3D printing antenna

How To 3D Print Your Own Working Antennas

It Works, and You Can Do It!

What RF engineer has not thought about 3D printing an antenna? It’s a natural combination of RF curiosity and and basic 3D printing capabilities. You have probably even seen social media photos and posts about this achievement. But do these antennas work? Has anyone properly tested them? Is it even practical with simple materials and processes?

Download files for all 8 antennas: STL files are in THIS zipped archive, and SketchUp  files are in THIS zipped archive (created with the free Sketchup Make 2017).

So we decided to give it a try ourselves, and also to add some value to the conversation. We are a professional antenna testing service with an RF anechoic chamber. We can build, optimize, and fully evaluate 3D antenna prints to answer these fundamental questions. In the end, it turned out to be quite practical, but not without a trashcan full or horns and lots of trial and error.

In the spirit of true science, we wanted to create plastic horns that could be tested against their commercial all-metal counterparts. So we chose to 3D print, metalize, and test the family of 15 dBi standard gain horns. Their simple rectangular horn shape design is decades old, and their standard geometries have very predictable gain. These “waveguide” horns have readily available coax launches (adapters) easily found surplus, purchased new, or even 3D printed. Despite their simplicity, commercial standard gain horns are expensive, normally priced from $500 to $1500. Contrast this to a spray metalized 3D print costing a dollar!

We limited our scope to the 2-40 GHz frequency range. This will entirely encompass the practical limits of common 3D filament printing. In the S Band (2-4 GHz), the standard gain 15 dBi horn is the size of a salad bowl, and required our large format printer. It could also be printed in parts and glued together from smaller prints. In the Ka band (26-40 GHz) the same 15 dBi horn will fit into the palm of your hand, and would challenge the tolerances of most typical 3D printers. Above 40 GHz, test equipment gets very expensive and parts get impractically small for casual experimenters.

Metalization

We chose MG Chemicals’ shielding spray paints for metalization because they are easy to buy (even on Amazon) and simple to use. Our first test antenna was an X band horn (8-12 GHz) with an easy to print 4 inch aperture. Two copies were printed to evaluate two common paints: “841 Super Shield™ Nickel” and “843AR Super Shield™ Silver Coated Copper”. Each was given two spray coats with drying time in between.

Disappointment !

The spec sheets for both paints showed impressive surface conductivity numbers and the metalized horns simply looked great! You can see the gain results in the horn shown in the left of Figure 3. We had high expectations. However, when patterned in the anechoic chamber, the results were terrible. Forward gain was only about 5 dBi, as opposed to the expected 15 dBi. But examining the test results showed that something was actually working. Both antennas had directivity of about 15 dB and the expected 30 degree beamwidths. Since return loss was “great” (> 20 dB), the only explanation was that the metalization’s realized surface conductivity was poor, causing the horns to suffer about 10 dB of internal loss.

Pre-Testing with VSWR

We devised a simple bench test to prove out this theory and to “pre test” antennas for this kind of loss. You should utilize this very useful approach, since not everyone has their own free-space antenna testing lab. Measuring the return loss (VSWR) of an antenna is the most common performance test (and does not require an anechoic chamber). The rule of thumb is that high return losses of more than 10 dB point to a “good” antenna. The thinking is that 90% or more of transmitted energy sent to the “good” antenna will radiate because it does not reflect back to the source. This is normally a useful test, when you can assume your antenna has small or zero losses. However a lossy antenna, or even a “dummy load” also has great return loss too!

Consider the low return loss from a short circuit. If you short a coaxial cable or the aperture of a low loss metal horn antenna, you can also expect a low return loss (large reflection). We verified these low return losses on “shorted” lab grade commercial horn antennas by covering their apertures with aluminum cooking foil. The same shorted aperture test on the 3D printed horns showed large (> 20 dB) return losses, indicating they were better attenuators than antennas!

In the figure below you can see that the “smoothed” surface antenna showed the desired low return losses. While there is some ripple due to the imperfect cooking foil “short” on the horn, the important thing to look for is some frequencies of low (approximately 1 dB) return loss. This could not happen if the inside surface of the antenna were lossy.

Despite the shiny appearance of the metalized paint, and the near-zero ohm meter resistance readings, surface resistance was the only possible loss mechanism. The tiny surface ripple artifacts of the 3D printing layers are small compared to the relatively large operating wavelength (1 inch at X Band). However, surface smoothing did eventually prove to be the key to removing this loss and achieving the target 15 dBi gain across the whole 2-40 GHz test range. But even applying multiple “liberal” coats of conductive paint did not sufficiently lower this loss without prior smoothing.

