JP2013034129A - Inter-branch correction device of phased array antenna and inter-branch correction method of phased array antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-branch correction device of a phased array antenna capable of precisely correcting phase errors in high frequency signals among branches provided corresponding to each antenna included in the phased array antenna without increasing the circuit size.SOLUTION: The inter-branch correction device of the phased array antenna has plural branches including a modulating section, a delay section, a mixer section and an antenna. The inter-branch correction device further includes: a frequency conversion section that converts the frequency on the basis of two high frequency signals from neighboring branches; a filter section that extracts a DC component on the basis of an output signal from the frequency conversion section; and a delay control section that determines a predetermined phase delay amount in the delay section of a branch on the basis of the DC component extracted by the filter section. The delay control section causes any one of the delay sections of neighboring branches to delay the phase of a transmission signal modulated by any one of the branches equivalent to the determined predetermined delay amount.

Description

  The present invention relates to an inter-branch correction device for a phased array antenna and an inter-branch correction method for a phased array antenna that correct an error between high-frequency signals in each branch system provided corresponding to a plurality of antennas constituting the phased array antenna. .

  Recently, the phased array technology is widely used not only in the sensing technology field for detecting an object (target) but also in the communication technology field. In phased array technology, a phased array antenna is constructed using multiple antenna elements, and the phase component between signals in each branch system (hereinafter referred to as “branch”) provided for each antenna element is controlled with high accuracy. To do. In the phased array technique, desired directivity can be formed by controlling the phase component between high-frequency signals in each branch with high accuracy.

  In the phased array technique, in order to form the directivity with respect to the transmission direction of a desired transmission signal or the arrival direction of a reception signal with high accuracy, it is necessary to correct a phase deviation between high-frequency signals in adjacent branches. For example, Patent Literature 1 is known as a method for correcting a phase deviation of a signal.

  The array antenna transmission apparatus of Patent Literature 1 includes an array antenna configured using a plurality of antenna elements, and divides the bandwidth of a transmission signal into a plurality of blocks. The array antenna transmission apparatus calculates a common calibration value for the transmission signals in the same block by averaging using the transmission signals in the divided blocks. The array antenna transmission apparatus corrects a phase deviation generated between branches of the transmission circuit provided corresponding to each of the plurality of antenna elements based on the calculated calibration value. As a result, the array antenna transmission apparatus can simplify the apparatus configuration and realize highly accurate calibration.

JP 2005-348236 A

  However, when a high-frequency signal that can be detected with high accuracy (for example, a millimeter wave) is used in Patent Document 1 described above, the high-frequency signal is fed back via a switch element for switching a branch to be measured. The phase of the high frequency signal changes greatly. For this reason, in order to use a high frequency signal (for example, millimeter wave) for the phased array technique described above, it is difficult to accurately correct the phase deviation between the high frequency signals in each branch.

  In order to correct the phase deviation between high-frequency signals (for example, millimeter waves) in each adjacent branch with high accuracy, a configuration of Patent Document 1 is assumed in which no switching element is provided in a high-frequency circuit unit that inputs a high-frequency signal. . In the N branch (for example, N = 3) transmission device 100z shown in FIG. 11, a loopback path for inputting N high frequency signals from each branch to the switch 34 and N downmixing mixers 31 to 31. 33. Thereby, the phase deviation which arises between high frequency signals (for example, millimeter wave) in each adjacent branch can be corrected with high accuracy. FIG. 11 is a block diagram illustrating an internal configuration of an N-branch transmission apparatus including N high-frequency signal loopback paths and N down-conversion mixers.

  However, in the configuration of FIG. 11, many mixers 8, 14, 20, 31 to 33, a drive buffer for generating a local signal Lo used in each mixer, and a signal down-converted in each mixer 31 to 33. An FFT (Fast Fourier Transform) processing unit 36 for analyzing the above is required. Therefore, the circuit scale of the transmission device 100z is increased, and it is difficult to reduce power consumption in the entire circuit.

  The present invention has been made in view of the above-described conventional circumstances, and without increasing the circuit scale, the phase between the high-frequency signals in each branch provided corresponding to each antenna constituting the phased array antenna. It is an object of the present invention to provide an inter-branch correction device for a phased array antenna and an inter-branch correction method for a phased array antenna that correct an error with high accuracy.

  The present invention includes a modulation unit that modulates a baseband transmission signal, a delay unit that delays a phase of the modulated transmission signal, a mixer unit that converts the delayed transmission signal into a high-frequency signal, An inter-branch correction device for a phased array antenna having a plurality of branches including an antenna for transmitting a high-frequency signal, the frequency conversion unit converting the frequency based on the two high-frequency signals output from each of the adjacent branches; A filter unit that extracts a DC component based on an output signal from the frequency converter, and a predetermined phase delay amount in the delay unit of the branch is determined based on the DC component extracted by the filter unit A delay control unit, wherein the delay control unit is connected to any one of the delay units in each of the adjacent branches. The phase of the modulated said transmitted signal in inches, the determined delays as the predetermined delay amount.

  The present invention also provides a modulation unit that modulates a baseband transmission signal, a delay unit that delays the phase of the modulated transmission signal, and a mixer unit that converts the delayed transmission signal into a high-frequency signal. An inter-branch correction method for an inter-branch correction apparatus for a phased array antenna having a plurality of branches including an antenna that transmits the high-frequency signal, based on two high-frequency signals output from each of the adjacent branches A step of frequency conversion; a step of extracting a DC component based on the output signal output by the frequency conversion; and a predetermined phase delay amount in the delay unit of the branch based on the extracted DC component Determining, in any one of the adjacent branches, in any one of the delay units, in any one of the branches. The phase of the modulated said transmitted signal Te, and a step of said determined the predetermined delay amount delays the.

  According to the present invention, a phase error between high frequency signals in each branch provided corresponding to each antenna constituting a phased array antenna can be corrected with high accuracy without increasing the circuit scale.

The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 1st Embodiment The graph which shows the simulation result of the relationship between the phase delay amount in the delay device of the 1st branch, and the output signal of LPF The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 2nd Embodiment The graph which shows the simulation result of the relationship between the phase delay amount in the delay device of the 1st branch, and the output signal of LPF The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 3rd Embodiment. Explanatory drawing showing an example of a phase adjustment table The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 4th Embodiment The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 5th Embodiment The block diagram showing the internal structure of the correction apparatus between branches of the phased array antenna of 6th Embodiment A block diagram showing a configuration example in which a non-linear element is used instead of a mixer as a circuit element for inputting a high-frequency signal from each branch. Block diagram showing the internal configuration of an N-branch transmission apparatus including N high-frequency signal loopback paths and N down-conversion mixers

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an inter-branch correction device for a phased array antenna and an inter-branch correction method for a phased array antenna according to the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram illustrating an internal configuration of an inter-branch correction apparatus 100 for a phased array antenna according to the first embodiment. First, the configuration of each part of the inter-branch correction apparatus 100 for the phased array antenna will be described.

