JP2003032033A - Active phased array antenna and transmission device using the same - Google Patents

Abstract

(57) [Problem] To provide an active phased array antenna capable of forming a feedback loop including an antenna system and capable of monitoring with high accuracy without being affected by mutual coupling from an adjacent antenna element or a sub-array. The purpose is to provide. SOLUTION: Since a monitor slot antenna element 52 formed in an intermediate layer between a lower metal plate 48 and an upper metal plate 41 and shifted from an upper portion of an excitation slot antenna element 49 is provided, power is supplied to an active phased array antenna. Even with the configuration in which the amplifier 45 is integrated, a feedback loop including an antenna system can be configured, and highly accurate monitoring of a transmission radio wave becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active phased array antenna and a transmitter using the same.
In particular, the present invention relates to an active phased array antenna in which an antenna element and a semiconductor device are integrated, and a transmitter using the same.

[0002]

2. Description of the Related Art In recent years, an antenna of a mobile SNG (news material transmission) device having an electronic tracking function and transmitting information from a mobile, a satellite broadcasting receiving antenna capable of multi-beam or spatial beam scanning, or mounted on a satellite An active phased array antenna has been developed as a transmission / reception antenna for mobile phones.

FIG. 6 is a circuit diagram showing an example of a conventional active phased array antenna used in a radar device. In the figure, the transmission pulse signal transmitted from the transmitter 7 is supplied to the power distributor 9 via the circulator 10 and distributed to the phase shifters 6 _{1 to} 6 _n via the power distributor 9. The phase shifters 6 _{1 to} 6 _n set the input transmission pulse signal to a predetermined phase, and the second circulators 4 ₁ to 4
and output to the power amplifiers 3 _{1 to} 3 _n via _n . The power amplifiers 3 _{1 to} 3 _n amplify the input transmission pulse signals and output the amplified transmission pulse signals to the antenna elements 1 ₁ to 1 _n . Antenna element 1 ₁ ~
1 _n radiates the input transmission pulse signal toward the observation target.

The reflected waves of the transmission pulse signal reflected by the observation target are received by the antenna elements 1 ₁ to 1 _n . Received signal received by the antenna element ₁ 1 to 1 _n, via a first circulator ₂ 1 to 2 _n low-noise amplifier ₅ 1 to 5 _n
The received signal guided to and input to is amplified and output to the phase shifters 6 _{1 to} 6 _n via the second circulators 4 ₁ to 4 _n . The phase shifters 6 _{1 to} 6 _n control the input received signals to have a predetermined phase and supply the received signals to the power distributor 9. Power distributor 9
The circulator 10 synthesizes the received signals that have been settled.
Is output to the receiver 8 via which the observation data is acquired. At this time, the phase shifters 6 _{1 to} 6 _n control the amount of phase shift via a beam controller (not shown) to control the electromagnetic waves transmitted and received to the phase required for beam scanning.

[0005] a plurality of power amplifiers ₃ 1 to 3 _n of the output to the directional coupler ₁₁ 1 to 11 _n, respectively, the output of the power amplifier ₃ 1 to 3 _n in this directional coupler ₁₁ 1 to 11 _n A part is extracted as a monitor signal, and this monitor signal is detected by the detectors 12 _{1 to} 12 _n and output by a monitor device (not shown) to detect the operating states of the plurality of power amplifiers 3 _{1 to} 3 _n . Thereby, the amplitude and phase of the radio wave radiated from each of the antenna elements 1 ₁ to 1 _n can be obtained, and the antenna beam can be scanned in a desired direction with high accuracy.

FIG. 7 shows a plan view of an example of a conventional planar active phased array antenna used in a mobile SNG device. In the figure, the multi-layer substrate planar active phased array antenna 20 is provided with a patch 22 of 8 × 8 elements, and each patch 22 is formed by a pair of a radiation antenna element and a monitor antenna element. In the figure, one patch of the monitoring antenna element located at the center of the array shown by hatching is used as the transmission monitoring antenna element.

