimates the absolute value of the amplitude of the transmission signal of each antenna element based on the information on the reflection coefficients in the plurality of connection patterns.

[0008] Specifically, the present disclosure provides an antenna array antenna including a plurality of antenna elements, monitor path sections for monitoring transmission signals of the respective antenna elements, a monitor signal synthesis section for synthesizing monitor signals of the plurality of monitor path sections, monitor switch sections for connecting one end of each of the monitor path sections on the antenna element side to either the antenna element side, short-circuit, open, or termination, and an antenna calibration section for estimating the relative phase and amplitude of the transmission signals of each of the antenna elements based on the synthesized signal of the monitor signal synthesis section when each of the monitor path sections is connected to the antenna element side, and calibrating each of the antenna elements. and a reflection coefficient acquisition unit that acquires information on the reflection coefficient at the input side to the monitor signal synthesis unit for a reflected signal that travels from the monitor signal synthesis unit to the monitor signal synthesis unit after traveling back and forth from the monitor signal synthesis unit to the monitor signal synthesis unit when a plurality of connection patterns are selected as the connection pattern for each of the monitor path sections to be connected to either a short circuit, an open circuit, or a termination; and an amplitude absolute value estimation unit that estimates a transfer coefficient of each of the monitor path sections based on the information on the reflection coefficient in the plurality of connection patterns, estimates an amount of loss in each of the monitor path sections, and estimates an absolute value of the amplitude of a transmission signal of each of the antenna elements.

[0009] With this configuration, it is only necessary to connect a network analyzer to the input side of the monitor signal combiner and obtain information on the reflection coefficients for multiple connection patterns, making it easy to estimate the absolute value of the amplitude of the transmission signal from each antenna element in order to confirm the transmitter performance, even when there are a large number of antenna elements.

[0010] The present disclosure also provides an array antenna device characterized in that the reflection coefficient acquisition unit acquires information on the reflection coefficients in the connection pattern in which one and the remaining monitor path sections are connected to an open circuit and a terminal, respectively, the connection pattern in which the one and the remaining monitor path sections are connected to a short circuit and a terminal, respectively, and the connection pattern in which the one and the remaining monitor path sections are all connected to terminals, and the amplitude absolute value estimation unit estimates a transfer coefficient of the one monitor path section based on the information on the reflection coefficients in the three connection patterns, estimates the amount of loss of the one monitor path section, and estimates the absolute value of the amplitude of the transmission signal of the one antenna element.

[0011] This configuration allows multiple connection patterns to be set simply, and the transfer coefficient of each monitor path section to be estimated simply. However, because multiple monitor paths are connected to the terminals, when the number of distributions in the monitor signal combiner is large, the reflection intensity in each connection pattern decreases, resulting in low measurement accuracy. Furthermore, while the transfer coefficient of each monitor path section is estimated based on the difference in reflection coefficients in multiple connection patterns, the multiple connection patterns differ by only one port, so the difference in reflection coefficients is small, resulting in low measurement accuracy.

[0012] The present disclosure also provides an array antenna device characterized in that the reflection coefficient acquisition unit acquires information on the reflection coefficients in the connection pattern in which one monitor path section and the remaining monitor path sections are all connected in an open state, the connection pattern in which the one monitor path section and the remaining monitor path sections are connected to a terminal and an open state, respectively, the connection pattern in which the one monitor path section and the remaining monitor path sections are all connected in a short state, and the connection pattern in which the one monitor path section and the remaining monitor path sections are connected to a terminal and a short state, respectively, and the amplitude absolute value estimation unit estimates a transfer coefficient of the one monitor path section based on the information on the reflection coefficients in four of the connection patterns, estimates the amount of loss of the one monitor path section, and estimates the absolute value of the amplitude of the transmission signal of the one antenna element.

[0013] With this configuration, because many monitor paths are connected to open or short circuits, the reflection intensity in each connection pattern is high, even when the monitor signal combiner has a large number of distributions. However, since the transfer coefficient of each monitor path is estimated based on the difference in reflection coefficients in multiple connection patterns, the multiple connection patterns differ by only one port, so the difference in reflection coefficients is small and the measurement accuracy is low. Furthermore, setting up multiple connection patterns becomes somewhat complicated, and estimating the transfer coefficient of each monitor path becomes somewhat complicated.