  A phased array antenna inter-branch correction apparatus 100 includes a first branch A, a second branch B, a third branch C, and a mixer (MIX: Mixer), which are a plurality (N) of transmission branch systems (hereinafter referred to as “branches”). 9, LPF (Low Pass Filter) 10, mixer 15, LPF 16, switch (SW) 21, ADC (Analog Digital Converter) 22, delay control unit 23, and local signal generation unit LoGen.

  In the inter-branch correction apparatus for phased array antennas of the following embodiments, the configuration with the parameter N = 3 is shown, but the parameter N may be a natural number of 2 or more, and the same applies to the other embodiments. is there.

  The first branch A includes a modulation unit 5, a delay unit 6 as a delay unit, a DAC (Digital Analog Converter) 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch B includes a modulation unit 11, a delay unit 12 as a delay unit, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch C includes a modulation unit 17, a delay unit 18 as a delay unit, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  In the following embodiments, the configuration and operation of each branch (the first branch A, the second branch B, and the third branch C) are the same, and therefore the first branch A will be described as an example.

  Next, the operation of each part of the inter-branch correction apparatus 100 for the phased array antenna will be described.

  The inter-branch correction apparatus 10 for the phased array antenna is configured to delay the phase error generated between the two high-frequency signals RF1 and RF2 output from the first branch A and the second branch B based on the output signal of the LPF 10. Determine in The inter-branch correction device 10 of the phased array antenna performs phase control of the transmission signal as phase control in the baseband transmission signal of the first branch A or the second branch B based on the phase error determined by the delay control unit 23. Delay. Thereby, the inter-branch correction apparatus 100 for the phased array antenna can cancel the phase error between the first branch A and the second branch B.

  The inter-branch correction device 10 of the phased array antenna cancels the phase error between the first branch A and the second branch B, and similarly, the two high-frequency signals RF2 output from the second branch B and the third branch C , RF3, the delay controller 23 determines the phase error based on the output signal of the LPF 16. The inter-branch correction apparatus 100 of the phased array antenna delays the phase of the transmission signal as phase control in the baseband signal of the second branch B or the third branch C based on the phase error determined by the delay control unit 23. . Thereby, the inter-branch correction apparatus 100 of the phased array antenna can cancel the phase error between the second branch B and the third branch C.

  The delay control as the phase control of the baseband transmission signal in the first branch A or the second branch B is the same as the delay control as the phase control of the baseband transmission signal in the second branch B or the third branch C. Is the action. In each of the following embodiments, delay control as phase control of the baseband transmission signal in the first branch A or the second branch B will be described, and the phase of the baseband transmission signal in the second branch B or the third branch C will be described. Description of delay control as control is omitted.

  The modulation unit 5 digitally modulates, for example, a baseband transmission signal input as a test signal for phase delay control, and as a result of the digital modulation, an in-phase signal (I signal) of an in-phase component and an orthogonal signal of a quadrature component A baseband transmission signal configured using (Q signal) is output to the delay unit 6.

  The delay unit 6 as a delay unit is configured by using one or a plurality of flip-flops or FIR (Finite Impulse Response) filters. When the delay unit 6 is configured using an FIR filter, the delay unit 6 can control the delay with higher accuracy than when configured using one or a plurality of flip-flops.

  The delay unit 6 receives the baseband transmission signal output from the modulation unit 5 and further sets the phase of the input transmission signal by a predetermined amount based on a delay control instruction output from the delay control unit 23 described later. It will be delayed. Note that the delay control instruction includes a delay amount of the phase delayed in the delay unit 6. The delay device 6 outputs the transmission signal with the phase delayed to the DAC 7.

  The DAC 7 receives the transmission signal output from the delay device 6 and converts the digital transmission signal into an analog transmission signal. The DAC 7 outputs an analog transmission signal to the mixer 8.

  The mixer 8 serving as a mixer unit inputs an analog transmission signal output from the DAC 7 and up-converts the input transmission signal based on the local signal Lo supplied from the local signal generation unit LoGen. The mixer 8 outputs the high-frequency signal RF1 (for example, millimeter wave) generated by the up-conversion to the antenna Ant1 and the mixer 9, respectively. The high-frequency signal RF1 output from the mixer 8 is transmitted via the antenna Ant1.

  The mixer 9 as a frequency conversion unit receives the high-frequency signal RF1 output from the mixer 8 of the first branch A and the high-frequency signal RF2 output similarly from the mixer 14 of the second branch B. The mixer 9 multiplies the input two high-frequency signals RF1 and RF2, and outputs an output signal Y of the multiplication process to the LPF 10.

  The multiplication process in the mixer 9 will be described using mathematical expressions. The two high-frequency signals RF1 and RF2 are expressed by Equation (1) and Equation (2). The baseband transmission signal output from the modulation unit (modulation unit 5, modulation unit 11, modulation unit 17) of each branch (first branch A, second branch B, third branch C) is an angular velocity ω. It is a CW (Continuous Wave) wave of the same phase.

  In Equation (1), the parameter X is a variable from −180 ° [degree] to + 180 ° [degree], and is a phase delay amount in the delay device 6 of the first branch A. In the present embodiment, the delay control unit 23 delays the phase of the baseband transmission signal in the delay unit 6 among the delay unit 6 in the first branch A and the delay unit 12 in the second branch B. However, the delay control unit 23 may delay the phase of the baseband transmission signal in the delay unit 12.

  In Expression (2), the parameter φ is a phase generated between the two high-frequency signals RF1 and RF2 due to the up-conversion of the mixers 8 and 14 in the adjacent branches (first branch A and second branch B). Represents an error.

  The mixer 9 multiplies the two high-frequency signals RF1 and RF2, and outputs the multiplication processing result Y to the LPF 10 (see Expression (3)). In Equation (3), the parameter Y represents the result of multiplication processing of the two high-frequency signals RF1 and RF2. In Expression (3), the multiplication processing result Y of the mixer 9 includes a signal of a sum component of a high-frequency component that is twice the angular velocity ω and a DC component that does not depend on the angular velocity ω.

  The LPF 10 removes high-frequency component signals exceeding a predetermined cutoff frequency. The LPF 10 removes the first term component of the mathematical formula (3) corresponding to the high frequency component from the multiplication processing result Y (see the mathematical formula (3)) of the mixer 9, and switches the signal Z of the DC component independent of the angular velocity ω to the switch 21. (See equation (4)). That is, in the inter-branch correction apparatus 100 of the phased array antenna, the output signal Z of the LPF 10 becomes a low-frequency fixed DC component from which a high-frequency component (for example, millimeter wave) has been removed.

  The local signal generation unit LoGen generates a local signal Lo for up-conversion in the mixer (mixer 8, mixer 14, and mixer 20) of each branch (first branch A, second branch B, and third branch C). The local signal generation unit LoGen supplies the generated local signal Lo to the mixer 8, the mixer 14, and the mixer 20 of each branch (first branch A, second branch B, and third branch C).

