TECHNOLOGY: MEANT FOR MASS PRODUCTION...
Since its inception, HUBER+SUHNER metallized plastic technology has incorporated large volume, low-cost and well-established manufacturing technological steps, such as injection molding (IM), physical vapor deposition coating (PVD) and soldering (e.g., reflow soldering including solder paste application and inspection). Due to complete ownership of the three technologies and their joint optimization, HUBER+SUHNER could revise all its core manufacturing steps when moving from the communication segment to the automotive market with its stringent lifetime and reliability requirement (e.g., extended temperature and humidity ranges, increased number of cycles).
This level of expertise is matched by a proprietary design for manufacturability.16,17 To ensure the use of the manufacturing technologies mentioned above, the complex 3D RF geometries are separated into several different layers, paying close attention to both RF performance and the manufacturability.
For example, the waveguides, designed to support the TE10 mode and created by joining different layers, are split across at the maximum of the E-field, corresponding at the null of surface current.18 This enables a high performance, robust, easy to implement and energy leakage-free assembly. This design approach, together with a proprietary coating, leads to losses as low as 8 to 10 dB per meter with no cross coupling between adjacent channels.
Finally, drawing on its experience, as previously described, HUBER+SUHNER developed a complete RF testing station that can verify all RF channels in a matter of seconds.
Figure 11 shows the process flow of a typical manufacturing line for metallized plastic technologies that provides a modular approach to fit different customer needs.
TECHNOLOGY: ...WHILE BEING AGILE
The availability and the use of mass production equipment may endanger the agility required in a product development program, especially when introducing the latest technologies into a new market. Indeed, validating complex and challenging product design iterations requires fast and simple manufacturing technologies.
HUBER+SUHNER masters 3D printing technology and rapid IM (i.e., using aluminum tools) to produce individual plastic layers while maintaining an in-house dedicated prototype shop for coating and soldering. Such know-how and capability enables the production of individual samples for concept studies and validation purposes, along with small series production, to match product development requirements, timing and cost. The challenge, thus the art, lies in the implementation of a solution that is as close as possible to series production, even at the earlier stages of product development. HUBER+SUHNER controls the complete value chain from polymer granulates to final validated product (see Figure 12).
MASS PRODUCTION: TODAY AND BEYOND
The demand for automotive radar antennas shows no signs of slowing. Driver assistance functions are increasingly coming to the fore, whether it is an emergency brake assistant, adaptive cruise control or even autonomous driving. To meet this increasing demand, HUBER+SUHNER implemented high volume production technologies that incorporate a high degree of automation from the start.
In addition to the first highly automated production line for long-range radar antennas in Switzerland, a short-range radar production line was recently set up at the HUBER+SUHNER premises in Poland. As a next step, matching customer and market requirements, production lines could be implemented at HUBER+SUHNER locations in other key markets such as China and America. Doing so allows production close to customers’ sites, minimizing the product-related CO2 footprint.
HUBER+SUHNER metallized plastic technology is revolutionizing the automotive radar world for all radar applications (long-, mid- and short-range, corner and side-looking radars) as it enables the achievement of very low insertion loss, improved efficiency, pattern stability and impedance bandwidth. It offers overwhelmingly higher performance compared to PCB antennas, with competitive manufacturing costs. Particularly, very low routing losses (less than 8 to 10 dB per meter) enable the distribution of antenna arrays quite freely over a large aperture, enabling high angular resolution and increased virtual array possibilities.
Based on more than a decade of experience and applications into multiple markets, HUBER+SUHNER 3D antennas for radar applications are meeting the demands by major OEMs and Tier-1 suppliers for increased waveguide antenna performance.1,2
- “HUBER+SUHNER Becomes Supplier of Radar Antennas to Leading Tier 1 Automotive Supplier,” HUBER+SUHNER AG, September 2021, Web: https://www.hubersuhner.com/en/company/media/news/2021/09/2021-09-30-en.