[0014] The present disclosure also provides an array antenna device characterized in that the reflection coefficient acquisition unit acquires information on the reflection coefficients in the connection pattern in which three of the monitor path sections and the remaining monitor path sections are all connected open, three connection patterns in which two of the three, the other one, and the remaining monitor path section are connected to a terminal, an open, and an open, respectively, the connection pattern in which the three of the monitor path sections and the remaining monitor path section are all connected short-circuited, and three connection patterns in which two of the three, the other one, and the remaining monitor path section are connected to a terminal, a short-circuited, and an short-circuited, respectively, and the amplitude absolute value estimation unit estimates transfer coefficients of the three monitor path sections based on the information on the reflection coefficients in the eight connection patterns, estimates the amount of loss of the three monitor path sections, and estimates the absolute values of the amplitudes of the transmission signals of the three antenna elements.

[0015] With this configuration, because many monitor paths are connected to open or short circuits, the reflection intensity in each connection pattern is high, even when the monitor signal combiner has a large number of distributions, resulting in high measurement accuracy. Furthermore, the transfer coefficient of each monitor path is estimated based on the difference in reflection coefficients in multiple connection patterns. Since the multiple connection patterns differ by as much as two ports, the difference in reflection coefficients is large, resulting in high measurement accuracy. However, setting up multiple connection patterns becomes somewhat complicated, and estimating the transfer coefficient of each monitor path becomes somewhat complicated.

[0016] The present disclosure also provides a calibration and monitoring program for an array antenna device that causes a computer to execute the processing steps of the antenna calibration unit, the reflection coefficient acquisition unit, and the amplitude absolute value estimation unit of the array antenna device described above.

[0017] With this configuration, it is only necessary to connect a network analyzer to the input side of the monitor signal combiner and obtain information on the reflection coefficients for multiple connection patterns, making it easy to estimate the absolute value of the amplitude of the transmission signal from each antenna element in order to confirm the transmitter performance, even when there are a large number of antenna elements. [Effects of the Invention]

[0018] In this way, the present disclosure makes it easy to estimate the absolute value of the amplitude of the transmission signal of each antenna element in order to confirm the performance as a transmitter, even when the array antenna device has a large number of antenna elements. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 10 is a diagram showing an array antenna device during amplitude and phase calibration of antenna elements according to the present disclosure. [Figure 2] 10 is a diagram illustrating an array antenna device when estimating the amount of loss in a monitor path section according to the present disclosure. FIG. [Figure 3] FIG. 10 is a diagram showing a procedure of calibration and monitoring processing of the array antenna apparatus of the present disclosure. [Figure 4] 5A and 5B are diagrams illustrating a specific example of a process for estimating a loss amount in a monitor path section in the first embodiment. [Figure 5] 4A and 4B are diagrams illustrating the principle of a process for estimating the amount of loss in a monitor path section in the first embodiment. [Figure 6] 10A and 10B are diagrams illustrating a specific example of a process for estimating the amount of loss in a monitor path section according to the second embodiment. [Figure 7] 13A and 13B are diagrams illustrating a specific example of a process for estimating the amount of loss in a monitor path section according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020]

[0023] The following embodiments of the present disclosure will be described with reference to the accompanying drawings. The embodiments described below are examples of implementation of the present disclosure, and the present disclosure is not limited to the following embodiments.

[0021] (Overview of the array antenna device of the present disclosure) An array antenna device according to the present disclosure when calibrating the amplitude and phase of the antenna elements is shown in Fig. 1. An array antenna device according to the present disclosure when estimating the amount of loss in the monitor path is shown in Fig. 2.

[0022] The array antenna device A includes a transmission / reception signal processing unit 1, a transmission / reception monitor switching unit 2, a transmission / reception combining / distributing unit 3, transmission / reception units 4-1,...,4-N, antenna switch units 5-1,...,5-N, antenna elements 6-1,...,6-N, monitor switch units 7-1,...,7-N, monitor path units 8-1,...,8-N, a monitor combining / distributing unit 9, an antenna calibration unit 10, a reflection coefficient acquisition unit 11, and an amplitude absolute value estimation unit 12, and is connected to a network analyzer N.