  The switch 21 switches the connection between the LPF 10 and the ADC 22 or between the LPF 16 and the ADC 22 in accordance with a switching control signal output from a switch control unit (not shown). The switch 21 connects the LPF 10 and the ADC 22 while delaying the phase of the baseband transmission signal of the first branch A or the second branch B. As a result, the output signal Z of the LPF 10 is input to the ADC 22.

  The switch 21 connects the LPF 16 and the ADC 22 while delaying the phase of the baseband transmission signal of the second branch B or the third branch C. As a result, the output signal of the LPF 16 is input to the ADC 22.

  The ADC 22 inputs the output signal Z of the LPF 10 through the switch 21. The ADC 22 converts the analog output signal Z from the input LPF 10 into a digital output signal. The ADC 22 outputs a digital output signal to the delay control unit 23.

  Based on the output signal Z (DC component) of the LPF 10 converted by the ADC 22, the delay control unit 23 performs the phase delay of the baseband transmission signal in the delay unit 6 of the first branch A or the delay unit 12 of the second branch B. Determine the amount. In this embodiment, the inter-branch correction apparatus 100 for the phased array antenna delays the phase of the baseband transmission signal in the delay device 6 of the first branch A. Therefore, the delay control unit 23 determines the phase delay amount of the baseband transmission signal in the delay unit 6 of the first branch A based on the output signal Z of the LPF 10 converted by the ADC 22.

  The delay control unit 23 outputs a delay control instruction including the determined phase delay amount to any one of the delay unit 6 or the delay unit 12 in the adjacent first branch A and second branch B. That is, the delay control unit 23 sends the phase of the baseband transmission signal modulated in any branch to one of the delay units 6 or 12 of the adjacent first branch A and second branch B. The determined phase delay amount is delayed.

  In this embodiment, the delay control unit 23 sends the phase of the baseband transmission signal modulated by the modulation unit 5 to the delay unit 6 of the first branch A of the adjacent first branch A and second branch B. The determined phase delay amount is delayed.

  The determination of the phase delay amount in the delay control unit 23 will be described with reference to FIG. FIG. 2 is a graph showing a simulation result of the relationship between the phase delay amount in the delay device 6 of the first branch A and the output signal Z of the LPF 10.

  In FIG. 2, the horizontal axis represents the parameter X [degree] (see Equation (1)), and the vertical axis represents the output signal Z (DC component) of the LPF 10. FIG. 2 shows a simulation result when the phase error φ is 5 ° [degrees] between the high-frequency signal RF1 from the first branch A and the high-frequency signal RF2 from the second branch B. In FIG. 2, the output signal Z of the LPF 10 has a maximum value when the parameter X is changed and the phase component of the equation (4) becomes zero, that is, X (= φ) = 5 ° [degree].

  The delay control unit 23 uses the parameter X (5 ° [degree] in FIG. 2) when the output signal Z of the LPF 10 becomes the maximum value in FIG. 2 as the phase delay amount of the baseband transmission signal in the delay unit 6. Judge as. The delay control unit 23 determines the phase delay of the baseband transmission signal modulated by the modulation unit 5 to the delay unit 6 of the first branch A out of the adjacent first branch A and second branch B. Delay by an amount (5 [deg.]). The delay control unit 23 does not delay the phase of the baseband transmission signal modulated by the modulation unit 11 in the delay unit 12 of the second branch B.

  Further, the delay control unit 23 determines the phase of the baseband transmission signal modulated by the modulation unit 11 to the delay unit 12 of the second branch B out of the adjacent first branch A and second branch B. You may delay by the amount of phase delays (-5 degree [degree]) equivalent to the reverse phase part of phase delay amount. The delay control unit 23 does not cause the delay unit 6 of the first branch A to delay the phase of the baseband transmission signal modulated by the modulation unit 5.

  As described above, the inter-branch correction apparatus 100 for the phased array antenna is configured so that the delay unit 6 or the delay is based on the output signals of the LPF 10 in the two high-frequency signals RF1 and RF2 output from the adjacent first branch A and second branch B. The phase delay amount in the device 12 is determined. Further, the inter-branch correction apparatus 100 of the phased array antenna determines the phase of the baseband transmission signal modulated in each branch corresponding to the delay unit 6 or the delay unit 12 to the delay unit 6 or the delay unit 12. Delay by the amount of phase delay.

  Thereby, according to the inter-branch correction apparatus 100 of the phased array antenna, the phase error between the high-frequency signals in each branch provided corresponding to each antenna constituting the phased array antenna can be corrected with high accuracy. In addition, the inter-branch correction apparatus 100 for the phased array antenna does not require the configuration of the FFT processing unit 36 and can further reduce the number of mixers, compared to the conventional configuration shown in FIG. Thereby, the inter-branch correction apparatus 100 for the phased array antenna can effectively reduce the power consumption in the entire circuit of the inter-branch correction apparatus 100 for the phased array antenna without increasing the circuit scale.

(Second Embodiment)
In the second embodiment, a method for highly accurate detection of a phase difference without using a high resolution ADC will be described.

  In the configuration of the first embodiment, the phases between two high-frequency signals output from adjacent branches do not match. For example, when the parameter X = 0 ° [degree] and the parameter φ = 1 ° [degree], the phase An error of 1 ° [degree] occurs. In FIG. 2, the value of the output signal Z of the LPF 10 is a value of about 0.015%, and the value of the output signal Z of each LPF 10 corresponding to the parameter X = 0 ° [degree] and the parameter X = 1 ° [degree]. Is the difference.

  In the determination by the delay control unit 23, an error may occur in the determination of the maximum value of the output signal Z of the LPF 10. Accordingly, the ADC 22 having the configuration of the first embodiment needs to perform AD (Analog Digital) conversion of the output signal Z of the LPF 10 with high accuracy in order to increase the detection accuracy of the maximum value of the output signal Z of the LPF 10.

  On the other hand, for example, when the parameter X = 90 ° [degree] and the parameter φ = 91 [degree], the same phase error = 1 ° [degree] is generated. In FIG. 2, the value of the output signal Z (DC component) of the LPF 10 is a parameter X = 90 ° [degree], and the value of the output signal Z of each LPF 10 corresponding to the parameter X = 91 ° [degree] is about 1.745. There is a difference in the value of%.

  Therefore, the detection accuracy of the ADC 22 having the same bit resolution (for example, 7 bits) is about 100 times higher in the vicinity of the parameter X = 90 ° [degree] than in the vicinity of the parameter X = 0 ° [degree]. That is, the delay control unit 23 determines the maximum value of the output signal Z of the LPF 10, and sets the zero value of the output signal Z to which a phase error φ in the vicinity of 90 ° [degree] is given in advance between two high-frequency signals. It is possible to determine the phase error more easily and with higher accuracy. The phase error near 90 ° [degree] is, for example, a range of 90 ° [degree] ± 5 ° [degree].

