KR20200060975A - Antenna in which an Array Radiating Element is formed in a Radome - Google Patents

Abstract

The present invention provides an antenna having an array radiating element formed on a radome, which includes a plurality of arranged radiating elements formed on a lower surface of the radome and a laminated substrate portion formed of a plurality of substrates for applying an RF feed signal to each of the radiating elements. Provided is a stacked antenna for 3D beamforming, which has a wideband and good radiation efficiency while reducing the size (thickness) of the entire antenna by forming a radiating element using a laser direct structuring (LDS) plating technology on the lower surface of a low-cost plastic radome.

Description

Antenna in which an array of radiating elements is formed {Antenna in which an Array Radiating Element is formed in a Radome}

The present invention relates to a 3D beam-forming multi-layer antenna for 3D beam-forming in which an array radiating element is formed on a lower surface of a radome using a laser direct structuring (LDS) plating process.

The conventional 3D beam-forming stacked antenna has a stacked structure in which a number of PCB substrates are stacked as shown in FIG. 1, and the uppermost PCB substrate is formed of a dielectric substrate having a low dielectric constant and a thick thickness in order to have broadband characteristics. In order to increase the radiation efficiency, it is formed of a substrate with low dielectric constant loss.

However, the uppermost PCB substrate as described above is not only expensive in material cost, but also has a problem in that there is a physical limitation in reducing the antenna thickness due to the use of a thicker PCB substrate.

Therefore, the overall thickness of the stacked antenna on which the active circuit for forming a 3D beam is mounted is reduced, and the dielectric constant is small, so that the performance of the antenna can be improved, and a realistic and practical 3D beam that can reduce manufacturing cost- The development of forming antennas is urgent.

Korean Registered Patent Publication No. 10-1700403 (2017.02.14.) Korean Registered Patent Publication 10-0572690 (2006.04.19.)

The antenna having an arrayed radiating element formed on the radome according to the present invention forms a radiating element using an LDS (Laser Direct Structuring) plating process on the lower surface of a low-cost plastic radome, thereby reducing the size (thickness) of the entire antenna and radiating while being broadband. It is an object to provide an antenna for efficient beam-forming.

In addition, an object of the present invention is to provide an active phase array antenna capable of 3D beam-forming using an active network having an active element capable of adjusting phase and gain.

The antenna having an array radiating element formed on a radome for forming a 3D beam according to the present invention can significantly reduce manufacturing cost because a high cost substrate is not used by implementing a radiator using LDS plating technology on the lower surface of the radome. It is an object to provide an antenna.

The antenna having an arrayed radiating element formed on a radome for forming a 3D beam according to the present invention provides an active phased array antenna that can be implemented in an ultra-thin manner by reducing the thickness of the antenna by removing the substrate for forming the conventional radiating element. The purpose.

In addition, the antenna having an arrayed radiating element formed on a radome for forming a 3D beam according to the present invention can be manufactured with a thinner thickness compared to the structure of a radiating element formed on the top of a conventional substrate, thereby minimizing air resistance and volume. Therefore, an object of the present invention is to provide an antenna that is easy to install on the top of a mobile vehicle for satellite broadcasting reception.

In order to achieve the above object, an antenna in which an array radiating element is formed on a radome according to an embodiment of the present invention includes a plurality of radiating elements arranged on a lower surface of a radome, and applying a RF feed signal to each of the radiating elements. It characterized in that it comprises a laminated substrate formed of a plurality of substrates.

The stacked substrate portion may further include a power divider for applying a power supply signal to each of the plurality of radiating elements.

The stacked substrate portion may further include a slot portion for opening-coupled feeding and a ground for noise shielding to apply a feed signal from the power divider to each of the radiating elements arranged in plurality.

The stacked substrate portion further includes an active network including active elements capable of adjusting the phase/gain of each of the plurality of radiating elements.

The active network is characterized by having an LNA, an attenuator (gain control unit), a phase shifter, and a SPI (Serial to Parallel Interface) for shifting the phase.

The active network is an active element, a phase shifter for shifting (adjusting) the phase, an attenuator for controlling gain, LNA, and SPI are multi-function chips (MFCs) formed by being integrated in the MMIC by GaAs or CMOS semiconductor processes. ) It is characterized by being a device.