8A and 8B are a sectional view and a plan view of each patch. Multilayer substrates include substrates 31 to 34
The radiation antenna element 35 for transmission is formed on the substrate 32, and the transmission port of the radiation antenna element 35 is formed by the through holes 36 on the substrates 33, 34.
It is connected to the transmission power supply line 37 formed between them, and is connected to the transmission connector via the transmission power supply line 37.

The substrate 31 is provided with a monitor antenna element 38 which is also formed by a parasitic resonance patch formed by etching. The monitor antenna element 38 used as the transmission monitor antenna element is connected to the monitor output connector via a feeder line formed on the same plane.

In this structure, the monitor antenna element is laminated on the radiating element, so that a small and thin structure can be obtained. In addition, since the amplitude and phase of the transmitted radio wave can be directly monitored and a feedback system including the antenna is included in the loop, it is possible to control the amplitude and phase with high accuracy by compensating for changes in the characteristics of the antenna unit.

[0010]

In the prior art of FIG. 6,
The monitor device is an antenna element 1₁~ 1_nAnd power amplifier 3₁
~ 3_nDirectional coupler 11 mounted between₁~ 11
_nSince the transmission signal is extracted by
The feedback loop does not include
Multiplexing due to the influence of radiating elements and impedance mismatch
Vibration of transmitted radio waves radiated into space due to reflection etc.
The width and phase cannot be monitored accurately. In addition,
Antenna element 1₁~ 1_nAnd power amplifier 3₁~ 3_nIntegrated
Applied to the active phased array antenna
Directional coupler 11₁~ 11_nIs relatively large,
Build a small active phased array antenna
Becomes difficult. Furthermore, this directional coupler 11₁~
11_nThe antenna element 1₁~ 1 _nAnd power amplifier 3₁~ 3
_nActive phased array if inserted between
The characteristics of the antenna are affected and the transmitted radio waves are accurately monitored.
There is a problem that you can not.

In the prior art shown in FIGS. 7 and 8, since the monitoring antenna element 38 is laminated on the radiation antenna element 35, the monitoring including the antenna system can be performed. Since the monitoring antenna element 38 is formed by being laminated on the upper portion, there is a problem that radiation characteristics are directly affected or accurate monitoring cannot be performed due to coupling from an adjacent antenna element or sub-array.

The present invention has been made in view of the above points, and a feedback loop including an antenna system can be configured, and high-accuracy monitoring is possible without being affected by mutual coupling from adjacent antenna elements or subarrays. It is an object of the present invention to provide an active phased array antenna.

[0013]

According to a first aspect of the present invention, there is provided a plurality of lower metal plates on which an exciting slot antenna element excited by an output line of a power amplifier is formed, and a plurality of upper metal plates. An upper layer metal plate having an array of radiation slot antenna elements, and a monitor slot antenna formed in an intermediate layer between the lower layer metal plate and the upper layer metal plate and displaced from the upper portion of the excitation slot antenna element. An active phased array antenna, since the electromagnetic wave radiated from the exciting slot antenna element is spatially distributed and electromagnetically coupled to the plurality of radiating slot antenna elements and the monitor slot antenna element. Even if the power amplifier is integrated in the antenna, a feedback loop including the antenna system can be configured and highly accurate transmission can be achieved. Monitor of the wave is possible. Also,
Since the monitor slot antenna element is formed between the lower layer metal plate forming the excitation slot antenna element and the upper layer metal plate forming the radiating slot antenna element,
Since there is no direct effect of mutual coupling from adjacent active phased array antennas or subarrays,
High-accuracy monitoring is possible and the radiation pattern of the active phased array antenna is not affected. Also, since the monitor slot antenna element can be freely arranged between the lower metal plate and the upper metal plate,
The degree of electromagnetic coupling can be freely adjusted and monitored. Furthermore, since the monitoring is performed by electromagnetic coupling, it is possible to monitor the transmitted radio waves efficiently and accurately even at a high frequency.

