CN115395221B - Ultra-wideband integrated antenna for electromagnetic environment monitoring - Google Patents

Abstract

The invention relates to an ultra-wideband integrated antenna for electromagnetic environment monitoring, which comprises a first frequency range antenna, a second frequency range antenna, an active amplifier and a selector switch, wherein the first frequency range antenna is connected with the second frequency range antenna through the active amplifier; the first frequency range antenna and the second frequency range antenna are connected with the active amplifier through radio frequency lines to form a first frequency range active antenna and a second frequency range active antenna, and the first frequency range active antenna and the second frequency range active antenna are connected with the selector switch through the radio frequency lines to realize the switching of the antennas. The invention has the advantages that the impedance bandwidth of the antenna is widened, the gain is improved and the miniaturization of the antenna is realized by measures of conical feed, parasitic structure increase, three-point feed, angle cut and the like and a method of connecting the antenna with an active amplifier. And the fast switch realizes the fast switch of the working frequency band between 1MHz and 1GHz and between 1GHz and 18GHz, so that the antenna can carry out the real-time monitoring of the full frequency band.

Description

An ultra-wideband integrated antenna for electromagnetic environment monitoring

technical field

The invention relates to the technical field of antennas, in particular to an ultra-wideband integrated antenna for electromagnetic environment monitoring.

Background technique

The development of modern science and technology makes all kinds of electrical and electronic equipment widely used in national defense science and technology construction and production and life. While bringing great convenience to people, some useful or useless electromagnetic energy generated by these equipment will put people in a In the increasingly complex electromagnetic environment; the pros and cons of the electromagnetic environment will affect other surrounding equipment and systems, and electromagnetic radiation pollution has been listed as the fourth largest pollution. For radio equipment, by collecting and recording the spectrum information in the environment And energy distribution can guide the use of equipment to ensure that each equipment can be put into use normally.

Considering the different pollution sources, such as amateur radio working on MF and HF; FM radio and TV working on VHF; radar, mobile communication and satellite communication working on UHF and SHF, therefore, it is necessary to carry out electromagnetic pollution in a very wide frequency band. environmental monitoring. Antennas are an important part of electromagnetic environment monitoring equipment, so it is particularly important for the design of ultra-wideband antennas. At present, most UWB antennas are mainly designed to cover the specified frequency band of 3.1GHz-10.6GHz. This is because the size of the antenna is comparable to the wavelength. Therefore, how to achieve impedance bandwidth coverage of the entire frequency band through one antenna, such as 1MHz- The frequency range of 18GHz needs to be considered at present.

It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to those of ordinary skill in the art.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art, and provide an ultra-wideband integrated antenna for electromagnetic environment monitoring, which solves the problems of incomplete frequency band coverage, poor gain and large size of the existing ultra-wideband antenna.

The purpose of the present invention is achieved through the following technical solutions: an ultra-wideband integrated antenna for electromagnetic environment monitoring, which includes a first frequency range antenna, a second frequency range antenna, an active amplifier and a switch; the first frequency range The antenna and the antenna of the second frequency range are connected with the active amplifier through the radio frequency line to form the active antenna of the first frequency range and the active antenna of the second frequency range, and the active antenna of the first frequency range and the active antenna of the second frequency range are connected through the radio frequency line Connect with the switch to realize the switching of the antenna;

The first frequency range antenna includes a first dielectric substrate, a U-shaped radiation patch arranged on the front of the first dielectric substrate and a first ground plate arranged on the back of the first dielectric substrate; the bottom of the U-shaped radiation patch is connected to There is a first tapered feed structure for feeding; an elliptical slot is cut in the middle of the first grounding plate, and a parasitic structure is added in the middle area of the elliptical slot, and multiple resonance frequency points are formed through the parasitic structure.

The first tapered feed structure includes a first feeder segment, a second feeder segment, a third feeder segment and a feeder offset segment; one end of the first feeder segment is connected to the bottom of the U-shaped radiation patch, and the other end is connected to the second Two feeder segments; the second feeder segment is connected to the feeder offset segment in a way of cornering to one side, and the feeder offset segment is connected to the third feeder segment in a way of downward cornering.