The stacked substrate portion further includes a DC voltage applying portion and a control logic line portion for controlling the phase shifter and attenuator to apply a DC voltage to the active element provided in the active network.

The DC voltage applying unit and the control logic line unit are characterized in that they are formed in a right angle shape as a whole so as not to affect each other.

It characterized in that the plurality of radiating elements arranged on the lower surface of the radome and the laminated substrate portion are formed at regular intervals.

The radiating element arranged in plural on the lower surface of the radome is characterized in that it is either a rectangular microstrip patch element or a circular microstrip patch element.

The radiating element arranged in plural on the lower surface of the radome is characterized in that a 3D beam is formed by adjusting the phase by a phase shifter of the active network.

As described above, the antenna having an array radiating element formed on a radome for forming a 3D beam according to the present invention is formed by forming a radiating element on a lower surface of a low-cost plastic radome by a laser direct structuring (LDS) plating process. While reducing the size (thickness), it has a broadband effect and good radiation efficiency.

The antenna having an arrayed radiating element formed on a radome for forming a 3D beam according to the present invention can realize a radiator using an LDS plating technique on the lower surface of the radome, thereby reducing manufacturing cost by not using a high-cost substrate. There is.

The antenna having an array radiating element formed on a radome for forming a 3D beam according to the present invention has an effect of significantly reducing the thickness of the antenna in an ultra-thin form by removing a substrate for forming a conventional radiating element.

In addition, the antenna having an arrayed radiating element formed on a radome for forming a 3D beam according to the present invention can be manufactured with a thinner thickness compared to the structure of a radiating element formed on the top of a conventional substrate, thereby minimizing air resistance and volume. Therefore, it is easy to install on the top of a mobile vehicle for satellite broadcasting reception.

1 is a perspective view of the stacked 3D beam forming antenna according to the prior art, vertically separated.
2 is an exploded perspective view of an antenna having an array of radiating elements formed on a radome according to the present invention.
3 is a cross-sectional view showing a stacked cross-section of an antenna having an array radiating element formed on a radome according to the present invention.
4 is a view showing a detailed circuit for the power distribution structure of the laminated substrate portion according to an embodiment of the present invention.
5 is a view showing a detailed circuit for the active circuit structure of the laminated substrate portion according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Components having the same function in all the drawings below are omitted by repeated description using the same reference numerals, and terms to be described later are defined in consideration of functions in the present invention, and are used in the specification and claims Is not to be construed as limited to a dictionary meaning, and the inventors are based on the principle that the concept of terms can be properly defined to explain their invention in the best way, meanings and concepts that meet the technical needs of the present invention. Should be interpreted as

Therefore, the embodiments described in this specification are only preferred embodiments of the present invention, and do not express all of the technical needs of the present invention, there are various equivalents and modifications that can replace them at the time of this application. It should be understood that it can.

2 is an exploded perspective view of an antenna in which an array radiating element is formed in a radome according to the present invention, and FIG. 3 is a cross-sectional view showing a stacked cross-section of an antenna in which an array radiating element is formed in a radome according to the present invention. The antenna 10 having an array of radiating elements formed on a radome according to the present invention is formed by discharging the radiating portion 100 and the laminated substrate portion 200 and the radiating portion 100 and the laminated substrate portion 200 as a whole. It is made of an air layer (300).

The radiating part 100 is composed of a radome 110 and an array radiating element 120 arranged in an N×N arrangement in a plurality formed by being printed on a lower surface of the radome 110.

The radome 110 is a thermoplastic resin (εr = 2 ~ 2.5) material, the array radiation element 120 is formed by printing on the lower surface layer of the radome 110 through a laser direct structuring (LDS) plating process do.

In the LDS plating process, a metal layer is selectively patterned using a laser on the surface of a thermoplastic resin (plastic injection material), followed by a primary copper plating process followed by a secondary nickel plating process. In this way, the LDS plating process is capable of plating micro-rough rough plastic resin surfaces through laser processing, thereby ensuring good electrical properties and reliability.