According to a second aspect of the present invention, in the active phased array antenna according to the first aspect, an amplitude and a phase of a signal monitored by the monitor slot antenna element are provided in an intermediate layer in which the monitor slot antenna element is formed. Since a circuit for detecting the amplitude of the transmitted radio wave is configured inside the active antenna, an active phased array antenna including a circuit for detecting the amplitude and the phase of the transmitted radio wave is used. It can be manufactured at low cost.

According to a third aspect of the present invention, the active phased array antenna according to the first or second aspect is arranged as a sub-array in a two-dimensional plane in an array form.
The amplitude and phase of the radio wave radiated from each sub array can be detected, and the beam control of the antenna can be performed with high accuracy.

[0016]

1, 2 and 3 are an exploded perspective view, a perspective view and a sectional view of a first embodiment of an active phased array antenna of the present invention. In the figure, the radiation slot array plate 41 made of metal is formed with a plurality of radiation slots 42 arranged in a line so that the polarization directions coincide with each other in the x direction at regular intervals. That is, each radiation slot 42 is a rectangular hole long in the y direction and short in the x direction.

Further, the metal base 43 is provided with a metal groove 47 for accommodating the strip conductor 44, the power amplifier 45 and the strip conductor 46. An input signal is supplied to the strip conductor 44, the power amplifier 45 amplifies the input signal supplied from the strip conductor 44, supplies the amplified signal to the strip conductor 46, and feeds the excitation slot 49 from the strip conductor 46. The upper surface of the metal base 43 is covered with an exciting slot plate 48 made of metal.
In FIG. 8, an excitation slot 49 for exciting the radiation slot 42 is formed. The excitation slot 49 is a rectangular hole that is long in the y direction and short in the x direction.

A dielectric substrate 51 is arranged between the radiation slot array plate 41 and the metal base 43, and a monitor antenna element 52 is formed on the upper surface of the dielectric substrate 51 with a rectangular metal film. The dielectric substrate 51 and the monitoring antenna element 52 supported by the dielectric substrate 51 constitute a transmission radio wave monitoring element 53. Here, the monitor antenna element 52 is not stacked on the upper portion of the excitation slot 49, but is displaced in the y direction, for example.

The strip conductor 44, the metal base 43, and the excitation slot plate 48 make the input triplate line 54.
And the strip conductor 46, the metal base 43, and the excitation slot plate 48 form an output triplate line 55.
Is configured. And the input triplate line 5
4, output triplate line 55, and power amplifier 45
The metal base 43 and the excitation slot plate 48 in which the excitation slot 49 is formed constitute a one-element active phased array antenna for excitation.

Here, the signal flow will be described. The high-frequency signal input from the input terminal T1 to the strip conductor 44 is transmitted through the input triplate line 54 and the power amplifier 4
Input to 5. The signal amplified and output by the power amplifier 45 is transmitted through the output triplate line 55 and electromagnetically coupled to the excitation slot 49 formed on the excitation slot plate 48. The electromagnetically coupled high-frequency signal is radiated from the excitation slot 49, electromagnetically coupled to the plurality of radiation slots 42 formed on the radiation slot array plate 41, and spatially distributed to the plurality of radiation slots 4.
It is emitted from 2 to the space.

A part of the high frequency signal radiated from the excitation slot 49 is a transmission radio wave monitoring element 53 arranged between the radiation slot array plate 41 and the metal base 43.
The monitor antenna element 52 of is excited by electromagnetic coupling,
It is output from the monitor output terminal R1 connected to the monitor antenna element 52.

In the present embodiment, a plurality of radiation slots 42 are arranged in an array on the upper portion of the excitation slot plate 48 in which the excitation slots 49 excited by the strip conductor 46 which is the output line of the power amplifier 45 are formed. In the structure in which the radiating slot array plate 41 is arranged, the electromagnetic wave radiated from the lower layer exciting slot 49 is spatially distributed and electromagnetically coupled to the upper layer radiating slot 42 with an appropriate coupling degree. By forming the monitoring antenna element 52 at a position displaced from the upper part of the excitation slot 49 on the lower intermediate layer, the antenna system is included even if the active phased array antenna and the power amplifier 45 are integrated. Since a feedback loop can be configured, it is possible to monitor transmitted radio waves with high accuracy.

