The overall objective of the activity was the design of a Q/V-band gateway antenna that can be scaled in the range 7 to 13 meters for future feeder link gateways and which uses the same feed in all antenna configurations. The mechanical, electrical and RF designs should reach at least PDR level and the designed antenna should offer a high Q/V-band EIRP on the ground and a high efficiency in reception.
To optimally cover the aforementioned range of diameters, on the one hand HITEC´s existing high-performance 6.8m Ka-band design was upgraded and qualified for Q/V-band operation by incorporating a Q/V-band RF system and on the other hand the scalability has been demonstrated by the design of a new 11m Q/V-band antenna reusing the same RF system.
The key challenges in this project were three-fold:
- Reduction of the ohmic losses in interconnections between feed and amplifiers, which often scale with antenna size.
- Optimization of the reflector shape and main reflector surface accuracy as well as tracking accuracy which play a particularly important role at such high frequencies.
- Identification of a complete set of suitable COTS RF components to reduce risks on programmatic scheduling.
The 6.8m Q/V-band antenna design, which has been adapted from the existing 6.8m Ka-band antenna design, is not only high-TRL and ready for commercialization but has also a track record of outstanding pointing and tracking capabilities, even under high wind loads. Transfer of the underlying proven design principles and user-friendly features to the larger, 11m antenna type has led to a new design which will also achieve outstanding pointing and tracking performance. A unique solution has been developed for minimizing interconnect losses and making them virtually independent of antenna size. The 11m antenna has been specifically designed as a stand-alone system, able to incorporate all equipment inside the antenna structure without need for any additional infrastructure on the field.
6.8m antenna design:
11m antenna design:
The Q/V-band gateway antennas designed for this activity contain the following main subsystems, with the components they comprise:
- Radio-frequency (RF) subsystem
- Motion control subsystem
- HITEC local monitoring & control (M&C) subsystem
- Electrical subsystem
- Mechanical subsystem
The following figure illustrates the product breakdown structure including major components.
The project plan for the activity foresaw the following main tasks:
- Task 1: Component market study & refinement of the antenna specifications
- Task 2: Trade-off analysis and update of the performance budgets
- Task 3: Design of a 6.8m Q/V-band limited motion antenna
- Task 4: Design of an 11m Q/V-band limited motion antenna
- KOM in April 2018
- Trade-Off Analysis Review (TAR) in December 2019 (completion of tasks 1 and 2)
- Mid Term Review (MTR) in May 2020 (completion of task 3)
- Final Review (FR) and Final Presentation (FP) in October 2021 (completion of task 4 and the project)
The project has been successfully completed. A reference model for the intended application has been established in terms of frequency plan and redundancy. Critical trade-offs have been carried out and optimized solutions for Q/V-band have been derived. HITEC Luxembourg´s existing 6.8m Ka-band antenna design has been adapted and qualified for Q/V-band, resulting in a design that is high-TRL and ready for commercialization. A new 11m antenna design has been developed specifically for Q/V-band applications up to PDR-level maturity.