[0023] First, we will explain the operation of antenna elements 6-1, ..., 6-N during transmission. The transmission / reception signal processing unit 1 generates a transmission signal. The transmission / reception monitor switching unit 2 switches to transmission mode. The transmission / reception combining / distributing unit 3 distributes the transmission signal. The transmission / reception units 4-1, ..., 4-N control the phase and amplitude of the transmission signal and form any beam pattern. The antenna switch units 5-1, ..., 5-N connect the transmission / reception units 4-1, ..., 4-N to the antenna elements 6-1, ..., 6-N. The antenna elements 6-1, ..., 6-N output the transmission signal.

[0024] Next, the operation of the antenna elements 6-1, ..., 6-N during reception will be described. The antenna elements 6-1, ..., 6-N input received signals. The antenna switch units 5-1, ..., 5-N connect the antenna elements 6-1, ..., 6-N to the transmitter / receiver units 4-1, ..., 4-N. The transmitter / receiver units 4-1, ..., 4-N control the phase and amplitude of the received signals to form any beam pattern. The transmitter / receiver combining / distributing unit 3 combines the received signals. The transmitter / receiver monitor switching unit 2 switches to reception mode. The transmitter / receiver signal processing unit 1 processes the received signals.

[0025] The procedure for the calibration and monitoring process of the array antenna device of the present disclosure is shown in Fig. 3. The calibration and monitoring program for the array antenna device A shown in Fig. 3 is a program that causes a computer to function as an antenna calibration unit 10, a reflection coefficient acquisition unit 11, and an amplitude absolute value estimation unit 12.

[0026] First, referring to Figures 1 and 3, the amplitude and phase calibration of the antenna elements 6-1,...,6-N will be described. The monitor path sections 8-1,...,8-N are feedback paths for monitoring the transmission signals of the antenna elements 6-1,...,6-N. The antenna switch sections 5-1,...,5-N connect the transmission / reception sections 4-1,...,4-N to the monitor switch sections 7-1,...,7-N. The monitor switch sections 7-1,...,7-N connect one end of the monitor path sections 8-1,...,8-N that is on the antenna element 6-1,...,6-N side to the antenna element 6-1,...,6-N side, rather than short-circuiting, opening, or termination (step S1). The monitor combining and dividing section 9 combines the monitor signals of the monitor path sections 8-1,...,8-N.

[0027] The antenna calibration unit 10 estimates the relative phases and amplitudes of the transmission signals of the antenna elements 6-1, ..., 6-N based on the combined signal of the monitor combining and distributing unit 9, and calibrates the antenna elements 6-1, ..., 6-N (step S2, see Patent Documents 1 and 2, etc.).

[0028] Next, with reference to Figures 2 and 3, the estimation of the loss amount of the monitor path sections 8-1,...,8-N will be described. The network analyzer N is connected to the monitor combining / distributing section 9. The monitor switch sections 7-1,...,7-N connect one end of the monitor path sections 8-1,...,8-N on the antenna element 6-1,...,6-N side to either a short circuit, an open circuit, or a termination. Then, the connection pattern for the monitor path sections 8-1,...,8-N to be connected to either a short circuit, an open circuit, or a termination is switched between a plurality of connection patterns (step S3).

[0029] The reflection coefficient acquisition unit 11 acquires information on the reflection coefficient at the input side to the monitor combining / distributing unit 9 from the network analyzer N for the reflected signal that travels from the monitor combining / distributing unit 9 back and forth through the monitor path units 8-1, ..., 8-N to the monitor combining / distributing unit 9 (step S4).

[0030] The amplitude absolute value estimation unit 12 estimates the transfer coefficients of the monitor paths 8-1 to 8-N based on the information on the reflection coefficients in the multiple connection patterns, and estimates the amount of loss in the monitor paths 8-1 to 8-N. Then, based on the amount of loss in the monitor paths 8-1 to 8-N and the relative amplitudes of the transmission signals of the antenna elements 6-1 to 6-N, it estimates the absolute value of the amplitude of the transmission signals of the antenna elements 6-1 to 6-N (step S5).