  In the second embodiment, when the phase error between two high-frequency signals is in the vicinity of 0 ° [degree] (for example, 0 ° [degree] to 10 ° [degree]), modulation of any of the adjacent branches is performed. The I signal and Q signal of the baseband transmission signal modulated in the unit are switched. By exchanging the I signal and the Q signal, the phase error between two high-frequency signals output from adjacent branches becomes (90 ° [degree] + φ). Thereby, the ADC 22 can determine the output signal Z of the LPF 10 with high accuracy in the vicinity of the parameter φ = 90 ° [degree] where the detection accuracy becomes higher.

  FIG. 3 is a block diagram illustrating an internal configuration of the inter-branch correction apparatus 100a for the phased array antenna according to the second embodiment. Since the same reference numerals are used for the components that operate in the same manner as in the first embodiment, description thereof will be omitted, and different contents will be described.

  A phased array antenna inter-branch correction apparatus 100a includes a plurality of (N) branches, a first branch Aa, a second branch Ba, a third branch Ca, a mixer 9a, an LPF 10a, a mixer 15a, an LPF 16a, a switch 21, an ADC 22, This configuration includes a delay control unit 23a and a local signal generation unit LoGena.

  The first branch Aa includes a modulation unit 5, a replacement unit 24, a delay unit 6a as a delay unit, a DAC 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch Ba is configured to include a modulation unit 11, a replacement unit 25, a delay unit 12a as a delay unit, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch Ca includes a modulation unit 17, a replacement unit 26, a delay unit 18a as a delay unit, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  The replacement unit 24 or the replacement unit 25 replaces each component of the I signal and the Q signal of the baseband transmission signal output from the modulation unit 5 or the modulation unit 11. In the present embodiment, while canceling the phase error between the first branch Aa and the second branch Ba, the replacement unit 24 performs each of the I signal and the Q signal of the baseband transmission signal output from the modulation unit 5. Replace the ingredients. Furthermore, the replacement unit 25 does not replace each component of the I signal and the Q signal of the baseband transmission signal output from the modulation unit 11.

  However, when the replacement unit 25 replaces each component of the I signal and the Q signal of the baseband transmission signal output from the modulation unit 11, the replacement unit 24 replaces the I of the baseband transmission signal output from the modulation unit 5. The respective components of the signal and the Q signal are not interchanged.

  The replacement unit 24 receives the baseband transmission signal output from the modulation unit 5, and further replaces each component of the input I signal and Q signal of the transmission signal. The replacement unit 24 outputs the baseband transmission signal in which the components of the I signal and the Q signal are switched to the delay unit 6a.

  The replacement unit 25 receives the baseband transmission signal output from the modulation unit 11 and further replaces each component of the input I signal and Q signal of the transmission signal. The replacement unit 25 outputs a baseband transmission signal in which the components of the I signal and the Q signal are switched to the delay unit 12a.

  The replacement unit 26 receives the baseband transmission signal output from the modulation unit 17 and further replaces each component of the input I signal and Q signal of the transmission signal. The replacement unit 26 outputs the baseband transmission signal in which the components of the I signal and the Q signal are replaced to the delay unit 18a.

  The multiplication process in the mixer 9a will be described using mathematical expressions. The two high-frequency signals RF1 and RF2 are expressed by Equation (5) and Equation (6). Note that the phase error between the two high-frequency signals RF1 and RF2 is (90 ° [degrees]) when the parameter X = 0 by exchanging the I component and the Q component of the baseband transmission signal of the replacement unit 24 of the first branch A. + Φ).

  In Expression (5), the parameter X is a variable from −180 ° [degree] to + 180 ° [degree], and is a phase delay amount in the delay device 6a of the first branch Aa. The delay control unit 23a delays the phase of the baseband transmission signal in the delay unit 6 among the delay unit 6a of the first branch Aa and the delay unit 12a of the second branch Ba. However, the delay control unit 23a may delay the phase of the baseband transmission signal in the delay unit 12a.

  In the equation (6), the parameter φ is a phase generated between the two high-frequency signals RF1 and RF2 due to the up-conversion of the mixers 8 and 14 in the adjacent branches (first branch Aa and second branch Ba). Represents an error. The parameter φ is in the vicinity of 0 ° [degree] (for example, 0 ° [degree] to 10 ° [degree]), for example, 5 ° [degree].

  The mixer 9a multiplies the two high-frequency signals RF1 and RF2, and outputs the multiplication processing result Y to the LPF 10a (see Expression (7)). In Equation (7), the parameter Y represents the result of multiplication processing of the two high-frequency signals RF1 and RF2. In Expression (7), the multiplication processing result Y of the mixer 9a includes a signal of a sum component of a high frequency component twice the angular velocity ω and a DC component that does not depend on the angular velocity ω.

  The LPF 10a removes high-frequency component signals exceeding a predetermined cutoff frequency. The LPF 10a removes the first term component of Equation (7) corresponding to the high frequency component from the multiplication result Y (see Equation (7)) of the mixer 9a, and switches the DC component signal Z independent of the angular velocity ω to the switch 21. (See equation (8)). That is, in the inter-branch correction apparatus 100a of the phased array antenna, the output signal Z of the LPF 10a becomes a low-frequency fixed DC component from which a high-frequency component (for example, millimeter wave) has been removed.

  The delay control unit 23a determines the phase delay amount of the baseband transmission signal in the delay unit 6a of the first branch Aa or the delay unit 12a of the second branch Ba based on the output signal Z of the LPF 10a converted by the ADC 22. . The inter-branch correction apparatus 100a of the phased array antenna delays the phase of the baseband transmission signal in the delay device 6a of the first branch Aa. Therefore, the delay control unit 23a determines the phase delay amount of the baseband transmission signal in the delay device 6a of the first branch Aa based on the output signal Z of the LPF 10a converted by the ADC 22.

  The delay control unit 23a outputs a delay control instruction including the determined phase delay amount to any one of the delay unit 6a or the delay unit 12a among the adjacent first branch Aa and second branch Ba. That is, the delay control unit 23a transmits the phase of the baseband transmission signal modulated in any branch to any one of the delay units 6a or 12a of the adjacent first branch Aa and second branch Ba. The determined phase delay amount is delayed.

  In the present embodiment, the delay control unit 23a transmits the phase of the baseband transmission signal modulated by the modulation unit 5 to the delay unit 6a of the first branch Aa out of the adjacent first branch Aa and second branch Ba. The determined phase delay amount is delayed.

  Determination of the phase delay amount in the delay control unit 23a will be described with reference to FIG. FIG. 4 is a graph showing a simulation result of the relationship between the phase delay amount in the delay device 6a of the first branch Aa and the output signal Z of the LPF 10a.

  In FIG. 4, the horizontal axis represents the parameter (X + 90 ° [degrees]) because the baseband phase is shifted by 90 ° [degrees] due to the exchange of the I signal and the Q signal in the replacement unit 24 of the first branch Aa. The In the figure, the vertical axis represents the output signal Z of the LPF 10a.

  In FIG. 4, a phase error φ of 5 ° [degrees] occurs between the high-frequency signal RF1 from the first branch Aa and the high-frequency signal RF2 from the second branch Ba (φ = 5). In FIG. 4, the output signal Z of the LPF 10a changes the parameter X, and when the phase component of the formula (8) is 90 ° [degree], that is, zero value at X (= φ) = 5 ° [degree]. It becomes.