The width of the first feeder segment is smaller than the width of the third feeder segment; the second feeder segment is a tapered structure with successively larger widths, and the width of the junction with the first feeder segment is the same as the width of the first feeder segment, The width of the joint between the second feeder segment and the third feeder segment is the same as that of the third feeder segment, and also forms a tapered structure as a whole, and the impedance bandwidth of the antenna is widened by changing the current path through the tapered structure.

A first chamfer is cut at the outer corners of the second feeder section and the feeder offset section, and the outer corners of the feeder offset section and the third feeder section, and the impedance bandwidth of the antenna is widened by changing the current path through the first chamfer; The parasitic structure is composed of two upper semi-ellipse and lower semi-ellipse with different sizes, the minor axis of the upper semi-ellipse coincides with the major axis of the lower semi-ellipse.

The second frequency range antenna includes a second dielectric substrate, a rectangular radiation patch disposed on the front of the second dielectric substrate, and a second ground plate disposed on the back of the second dielectric substrate;

The bottom of the rectangular radiating patch is connected to a second tapered feed structure for feeding; the second grounding plate is arranged at one end of the back of the second dielectric substrate, and is connected to the upper left and upper right corners of the second grounding plate. The rounded corners are processed to improve the matching performance of the antenna.

The second tapered feed structure includes a tapered feed line and a three-point feed structure, the width of the tapered feed line becomes larger in turn; the three-point feed structure is arranged at the bottom of the radiation patch, and the three-point feed structure and the tapered The end of the feeder line with the smaller width is connected.

Both the lower left corner and the lower right corner of the rectangular radiation patch are rounded, and three equally spaced grooves are cut in the middle of the bottom of the rectangular radiation patch; the three-point feeding structure includes three etc. Wide feeder lines, three equal-width feeder lines are respectively embedded in three grooves, forming three intersecting feed points with the rectangular radiation patch, and the equal-width feeder lines on the left and right are respectively connected to the middle corner The equal-width feeder is connected, and a second cut angle (18) is cut outside the corner, and the equal-width feeder in the middle is connected with the tapered feeder.

The length l3 of the first feeder segment=15mm, the length l4=14.1mm of the second feeder segment, the length l5=2mm of the third feeder segment, the length offset=18mm of the feeder offset segment; the first cut angle Length r_cut=3mm, width w3=1.5mm of the first feeder segment, width w2=3.1mm of the third feeder segment; the major axis a11=237.3mm and the minor axis a1=172.3mm of the elliptical slit; the upper The coincident axis b1 of the half ellipse and the lower half ellipse = 104.4mm.

The length of the tapered feeder hl_feed1=11.3mm, the width of one end of the tapered feeder is 0.9mm, and the width of the other end is 2.1mm; the radius of the fillet is 14.3mm, and the width of the equal-width feeder is 0.9mm. The length of the chamfer is 0.5mm.

The operating frequency range of the first frequency range antenna includes 1 MHz-1 GHz, and the operating frequency range of the second frequency range antenna is 1 GHz-18 GHz.

The present invention has the following advantages: an ultra-broadband integrated antenna for electromagnetic environment monitoring, which widens the antenna through measures such as tapered feed, increased parasitic structure, three-point feed, corner cutting, and the method of connecting with an active amplifier Impedance bandwidth is wide, the gain is improved, and the miniaturization of the antenna is realized. And through the fast switching switch, the working frequency band can be quickly switched between 1MHz-1GHz and 1GHz-18GHz, so that the antenna can perform real-time monitoring of the whole frequency band.

Description of drawings

Fig. 1 is a schematic structural diagram of a wideband antenna of the present invention;

Figure 2 is a schematic structural diagram of the back of the broadband antenna;

Fig. 3 is a schematic diagram of a partial enlargement of the front of the broadband antenna and the first tapered feed structure;

FIG. 4 is a schematic structural diagram of an ultra-wideband antenna;

Fig. 5 is a structural schematic diagram of the back of the ultra-wideband antenna;

Fig. 6 is a schematic diagram of a partial enlargement of the front of the ultra-wideband antenna and the second tapered feed structure;

7 is a schematic diagram of the principle of an active amplifier;