[0031] In this way, it is only necessary to connect a network analyzer N to the input side of the monitor combining / distributing unit 9 and obtain information on the reflection coefficients for a plurality of connection patterns. Therefore, even when there are a large number of antenna elements, it is possible to easily estimate the absolute value of the amplitude of the transmission signal of the antenna elements in order to check the performance of the transmitter.

[0032] (Processing for Estimating Loss Amount in Monitor Path Section in First Embodiment) 4 and 5 show a specific example and principle of the process for estimating the amount of loss in the monitor path section in the first embodiment. In the first embodiment, the amount of loss in three monitor path sections 8-1, 8-2, and 8-3 is estimated, but as a modified example, the amount of loss in two or more monitor path sections 8-N may be estimated.

[0033] The reflection coefficient acquisition unit 11 acquires information on the reflection coefficients for the connection patterns shown in Figure 4 (step S4): (1) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are connected to an open circuit and a terminal, respectively; (2) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are connected to a short circuit and a terminal, respectively; and (3) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are all connected to terminals.

[0034] In FIG. 5, the input signal and the output signal are a1 and b1 on the network analyzer N side of the monitor combining / distributing unit 9. The input signal and the output signal are (b 1、1 , a 1、1 ), (b 2、1 , a 2、1 ), (b 3、1 , a 3、1 ) on the monitor switch units 7-1, 7-2, and 7-3 sides of the monitor path units 8-1, 8-2, and 8-3. The input and output signals are (a 1、2 , b 1、2 ), (a 2、2 , b 2、2 ), (a 3、2 , b 3、2 ) The S parameters of the monitor path sections 8-1, 8-2, and 8-3 are S1, S2, and S3. The reflection coefficients of the monitor switch sections 7-1, 7-2, and 7-3 are Γ1, Γ2, and Γ3. Under open conditions, Γ1, Γ2, and Γ3=1; under short-circuit conditions, Γ1, Γ2, and Γ3=-1; and under terminated conditions (impedance matching is achieved), Γ1, Γ2, and Γ3=0. The reflection coefficient on the input side to the monitor combining and dividing section 9 is Γ.

[0035] The S parameters of the ideal (lossless and equal distribution) monitor combining and dividing unit 9 are expressed by the following equation 1. Then, b1, b 1、1 , b 2、1 , b 3、1 is expressed by the following equation.

number

[0036] The S-parameter of the monitor path section 8-1 is expressed by the following equation 2. 1、1 , b 1、2 is expressed by the following equation 2. 1、12 =S 1、21 and a 1、2 =Γ1b 1、2 is.

number

[0037] a 1、1 , a 2、1 , a 3、1 is expressed as Equation 3 based on Equation 2.

number

[0038] Γ is expressed by Equation 4 based on Equation 1 and Equation 3.

number

[0039] In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are connected to an open circuit and a terminal, respectively, Γ=Γ ОLL is expressed as Equation 5 based on Equation 4. In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are short-circuited and terminated, respectively, Γ=Γ SLL is expressed as Equation 5 based on Equation 4. In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are all connected to the terminations, Γ=Γ LLL is expressed as Equation 5 based on Equation 4.

number

[0040] The amplitude absolute value estimation unit 12 estimates the transfer coefficient of the monitor path section 8-1 based on the information on the reflection coefficients in the three connection patterns, estimates the amount of loss in the monitor path section 8-1, and estimates the absolute value of the amplitude of the transmission signal of the antenna element 6-1 (step S5).