  In FIG. 4, the delay control unit 23a determines the parameter X (5 ° [degree] in FIG. 4) when the output signal Z of the LPF 10 is zero as the baseband in the delay unit 6a of the first branch Aa. This is determined as the phase delay amount of the transmission signal. The delay control unit 23a determines the phase delay of the phase of the baseband transmission signal modulated by the modulation unit 5 to the delay unit 6a of the first branch Aa out of the adjacent first branch Aa and second branch Ba. Delay by an amount (5 [deg.]). The delay control unit 23a does not delay the phase of the baseband transmission signal modulated by the modulation unit 11 in the delay unit 12a of the second branch Ba.

  Also, the delay control unit 23a determines the phase of the baseband transmission signal modulated by the modulation unit 11 to the delay unit 12a of the second branch Ba of the adjacent first branch Aa and second branch Ba. You may delay by the amount of phase delays (-5 degree [degree]) equivalent to the reverse phase part of phase delay amount. The delay control unit 23a does not delay the phase of the baseband transmission signal modulated by the modulation unit 5 in the delay unit 6a of the first branch Aa.

  As described above, in the inter-branch correction apparatus 100a for the phased array antenna, the phase error φ between the two high-frequency signals RF1 and RF2 output from the adjacent first branch Aa and second branch Ba is close to 0 ° [degree]. In some cases, the components of the I signal and the Q signal of the baseband transmission signal are switched in any branch. By replacing each component, the phase error between the two high-frequency signals RF1 and RF2 becomes (90 ° [degree] + φ).

  Further, the inter-branch correction apparatus 100a of the phased array antenna determines the phase delay amount in the delay device 6a or the delay device 12a based on the output signal of the LPF 10a converted by the ADC 22. Further, the inter-branch correction apparatus 100a of the phased array antenna determines the phase of the baseband transmission signal modulated in each branch corresponding to the delay unit 6a or the delay unit 12a to the delay unit 6a or the delay unit 12a. Delay by the amount of phase delay.

  Thereby, according to the inter-branch correction apparatus 100a of the phased array antenna, in addition to the effect of the first embodiment, the phase error between the high-frequency signals RF1 and RF2 is obtained by switching the I signal and the Q signal in any branch Can be determined with high accuracy in the vicinity of 90 ° [degree] where the ADC 22 has high detection accuracy. The inter-branch correction apparatus 100a of the phased array antenna can use, for example, the ADC 22a having a resolution equivalent to 7 bits, whereas the ADC 22 having a resolution equivalent to 14 bits is necessary in the first embodiment.

  Therefore, the inter-branch correction apparatus 100a of the phased array antenna can easily determine the phase delay amount in the delay device 6a or the delay device 12a based on the zero value of the output signal of the LPF 10a converted by the ADC 22a.

(Third embodiment)
In the third embodiment, when there is no phase error generated between two high-frequency signals output from adjacent branches and the phases of the two high-frequency signals match, the phase adjustment table is used. A predetermined phase difference is formed between the local signals supplied to the branches.

  For example, when there is no phase error generated between the two high-frequency signals RF1 and RF2 output from the first branch Ab and the second branch Bb, and the phases of the high-frequency signals RF1 and RF2 match, A case where a phase difference of 10 ° [degrees] is formed between the local signals Lo1 and Lo2 supplied to 14 will be described.

  FIG. 5 is a block diagram illustrating an internal configuration of the inter-branch correction apparatus 100b for the phased array antenna according to the third embodiment. Constituent elements that operate in the same manner as in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different contents will be described.

  A phased array antenna inter-branch correction apparatus 100b includes a first branch Ab, a second branch Bb, a third branch Cb, a mixer 9b, an LPF 10b, a mixer 15b, an LPF 16b, a switch 21, an ADC 22, a plurality of (N) branches. The configuration includes a delay control unit 23b, a memory M as a memory unit, and a local signal generation unit LoGenb.

  The first branch Ab includes a modulation unit 5, a DAC 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch Bb includes a modulation unit 11, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch Cb includes a modulation unit 17, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  The memory M is configured using a flash memory or a hard disk built in the inter-branch correction apparatus 100b of the phased array antenna, and stores a phase adjustment table PTB. The phase adjustment table PTB will be described with reference to FIG. FIG. 6 is an explanatory diagram illustrating an example of the phase adjustment table PTB.

  The phase adjustment table PTB associates the phase difference formed between the local signals (for example, Lo1 and Lo2) supplied to each branch and the ratio of the output value of the ADC 22 to the maximum value. When the phase difference formed between the local signals is 10 ° [degrees], the ratio of the output value of the ADC 22 to the maximum value is 0.9848. Similarly, when the phase difference formed between the local signals is 20 ° [degrees], the ratio of the output value of the ADC 22 to the maximum value is 0.9396. Similarly, when the phase difference formed between the local signals is 30 ° [degrees], the ratio of the output value of the ADC 22 to the maximum value is 0.8660.

  Based on the output signal Z of the LPF 10b converted by the ADC 22 and the phase adjustment table PTB, the delay control unit 23b sends a phase difference (for example, 10 ° [degree]) between the local signals Lo1 and Lo2 to the local signal generation unit LoGenb. To form. That is, the delay control unit 23b causes the output signal Z of the LPF 10b converted by the ADC 22 to have a value (0.9848) corresponding to the phase difference (10 ° [degree]) between the local signals Lo1 and Lo2. Then, the phase of the local signal generator LoGenb is adjusted, and a phase difference of 10 ° [degree] is formed between the local signals Lo1 and Lo2.

  The local signal generation unit LoGenb generates the local signals Lo1 and Lo2 in which a phase difference of 10 ° [degrees] is formed between the local signals Lo1 and Lo2 in accordance with an instruction from the delay control unit 23b. The local signal generation unit LoGenb supplies the generated local signals Lo1 and Lo2 to the mixer 8 of the first branch Ab and the mixer 14 of the second branch Bb, respectively. As a result, a phase difference of 10 ° [degree] between the two high-frequency signals from the first branch Ab and the second branch Bb is formed.

  Note that the local signal generation unit LoGenb includes a transmitter and a phase shifter, and controls the phase shift delay amount of the phase shifter, for example, in order to form a phase difference.

  As described above, the inter-branch correction device 100b of the phased array antenna is supplied to each branch based on the phase adjustment table PTB when the phases of two high-frequency signals output from adjacent branches match. A predetermined phase difference is formed between the local signals. The delay control unit 23b outputs the local signal so that the output signal Z of the LPF 10b converted by the ADC 22 becomes a value (0.9848) corresponding to the phase difference (for example, 10 ° [degree]) between the local signals Lo1 and Lo2. The phase delay amount of the phase shifter of the generation unit LoGenb is adjusted, and a phase difference of 10 ° [degree] is formed between the local signals Lo1 and Lo2.

