Aster SATCOM-On-The-Move (SOTM) Terminal Family
Overview:
SDI's Aster is a line of bespoke military SATCOM-On-The-Move (SOTM) terminals purpose-designed for the AetherNet VLEO constellation. The family spans five orders of magnitude in radiated power and three orders of magnitude in antenna aperture, from a 95-gram wearable patch worn under body armor to a 385 kilogram shipboard array capable of sustaining 40 Gbps aggregate throughput to a carrier strike group. Every terminal in the family shares a common waveform architecture, cryptographic framework, and software-defined modem core, enabling seamless interoperability across the full range of military platforms, from a dismounted special-operations soldiers to a nuclear aircraft carrier. Despite spanning a wide range of sizes and capabilities, all Aster terminals share same architectural elements. Every Aster terminal uses an active electronically scanned array (AESA) operating at 47.2–48.2 GHz (downlink) and 42.0–42.5 GHz (uplink), with dual circular polarization. The array is constructed from tiled subarrays of identical 4×4-element GaN-on-Diamond MMIC modules, enabling scalability from 16 elements (A10) to 16,384 elements (A20) using the same qualified building block. A common FPGA-based modem core implements the AetherNet OFDMA waveform with adaptive modulation (QPSK to 1024-QAM), LPI/LPD spread-spectrum and frequency-hopping modes, and the military-unique burst-mode transmission scheduler. The SDM is firmware-upgradeable in the field via AetherNet over-the-air update. For communication security every Aster terminal contains an Type 1 encryption module (Suite B / CNSA 2.0 algorithms) with hardware root of trust, secure boot, and tamper-detection zeroization. A secondary commercial-grade AES-256-GCM engine handles non-classified traffic on separate key material. An embedded AI processor (an neural-network accelerator with 2–50 TOPS depending on terminal tier) manages satellite acquisition, predictive handoff, adaptive modulation selection, interference detection, and anti-jam beam steering autonomously, with no operator intervention required. All terminals use standard 10/25/100 GbE Ethernet interfaces (depending on tier) to the host platform’s tactical network, with built-in HAIPE-compatible encryption and IPv6/MPLS encapsulation for integration with existing network infrastructure.
Product Family Overview:
The Aster family comprises eight terminal models, designated A10 through A120, where the number indicates the antenna aperture diameter in centimeters. Each model is optimized for a specific set of platforms and operational scenarios, while sharing the common Aster architecture.
Model Aperture Elements Tx Power Mass Downlink rate Uplink Rate Primary Platform A10 10 cm 16 (4×4) 2 W 95 g (antenna) + 180 g (modem) 150 Mbps 25 Mbps Soldier wearable / SOF A15 15 cm 64 (8×8) 5 W 320 g (integrated) 500 Mbps 150 Mbps Manpack / UAS Group 3 A20 20 cm 256 (16×16) 10 W 1.8 kg 2 Gbps 500 Mbps Platoon hub / UAV A30 30 cm 576 (24×24) 25 W 4.5 kg 5 Gbps 1.5 Gbps Light Vehicle (4x4) A45 45 cm 1,024 (32×32) 50 W 12 kg 10 Gbps 3 Gbps Aircraft / large UAS A60 60 cm 2,304 (48×48) 100 W 30 kg 20 Gbps 6 Gbps Ship (frigate/destroyer) A90 90 cm 4,096 (64×64) 200 W 85 kg 30 Gbps 10 Gbps Ship (cruiser/amphib) A120 120 cm 16,384 (128×128) 500 W 385 kg 40 Gbps 15 Gbps Supercarrier/BMD
Common System Design:
The fundamental building block of every Aster antenna is a hermetically sealed, 25 mm × 25 mm multi-chip module containing 16 dual-polarization V-band radiating elements, 16 GaN transmit power amplifiers (125 mW per element), 16 low-noise amplifiers (3.5 dB noise figure), 16 digital phase shifters (6-bit, 5.6° resolution), and the associated bias and control circuitry. The tile is manufactured using a GaN-on-Diamond MMIC process at a commercial foundry, with wafer-scale testing ensuring > 99% element yield. The Aster antenna is assembled by populating a printed-circuit-board (PCB) motherboard with the required number of tiles modules. The A10 uses a single tile (16 elements); the A120 uses a 1,024-tile array (16,384 elements). This modular approach is designed to enable dramatic cost reduction through volume manufacturing. Each Aster terminal contains an embedded neural-network accelerator that manages the unique challenges of VLEO SOTM operations. At 200 km altitude, each satellite is visible for only 90 to 180 seconds and crosses the sky at angular rates up to 3°/second. The AI processor must perform satellite acquisition within 100 ms, execute predictive make-before-break handoffs every 3 to 5 seconds with less than 0.5 ms data-gap, continuously adapt modulation and power to compensate for atmospheric conditions and platform motion, and detects and mitigates jamming, all simultaneously and without operator intervention. The total AI compute requirement scales from 2 TOPS for the smallest A10 terminal (which handles only basic acquisition and handoff) to 50 TOPS for the A120 (which runs all functions simultaneously across 16,384 elements, including constellation-level multi-satellite MIMO coordination). The AI accelerator is implemented as ab edge inference chip: the SDI Lattice Nano (25 TOPS, 5 W) for A10 through A30, and the SDI Lattice (275 TOPS, 25 W) for A45 through A120.