According to a preferred embodiment of the present invention, the radiating element 120 is preferably formed of an array radiating element 120 arranged in N×N arranged in plural on the lower surface of the radome, but if necessary, a single The radiating element 120 may be formed by printing on one or more surfaces of the radome 110 on the upper surface or the lower surface by an LDS plating process.

In addition, the radiating element 120 may be either a square microstrip patch element or a circular microstrip patch element, and may be a slot type radiating element, but is not limited thereto, and is formed in the form of strip lines of various shapes. Can be.

In addition, a plurality of radiating elements arranged on the lower surface of the radome is 3D in a direction in which satellite signals are emitted even when the moving object is rotated or moved vertically by a phase-adjusted feeding signal applied from the laminated substrate unit 200. A beam may be formed to operate as an N×N phased array antenna for satellite broadcast reception.

The stacked substrate portion 200 is formed by stacking a plurality of substrates in order to apply an RF feed signal to each of the radiating elements.

The radiating portion 100 and the stacked substrate portion 200 are formed to be spaced apart at regular intervals, and the spaced space is formed of an air layer (εr=1) 300.

The stacked substrate portion 200 is formed of a plurality of substrates to apply an RF feed signal to each of the radiating elements arranged on the lower surface of the radome, which is arranged in a plurality, and includes a first substrate 210 and a second substrate 220 ) And the third substrate 230.

The first substrate 210 is formed of a first dielectric 211 having a dielectric constant (εr=4.5) as an intermediate layer and a metal layer (Cu, copper) formed on an upper surface of the first dielectric 211 as an upper layer. One ground 212 is formed, a plurality of slots 213 are formed in the first ground 212 formed on the first substrate 210, and the plurality of slots are formed through the plurality of first slots 213. The feed signal from the power distributor 224 is fed to each of the four radiating elements 120 by opening coupling.

The first slot 213 for opening engagement feeding formed in the first ground 212 is formed in a dumbbell shape, and may be formed in various other shapes depending on the case.

The first substrate 210 is a metal layer that is a lower layer of the first dielectric 211 and is formed on the lower surface of the first dielectric 211 and applies a DC voltage to an active element provided in the active network 225. A DC voltage applying unit 214 that is a line for the formation is formed.

The second substrate 220 has a second dielectric layer 221 having a dielectric constant (εr=3.48) as an intermediate layer and a second ground 222 as a metal layer formed on the upper surface of the dielectric 221 as an upper layer. In the second ground 222 formed on an upper portion of the second substrate 220, a plurality of second slots 223 for opening engagement feeding is formed, and the first substrate (through the second slot 223) 210) The power supply signal from the power distributor 224 is transmitted to each of the plurality of radiating elements 120 so as to correspond one-to-one to each of the plurality of first slots 213 formed in the upper layer, the first ground 212. The openings are coupled to allow power feeding.

The second substrate 220 is a metal layer formed on the lower surface of the second dielectric 221 as a lower layer, and a power distributor 224 for transmitting a power supply signal is formed in a network structure corresponding to the plurality of radiating elements. do.

On the lower surface of the dielectric 221, an active network 225 for adjusting the phase and gain of the plurality of radiating elements together with the power divider 224 is formed by a surface-mount type (SMT) process.

In the active network 225, the LNA 225-1, the attenuator (or gain control unit) 225-2, the phase shifter 225-3, and the SPI 225-4, which are active devices, are GaAs or CMOS. It may be formed of a multi-function chip (MFC) device in the form of MMIC, which is formed by integration in a process.

The third substrate 230 is a substrate positioned in an intermediate layer between the first substrate 210 and the second substrate 220, and is provided in an active network 225 of the second substrate 220. It is a substrate for forming a control logic line portion 232 for logically controlling each of the elements 225-1 to 225-6.

By arranging the third substrate 230 between the first substrate 210 and the second substrate 220 as described above, the 1/ formed on the first substrate 210 and the second substrate 220 The DC voltage application unit 214 and the third substrate 230 of the first substrate 210 for applying DC voltage to the active elements provided in the active network 225 by the second grounds 212 and 222 ) To shield noise signals leaking from the control logic line unit 232.