  Thereby, according to the inter-branch correction apparatus 100b of the phased array antenna, by adjusting the phase difference between the local signals when the phases of the two high-frequency signals output from the adjacent branches match. A desired phase difference can be formed between adjacent branches. Therefore, according to the inter-branch correction apparatus 100b of the phased array antenna, a desired phase difference can be individually formed between two high-frequency signals output from adjacent branches, and the phased array technique can be easily realized. For example, the inter-branch correction apparatus 100b of the phased array antenna can form a phase difference of 10 ° [degree] between the first branch Ab and the second branch Bb, and between the second branch Bb and the third branch Cb. A phase difference of −10 ° [degree] can be formed.

  In the third embodiment described above, the inter-branch correction device 100b of the phased array antenna has no phase error generated between two high-frequency signals from adjacent branches, and each phase of the two high-frequency signals is Even when they do not coincide with each other, a desired phase difference can be similarly formed between adjacent branches. For example, the inter-branch correction apparatus 100b of the phased array antenna adjusts the output signal Z of the LPF 10b converted by the ADC 22 to a value corresponding to the desired phase difference of the phase adjustment table PTB, thereby similarly obtaining the desired phase difference. Can be formed.

(Fourth embodiment)
In the fourth embodiment, when there is a phase error between two high-frequency signals output from adjacent branches, as described in the first embodiment, after canceling the phase error, A desired phase difference is formed between each branch.

  For example, when a phase error occurs between the two high-frequency signals RF1 and RF2 output from the first branch Ac and the second branch Bc, the phase of the baseband transmission signal is changed in the delay unit 6 of the first branch Ac. Delay the phase error. Furthermore, a case where a desired phase difference (10 ° [degree]) between the first branch Ac and the second branch Bc is formed after canceling the phase error will be described.

  FIG. 7 is a block diagram illustrating an internal configuration of the inter-branch correction apparatus 100c for the phased array antenna according to the fourth embodiment. Constituent elements that operate in the same manner as in the third embodiment are denoted by the same reference numerals, description thereof is omitted, and different contents will be described.

  A phased array antenna inter-branch correction apparatus 100c includes a plurality of (N) branches, ie, a first branch Ac, a second branch Bc, a third branch Cc, a mixer 9c, an LPF 10c, a mixer 15c, an LPF 16c, a switch 21, an ADC 22, The delay control unit 23c includes a memory M as a memory unit and a local signal generation unit LoGenc.

  The first branch Ac includes a modulation unit 5, a delay unit 6c as a delay unit, a DAC 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch Bc includes a modulation unit 11, a delay unit 12c as a delay unit, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch Cc includes a modulation unit 17, a delay unit 18c as a delay unit, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  The delay control unit 23c determines the phase delay amount of the baseband transmission signal in the delay unit 6c of the first branch Ac based on the output signal Z of the LPF 10c converted by the ADC 22. The delay control unit 23c outputs a delay control instruction including the determined phase delay amount to the delay device 6c of the first branch Ac. That is, the delay control unit 23c causes the delay unit 6c of the first branch Ac to delay the phase of the baseband transmission signal modulated by the modulation unit 5 by the determined phase delay amount. Thereby, as explained in the first embodiment, the inter-branch correction device 100c of the phased array antenna can cancel the phase error between the two high-frequency signals from the first branch Ac and the second branch Bc.

  Further, the delay control unit 23c forms a desired phase difference (10 ° [degree]) between the first branch Ac and the second branch Bc after canceling the phase error. Specifically, the delay control unit 23c sends a phase difference (for example, 10) between the local signals Lo1 and Lo2 to the local signal generation unit LoGenc based on the output signal Z of the LPF 10c converted by the ADC 22 and the phase adjustment table PTB. ° [degree]).

  That is, the delay control unit 23c performs local processing such that the output signal Z of the LPF 10c converted by the ADC 22 has a value (0.9848) corresponding to the phase difference (10 ° [degree]) between the local signals Lo1 and Lo2. The phase delay amount of the phase shifter of the signal generation unit LoGenc is adjusted, and a phase difference of 10 ° [degree] is formed between the local signals Lo1 and Lo2.

  The local signal generation unit LoGenc generates the local signals Lo1 and Lo2 in which a phase difference of 10 ° [degrees] is formed between the local signals Lo1 and Lo2 in accordance with an instruction from the delay control unit 23c. The local signal generation unit LoGenc supplies the generated local signals Lo1 and Lo2 to the mixer 8 of the first branch Ac and the mixer 14 of the second branch Bc, respectively. As a result, a phase difference of 10 ° [degree] between the two high-frequency signals from the first branch Ac and the second branch Bc is formed.

  Note that the local signal generator LoGenc includes a transmitter and a phase shifter, and controls the phase delay amount of the phase shifter, for example, in order to form a phase difference.

  As described above, the inter-branch correction apparatus 100c for the phased array antenna cancels the phase error occurring between the two high-frequency signals from each adjacent branch as described in the first embodiment, and then the phase adjustment table. Based on the PTB, a predetermined phase difference is formed between each local signal supplied to each branch. The delay control unit 23c outputs the local signal so that the output signal Z of the LPF 10c converted by the ADC 22 becomes a value (0.9848) corresponding to the phase difference (for example, 10 ° [degree]) between the local signals Lo1 and Lo2. The phase of the generation unit LoGenb is adjusted, and a phase difference of 10 ° [degree] is formed between the local signals Lo1 and Lo2.

  Thereby, according to the inter-branch correction apparatus 100c of the phased array antenna, the phase error generated between two high-frequency signals output from adjacent branches is canceled and the phase difference between the local signals is adjusted. A desired phase difference can be formed between adjacent branches. Therefore, according to the inter-branch correction apparatus 100c of the phased array antenna, a desired phase difference can be individually formed between two high-frequency signals output from adjacent branches, and the phased array technique can be easily realized. For example, the inter-branch correction apparatus 100b of the phased array antenna can form a phase difference of 10 ° [degree] between the first branch Ab and the second branch Bb, and between the second branch Bb and the third branch Cb. A phase difference of −10 ° [degree] can be formed.

(Fifth embodiment)
In the fifth embodiment, the replacement unit of the second embodiment is provided to eliminate a phase error generated between two high-frequency signals output from adjacent branches, so that each phase of the two high-frequency signals is equal. If it does, a predetermined phase difference is formed between each local signal supplied to each branch based on the phase adjustment table.

  For example, when there is no phase error generated between the two high-frequency signals RF1 and RF2 output from the first branch Ad and the second branch Bd, and the phases of the high-frequency signals RF1 and RF2 match, the mixers 8 and 14 are connected. A case where a phase difference of 10 ° [degree] is formed between the supplied local signals Lo1 and Lo2 will be described.

  FIG. 8 is a block diagram illustrating an internal configuration of the inter-branch correction apparatus 100d for the phased array antenna according to the fifth embodiment. Constituent elements that operate in the same manner as in the second and third embodiments are denoted by the same reference numerals, and description thereof is also omitted.