Surface Preparation

Sanding is an obvious way to smooth the 3D layer surface roughness. It works well, but it is time consuming. The horn’s funnel shape also creates triangular facets that are enclosed and tapered making power sanding tools impractical. After experimentation, we found that “solvent smoothing” was the most time effective and least effort. Acetone is a well known and useful solvent for ABS plastic prints, and it worked nicely on prints from our smaller ABS filament printer. Our large format printer only uses PLA filament, which did not seem to have a readily available solvent. However, a little research uncovered dichloromethane (methylene chloride) and a gallon was purchased on Amazon. It was highly effective at softening and smoothing the surface roughness on PLA plastic.

Chemical Safety

Both solvents are hazardous, but dichloromethane is especially poisonous. It has historically been the key ingredient in common paint stripper, but is being phased out due to its toxicity when used for DIY home projects. After some trial and error, we found the following process worked well. The resulting smoothed surface is shown in the right of the figure above.

Work outdoors, since “adequate ventilation” is NOT practical indoors. You will still need a respirator mask that is rated for organic solvents (commonly available for “oil” based painting). Use full length chemical gloves that are specifically rated for your solvent, and protect these delicate chemical gloves by also wearing “work gloves” over top of them. You must also wear eye protection, since you WILL be splashing and brushing solvent.

Solvent Smoothing

We found it convenient to pour solvent into a common metal paint-roller tray and use this to brush on, scrub, and re-catch the solvent as in this figure. Disposable bristle brushes are best along with metal kitchen pot scrubbing pads. Don’t use plastic brushes or the green/blue plastic kitchen scrub pads, since the dichloromethane will soften them. It takes only a minute to smooth the inside of even the largest horn with the pot scrubber (or steel wool) if it is kept wet with solvent. A round bottle brush also easily scrubbed the waveguide portion of the horn. There is no need to smooth or metalize the outside of the horn, just work the inside surfaces and mating flange.

If you are assembling a larger antenna from smaller prints, now is the perfect time to “solvent weld” the already softened parts. Press and hold them together for about a minute while the solvent evaporates.

Applying the conductive spray paint is straightforward, proceed as you would spray paint any object. It is best done outdoors too, holding it in one hand with a glove allowing easy reorientation to get at all inside surfaces and the flange. Excess paint is simply shaken off. Two coats were always used and worked well.

Epoxy Coating (Painting)

There is a second practical option available for surface smoothing.  You can cover the rough 3D printed surface with a paint-on two-part epoxy coating. We tried “XTC-3D” from smooth-on.com, and it worked well for prints from 2 to 18 GHz. Some optional quick pre-sanding before application removes “large” high spots from rough surfaces. However, post sanding is not optional. The cured shiny surface looks great, but will not accept the metalized paint until lightly sanded. While less work than sanding smooth a rough 3D print, you will not be able to avoid this step. Any unsanded sections of “shiny” epoxy will not accept the metalization paint. We found inside corners to be problematic. In this photo, you can see blue plastic peeking through the conductive paint where the epoxy was not completely sanded. In horns from 18 to 40 GHz, the wave-guide features were just too small for the relatively thick coating. Critical dimensions were distorted, and holes and inside radiuses were starting to get filled in. However, antennas are quite tiny at these frequencies and you can smooth them quickly with small hobby files. There is really no need for solvent or epoxy coatings for antenans this small.

Metalized Coating Choices

The nickel version of the paint seemed to have several dB of loss at all frequencies despite surface smoothing. The chart below shows the nickel paint’s “performance hit” (surface loss) even in the S-band.

Luckily, the silver/copper version spray shielding paint worked well up to 26 GHz. But from 26 to 40 GHz the tiny Ka horn still displayed about 3 dB loss by having only 12 dBi of gain (even when solvent smoothed). This was easily solved by sanding the horn completely smooth with a tiny file, and repainting it. Since this Ka band horn is only an inch in size, its soft plastic walls were trivial to file smooth in just a minute. This extra smoothing step allowed it to display very low shorted aperture return loss on the bench and fully restored its expected 15 dBi gain in the chamber, as pictured above.

