Using cutting-edge GaN technology, the new SSPA/BUC family offers outstanding performance in outdoor or indoor operations for civil applications
| Parameter | 250W | 500W |
|---|---|---|
| Frequency Range | 22.55 – 23.15 GHz | 22.55 – 23.15 GHz |
| Output Power (Psat) | 250 W | 500 W |
| Gain | >60 dB (typical) | >60 dB (typical) |
| Gain Flatness | ±1.5 dB | ±1.5 dB |
| Cooling | Liquid cooling | Liquid cooling |
| M&C Interface | RS-485, USB, Ethernet | RS-485, USB, Ethernet |
| Operating Temperature | -40°C to +55°C (outdoor) | -40°C to +55°C (outdoor) |
| Form Factors | Outdoor, Indoor (rack-mount) | Outdoor, Indoor (rack-mount) |
Contact Celestia TTI for complete specifications and custom configurations for specific mission profiles.
Human missions to the Moon require something that has never existed before at this scale: a reliable, high-capacity uplink from Earth ground stations to cislunar assets — orbiters, landers, surface habitats, and gateway platforms. The frequency band allocated internationally for this purpose is K band, specifically the 22.55–23.15 GHz uplink spectrum, designated by the ITU and the Space Frequency Coordination Group (SFCG) for Earth-to-lunar communications.
Celestia TTI’s K Band GaN SSPAs are purpose-engineered for this mission. Operating precisely within the ITU-allocated 22.55–23.15 GHz forward link band, these amplifiers provide the high output power and signal fidelity that ground stations supporting Artemis, Gateway, and commercial lunar programs demand. Available in 250W and 500W configurations with liquid cooling for continuous 24/7 operation, the K Band product family delivers the performance margins that mission-critical space infrastructure requires.
Operating at 22.55–23.15 GHz, the exact frequency range internationally coordinated for Earth-to-lunar forward links, ensuring regulatory compliance and interoperability with space agency ground networks.
Operation At K band frequencies and high output powers, thermal management is critical. The integrated liquid cooling system maintains stable operation during long uninterrupted tracking passes — essential for cislunar communications where contact windows cannot be interrupted.
Gallium Nitride semiconductor technology delivers the power density needed to reach 500W output at 22–23 GHz — a demanding frequency range where earlier solid-state technologies could not achieve competitive power levels.
Flexible deployment options allow installation directly at the antenna feed for maximum EIRP, or in climate-controlled equipment rooms with cabling to the dish — adapting to the infrastructure constraints of new lunar ground station builds or facility upgrades.
M&C capability via RS-485/USB, Ethernet with embedded web interface, Telnet, and SNMP for integration into ground station management systems and space agency network operations centres.
GaN solid-state design eliminates the consumable elements of tube amplifiers, delivering MTBF performance suited to infrastructure that must operate continuously across multi-year lunar programs with minimal maintenance windows.
Nearly three decades of specialist experience in high-power RF systems across space, defence, and telecommunications makes Celestia TTI a credible partner for the demanding requirements of lunar ground infrastructure — a market where engineering credentials matter as much as product specifications.
Developing GaN SSPAs that deliver hundreds of watts at 22–23 GHz requires mastery of millimetre-wave power combining, thermal management, and signal integrity at frequencies where component tolerances are measured in microns. Celestia TTI’s K Band product family is the result of this accumulated engineering capability applied to a new and strategically important application.
The liquid cooling systems integrated into K Band SSPAs reflect Celestia TTI’s systems engineering approach: thermal management is designed in from the start, not retrofitted. This enables the sustained, high-duty-cycle operation that cislunar ground stations require.
Manufactured in Spain under ISO 9001:2015 and ISO 9100:2018 certified quality management systems, K Band SSPAs meet the procurement standards of space agencies and institutional customers who require documented quality assurance and traceability throughout the supply chain.
Beyond standard 250W and 500W configurations, Celestia TTI’s engineering team works with customers on custom power levels, interface requirements, and system integration for specific ground station architectures. Lunar ground infrastructure is rarely a standard installation — Celestia TTI’s engineering collaboration model is designed for this reality.
Ground stations supporting NASA's Artemis crewed lunar programme require K band uplink capability to command and communicate with the Lunar Gateway, Human Landing Systems, and surface assets. Celestia TTI's 500W GaN SSPAs provide the output power and reliability that agency-grade infrastructure demands for mission-critical communications.
Commercial providers delivering payloads to the lunar surface under NASA's CLPS programme operate their own ground networks. K band SSPAs are essential for the command uplink chains that control landers and rovers during surface operations — a window that cannot be interrupted once a landing sequence begins.
The Lunar Gateway orbital platform requires continuous telemetry, tracking, and command support from Earth ground stations. Facilities building Gateway TT&C infrastructure need K band amplifiers capable of long uninterrupted operation tracks as the Gateway orbits the Moon on its near-rectilinear halo orbit.
As lunar traffic increases under both agency and commercial programmes, supplementary ground station networks are being built to increase contact coverage and redundancy. These facilities require K band uplink capability — from government-operated sites to commercial ground station providers offering services to lunar mission operators.
European and international lunar exploration programmes, including ESA's participation in the Artemis architecture and independent lunar initiatives from JAXA, ISRO, and others, require ground infrastructure compliant with internationally coordinated K band allocations. Celestia TTI's European manufacturing and ISO certifications position these SSPAs for agency procurement requirements across multiple space agencies.
Universities, research institutions, and technology developers testing lunar communication architectures, link budget demonstrations, and radio frequency propagation experiments across the cislunar medium require K band ground transmit capability. The 250W configuration provides a cost-effective entry point for laboratory and test facility installations.