That is, noise signals leaking from the DC voltage applying unit 214 and the control logic line unit 232 are introduced into the radiating element 120 in the upper direction of the first ground 210 of the first substrate 210. The third substrate 230 is shielded by the second ground 222 of the second substrate 220 to shield the power distributor 224 and the active network 225 in the lower direction. It is disposed between the first substrate 210 and the second substrate 220.

In addition, according to the present invention, the feed signal emitted from the power distributor 224 includes a plurality of second slots 223 formed for opening-coupled feeding in the second ground 222 above the second substrate 220 and the The first ground 210 of the first substrate 210 passes through a plurality of first slots 213 formed exclusively for opening coupling feeding, and the openings are respectively engaged in a one-to-one correspondence by the plurality of arrayed radiating elements 120. To be fed.

That is, the power supply signal from the power divider 224 is primarily open-coupled in the upper direction and is discharged upward through the plurality of second slots 223 of the second substrate 220, and the third substrate 230 ) Through the plurality of first slots 213 of the first substrate 210 in an upward direction to the plurality of arrayed radiating elements 120 to be opened and fed.

Accordingly, the first/second grounds 212 and 222 of the first substrate 210 and the second substrate 220 are first/first formed in the first/second grounds 212 and 222. The two slots 213 and 223 are coupled to the radiating element 120 so as to be energized, and secondly, the DC voltage applying unit 214 formed between the first ground 212 and the second ground 222. There is an effect of shielding noise signals leaking from the control logic line part 232 from RF elements arranged in upper and lower directions. That is, by blocking the inflow of noise signals to the radiating element 120, which is an RF element in the upper direction, the power distributor 224 in the lower direction, and the active network 225, malfunctions of the active network and noise is mixed into the RF signal. There is an effect that can be suppressed.

The more detailed description of the third substrate 230 is as follows. The third substrate 230 is a first pre-preg 231 having a dielectric constant (εr=2.35) and a metal layer formed by printing on an upper surface of the first pre-preg 231, a phase shifter and an attenuator A control logic line part 232 for logically controlling is formed, and a second pre-preg (εr = 2.35) of the same material as the first pre-preg 231 is separately disposed on the control logic line part 232. By further including (233), the DC voltage applying unit 214 and the control logic line unit 232 formed on the lower surface of the first dielectric 211 of the first substrate 210 are not connected to each other. To separate.

Meanwhile, according to another embodiment of the present invention, the DC voltage application unit 214 does not form on the lower surface of the first dielectric 211 of the first substrate 210 described above, but instead instead of the second Pre- It may be formed on the upper surface of the preg (233).

4 is a diagram showing a detailed circuit for a 4x4 array power divider of a laminated substrate unit according to an embodiment of the present invention.

As shown, the power distributor 224 formed on the lower surface of the second dielectric layer 221 in the second substrate 220 of the laminated substrate portion 200 according to the present invention, the RF signal is input (transmitted) It has one RF input unit 224-1 and 16 RF output units 224-2 through which RF signals are output (transmitted). Through a plurality of second / first slots (223, 213) for the opening-type feeding of the dumbbell-like formed in the second / first ground (223, 213) that can be corresponded one-to-one at the position of λ/4 length The radiated RF signal is transmitted to the radiating element 120 formed under the radome 110 so that radio waves are radiated (transmitted) in a free space.

The first/second slots 213 and 223 are located between the power divider 224 and the radiating element 120, and the first ground 212 formed with a plurality of first slots 213 located at the top is DC. The noise signal leaking from the voltage application unit 214 and the control logic line unit 232 is shielded from being transmitted to the radiating element.

In addition, the second ground 222 in which a plurality of second slots 223 positioned in the lower direction is formed is a DC voltage applying unit 214 and a noise signal leaking from the control logic line unit 232 is a power divider 224. And shielding the active network 225 from affecting active elements included in a large number.

The DC voltage applying unit 214 and the control logic line unit 232 have a right angle shape as a whole so as not to affect each other (so that interference does not occur between each other), and a first ground 212 so as not to affect the outside. ) And the second ground 222 has a shielding function.