Conclusions

Yes, you can 3D print your own working microwave antennas using common materials and your “home-brewing” skills. Just smooth the active surfaces with solvent, sanding, epoxy, or filing then use our recommended conductive paint. If you can check the shorted aperture return loss / VSWR and verify that it has at least some frequencies of low return loss (less than 1 dB), you can reasonably expect the same antenna performance as a solid metal antenna. Complex shapes can be accommodated by splitting 3D prints into sections that allow for sanding/smoothing access before assembly by gluing or solvent welding. You can make various “cavity” electromagnetic parts like wave guides or coax-adapters this way. The conductive spray paint easily flows over and obscures surface sanding scratches and seams.

Results

The graph above shows how good these horns can be. It compares a lab grade Waveline Model 299 Standard Gain Horn Antenna (15 dBi S Band model) and two 3D printed exact copies. The plastic versions were printed in PLA, solvent smoothed, and spray painted as described here. All three antennas were tested using the same Waveline Model 201NF Coax Adapter. The copper/silver painted 3D printed antenna’s gain was only +/- 0.2 dB different from the commercial horn antenna, well within measurement repeatability. The third curve on this graph shows the other identical printed antenna with two coats of the nickel based conductive coating. This formulation displays about 0.5 dB less gain, and gets worse by up to 5 dB at 10 GHz. The graph below shows the measured gain of our entire family of 15 dBi horns from 2 to 40 GHz, all hitting their gain targets.

If you would like to experiment further, we have made the STL printable files available for download. All 3D designs were done with “SketchUp Make 2017”, a free 3D CAD design tool. The SketchUp files for these horns are also downloadable here if you would like to edit the geometries. Links are below …

Download the SketchUp 3D-model files here

Download the 3D printable STL files here

An Overview of 3D Printed Antennas for 5G Communications and Beyond

Henry Giddens, and Yang Hao, Queen Mary University of London

IEEE Future Networks Tech Focus, Volume 4, Issue 1, November 2020

Abstract

5G communication systems will once again revolutionize the ways that people connect and communicate with each other. Future mobile networks will also span new frequency bands in mm-wave and THz bands. The combination of the need to wirelessly connect everyday consumer devices to the internet, and the range of new frequency bands on offer, has necessitated research into new antenna systems. One technology that is enabling the realization of a new class of antennas is 3D printing. This has been fueled in part by the rise of new antenna design techniques such as transformation optics and topological optimization, whilst further developments in new filament materials designed specifically for electromagnetic applications means complex antenna geometries can now be easily realized. This article presents an overview of the ways in which additive manufacturing is enabling the development of novel antennas for 5G wireless networks and beyond.

1. Introduction

The 5th generation of mobile communications will once again offer vast improvements in bandwidth and coverage, which will translate into a user experience of fast download speeds and an uninterrupted connection to the network. The antennas used in these networks will need to facilitate these features whilst maintaining low profile and conformal physical dimensions so that they can be included in consumer devices and access points. At the mm-wave bands, directive communications is essential to overcome the higher path loss and steerable beams will be required to communicate with mobile targets. Future communication networks will look to utilize even high frequencies, approaching the THz bands and sub-millimeter wavelengths. Antennas will also have to support wide input-impedance bandwidths, whilst maintaining good radiation efficiency and reliable radiation patterns. In this article we look at how 3D printing is addressing these issues. The rapid rise and falling cost of 3D printing technology over the last 10 years has generated a growing industry estimated to be worth over $10 billion in 2020 [1]. In technology-focusses industries this has manifested itself in small-scale manufacturing and rapid prototyping of new de- vices. In recent years, antenna research has taken advantage of the possibilities offered by additive manufacturing techniques. For example, antennas with complex spacial material profiles can now be realized with various 3D printing techniques. Furthermore, new design techniques for conformal antennas such as transformation optics and multi-objective topological optimization are being utilized which are particularly suited   to generating printable antennas [2], [3]. Metallic printing has allowed engineers to manufacture new types of antennas up to THz frequencies, whilst 3D printing has also contributed to the realization of microwave metamaterial antennas.

2. Materials and Printing Techniques

A number of 3D printing techniques have been used for printing antenna and electromagnetic structures. These include fused deposition modeling (FDM), also known as fused filament fabrication (FFF), Polyjet printing, stereo lithography (SLA), micro-SLA and photonic polymerization. Each method has advantages and trade-offs which are suited to manufacturing different types of antennas. For example, FDM, where filament materials are extruded from a heated nozzle, is generally the cheapest 3D printing technique available, whilst it also benefits from a wide variety of filaments and can print with multiple materials in a single print. The SLA and polymerization techniques use laser or UV light to cure resin materials into the desired 3D shape. As a result, they can achieve a much higher resolution when compared to FDM, down to the 10s of nanometers scale. They are better suited   to fabrication of smaller structures, and therefore are used to fabricate antennas operating in mm-wave and THz frequency bands. The materials used in these printers are essentially a light curable resin, and subsequently cannot be modified to the extent that FDM filaments have been.