[0041] Gamma ОLL -Γ LLL is expressed by Equation 6 based on Equation 5 and is defined as A. SLL -Γ LLL is expressed by equation 6 based on equation 5 and is defined as B.

number

[0042] S 1、21 is expressed by the middle side of Equation 7 based on Equation 6. The combined S parameter S of the monitor path unit 8-1 and the monitor combining and distributing unit 9 is 1、21 is expressed by the right-hand side of equation 7.

number

[0043] In this way, multiple connection patterns can be set simply, and the transfer coefficient of each monitor path section can be estimated simply. However, because many monitor path sections are connected to the terminals, when the number of distributions in the monitor combining / distributing section 9 is large, the reflection intensity in each connection pattern decreases, resulting in low measurement accuracy. Furthermore, while the transfer coefficient of each monitor path section is estimated based on the difference in reflection coefficients in multiple connection patterns, the multiple connection patterns differ by only one port, so the difference in reflection coefficients is small, resulting in low measurement accuracy.

[0044] Specifically, if the number of distributions in the monitor combining / distributing unit 9 is 16 and the loss in each monitor path is 20 dB, the loss for one way will be 32 dB and the loss for round trip will be 64 dB. If the number of distributions in the monitor combining / distributing unit 9 is 3M (M is a natural number), the number of connection patterns will be 3×3M−1×(3M−1)=6M+1 patterns (Γ LLL The connection pattern needs to be measured only once.) The number of subtractions in equation 6 is 2 × 3M = 6M times.

[0045] (Processing for Estimating Loss Amount in Monitor Path Section in Second Embodiment) A specific example of the process for estimating the amount of loss in the monitor path sections in the second embodiment is shown in Fig. 6. In the second embodiment, the amount of loss in three monitor path sections 8-1, 8-2, and 8-3 is estimated, but as a modified example, the amount of loss in two or more monitor path sections 8-N may be estimated.

[0046] The reflection coefficient acquisition unit 11 acquires information on the reflection coefficients for the connection patterns shown in Figure 6 (step S4): (1) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are all connected open, (2) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are connected to a terminal and an open, respectively, (3) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are all connected short-circuited, and (4) a connection pattern in which the monitor path section 8-1 and the monitor path sections 8-2 and 8-3 are connected to a terminal and a short-circuit, respectively.

[0047] In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are all connected in an open state, Γ=Γ ООО is expressed by Equation 8 based on Equation 4. In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are connected to a terminal and an open circuit, respectively, Γ=Γ LОО is expressed by Equation 8 based on Equation 4. In a connection pattern in which the monitor path portion 8-1 and the monitor paths portions 8-2 and 8-3 are all short-circuited, Γ=ΓSSS is expressed by Equation 8 based on Equation 4. In a connection pattern in which the monitor path portion 8-1 and the monitor path portions 8-2 and 8-3 are connected to the termination and short circuit, respectively, Γ=Γ LSS is expressed by Equation 8 based on Equation 4.

number

[0048] The amplitude absolute value estimation unit 12 estimates the transfer coefficient of the monitor path section 8-1 based on the information on the reflection coefficients in the four connection patterns, estimates the amount of loss in the monitor path section 8-1, and estimates the absolute value of the amplitude of the transmission signal of the antenna element 6-1 (step S5).

[0049] Gamma ООО -Γ LОО is expressed by Equation 9 based on Equation 8 and is defined as A. SSS -Γ LSS is expressed by equation 9 based on equation 8 and is defined as B.

number

[0050] S 1、21 is expressed by the middle side of Equation 10 based on Equation 9. The combined S parameter S of the monitor path unit 8-1 and the monitor combining and distributing unit 9 is 1、21 is expressed by the right-hand side of equation 10.

number

[0051] In this way, because many monitor paths are connected to open or short circuits, the reflection intensity in each connection pattern is high and measurement accuracy is high, even when the number of distributions in the monitor combining / distributing unit 9 is large. However, since the transfer coefficient of each monitor path is estimated based on the difference in reflection coefficients in multiple connection patterns, the multiple connection patterns differ by only one port, so the difference in reflection coefficients is small and measurement accuracy is low. Furthermore, setting up multiple connection patterns becomes somewhat complicated, and estimating the transfer coefficient of each monitor path becomes somewhat complicated.

[0052] Specifically, if the number of distributions of the monitor combining and distributing unit 9 is 3M (M is a natural number), the number of connection patterns is 4×3M−2×(3M−1)=6M+2 patterns (Γ ООО , Γ SSS The connection pattern needs to be measured only once.) The number of subtractions in equation 9 is 2 × 3M = 6M times.