According to another embodiment of the present invention, the first dielectric 211 of the first substrate 210, the second dielectric 211 of the second substrate 220, and the first of the third substrate 230 / The second pre-preg (231, 233) may be manufactured by substituting any one of the electronic circuit fabrication substrate (FR4), RF substrate, and pre-preg according to the substrate manufacturing process.

According to the prior art as shown in Figure 1, in order to have a high-bandwidth, high-gain performance, the substrate 1, 2 (2, 4) between the slot 6 and the radiator 1 has a low dielectric constant and low loss RF substrate. However, the RF substrate applied is expensive, and thus has a problem of increasing manufacturing cost, whereas according to the present invention, the dielectric constant generally required to have broadband and high gain performance is low and the loss is small. It is a structure using an air layer 300 having a lower dielectric constant instead of an expensive RF substrate.

According to another embodiment of the present invention, the air layer 300 may be manufactured by inserting a support that can support the upper radome 110 or a non-conductive dielectric ((εr = 2.2)). 300), the non-conductive dielectric has a dielectric constant of 2.2 and an insertion loss (dissipation factor) of 0.0004 by the RF substrate with the radiating portion 100 and the laminated substrate portion ( 200).

5 is a view showing a detailed circuit for the active network structure of the laminated substrate portion according to an embodiment of the present invention.

As shown, by the SMT process on the upper (if viewed from the bottom) of the power distributor 224 formed on the second dielectric 221 in the second substrate 220 of the laminated substrate portion 200 according to the present invention The active network 225 to be formed may be formed in various structures.

That is, it is possible to form a circuit structure of any one of three types of transmission/reception circuits, transmission/reception circuits, and transmission/reception/combination circuits that are both compatible.

The active network 225 of an antenna in which an array radiating element is formed on a radome according to the present invention is generally referred to as an RF multi-function chip (MFC).

In the case of a circuit capable of both transmission and reception, such as the structure of the active network 225 as shown in FIG. 5, the circuit formed on the upper side is the receiving end (unsigned), and the circuit formed on the lower side is the transmitting end (unsigned). , The receiving end and transmitting end circuits are connected to a common terminal by a switch (225-6).

The active network 225 is a low noise amplifier (LNA: Low Noise Amplifier) (225-1) for removing the noise of the received signal and amplifying the weak signal in the case of a combined transmission/reception circuit that can be used for both transmission and reception. ), Attenuators (or Gain Controll 225-2) for adjusting (or attenuating) the gain of the received signal, and a phase shifter for shifting (adjusting) the phase of the received signal. (Phase Shifter) (225-3), and converts a serial signal from an external controller into a parallel signal to control a gain control attenuator (or gain control unit) 225-2 and a phase adjustment phase shifter (225-3) SPI (Serial to Parallel Interface) (225-4) for output, and an output amplifier (PA: Power Amplifier) (225-) to amplify a high-power signal to radiate a transmission signal to an external free space. 5) and a switch 225-6 for switching the path of the transmit/receive signal.

If necessary, the active network 225 includes an LNA (225-1) for noise removal and signal amplification, a phase shifter (225-3) and an SPI (225-4) for adjusting the phase. In addition, it may additionally include an attenuator (or gain control unit) 225-2 for gain control.

On the other hand, if the active network 225 is for transmission only, the gain control attenuator (or gain control unit) 225-2, the phase adjustment phase shifter 225-3, the SPI 225-4 and signal amplification It may be made to include an output amplifier (225-5).

The LNA (225-1) is a low-noise amplifier to amplify the weak signal received from the antenna to minimize amplification, and the attenuator (or gain control unit) 225-2 transmits an RF signal. In this case, by controlling the gain of the transmitted signal to adjust the beam shape of the antenna so that the signal is not radiated in an unwanted direction, the phase shifter 225-3 shifts the phase of the RF signal and radiates from the antenna. It is for adjusting the direction of the beam.

When receiving the RF signal, the switch 225-6 connects an incoming signal from Rx In (reception input) to a common terminal, and when transmitting, is active to send a signal of the common terminal to Tx Out (transmission output). Connect to the transmitting end of the network.