FIG. 8 is a schematic diagram of S parameters of a wideband antenna;

Fig. 9 is the radiation pattern of the bandwidth antenna at 0.1GHz and 0.3GHz;

Figure 10 is the radiation pattern of the bandwidth antenna at 0.5GHz and 0.7GHz;

FIG. 11 is a schematic diagram of S parameters of an ultra-wideband antenna;

Figure 12 is the radiation pattern of the ultra-wideband antenna at 1GHz and 2GHz;

Figure 13 is the radiation pattern of the ultra-wideband antenna at 4GHz and 6GHz;

Figure 14 is the radiation pattern of the ultra-wideband antenna at 8GHz and 10GHz;

Figure 15 is the radiation pattern of the ultra-wideband antenna at 12GHz and 14GHz;

Figure 16 is the radiation pattern of the ultra-wideband antenna at 16GHz and 18GHz;

In the figure: 1-U-shaped radiation patch, 2-first dielectric substrate, 3-first grounding plate, 4-first tapered feed structure, 5-first feeder segment, 6-second feeder segment, 7 -Third feeder segment, 8-feeder offset segment, 9-first cut corner, 10-elliptical slot, 11-parasitic structure, 12-rectangular radiation patch, 13-second dielectric substrate, 14-second connection Floor, 15-second tapered feed structure, 16-conical feeder, 17-equal width feeder, 18-second cut corner.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only It is a part of the embodiments of this application, not all of them. The components of the embodiments of the application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the application provided in conjunction with the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application. The present invention will be further described below in conjunction with the accompanying drawings.

The present invention specifically relates to an ultra-wideband integrated antenna for electromagnetic environment monitoring, which includes a first frequency range antenna, a second frequency range antenna, an active amplifier and a switch; the first frequency range antenna and the second frequency range antenna The active antenna of the first frequency range and the active antenna of the second frequency range are formed by connecting the active amplifier with the radio frequency line, and the active antenna of the first frequency range and the active antenna of the second frequency range are connected with the switching switch through the radio frequency line to realize the antenna switch.

As shown in Figures 1 and 2, the first frequency range antenna is a bandwidth antenna operating in the frequency range of 1MHz-1GHz, which includes a first dielectric substrate 2, and a U-shaped radiation patch 1 arranged on the front of the first dielectric substrate 2 and the first ground plate 3 arranged on the back of the first dielectric substrate 2; the bottom of the U-shaped radiation patch 1 is connected with a tapered feed structure 4 for feeding;

Further, an elliptical slot 10 is cut in the middle of the first grounding plate 3 , and a parasitic structure 11 is added in the middle area of the elliptical slot 10 , and multiple resonant frequency points are formed through the parasitic structure 11 .

Further, the parasitic structure 11 is composed of two upper semi-ellipse and lower semi-ellipse with different sizes, the minor axis of the upper semi-ellipse coincides with the major axis of the lower semi-ellipse.

Wherein, the major axis a11 of the elliptical slit 10=237.3mm, the minor axis a1=172.3mm; the axis b1=104.4mm where the upper half ellipse and the lower half ellipse overlap, and other parameters of the parasitic structure are c1=65mm, c2 = 39mm.

As shown in Figure 3, the tapered feed structure 4 includes a first feeder section 5, a second feeder section 6, a third feeder section 7 and a feeder offset section 8; one end of the first feeder section 5 is connected to the U-shaped radiation The bottom of the patch 1, the other end is connected to the second feeder segment 6; the second feeder segment 6 is connected to the feeder offset segment 8 in a way of cornering to one side, and the feeder offset segment 8 is connected to the third feeder segment in a downward corner 7 connections. Wherein, the angle of the corner is 90°.

Further, the width of the first feeder segment 5 is smaller than the width of the third feeder segment 7; the second feeder segment 6 is a tapered structure with successively larger widths, and the width of the connection with the first feeder segment 5 is the same as that of the first feeder segment. The width of the segment 5 is the same, the width of the connection between the second feeder segment 6 and the third feeder segment 7 is the same as that of the third feeder segment 7, and a tapered structure is also formed on the whole, and the current path is changed to widen through the tapered structure Impedance bandwidth of the antenna; a chamfer 9 is cut at the outer corners of the second feeder segment 6 and the feeder offset segment 8, and the feeder offset segment 8 and the third feeder segment 7, and the current path is widened by changing the current path through the trimmer 9 The impedance bandwidth of the antenna.