3D printing has most commonly been used for manufacturing dielectric-based antennas. This is due to the fact that printing dielectric materials is far easier than printing conductive filaments. Dielectric materials can be printed using fused deposition modeling (FDM) 3D printers that can be purchased for just a few hundred dollars, whilst standard filament materials such as ABS (Acrylonitrile butadiene styrene, a common thermoplastic) and PLA (polylactic acid, a biodegradable thermoplastic polyester) have been shown to have low dielectric losses up to 100s of GHz [4]. Furthermore, specialized dielectric filaments are available for electromagnetic (EM) applications with tailored dielectric constants up   to a value of 12 [5]. Fig. 1 shows the measured dielectric properties of a selection of Preperm filaments for two mm- wave frequency bands, 70-110 GHz and 220-320 GHz. All filaments are stable with frequency and the losses only become significant for the highest permittivity materials when the frequency exceeds 200 GHz.

Figure 1. Measured relative permittivity and loss tangent of electromagnetic dielectric filaments available from PREPERM [5] at mm-wave frequencies. The filaments were printed using a Prusa i3 MK3s 3D printer into 20 x 20 mm samples with 100% fill factor and measured using a quasi-optical transmissometer. The shaded area shows the error boundary associated with the measured data.

Antennas with gradient-index material profiles (i.e. materials that have spatially varying dielectric properties) are uniquely suited to 3D printing for a number of reasons.  From the effective-medium theory it is possible to predict the effective permittivity of a volume of material where only a percentage of that volume is filled with a dielectric filament, and the rest of the volume by air. 3D printed dielectric metamaterials can easily be printed to obtain precise effective permittivity, and this can be further varied throughout the total volume of the antenna to obtain graded-index materials so long as the unit cell dimensions are significantly smaller than the wavelength. Multi-material 3D printing can be used to extend both the range and steepness of the dielectric gradient which opens up new possibilities in the antenna design [6].

3. Dielectric Antennas

Due to the ease of printing dielectrics compared to conductive materials, 3D printing is best suited to fabricating dielectric antennas such as lenses and DRAs. Lens have been demonstrated using almost all the common 3D printing methodologies spanning a wide range of frequencies from microwaves through the mm-wave bands and up to THz. Lens antennas are particularly suited to mm-wave 5G frequency bands as they generate directive radiation, are not physically large due to the small wavelength, and can also have beam steerable capabilities, whilst the wavelength is not so small as to be beyond the resolution of FDM 3D printers. The Luneburg lens for example, is a multi-focal lens able to concentrate a plane wave impeding on any surface to a point on the opposite surface of the lens, requires a material profile with permittivity of 2 in the center and 1 on the surface [7], as shown in Fig. 2 (a - c). Whilst the Luneburg lens has been known to optical engineers since it was proposed by Rudolf Luneburg in 1944, 3D printing has offered a simple solution for easy fabrication. In order to adapt the Luneburg lens and make it more practical for real-world applications, various geometrical modifications to the Luneburg lens have been demonstrated through trans- formation optics coordinate transformations. These include the Gutman lens Fig. 2 (d-f) [8], the compressed Luneburg lens Fig. 2 (g - j) [9], and the flat Luneburg lens [10]. Each of these modifications requires a more complex material profile, however they can be realized using the 3D printing techniques previously described. Each modification to the Luneburg lens importantly retains the key feature of generating directive, steerable beams which are necessary for 5G mm-wave and future THz communication links. Fig. 2 shows some examples of the various Luneburg Lenses which have been 3D printed for mmWave beam scanning applications. The lenses are often excited using traditional antenna elements such as patches, waveguide probes and horns, with the lens taking the role of shaping and steering the antenna beam.

Lens antennas at THz frequencies will form a key element in THz communication systems as they are wideband devices and generate the directive beams necessitated by the small wavelength and high path loss. 3D printed THz lenses have been demonstrated through micro SLA 3D printing, which are able to print with sub-micron resolution [11] that is require to generate graded-index interfaces at THz wavelengths. A number of diffractive lenses operating at 0.625 THz were demonstrated in [12] using low cost 3D printing techniques.