The present invention has been described in detail so far, but the embodiments mentioned in the process are merely illustrative, and it is clear that it is not limited, and the present invention is the technical spirit or field of the present invention provided by the following claims. Within the scope of not deviating from, it will be said that component changes to the extent that they can be dealt with equally fall within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Antenna radiator 2 Substrate 1 (εr=3)
3: Ground plate 4: Substrate 2 (Pre-preg, εr = 3.79)
5: Substrate 3 (εr=3) 6: Open coupling feed slot
7: Power distributor
10: antenna of the present invention
100: radiating part
110: radome (εr = 2 ~ 2.5) 120: radiating element
200: laminated substrate 300: air layer ((εr = 1)
210: first substrate 220: second substrate
230: third board
211: first dielectric (εr = 4.5) 212: first ground
213: first slot 214: DC voltage application unit
221: second dielectric (εr = 3.48) 222: second ground
223: second slot 224: power distribution
225: active network
224-1: RF input section 224-2: RF output section
225-1: LNA 225-2: Attenuator (gain control unit)
225-3: phase shifter 225-4: SPI
225-5: output amplifier 225-6: switch
231: 1st Pre-preg (εr=2.35) 232: Control logic line part
233: 2nd Pre-preg (εr = 2.35)

Claims (8)

A radiating part comprising a radome of dielectric constant and a plurality of radiating elements arranged by printing of an LDS plating process on any one or more of the top surface or the bottom surface of the radome;
A laminated substrate portion formed of a plurality of substrates to apply an RF feed signal to each radiating element of the radiating portion; And
The radiating portion and the stacked substrate portion are formed spaced apart at regular intervals, the spaced apart antenna is formed with an array of radiating elements in the radome, characterized in that formed as an air layer. The method according to claim 1, The laminated substrate portion,
An intermediate layer comprising a first dielectric having a dielectric constant and a first ground of a metal layer formed on an upper surface of the first dielectric and having a plurality of first slots for opening-coupled feeding of a feed signal to the radiating element of the radiating portion A first substrate;
A second dielectric having a dielectric constant as an intermediate layer, and a plurality of second slots formed on the upper surface of the second dielectric and opening and feeding a feed signal to the radiating element of the radiating portion, are formed in the first ground. A second substrate comprising a second ground of the metal layer formed to be one-to-one; Antenna comprising an array of radiating elements formed on the radome, characterized in that it comprises a. The method according to claim 2,
The first substrate further includes a DC voltage application part formed on a lower surface of the first dielectric and formed of a metal layer having a line for applying a DC voltage to an active element formed on the laminated substrate part,
The second substrate is formed on the lower surface of the second dielectric, an antenna having an array of radiating elements formed on a radome, further comprising a power distributor formed of a metal layer that applies a feed signal to each radiating element of the radiating portion. . The method according to claim 3,
The laminated substrate portion,
The second substrate further includes an active network formed of a plurality of active elements capable of adjusting the phase of each of the plurality of radiating elements arranged,
And a third substrate disposed between the first substrate and the second substrate, the third substrate having a control logic line unit for logically controlling each of a plurality of active elements provided in the active circuit of the second substrate. An antenna having an array of radiating elements formed on a radome. The method according to claim 4,
The plurality of active circuits of the active network,
An antenna having an array radiating element formed on a radome, comprising a phase shifter for shifting a phase, an LNA for removing noise and amplifying a signal, and an SPI for controlling the phase shifter. The method according to claim 5,
The radiating elements arranged in plural by the printing of the LDS plating process on any one or more of the upper or lower surfaces of the radome, the phase is adjusted by the phase shifter of the active network to form a 3D beam. The antenna having an array of radiating elements is formed on the radome, characterized in that. The method according to claim 4,
An antenna having an array of radiating elements formed on a radome, characterized in that the DC voltage application unit of the first substrate and the control line linear portion of the second substrate are disposed at right angles to each other. The method according to claim 1,
The radiating element arranged in plural by the printing of the LDS plating process on any one or more of the upper or lower surface of the radome is characterized in that it is either a rectangular microstrip patch element or a circular microstrip patch element. An antenna having an array of radiating elements formed on a radome.

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