Wherein, the length l3=15mm of the first feeder section 5, the length l4=14.1mm of the second feeder section 6, the length l5=2mm of the third feeder section, the length offset=18mm of the feeder offset section 8; the cut angle The length r_cut of 9 is 3 mm, the width w3 of the first feeder segment 5 is 1.5 mm, and the width w2 of the third feeder segment 7 is 3.1 mm.

Among them, the upper end of the U-shaped radiation patch 1 is two rectangles whose length is l1=67.4mm, and the middle part of the patch is a large semi-ellipse minus a small semi-ellipse, wherein the parameters rr1=41.9mm, rr2= 82.8 mm, rr11 = 42.1 mm, rr22 = 82.7 mm.

The material of the first dielectric substrate 2 of the first frequency range antenna is Fr4, the thickness h_sub=1.6mm, the relative permittivity ε _r =4.4, and the loss tangent tanδ=0.02. The design size of the final antenna is l_sub×w_sub×h_sub=532.8mm×400mm×1.6mm, where l_sub, w_sub and h_sub are the length, width and thickness of the first dielectric substrate 2 respectively.

The antenna in the first frequency range applies excitation to the bottom end of the feeder through side feeding, so that the radio frequency electromagnetic field is excited between the U-shaped radiation patch 1 and the ground plate 3, and passes through the gap between the patch and the ground plate 3 to the outside radiation.

As shown in Figure 4 and Figure 5, the second frequency range antenna is an ultra-wideband antenna working in the 1GHz-18GHz frequency range, which includes a second dielectric substrate 13, a rectangular radiation patch 12 arranged on the front of the second dielectric substrate 13 and a second ground plate 14 disposed on the back of the second dielectric substrate 13;

Further, the bottom of the rectangular radiation patch 12 is connected with a second tapered feed structure 15 for feeding; the second ground plate 14 is arranged at one end of the back of the second dielectric substrate 13, wherein the second ground plate 14 remains The length is hh_ground=12.3mm, the width is hw_ground=38mm, and the upper left corner and the upper right corner of the second ground plate 14 are cut with a radius of hr_cut1=14.3mm to improve the matching performance of the antenna.

As shown in Figure 6, the second tapered feed structure 15 includes a tapered feed line 16 and a three-point feed structure, the width of the tapered feed line 16 becomes larger in turn; the three-point feed structure is arranged at the bottom of the radiation patch 12, The three-point feed structure is connected to the narrow end of the tapered feed line 16 .

Further, the lower left corner and the lower right corner of the rectangular radiation patch 12 are rounded, and three equally spaced grooves are cut in the middle of the bottom of the rectangular radiation patch 12; the three-point feeding structure Including three equal-width feeders 17, the three equal-width feeders 17 are respectively embedded in three grooves, and form three intersecting feed points with the rectangular radiation patch, and the equal-width feeder lines 17 on the left and right sides respectively extend to the middle corner The way is connected with the equal-width feeder 17 in the middle, and a second cut corner 18 is cut outside the corner, and the middle equal-width feeder 17 is connected with the tapered feeder 16 .

The material of the dielectric substrate selected for the antenna in the second frequency range is Arlon TC350, the thickness hh_sub=1.016mm, the relative permittivity ε _r =3.5, and the loss tangent tanδ=0.002; the design size of the final antenna is hl_sub×hw_sub×hh_sub= 62.8mm×42.3mm×1.016mm. Wherein hl_sub, hw_sub, hh_sub are the length, width and thickness of the second dielectric substrate 13 respectively.

Wherein, the length hl_feed1=11.3mm of tapered feeder 16, the width of one end of tapered feeder 16 is 0.9mm, and the width of the other end is 2.1mm; hw_feed=0.9mm, the distance between the tapered feeder 16 and the bottom of the second dielectric substrate 13 hl_feed0=0.9mm, the length of the second cut angle is h_cut=0.5mm, the cut groove depth hl_slot=1mm, the equal width feeder 17 and the concave The distance between both sides of the slot hw_slot=0.3mm is to change the current path to widen the impedance bandwidth. The specific gas parameters of the antenna in Figure 5 are hw_feed2=0.8mm, hw_feed3=1mm, hh_feed1=1.1mm, hl_feed2=7mm, hl_feed3=0.7mm .