The return of human presence to the Moon is not a single event — it is a sustained infrastructure programme spanning decades. From robotic precursor missions and commercial lunar payload deliveries to the Lunar Gateway orbital platform and eventual permanent surface outposts, every phase of cislunar activity depends on reliable, high-data-rate communications links between Earth and the Moon.
Why K Band for Earth-to-Lunar Uplinks
The ITU and the Space Frequency Coordination Group recommend K band for high data rate communications in the lunar region, with uplink frequency allocation at 22.55–23.15 GHz designated for Earth-to-lunar forward links — covering Earth-to-lunar orbit, Earth-to-lunar surface, and lunar orbit-to-surface communication scenarios. NASA’s common K band frequencies include 22.55–23.15 GHz for forward data or uplink, establishing this spectrum as the global standard for cislunar ground station infrastructure.
The physics behind this choice are straightforward. Higher frequencies allow narrower beams from a given antenna aperture, concentrating more energy toward the receiver across the ~384,000 km Earth-Moon distance. The 22.55–23.15 GHz allocation avoids the atmospheric water vapour absorption peak at 22.24 GHz that limits propagation in other parts of the K band spectrum, making it practical for ground-based transmission.
The Ground Station as Mission Infrastructure
Unlike commercial satellite communications where a degraded link means slower internet access, cislunar communications support life-critical functions: command and control of lunar landers, telemetry from astronaut life support systems, navigation data for vehicles on the lunar surface, and high-definition video from exploration operations. The ground amplifier at the heart of the uplink chain must perform without interruption.
Excessive thermal dissipation is one of the most challenging operational problems for high-power SSPAs in satellite earth stations, particularly in systems requiring continuous operation . At K band frequencies, where GaN transistors operate at the limits of solid-state technology to achieve high output power, liquid cooling is not an optional upgrade — it is the engineering solution that makes sustained 500W operation at 22–23 GHz viable for ground station infrastructure.
From Artemis to Commercial Lunar Services
NASA’s Near Space Network is being upgraded with K band uplink capability across multiple antennas ahead of the Artemis III mission — the first crewed lunar surface landing — with new 11-metre tri-band antennas providing K band data services at geographically distributed ground sites. Simultaneously, commercial lunar service providers building their own ground networks require the same K band amplification capability, creating parallel demand from both agency and private sector customers.
Ground stations supporting lunar missions operate under fundamentally different constraints than commercial teleport facilities. Contact windows are determined by orbital mechanics, not traffic demand. When a lunar orbiter or surface asset is within range, the ground station must transmit with maximum reliability. There is no opportunity for a re-try during a missed window.
The 22.55–23.15 GHz range is internationally allocated by the ITU for Earth-to-lunar forward link communications. It was selected because it sits adjacent to but avoids the 22.24 GHz atmospheric water vapour absorption peak, making ground-based transmission viable while still benefiting from the narrower beam widths that higher frequencies provide across the Earth-Moon distance. Both NASA and ESA have standardised on this allocation for cislunar mission planning, establishing it as the global interoperability standard for lunar ground station uplinks.
At 22–23 GHz, achieving 500W of output power from GaN transistors generates significant thermal dissipation in a compact physical volume. Forced-air cooling, which is sufficient for lower-frequency or lower-power amplifiers, cannot remove heat efficiently enough to maintain the junction temperatures required for reliable continuous operation. Liquid cooling transfers heat directly from the amplifier’s critical components through a closed-loop system, enabling 24/7 operation at full rated power — the duty cycle required for lunar ground station infrastructure.
K band (18–26.5 GHz) and Ka band (26.5–40 GHz) are adjacent frequency ranges with different ITU allocations. For Earth-to-lunar uplinks, the internationally coordinated allocation is at 22.55–23.15 GHz — within K band. Ka band allocations (typically 27.5–30 GHz for satellite uplinks) are used for commercial GEO satellite services. While related in frequency range, these are distinct bands with different regulatory allocations, antenna designs, and amplifier requirements. Celestia TTI’s K Band SSPAs are specifically engineered for the 22.55–23.15 GHz lunar communication allocation and should not be substituted with Ka band equipment for this application.
Celestia TTI’s K Band SSPAs operate as the high-power RF output stage in a ground station transmit chain. They are agnostic to the modulation and coding standards applied upstream — including CCSDS (Consultative Committee for Space Data Systems) and ECSS (European Cooperation for Space Standardization) waveforms used in space mission communications. The SSPAs amplify the modulated signal produced by the modem or exciter without altering its information content, ensuring compatibility with any standards-compliant waveform your mission requires.
Required output power depends on the ground antenna aperture, link distance, spacecraft receiver sensitivity, and target data rate. For a large dish antenna (15m or above) targeting a well-equipped lunar orbiter, 250W may provide adequate EIRP. For higher data rates, smaller antennas, or direct-to-surface links where the receiving terminal has limited aperture, 500W or phase-combined higher powers may be required. Celestia TTI’s engineering team can assist with link budget analysis to determine the appropriate configuration for your specific mission scenario.
Yes. Both outdoor and indoor (rack-mount) configurations are available, with standard M&C interfaces (RS-485, USB, Ethernet) compatible with ground station management systems. The liquid cooling loop requires integration with a facility chiller or heat exchanger system, which Celestia TTI’s engineering team can specify for your installation requirements.
Celestia TTI manufactures under ISO 9001:2015 certification for the design, development, production, and integration of telecommunications equipment, and ISO 9100:2018 for the provision and management of technical assistance services in the aerospace and defence sector. These certifications are relevant to institutional procurement processes for space agency ground infrastructure.