  A phased array antenna inter-branch correction apparatus 100d includes a plurality of (N) branches, a first branch Ad, a second branch Bd, a third branch Cd, a mixer 9d, an LPF 10d, a mixer 15d, an LPF 16d, a switch 21, an ADC 22, This configuration includes a delay control unit 23d, a memory M as a memory unit, and a local signal generation unit LoGend.

  The first branch Ad is configured to include a modulation unit 5, a replacement unit 24d, a DAC 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch Bd includes a modulation unit 11, a replacement unit 25d, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch Cd includes a modulation unit 17, a replacement unit 26d, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  In the fifth embodiment, contents for canceling a phase error generated between two high-frequency signals from adjacent branches are the same as those in the second embodiment. Furthermore, in the present embodiment, the content of forming a predetermined phase difference between the local signals supplied to the branches based on the phase adjustment table after canceling the phase error is the same as that of the third embodiment.

  As described above, the inter-branch correction apparatus 100d for the phased array antenna switches the components of the I signal and the Q signal of the baseband transmission signal of the first branch Ad in the replacement unit 24d. The inter-branch correction device 100d of the phased array antenna is configured to generate two high-frequency signals by setting a phase error generated between the two high-frequency signals RF1 and RF2 from the adjacent first branch Ad and second branch Bd to 90 ° [degrees] or more. The delay amount of each phase is easily determined.

  Further, the inter-branch correction apparatus 100d for the phased array antenna is configured so that each branch is based on the phase adjustment table when the phases between two high-frequency signals from the adjacent first branch Ad and second branch Bd match. A predetermined phase difference is formed between the local signals supplied to.

  Thereby, according to the inter-branch correction apparatus 100d of the phased array antenna, each phase error can be easily determined and each phase error can be canceled with high accuracy. Furthermore, according to the inter-branch correction apparatus 100d for a phased array antenna, a desired phase difference can be formed between adjacent branches by adjusting the phase difference between local signals.

  Therefore, according to the inter-branch correction apparatus 100d for the phased array antenna, a desired phase difference can be individually formed between two high-frequency signals from each adjacent branch, so that the phased array technique can be easily realized. For example, the inter-branch correction device 100d for the phased array antenna can form a phase difference of 10 ° [degree] between the first branch Ab and the second branch Bb, and between the second branch Bb and the third branch Cb. A phase difference of −10 ° [degree] can be formed.

(Sixth embodiment)
In the sixth embodiment, when a phase error occurs between two high-frequency signals output from adjacent branches, the phase error between the two high-frequency signals is reduced by 90% by the replacement unit of the second embodiment. The phase error is canceled by delaying in the delay unit after setting [degree]. Further, in the present embodiment, a desired phase difference is formed between adjacent branches.

  For example, when a phase error occurs between the two high-frequency signals RF1 and RF2 output from the first branch Ae and the second branch Be, the phase error between the two high-frequency signals RF1 and RF2 is set to 90 by the replacement unit 24e. After setting the degree [degree], the delay unit 6 of the first branch Ac delays the phase of the baseband transmission signal to cancel the phase error. Furthermore, a case where a desired phase difference (10 ° [degree]) between the first branch Ac and the second branch Bc is formed after canceling the phase error will be described.

  FIG. 9 is a block diagram illustrating an internal configuration of the inter-branch correction apparatus 100e for the phased array antenna according to the sixth embodiment. Constituent elements that operate in the same manner as in the second and fourth embodiments are denoted by the same reference numerals, and description thereof is also omitted.

  A phased array antenna inter-branch correction apparatus 100e includes a first branch Ae, a second branch Be, a third branch Ce, a mixer 9e, an LPF 10e, a mixer 15e, an LPF 16e, a switch 21, an ADC 22, The delay control unit 23e includes a memory M as a memory unit and a local signal generation unit LoGene.

  The first branch Ae includes a modulation unit 5, a replacement unit 24e, a delay unit 6e as a delay unit, a DAC 7, a mixer 8 as a mixer unit, and an antenna Ant1. Similarly, the second branch Be includes a modulation unit 11, a replacement unit 25e, a delay unit 12e as a delay unit, a DAC 13, a mixer 14 as a mixer unit, and an antenna Ant2. Further, the third branch Ce includes a modulation unit 17, a replacement unit 26e, a delay unit 18e as a delay unit, a DAC 19, a mixer 20 as a mixer unit, and an antenna Ant3.

  In the sixth embodiment, contents for canceling a phase error generated between two high-frequency signals from adjacent branches are the same as those in the second embodiment. Further, in the present embodiment, the content of forming a predetermined phase difference between the local signals supplied to the respective branches based on the phase adjustment table after canceling the phase error is the same as that of the fourth embodiment.

  As described above, the inter-branch correction apparatus 100e for the phased array antenna can change the phase difference between the local signals supplied to the adjacent branches in the replacement unit 24e when the phase difference is in the vicinity of 0 ° [degree]. The components of the I signal and Q signal of the baseband transmission signal of one branch Ae are switched. Further, the inter-branch correction apparatus 100e for the phased array antenna has the first replacement unit 24e in which the phase difference formed between the local signals supplied to adjacent branches is in the vicinity of 90 ° [degree]. The components of the I signal and the Q signal of the baseband transmission signal of the branch Ae are not interchanged. Information on the phase difference formed between the local signals supplied to the adjacent branches is preferably input to the modulation unit of each branch.

  When the phase difference formed between the local signals supplied to the adjacent branches is near 0 ° [degrees], the inter-branch correction device 100e of the phased array antenna has the adjacent first branch Ae, The phase error generated between the two high-frequency signals RF1 and RF2 from the two branches Be is set to 90 ° [degrees] or more, and the delay amount of each phase of the two high-frequency signals is simply determined (see FIG. 4).

  The inter-branch correction apparatus 100e of the phased array antenna has the adjacent first branch Ae, the second branch when the phase difference formed between the local signals supplied to the adjacent branches is in the vicinity of 90 ° [degree]. The phase error generated between the two high-frequency signals RF1 and RF2 from the two branches Be is determined with high accuracy (see FIG. 2).

  Further, the inter-branch correction apparatus 100e for the phased array antenna is configured so that each branch is based on the phase adjustment table when the phases between two high-frequency signals from the adjacent first branch Ae and second branch Be match. A predetermined phase difference is formed between the local signals supplied to.

  Thereby, according to the inter-branch correction apparatus 100e of the phased array antenna, it is possible to easily determine each phase error of two high-frequency signals from each adjacent branch and cancel each phase error with high accuracy. Furthermore, according to the inter-branch correction apparatus 100e of the phased array antenna, it is possible to form a desired phase difference between adjacent branches by adjusting the phase difference between the local signals.

  Therefore, according to the inter-branch correction device 100d of the phased array antenna, a desired difference between two high-frequency signals from each adjacent branch is determined according to the phase difference formed between each local signal supplied to each adjacent branch. Phase difference can be formed individually, and phased array technology can be realized easily. For example, the inter-branch correction apparatus 100e of the phased array antenna can form a phase difference of 10 ° [degree] between the first branch Ae and the second branch Be, and between the second branch Be and the third branch Ce. A phase difference of −10 ° [degree] can be formed.