Further, the monitor antenna element 52 has the excitation slot 49 between the emission slot array plate 41 having the emission slot 42 formed therein and the excitation slot plate 48 having the excitation slot 49 formed therein. Since they are arranged so as to be offset from the upper portion, there is no direct influence due to mutual coupling from the adjacent active antennas or sub-arrays, high-precision monitoring is possible, and there is no influence on the radiation pattern of the array antennas.

Further, since the monitoring antenna element 52 and the transmission radio wave monitor circuit for detecting the amplitude and phase of the transmission radio wave can be easily constructed inside the active antenna, the active phased array antenna including the transmission radio wave monitor circuit can be manufactured at low cost. It can be manufactured.

Further, the monitor antenna element 52 is freely arranged between the radiation slot array plate 41 having the radiation slot 42 formed therein and the excitation slot plate 48 having the excitation slot 49 formed therein. Therefore, the degree of electromagnetic coupling can be freely adjusted and monitored. Furthermore, since the monitoring is performed by electromagnetic coupling, it is possible to monitor the transmitted radio waves efficiently and accurately even at a high frequency.

FIGS. 4 and 5 are a perspective view and a sectional view of a second embodiment of the active phased array antenna of the present invention. This active phased array antenna has a structure in which the active phased array antenna shown in FIGS. 1 to 3 is used as a sub array and four sub arrays 60 and 6 are provided.
1, 62, 63 are arranged in an array on a two-dimensional plane to form an active phased array antenna.
The sub-array is not limited to the array of four arrays, but may be a configuration in which several tens to several hundreds of rows and columns are arrayed in an array.

In FIGS. 4 and 5, four sub arrays 6 are provided.
0, 61, 62, 63 respectively have input terminals T1, T
2, T3, T4 to strip conductors 44 of each sub-array
A high frequency signal is input to the power amplifier 45, and the high frequency signal is transmitted through the input triplate line 54 and input to the power amplifier 45. The signal amplified and output by the power amplifier 45 is transmitted through the output triplate line 55 and electromagnetically coupled to the excitation slot 49 formed on the excitation slot plate 48. The electromagnetically coupled high-frequency signal is radiated from the excitation slot 49, is electromagnetically coupled to the plurality of radiation slots 42 formed on the radiation slot array plate 41, and is spatially distributed to the plurality of radiation arrays of each sub-array. The slots 42 radiate into space.

The excitation slot 49 of each sub-array is also provided.
A part of the high frequency signal radiated from the device is excited by electromagnetic coupling of the monitor antenna element 52 of the transmission radio wave monitor element 53 arranged between the radiating slot array plate 41 and the metal base 43, and the monitor antenna element 52. Monitor output terminals R1, R2, R3, R4 of each sub-array connected to
Is output from. Therefore, monitor output terminals R1, R2
The amplitude and phase of the radio wave radiated from each sub-array can be detected by R3 and R4, and the beam control of the antenna can be performed with high accuracy.

Although the monitor antenna element 52 has a planar structure in the above embodiment, it may be formed of a three-dimensional circuit such as a coaxial line. Further, since it is possible to integrate a transmission radio wave monitor circuit for detecting the amplitude and phase of the transmission radio wave on the dielectric substrate 51 on which the monitoring antenna element 52 is formed, an active phased array antenna incorporating the transmission radio wave monitor circuit. The structure can be further reduced in size and thickness, and it is possible to perform highly accurate beam formation with an active phased array antenna used for a mobile SNG device or for mounting on a satellite.