The antenna in the second frequency range adopts a coaxial feeding method, so that a radio frequency electromagnetic field is excited between the rectangular radiation patch 12 and the second ground plate 14, and passes through the surrounding area between the rectangular radiation patch 12 and the second ground plate 14. The gaps radiate outward.

As shown in Figure 7, the active amplifier is connected to the broadband antenna and the ultra-wideband antenna to further widen the bandwidth of the antenna and increase the gain of the antenna. The active amplifier adopts a three-stage amplifier, and some of its parameters are shown in the following table:

model Two-stage amplification Three levels of amplification Working frequency(MHz) 1-1000 1-1000 Gain(dB) 30 45 Noise figure (dB) 4 4 Output P-1(dBm) ≥13 ≥13 Working voltage (V) 6-15 6-15 Current (mA) 130 200

As shown in FIG. 8 , the broadband active antenna satisfies S ₁₁ <-10dB within the frequency range of 1MHz-1GHz, so its impedance bandwidth covers 1MHz-1GHz. Figure 9 and Figure 10 show the radiation patterns of the antenna at 0.1GHz, 0.3GHz, 0.5GHz, and 0.7GHz. After finally connecting to the amplifier, the maximum gain of the broadband active antenna is 11.55dB, which meets the design requirements.

As shown in FIG. 11 , the UWB active antenna satisfies S ₁₁ <-10dB within the frequency range of 1GHz-18GHz, so its impedance bandwidth covers 1GHz-18GHz. As shown in Figure 12-Figure 16, the radiation pattern of the antenna at 1GHz, 2GHz, 4GHz, 6GHz, 8GHz, 10GHz, 12GHz, 14GHz, 16GHz, 18GHz, the maximum gain of the ultra-wideband microstrip antenna is 11dB, which meets the design requirements .

The above descriptions are only preferred embodiments of the present invention, and it should be understood that the present invention is not limited to the forms disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and Modifications can be made within the scope of the ideas described herein, by virtue of the above teachings or skill or knowledge in the relevant art. However, changes and changes made by those skilled in the art do not depart from the spirit and scope of the present invention, and should all be within the protection scope of the appended claims of the present invention.

Claims (10)

1. An ultra-wideband integrated antenna for electromagnetic environment monitoring is characterized in that: the antenna comprises a first frequency range antenna, a second frequency range antenna, an active amplifier and a change-over switch; the first frequency range antenna and the second frequency range antenna are connected with the active amplifier through radio frequency lines to form a first frequency range active antenna and a second frequency range active antenna, and the first frequency range active antenna and the second frequency range active antenna are connected with the selector switch through radio frequency lines to realize the switching of the antennas;

the first frequency range antenna comprises a first dielectric substrate (2), a U-shaped radiation patch (1) arranged on the front surface of the first dielectric substrate (2) and a first grounding plate (3) arranged on the back surface of the first dielectric substrate (2); the bottom of the U-shaped radiating patch (1) is connected with a first conical feed structure (4) for feeding; an oval gap (10) is cut in the middle of the first grounding plate (3), a parasitic structure (11) is added in the middle area of the oval gap (10), and a plurality of resonant frequency points are formed through the parasitic structure (11).

2. The ultra-wideband integrated antenna for electromagnetic environment monitoring as claimed in claim 1, wherein: the first conical feed structure (4) comprises a first feed section (5), a second feed section (6), a third feed section (7) and a feed offset section (8); one end of the first feeder line section (5) is connected with the bottom of the U-shaped radiation patch (1), and the other end of the first feeder line section is connected with the second feeder line section (6); the second feeder section (6) is connected to the feeder offset section (8) in a sideways corner and the feeder offset section (8) is connected to the third feeder section (7) in a downwards corner.