Tile Parameter Value Notes Dimensions 25 × 25 × 3.8 mm Including BGA substrate Elements per Tile 16 (4×4 lattice) Dual circular polarization Element Spacing 5.6 mm (≈0.9λ at 47.5 GHz) Supports ±60° scan capability Tx Power per Element 125 mW (+21 dBm) GaN-on-Diamond PA PA Efficiency 35% (PAE) At P1dB, 47.5 GHz Rx Noise Figure 3.5 dB Integrated LNA Phase Shifter Resolution 6-bit (5.6° steps) Digital MMIC phase shifter Amplitude Taper Range 10 dB For adaptive sidelobe control Control Interface SPI (10 MHz) Per tile address, 4-wire bus DC Power per Tile 720 mW (Tx), 280 mW (Rx) Active per-element power gating Mass per Tile 4.2 g Including BGA solder Reliability (MTBF) 2 × 10⁶ hours Per tile; graceful degradation
SDM Function Implementation Performance Waveform Engine OFDMA with 2,048 subcarriers, 960 kHz spacing 2 GHz instantaneous bandwidth Modulation Support QPSK, 8-PSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM Adaptive per subcarrier per frame Channel Coding LDPC (rate 1/4 to 9/10) + polar codes for control <0.5 dB of Shannon limit MIMO Processing Up to 2×2 spatial multiplexing (A30 and larger) >2X peak throughput Spread Spectrum Mode Direct-sequence, 127-chip Gold code 20 dB processing gain for LPI/LPD Frequency Hopping 10,000 hops/s across 2 GHz V-band Anti-jam, pseudo-random pattern Burst Mode 50–200 ms transmit bursts, AI-scheduled Covert LPI/LPD communications Doppler Compensation Real-time tracking ±600 kHz; < 10 Hz residual LEO-specific pre-compensation Handoff Processing Predictive make-before-break; < 0.5 ms gap Satellite pass every 3–5 seconds Beamforming Computation IDigital beamforming for all elements Update rate of 10,000 beam updates/s Interface 10/25/100 GbE (model dependent) SFP28 optical
AI Function Algorithm Computing Requirement Latency Satellite prediction + acquisition Orbital mechanics + ML correction 0.5 TOPS 50 ms initial, 5 ms update Predictive handoff LSTM trained on pass geometry 0.2 TOPS Pre-computed 30 s ahead Adaptive modulation control (AMC) Reinforcement learning on CSI 0.3 TOPS Per-frame (125 μs) Interference detection + classification CNN on spectral snapshots 1.0 TOPS < 50 ms detection Anti-jam beam steering Real-time null optimization 2.0 TOPS < 125 μs (1 OFDMA frame) Platform motion compensation IMU fusion + Kalman filter 0.1 TOPS 1 kHz update rate Atmospheric attenuation estimation Physics-informed ML on beacon SN 0.1 TOPS 1 Hz update Link-health monitoring + built-in-test Autoencoder on RF chain telemetry 0.2 TOPS Continuous