  While various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  In each of the above-described embodiments, the example in which the mixers 9 to 9e and 15 to 15e are used as the frequency conversion unit has been described. However, as illustrated in FIG. 10, the nonlinear element 40 (for example, a diode) is used as the frequency conversion unit. You may comprise. FIG. 10 is a block diagram showing a configuration example in which a non-linear element 40 is used in place of the mixer 9 as circuit elements for inputting the high-frequency signal RF1 from the first branch A and the high-frequency signal RF2 from the second branch B, respectively. .

  In FIG. 10, the high-frequency signal RF1 of the first branch A and the high-frequency signal RF2 of the second branch B are combined (added) at the terminal T1 and input to the nonlinear element 40. The terminal T1 is a coupling point where the signal line of the high-frequency signal RF1 from the first branch A and the signal line of the high-frequency signal RF2 from the second branch B are short-circuited. In FIG. 10, the high-frequency signal RF1 of the first branch A and the high-frequency signal RF2 of the second branch B are not coupled to the terminal T1 and input to the nonlinear element 40 by a short circuit of the signal line, but are directional coupled. It may be input to the non-linear element 40 via a device.

  The nonlinear element 40 has input / output characteristics represented by Expression (9), and outputs, for example, a square component (second-order component) of the sum signal of the two high-frequency signals RF1 and RF2 to the LPF 10.

  In Equation (9), the parameter V represents an input signal, and the parameter W represents an output signal. Further, the coefficients An,..., A3, A2, A1, and A0 satisfy the relationship of Expression (10), and the higher order coefficients approach zero.

  Assume that two high-frequency signals RF1 and RF2 represented by the mathematical formulas (1) and (2) are input to the nonlinear element 40, respectively. The nonlinear element 40 outputs the second-order component W (V) of the two high-frequency signals RF1 and RF2 to the LPF 10 (see Expression (11)). In Equation (11), the second-order component coefficient A2 in Equation (9) is not considered.

  The LPF 10 removes high-frequency component signals exceeding a predetermined cutoff frequency. The LPF 10 removes the first term component of Equation (11) corresponding to the high frequency component from the output result W (see Equation (11)) from the nonlinear element 40, and switches the signal Z of the DC component that does not depend on the angular velocity ω. 21 (see equation (12)). That is, in the inter-branch correction apparatus 100 of the phased array antenna, the output signal Z of the LPF 10 becomes a low-frequency fixed DC component from which a high-frequency component (for example, millimeter wave) has been removed. Since the operations after the LPF 10 are the same as those in the above-described embodiments, description thereof will be omitted.

  INDUSTRIAL APPLICABILITY The present invention is useful as a transmission device or a radar device that can accurately correct a phase error between high frequency signals in each branch provided corresponding to each antenna constituting a phased array antenna without increasing the circuit scale. is there.

5, 11, 17 Modulators 6, 6a, 6c, 6e, 12, 12a, 12c, 12e, 18, 18a, 18c, 18e Delay devices 7, 13, 19 DAC
8, 9, 14, 15, 20 Mixer 10, 10a, 10b, 10c, 10d, 10e, 16, 16a, 16b, 16c, 16d, 16e LPF
21 Switch (SW)
22 ADC
23, 23a, 23b, 23c, 23d, 23e Delay control unit 24, 24d, 24e, 25, 25d, 25e, 26, 26d, 26e Replacement unit 40 Nonlinear element 100, 100a, 100b, 100c, 100d, 100e Phased array antenna Correction device A, Aa, Ab, Ac, Ad, Ae of the first branch Ant1, Ant2, Ant3 Antenna B, Ba, Bb, Bc, Bd, Be Second branch C, Ca, Cb, Cc, Cd, Ce Third branch LoGen, LoGena, LoGenb, LoGenc, LoGend, LoGene Local signal generator M Memory PTB Phase adjustment table

Claims (7)

A modulation unit that modulates a baseband transmission signal, a delay unit that delays the phase of the modulated transmission signal, a mixer unit that converts the delayed transmission signal into a high-frequency signal, and the high-frequency signal transmitted An inter-branch correction device for a phased array antenna having a plurality of branches including at least an antenna to perform,
A frequency converter that converts the frequency based on the two high-frequency signals output from each of the adjacent branches;
A filter unit that extracts a DC component based on an output signal from the frequency conversion unit;
A delay control unit that determines a predetermined phase delay amount in the delay unit of the branch based on the DC component extracted by the filter unit;
The delay control unit causes the delay unit of any one of the adjacent branches to delay the phase of the transmission signal modulated in any of the branches by the determined predetermined delay amount Phased array antenna inter-branch correction device. The inter-branch correction device for a phased array antenna according to claim 1,
Each branch is
An inter-branch correction apparatus for a phased array antenna, further comprising: a replacement unit that replaces each component of the in-phase signal of the transmission signal modulated by the modulation unit and the quadrature signal of the transmission signal modulated by the modulation unit . The inter-branch correction device for a phased array antenna according to claim 1 or 2,
A local signal generation unit that generates a local signal supplied to the mixer unit of each branch;
A memory unit for storing a phase adjustment table for associating a phase difference between the supplied local signals and a ratio of the DC component extracted by the filter unit with respect to the maximum value;
The delay control unit causes the local signal generation unit to form a predetermined phase difference between the local signals supplied to the mixer units of the adjacent branches based on the phase adjustment table. Antenna inter-branch correction device. The inter-branch correction device for a phased array antenna according to claim 1,
The inter-branch correction apparatus for a phased array antenna, wherein the delay control unit determines a predetermined phase delay amount in the delay unit of the branch based on the maximum value of the DC component extracted by the filter unit. The inter-branch correction device for a phased array antenna according to claim 2,
The delay control unit is an inter-branch correction device for a phased array antenna that determines a predetermined phase delay amount in the delay unit of the branch based on a zero value of the DC component extracted by the filter unit. The inter-branch correction device for a phased array antenna according to any one of claims 1 to 5,
The inter-branch correction apparatus for a phased array antenna, wherein the frequency conversion unit is configured using a nonlinear element unit that outputs a signal of a predetermined order component based on a sum signal of two high-frequency signals from each of the adjacent branches. . A modulation unit that modulates a baseband transmission signal, a delay unit that delays the phase of the modulated transmission signal, a mixer unit that converts the delayed transmission signal into a high-frequency signal, and the high-frequency signal transmitted An inter-branch correction method in an inter-branch correction device for a phased array antenna having a plurality of branches including an antenna to perform,
Converting the frequency based on the two high-frequency signals output from each of the adjacent branches;
Extracting a DC component based on the output signal output by the frequency conversion;
Determining a predetermined phase delay amount in the delay unit of the branch based on the extracted DC component;
A step of delaying the phase of the transmission signal modulated in any of the branches to the determined predetermined delay amount in any one of the adjacent branches. Correction method between array antenna branches.

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