- “Advanced Radar Sensor – ARS540,” Continental Automotive, Web: https://www.continental-automotive.com/en-gl/Passenger-Cars/Autonomous-Mobility/Enablers/Radars/Long-Range-Radar/ARS540.
- “Wireless Ethernet Bridge SENCITY ®LINK SL60,” HUBER+SUHNER AG, 2010, Web: https://www.hubersuhner.com/en/documents-repository/markets/pdf/automotive/wireless-ethernet-bridge-sencity-link-sl60.aspx.
- “SENCITY® Matrix Flat Antennas,” HUBER+SUHNER AG, July 2017, Web: https://5.imimg.com/data5/NE/EW/KK/SELLER-948981/huber-sencity-matrix-directional-wave-outdoor-antenna.pdf.
- “Fixed Radio Systems; Characteristics and Requirements for Point-to-Point Equipment and Antennas; Part 4-2: Antennas; Harmonized EN covering the essential requirements of article 3.2 of R&TTE Directive,” ETSI, Final draft ETSI EN 302 217-4-2 V1.4.1, November 2008, Web: https://www.etsi.org/deliver/etsi_en/302200_302299/3022170402/01.04.01_40/en_3022170402v010401o.pdf.
- Terragraph, Web: https://terragraph.com/.
- U. Hugel, R. Glogowski, M. Thiel and F. Merli, “Adapter with Waveguide Channels and Electromagnetic Band Gap Structures,” European Patent Office, Patent No. EP3430685, 2020.
- A. Post, “An Antenna Concept that Addresses the Challenges with Automotive Radar,” IWPC Trends in Automotive Radar and Impact on System Architecture, Workshop Presentation, March 2016.
- F. Merli and A. Post, “Injection Molded Radar Antennas,” IWPC 2018 New Features for Automotive Radars, Workshop Presentation, January 2018.
- J. Hasch, E. Topak, R. Schnabel, T. Zwick, R. Weigel and C. Waldschmidt, “Millimeter-Wave Technology for Automotive Radar Sensors in the 77 GHz Frequency Band,” IEEE Transactions on Microwave Theory and Techniques, Vol. 60, No. 3, March 2012, pp. 845–860.
- F. Merli and A. Post, “Injection Molded Radar Antennas,” IWPC 2021 In Search of Optimum Automotive Sensor Solutions, Workshop Presentation, May 2021.
- F. Merli, A. Garcia-Tejero and M. Kagelmann, “3D Waveguide Antenna Radar Systems - an RF Independent Substrate Solution,” IWPC 2022 Which Direction is Automotive Radar Heading?, Workshop Presentation, April 2022.
- R. Schnabel, D. Mittelstrab, T. Binzer, C. Waldschmidt and R. Weigel, “Reflection, Refraction, and Self-Jamming,” IEEE Microwave Magazine, Vol. 13, No. 3, May 2012, pp. 107–117.
- J. Kowalewski, A. Garcia Tejero, P. Romano, M. Pieper, E. Willmann, M. Notter, F. Merli, A. Freni and A. Mazzinghi, “Antenna Device for Radar Applications,” European Patent Office Patent 2022/063535, 2021.
- A. Garcia-Tejero, J. Kowalewski, F. Rodriguez Varela, A. Freni, A. Mazzinghi and F. Merli, “Three Advances in Metallized Polymer mmWave Waveguide Antenna Design,” 2021 IEEE APS/URSI, Workshop Presentation, December 2021.
- A. Garcia-Tejero, P. Romano and F. Merli, “Antenna Device,” European Patent Office Patent 2021/081922. 2020.
- R. Glogowski, “Array Antenna,” CH Patent 00825/16, 2016.
- H. Butterweck, “Mode Filters for Oversized Rectangular Waveguides,” IEEE Transactions on Microwave Theory and Techniques, Vol. 16, No. 5, May 1968, pp. 274–281.