The excitation slot 49 corresponds to the excitation slot antenna element described in the claims, the excitation slot plate 48 corresponds to the lower metal plate, and the radiation slot 42 corresponds to the radiation slot antenna element. The radiation slot array plate 41 corresponds to the upper metal plate, and the monitor antenna element 52 corresponds to the monitor slot antenna element.

[0031]

As described above, according to the invention of claim 1, even if the active phased array antenna is integrated with the power amplifier, the feedback loop including the antenna system can be configured and the highly accurate transmission radio wave can be obtained. It becomes possible to monitor. Further, since the monitor slot antenna element is formed between the lower layer metal plate forming the excitation slot antenna element and the upper layer metal plate forming the radiating slot antenna element, mutual coupling from the adjacent active phased array antenna or sub array is performed. Since there is no direct influence of the antenna, it is possible to monitor with high accuracy, and there is no influence on the radiation pattern of the active phased array antenna. Further, since the monitor slot antenna element can be freely arranged between the lower metal plate and the upper metal plate, the degree of electromagnetic coupling can be freely adjusted for monitoring. Furthermore, since the monitoring is performed by electromagnetic coupling, it is possible to monitor the transmitted radio waves efficiently and accurately even at a high frequency.

According to the second aspect of the present invention, since the circuit for detecting the amplitude and phase of the transmitted radio wave is formed inside the active antenna, the active phased array antenna including the circuit for detecting the amplitude and phase of the transmitted radio wave. Can be manufactured at low cost.

The invention according to claim 3 is capable of detecting the amplitude and phase of the radio wave radiated from each sub-array,
Beam control of the antenna can be performed with high accuracy.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of an active phased array antenna according to the present invention.

FIG. 2 is a perspective view of a first embodiment of the active phased array antenna of the present invention.

FIG. 3 is a sectional view of a first embodiment of an active phased array antenna of the present invention.

FIG. 4 is a perspective view of a second embodiment of the active phased array antenna of the present invention.

FIG. 5 is a sectional view of a second embodiment of the active phased array antenna of the present invention.

FIG. 6 is a circuit configuration diagram of an example of a conventional active phased array antenna.

FIG. 7 is a plan view of an example of a conventional planar active phased array antenna.

FIG. 8 is a sectional view and a plan view of a patch.

[Explanation of symbols]

41 Radiation slot array plate 42 Radiation slot 43 Metal base 44 strip conductor 45 power amplifier 46 strip conductor 47 metal groove 48 Excitation slot plate 49 Excitation slot 51 Dielectric substrate 52 Monitor antenna element 53 Transmitted radio wave monitor element 54 Tri-plate line for input 55 Output Triplate Line 60, 61, 62, 63 sub-array

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5J021 AA04 AA11 AB05 CA03 DB05                       EA02 FA26 FA32 GA01 HA04                       JA09                 5J045 AA21 AB06 DA03 FA02 HA02                       NA07                 5J070 AD11

Claims (4)

[Claims] 1. In an active phased array antenna integrated with a power amplifier, a lower metal plate on which an excitation slot antenna element excited by an output line of the power amplifier is formed, and a plurality of radiations are provided on the lower metal plate. Upper layer metal plate in which the slot antenna element for an array is formed, and a monitor slot antenna element formed in an intermediate layer between the lower layer metal plate and the upper layer metal plate and displaced from the upper portion of the excitation slot antenna element And an electromagnetic wave radiated from the exciting slot antenna element is spatially distributed and electromagnetically coupled to the plurality of radiating slot antenna elements and the monitor slot antenna element. Array antenna. 2. The active phased array antenna according to claim 1, wherein a circuit for detecting the amplitude and phase of the signal monitored by the monitor slot antenna element is formed in the intermediate layer in which the monitor slot antenna element is formed. Active phased array antenna characterized by the following. 3. An active phased array antenna, wherein the active phased array antenna according to claim 1 or 2 is arranged as a sub-array in a two-dimensional plane in an array shape. 4. A transmitter using the active phased array antenna according to any one of claims 1 to 3.