[0053] (Processing for Estimating Loss Amount in Monitor Path Section in Third Embodiment) A specific example of the process for estimating the amount of loss in the monitor path sections in the third embodiment is shown in Fig. 7. In the third embodiment, the amount of loss in four monitor path sections 8-1, 8-2, 8-3, and 8-4 is estimated, but as a modified example, the amount of loss in three or more monitor path sections 8-N may be estimated.

[0054] The reflection coefficient acquisition unit 11 acquires information on the reflection coefficients in the connection patterns shown in Figure 7 (step S4): (1) a connection pattern in which the monitor path sections 8-1, 8-2, 8-3, and the monitor path section 8-4 are all connected in the open state, (2) three connection patterns in which two of the monitor path sections 8-1, 8-2, and 8-3, the other monitor path section, and the monitor path section 8-4 are connected to a terminal, an open state, and an open state, respectively, (3) a connection pattern in which the monitor path sections 8-1, 8-2, 8-3, and the monitor path section 8-4 are all connected in the short state, and (4) three connection patterns in which two of the monitor path sections 8-1, 8-2, and 8-3, the other monitor path section, and the monitor path section 8-4 are connected to a terminal, a short state, and an short state, respectively.

[0055] In a connection pattern in which the monitor path portions 8-1, 8-2, 8-3, and 8-4 are all connected to the open circuit, Γ=Γ ОООО is expressed by Equation 11 based on Equation 4. In a connection pattern in which the monitor path portions 8-1, 8-2, 8-3, and 8-4 are connected to a terminal, an open circuit, and an open circuit, respectively, Γ=Γ LLОО is expressed by Equation 11 based on Equation 4. In a connection pattern in which the monitor path portions 8-2, 8-3, the monitor path portion 8-1, and the monitor path portion 8-4 are connected to a terminal, an open, and an open, respectively, Γ=Γ ОLLО is expressed by Equation 11 based on Equation 4. In a connection pattern in which the monitor path portions 8-1, 8-3, 8-2, and 8-4 are connected to a terminal, an open circuit, and an open circuit, respectively, Γ=Γ LОLО is expressed by Equation 11 based on Equation 4.

number

[0056] In a connection pattern in which the monitor path portions 8-1, 8-2, 8-3, and 8-4 are all short-circuited, Γ=Γ SSSS is expressed by Equation 12 based on Equation 4. In a connection pattern in which the monitor path portions 8-1, 8-2, 8-3, and 8-4 are connected to a terminal, a short circuit, and a short circuit, respectively, Γ=Γ LLSS is expressed by Equation 12 based on Equation 4. In a connection pattern in which the monitor path portions 8-2, 8-3, the monitor path portion 8-1, and the monitor path portion 8-4 are connected to a terminal, a short circuit, and a short circuit, respectively, Γ=Γ SLLS is expressed by Equation 12 based on Equation 4. In a connection pattern in which the monitor path portions 8-1, 8-3, 8-2, and 8-4 are connected to a terminal, a short circuit, and a short circuit, respectively, Γ=Γ LSLS is expressed by Equation 12 based on Equation 4.

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[0057] The amplitude absolute value estimation unit 12 estimates the transfer coefficients of the monitor path sections 8-1, 8-2, and 8-3 based on the information on the reflection coefficients in the eight connection patterns, estimates the loss amounts of the monitor path sections 8-1, 8-2, and 8-3, and estimates the absolute values of the amplitudes of the transmission signals of the antenna elements 6-1, 6-2, and 6-3 (step S5).

[0058] Gamma ОООО -Γ LLОО , Γ ОООО -Γ ОLLО and Γ ОООО -Γ LОLО is expressed by Equation 13 based on Equation 11. These include the S parameters of the two monitor path sections 8-N.

number

[0059] Gamma SSSS -Γ LLSS , Γ SSSS -Γ SLLS and Γ SSSS -Γ LSLS is expressed by Equation 14 based on Equation 12. These include the S parameters of the two monitor path sections 8-N.