3D printing has also been use to realize antennas in specialist radios where customized designs are required. For example, an 8-beam lens operating in military mobile-adhoc networks with multi-functionality and 360° coverage was presented in [6]. The lens, shown in Fig. 3, is able to radiate with an optimized 45° beamwidth in each of its 8 sectors, but can switch to multi-beam mode covering 8 directions in any one instance due to the symmetry of the lens. The lens was 3D printed using multi-material printing with a permittivity gradient ranging from 3. 6 on the edge to 1 in the center, and takes a conformal octagonal shape.

Dielectric resonator antennas offer unique advantages over traditional antennas, such as a reduced size whilst maintaining a wide input impedance bandwidth and good radiation efficiency, which can be beneficial to 5G communications networks. 3D printing has also opened up new possibilities    in dielectric resonator antenna research. For example, the gradient-index DRA presented in [13] and shown in Fig. 4 excites three transverse modes which are merged together to provide a wide input impedance bandwidth from 4 - 8 GHz. 3D printed DRA arrays have also been demonstrated as high- gain access point antennas [14], and the technology has been further applied to mm-wave frequencies [15].

Figure 2. An overview of beam steerable 3D printed lens antennas for mmWave communications. (a) - Permittivity distribution of a classic Luneburg lens antenna [7]. (b) - Photograph of 3D printed Luneburg Lens antenna using effective medium theory. (c) - Measured radiation patterns at 28 GHz with feed position at 0◦, 90◦, -90◦, and 180◦. (d) - Permittivity distribution of the Gutman lens with the focal point moved to a position of 0.45R [8]. (e) Photograph of the 3D printed Gutman lens at 60 GHz. (f) - Simulated electric field patterns showing beam steering as the feed position is moved along the flat face of the lens. (g) - Permittivity distribution of a compressed Luneburg lens [9]. (h) - photograph of the 3D printed compressed Luneburg lens at 84 GHz. (i) - Setup for multi-material 3D printing of the compressed lens with 5 different filaments. (j) - Measured radiation patterns of the compressed lens at 84 GHz. All measurements and fabrication of lens antennas performed at Queen Mary University London.

Figure 3. 3D-printed 8-beam dielectric lens antenna with multi-functionality including optimized 45° radiation pattern [6].

Figure 4. A graded-index 3D-printed dielectric resonator antennas with 3 transverse modes and wide input impedance bandwidth [13].

4. Metallic Antennas

Most traditional antenna structures require a conductive element in order to interface with the input port and provide resonance. 3D printing conductive materials for electromagnetic applications remains a challenging problem for a number of reasons. Poor conductors, which are acceptable for 3D printed electronic circuits, are not suited to antenna applications as the losses severely impact radiation efficiencies. However, conductive filaments have recently become commercially available which may offer some potential, such as the Multi3D Electrificonductive filament with a quoted volume resistivity of 0.006 Ω cm [16]. For purely metallic antennas, specialist metal 3D printers are an alternative option. These can directly print the metallic materials including aluminum, steel, titanium and cobalt through direct metal laser sintering (DMLS). For example, Jun et. al. 3D printed fractal monopole antennas (Fig. 5) using metal AM which have ultra-wideband radiation characteristics and geometries that would be difficult to realize using subtractive manufacturing methods [17]. Metallic printing has also been used to fabricate horn antennas and waveguides at 110-170 GHz [18], although surface roughness and layer height can become an issue at submillimeter wavelengths. Metallic printing is likely to be widely utilized to fabricate mmWave and THz antennas that required intricate 3D geometries that traditional techniques are incapable of achieving.

Figure 5. Fractal monopole antenna using metallic AM technology [17].

An alternative and cost effective approach for 3D printing metallized antenna parts is to print using a regular filament   or resins, and then coat the parts in conductive materials [19–22]. This allows the intricate and detailed 3D shapes associated with additive manufacturing techniques to be incorporated into antenna technologies, has a much lower material cost than pure metal antennas, and has other advantages in terms of weight [21]. 4 different coating techniques, Jet Metal Processing (JMT), aerosol spray coating using copper and nickel conductive paints, and brush painting with electrolube silver conductive paint, were analyzed in [20]. JMT is able to achieve performance comparable to PEC antennas at both 10 GHz and 30 GHz. Metal-coated 3D printed parabolic mirrors have also been demonstrated with nanometer scale surface roughness for THz applications [22]. Low cost metallization techniques clearly offer possibilities for mass production of low cost 3D printed antennas for 5G, mm-wave and THz communications.