3. An ultra-wideband integrated antenna for electromagnetic environment monitoring according to claim 2, characterized in that: the width of the first feeder section (5) is smaller than the width of the third feeder section (7); the second feeder line section (6) is of a conical structure with the width gradually increased, the width of the connection part of the second feeder line section (6) and the first feeder line section (5) is the same as that of the first feeder line section (5), the width of the connection part of the second feeder line section (6) and the third feeder line section (7) is the same as that of the third feeder line section (7), the conical structure is also formed on the whole, and the impedance bandwidth of the antenna is widened by changing the current path through the conical structure.

4. An ultra-wideband integrated antenna for electromagnetic environment monitoring according to claim 2, wherein: cutting first cut angles (9) at outer corners of the second feeder line segment (6) and the feeder line offset segment (8) and the third feeder line segment (7), and changing a current path through the first cut angles (9) to widen the impedance bandwidth of the antenna; the parasitic structure (11) comprises an upper semi-ellipse and a lower semi-ellipse which are different in size, and the short axis of the upper semi-ellipse is coincident with the long axis of the lower semi-ellipse.

5. The ultra-wideband integrated antenna for electromagnetic environment monitoring as claimed in claim 1, wherein: the second frequency range antenna comprises a second dielectric substrate (13), a rectangular radiation patch (12) arranged on the front surface of the second dielectric substrate (13) and a second grounding plate (14) arranged on the back surface of the second dielectric substrate (13);

the bottom of the rectangular radiation patch (12) is connected with a second conical feed structure (15) for feeding; the second grounding plate (14) is arranged at one end of the back face of the second dielectric substrate (13), and corner cutting processing is carried out on the upper left corner and the upper right corner of the second grounding plate (14) so as to improve the matching performance of the antenna.

6. An ultra-wideband integrated antenna for electromagnetic environment monitoring according to claim 5, characterized in that: the second conical feed structure (15) comprises a conical feeder (16) and a three-point feed structure, and the width of the conical feeder (16) is increased in sequence; the three-point feed structure is arranged at the bottom of the radiating patch (12) and is connected with one end of the tapered feeder line (16) with small width.

7. The ultra-wideband integrated antenna for electromagnetic environment monitoring as claimed in claim 6, wherein: the left lower corner and the right lower corner of the rectangular radiation patch (12) are processed by cutting round corners, and three grooves which are arranged at equal intervals are cut in the middle position of the bottom of the rectangular radiation patch (12); the three-point feed structure comprises three equal-width feed lines (17), the three equal-width feed lines (17) are respectively embedded into the three grooves and form three crossed feed points with the rectangular radiation patch, the equal-width feed lines (17) positioned on the left side and the right side are respectively communicated with the equal-width feed line (17) positioned in the middle in a mode of turning towards the middle, a second cut angle (18) is formed in the outer side of the corner in a cutting mode, and the equal-width feed line (17) in the middle is connected with the conical feed line (16).

8. An ultra-wideband integrated antenna for electromagnetic environment monitoring according to claim 4, characterized in that: the length l3=15mm of the first feeder segment (5), the length l4=14.1mm of the second feeder segment (6), the length l5=2mm of the third feeder segment, the length offset =18mm of the feeder offset segment (8); the length r _ cut =3mm of the first chamfer (9), the width w3=1.5mm of the first feeder segment (5), and the width w2=3.1mm of the third feeder segment (7); the major axis a11=237.3mm and the minor axis a1=172.3mm of the elliptical slit (10); the upper and lower semi-ellipses have coincident axes b1=104.4mm.

9. An ultra-wideband integrated antenna for electromagnetic environment monitoring as claimed in claim 7, wherein: the length hl _ feed1=11.3mm of the tapered feed line (16), the width of one end of the tapered feed line (16) is 0.9mm, and the width of the other end is 2.1mm; the radius of the fillet is 14.3mm, the width of the equal-width feeder line (17) is 0.9mm, and the length of the second chamfer is 0.5mm.

10. An ultra-wideband integrated antenna for electromagnetic environment monitoring according to any of claims 1-9, characterised in that: the working frequency range of the first frequency range antenna comprises 1MHz-1GHz, and the working frequency range of the second frequency range antenna is 1GHz-18GHz.

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