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[0060] (Γ ОООО -Γ LLОО )-(Γ ОООО -Γ ОLLО )+(Γ ОООО -Γ LОLО ) is expressed by Equation 15 based on Equation 13, and defines A. (Γ SSSS -Γ LLSS )-(Γ SSSS -Γ SLLS )+(Γ SSSS -Γ LSLS ) is expressed by Equation 15 based on Equation 14, and defines B.

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[0061] S 1、21 is expressed by the middle side of Equation 16 based on Equation 15. The combined S parameter S of the monitor path unit 8-1 and the monitor combining and distributing unit 9 is 1、21 is expressed by the right-hand side of equation 16.

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[0062] (Γ ОООО -Γ LLОО )+(Γ ОООО -Γ ОLLО )-(Γ ОООО -Γ LОLО ) is expressed by Equation 17 based on Equation 13, and defines A'. (Γ SSSS -Γ LLSS )+(Γ SSSS -Γ SLLS )-(Γ SSSS -Γ LSLS ) is expressed by Equation 17 based on Equation 14, and defines B'.

number

[0063] S 2、21 is expressed by the middle part of Equation 18 based on Equation 17. The combined S parameter S of the monitor path unit 8-2 and the monitor combining and distributing unit 9 is 2、21 is expressed by the right-hand side of equation 18.

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[0064] -(Γ ОООО -Γ LLОО )+(Γ ОООО -Γ ОLLО )+(Γ ОООО -Γ LОLО ) is expressed by Equation 19 based on Equation 13, and defines A″. SSSS -ΓLLSS )+(Γ SSSS -Γ SLLS )+(Γ SSSS -Γ LSLS ) is expressed by Equation 19 based on Equation 14 and defines B″.

number

[0065] S 3、21 is expressed by the middle side of Equation 20 based on Equation 19. The combined S parameter S of the monitor path unit 8-3 and the monitor combining and distributing unit 9 is 3、21 is expressed by the right-hand side of number 20.

number

[0066] In this way, because many monitor paths are connected to open or short circuits, the reflection intensity in each connection pattern is high, and measurement accuracy is high, even when the number of distributions in the monitor combining and distribution unit 9 is large.Then, the transfer coefficient of each monitor path is estimated based on the difference in reflection coefficients in multiple connection patterns, and since the multiple connection patterns differ by as much as two ports, the difference in reflection coefficients is large, and measurement accuracy is high.However, setting up multiple connection patterns becomes somewhat complicated, and estimating the transfer coefficient of each monitor path becomes somewhat complicated.

[0067] Specifically, if the number of distributions of the monitor combining and distributing unit 9 is 3M (M is a natural number), the number of connection patterns will be 8×M−2×(M−1)=6M+2 patterns (Γ ОООО , Γ SSSS The connection pattern of needs to be measured only once.) The total number of subtractions and additions in Equation 13, Equation 14, Equation 15, Equation 17, and Equation 19 is (3×2+2×2×3)×M=18M times.

[0068] (Processing for Estimating Loss Amount in Monitor Path Section in Fourth Embodiment) The fourth embodiment is an embodiment that generalizes the first to third embodiments. Information on the reflection coefficient Γ (see Equation 21) in a plurality of connection patterns is calculated using the S parameter S of a plurality of monitor path sections 8-1, . . . , 8-N. 1、21 , S 1、22 ,···,S N、21 , S N、22 The S-parameters S of each monitor path 8-1, . . . , 8-N are 1、21 ,···,S N、21 Based on this, the amount of loss in each of the monitor path sections 8-1, . . . , 8-N and the absolute value of the amplitude of the transmission signal from each of the antenna elements 6-1, . . . , 6-N can be estimated.