5. Metamaterials

Metamaterials are artificially designed periodic structures which can be designed to have properties which are not found in naturally occurring materials. Electromagnetic metamate- rials have been demonstrated with negative refractive index components for applications such as cloaking. Metamaterials can also be utilized in more practical applications including wireless communication. 3D printing is a valuable tool for further innovation in this field, as it allows multiple materials to be combined in complex structures that will give an optimal material response. For example, a chequerboard dielectric metamaterial with anisotropic properties was 3D printed in [23] using two high-contrast dielectric filaments. The authors in [24] 3D printed a broadband microwave metamaterial with customized permittivity and permeability using the electrificonductive filament.

6. Summary

In summary, it is clear that 3D printing has already had a significant impact on antenna related research and development. With incoming 5G networks and trends for future communications systems moving to higher frequencies, additive manufacturing technology will become increasingly important to the industry. It is expected that widely available and low cost 3D printing techniques, such as FDM and SLA, as well as the more specialist additive manufacturing methods, including Nano-scale photonic printers and metallic 3D printing, will all contribute to the continued development and manufacture of novel antennas for wireless networks.

References

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Biography

Yang Hao is a Professor of Antennas and Electromagnetics at Queen Mary University of London. He also serves in the management team of Cambridge Graphene Centre since 2013. He is active in a number of areas, including computational electromagnetics, microwave metamaterials and transformation optics, antennas and radio propagation for body centric wireless networks, active antennas for millimeter/sub-millimeter applications and photonic integrated antennas. He co-published two books: “Antennas and Radio Propagation for Body-Centric Wireless Communications”, and “FDTD modelling of Metamaterials: Theory and Applications”. He has published more than 200 journal papers and is a frequent keynote speaker for many conferences. Prof. Hao was the Editor-in-Chief for the IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS. He founded a new open access journal and is now the Editor-in-Chief of EPJ Applied Metamaterials.
He won 2015 IET AF Harvey Research Prize and is a co-recipient of BAE Chairman’s Silver Award in 2014 and the Royal Society Wolfson Research Merit Award. Prof. Hao is an elected Fellow of Royal Academy of Engineering, IEEE and IET.
Professor Yang Hao received the Ph.D. degree from the Centre for Communications Research (CCR) at the University of Bristol, U.K. in 1998. From 1998 to 2000, he was a postdoc research fellow at the School of Electrical and Electronic Engineering, University of Birmingham, U.K.

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IEEE Future Networks Tech Focus Editorial Board

Rod Waterhouse, Editor-in-Chief
Mithun Mukherjee, Managing Editor
Imran Shafique Ansari
Anwer Al-Dulaimi
Stefano Buzzi
Yunlong Cai
Zhi Ning Chen
Panagiotis Demestichas
Ashutosh Dutta
Yang Hao
Gerry Hayes
Chih-Lin I
James Irvine
Meng Lu
Amine Maaref
Thas Nirmalathas
Sen Wang
Shugong Xu
Haijun Zhang

How we printed the antenna

Development of technology and prototype production of a broadband logarithmic microwave antenna using additive technologies (3D printing)

From the beginning, very briefly about who we are and what prompted us to start the topic of this publication.

We are a small engineering team with considerable experience in the development of passive radar systems, as well as looking for and finding areas for ourselves to apply and develop our skills. In general, we try not to stand still, but to invent and do.

More about the antenna. One day, during an impromptu brainstorming session, the idea came up to 3D print a broadband antenna. There is only one goal - to obtain technology, thanks to which it will be possible to manufacture antennas with very similar radio technical characteristics. With traditional manufacturing methods, the spread of antenna characteristics is quite significant from sample to sample, and this is important, especially in amplitude direction finding systems.

Next comes the formalized text from the report that we prepared based on the results of the work done.

General provisions

Existing manufacturing technologies do not provide the required identity of the radio parameters of antennas. The requirement of the identity of the radio engineering parameters of antennas in radar systems is especially important. The solution of the problem of identity is possible by manufacturing antennas with minimal technological tolerances. Modern additive technologies (3D printing) are best suited for this purpose. To do this, it was necessary to select an antenna production technology using additive technology, develop a 3D model, obtain the design characteristics of the antenna according to the model parameters, make an experimental batch of antennas, and conduct radio engineering measurements.