Ku-Band antenna Switching Module(KSM)
Delivered high-precision, real-time control for Ku-Band antenna and RF systems in defence satellite communication
Industry: Defence Satellite Communication
Why PSU’s Choose GD:
Our client selected General Datum for our end-to-end embedded expertise in delivering a complex, multi-board control system under tight timelines. We provided high-speed PCB design, firmware, and custom GUI with precise GPIO control and Ethernet communication.
The complete solution was delivered in just 3 months, meeting Class-2 standards and stringent defence-grade reliability requirements.
Challenge:
PSU required a robust control system capable of managing phase shifters and attenuators across multiple Antenna and RF cards (in 4×4 or 8×8 configurations) with precise timing. The system needed to handle multiple polarization modes (V, H, LHCP, RHCP), seamless TX/RX switching, and reliable read/write operations on RF card EEPROMs — all while maintaining stable performance through an Ethernet-connected control architecture.
Additionally, the Antenna card and RF card incorporated several high-performance RF ICs with varying control interfaces, power requirements, and switching characteristics:
ADRF5020 (Analog Devices – Broadband SPDT Switch)
MQS-0518SM (Marki Microwave – 5 GHz to 18 GHz 90° splitter/combiner)
ADRF5044 (Analog Devices – Broadband SP4T Switch)
AWMF-0147 (Qorvo – 13.75–14.5 GHz Ku-Band Quad 4×2 Tx Beamformer)
Coordinating control signals across these diverse ICs while meeting stringent timing constraints posed a significant design challenge.
Solution:
General Datum delivered a complete end-to-end embedded solution, measuring around an 8-layer KSM control card (160×120 mm) interfaced via an Ethernet hub to manage multiple antenna and RF boards. Our scope covered component selection, circuit design, controlled impedance PCB layout (90/100 Ω differential), procurement, fabrication, SPI-based firmware, and a custom GUI for real-time control and EEPROM programming. The system generated precise GPIO signals for polarization and TX/RX modes while addressing challenges like GPIO current drop and timing across high I/O counts.
To manage the diverse RF ICs (ADRF5020, MQS-0518SM, ADRF5044, AWMF-0147), we implemented a daisy-chain control topology. This reduced routing complexity, enabled efficient signal cascading, and ensured synchronized operation across all components—meeting the critical 200 µs timing requirement.
Key Results for KSM:
Achieved precise real-time control of phase shifters, attenuators, and polarization modes with reliable SPI communication.
Developed an 8-layer PCB with controlled impedance routing compliant with Class-2 defence standards.
Built an intuitive GUI for seamless TX/RX control, GPIO management, and EEPROM operations.
Ensured stable Ethernet communication between the GUI and control hardware under operational conditions.
Enabled synchronized control of diverse RF ICs via a daisy-chain topology, achieving ≤ 200 µs response time.
Demonstrated glitch-free operation across all polarization modes (V, H, LHCP, RHCP) with smooth TX/RX transitions.
Delivered a scalable and stable architecture supporting 4×4 and 8×8 configurations with low latency and high signal integrity.
The Ku-band antenna switching module significantly enhanced PSU’s defence SATCOM systems by enabling fast, accurate, and reliable beam control in a compact, scalable design.