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[0069] The array antenna device and calibration / monitoring program disclosed herein can easily estimate the absolute value of the amplitude of the transmission signal of each antenna element in order to confirm its performance as a transmitter, even when the array antenna device has a large number of antenna elements. [Explanation of symbols]

[0070] A: Array antenna device N: Network analyzer 1: Transmitting and receiving signal processing section 2: Transmit / Receive Monitor Switching Unit 3: Transmitting and receiving synthesis and distribution section 4-1, 4-N: Transmitter / receiver 5-1, 5-N: Antenna switch section 6-1, 6-N: Antenna elements 7-1, 7-N: Monitor switch section 8-1, 8-2, 8-3, 8-4, 8-N: Monitor path section 9: Monitor synthesis and distribution section 10: Antenna calibration section 11: Reflection coefficient acquisition unit 12: Absolute amplitude estimation unit

Claims

1. a plurality of antenna elements constituting an array antenna; a respective monitor path for monitoring a transmit signal of each of the antenna elements; a monitor signal synthesizing unit that synthesizes monitor signals from the plurality of monitor path units; each monitor switch unit that connects one end of each of the monitor path units on the antenna element side to one of the antenna element side, short-circuit, open, and termination; an antenna calibration unit that, when each of the monitor path units is connected to a corresponding one of the antenna elements, estimates a relative phase and amplitude of a transmission signal of each of the antenna elements based on a combined signal of the monitor signal combiner, and calibrates each of the antenna elements; a reflection coefficient acquisition unit that acquires information on a reflection coefficient at an input side to the monitor signal synthesis unit with respect to a reflected signal that travels from the monitor signal synthesis unit to the monitor signal synthesis unit and back again to the monitor signal synthesis unit when a plurality of connection patterns are selected as connection patterns for each of the monitor path units to be connected to either a short circuit, an open circuit, or a termination; an amplitude absolute value estimation unit that estimates a transfer coefficient of each of the monitor path sections based on information on the reflection coefficients in the plurality of connection patterns, estimates an amount of loss in each of the monitor path sections, and estimates an absolute value of an amplitude of a transmission signal of each of the antenna elements; An array antenna device comprising:

2. the reflection coefficient acquisition unit acquires information on the reflection coefficients in the connection pattern in which one and the remaining monitor path sections are connected to an open circuit and a terminal, respectively, the connection pattern in which the one and the remaining monitor path sections are connected to a short circuit and a terminal, respectively, and the connection pattern in which the one and the remaining monitor path sections are all connected to terminals; The amplitude absolute value estimation unit estimates a transfer coefficient of the one monitor path section based on information on the reflection coefficients in the three connection patterns, estimates an amount of loss of the one monitor path section, and estimates an absolute value of the amplitude of a transmission signal of the one antenna element.

2. The array antenna device according to claim 1, wherein:

3. the reflection coefficient acquisition unit acquires information on the reflection coefficients in the connection pattern in which one and the remaining monitor path sections are all connected to an open circuit, the connection pattern in which the one and the remaining monitor path sections are connected to a terminal and an open circuit, respectively, the connection pattern in which the one and the remaining monitor path sections are all connected to a short circuit, and the connection pattern in which the one and the remaining monitor path sections are connected to a terminal and a short circuit, respectively; The amplitude absolute value estimation unit estimates a transfer coefficient of the one monitor path section based on information on the reflection coefficients in the four connection patterns, estimates an amount of loss of the one monitor path section, and estimates an absolute value of the amplitude of a transmission signal of the one antenna element.

2. The array antenna device according to claim 1, wherein:

4. the reflection coefficient acquisition unit acquires information on the reflection coefficients for the connection pattern in which three of the monitor path sections and the remaining monitor path section are all connected in an open state, three connection patterns in which two of the three, the remaining one, and the remaining monitor path section are connected in a terminal state, an open state, and an open state, respectively; the connection pattern in which the three of the monitor path sections and the remaining monitor path section are all connected in a short state, and three connection patterns in which two of the three, the remaining one, and the remaining monitor path section are connected in a terminal state, a short state, and an short state, respectively; The amplitude absolute value estimation unit estimates transfer coefficients of the three monitor path sections based on information on the reflection coefficients in the eight connection patterns, estimates loss amounts of the three monitor path sections, and estimates absolute values of amplitudes of transmission signals of the three antenna elements.

2. The array antenna device according to claim 1, wherein:

5. 5. A calibration and monitoring program for an array antenna device, causing a computer to execute each processing step of the antenna calibration unit, the reflection coefficient acquisition unit, and the amplitude absolute value estimation unit of the array antenna device according to claim 1.

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