Improved UHF capabilities using medium gain antennas

This proposal aims to enhance UHF proximity link capabilities to support the next generation of smaller, low-cost Mars explorers. By offering a UHF link that can dynamically adjust its gain, beam shape, and pointing, the system ensures optimized communication performance for a wide range of mission scenarios. This will be done relying on new Radio capabilities already implemented on the UST-lite which provides multiple outputs with phase and amplitude control.

The primary objective of this proposal is to achieve up to a 10x improvement in direct to orbit communications for very small elements on the surface of Mars. This makes these small assets 10x more cable in science return. This enhancement will enable direct communication with low Size, Weight, and Power (SWAP) assets on the Martian surface, such as helicopters, small rovers, and tubebots, facilitating more efficient data transfer and mission flexibility and vastly extend the area of operation.

The secondary objective is to retain the current UHF capabilities while introducing adaptive telecommunications features. These advanced capabilities will allow for intelligent communication solutions, making the system versatile and suitable for a broad range of future Mars missions.

Utilizing the existing capabilities of the UST-lite radio, the proposed new antenna will offer three operational modes: (1) a traditional low-gain broad beam (to maintain current capabilities), (2) a high-gain beam with electrical steering (±45°), and (3) a isoflux beam. Each mode is controlled via UST output ports, which imposes the phase and amplitude of each element, thereby eliminating the need for a complex power divider and T-R (transmit-Receive) modules. Existing Mars orbiters such as Mars Odyssey, MRO, MAVEN, TGO, are using quadrifilar helix low-gain antennas (LGA) with gain ranging from 0dBic to 3dBic to communicate with Mars rovers and landers. The most recent orbiters are using adaptative data rate (ADR) to achieve data rate ranging from 1 to 2048 kilobits per second (kbps). By incorporating a hemispherical helical antenna, we can increase the element gain by 4 dB compared to the existing orbiter UHF antenna. With the UST-lite radio's capabilities, we plan to array 4 elements to achieve: (1) a low-gain broad beam for traditional communication, (2) beam steering with ±45° angular adjustment and high gain, and (3) isoflux coverage for broader signal distribution. The HGA configuration will provide up to 6dB of additional gain, resulting in a total improvement of 10 dB at boresight.

Consequently, this will allow us to use an output RF power that is 10 times smaller on Martian assets, enabling the use of smaller vehicles while maintaining the same data rate. For example, the MRO Electra Tx Power is 7 W (~ 37.5 dBm) and the MSL Electra Lite Tx Power is 8 W (~ 39.5 dBm). This would allow us to achieve the same data rates with RF output power under 1W which is compatible with smaller platforms like helicopters or small rovers. For reference, the latest low-SWAP radio (ARKE) developed by JPL for small platforms to communicate with orbiters will support 2W RF output power.

This proposal directly addresses three key initiatives of the Mars Exploration Program (MEP):

1. Expand opportunities to explore Mars through competed, lower-cost, more frequent flight opportunities: The proposed UHF array will enable smaller, lighter Mars explorers, such as rovers and helicopters, to communicate directly with orbiters. This capability is crucial for smaller assets that are often part of cost-efficient missions designed to produce impactful science. By optimizing communications infrastructure, we can accommodate a higher frequency of low-cost missions that continue to advance scientific discovery.
2. Strengthen and broaden infrastructure at Mars to enable a diverse set of missions and new opportunities for partnerships: The UHF array significantly enhances Mars communication infrastructure by incorporating beam-steering capabilities and adjustable gain. This flexibility allows orbiters to switch between high-gain for smaller assets and wider coverage low-gain for critical Entry, Descent, and Landing (EDL) events. The ability to steer beams ensures that communication can be dynamically optimized based on mission needs, effectively maintaining the infrastructure and ensuring the longevity of communication systems.

Invest in key technologies to enable expanded access to, and scientific understanding of Mars: The proposed array introduces advanced high-gain, beam-steering technology that enables fully autonomous smaller explorers via direct to orbiter relay comm. This enables small explorers to be placed, or travel to, virtually any location on the surface Mars. In addition, by generating an isoflux radiation pattern, the array increases number of relay passes and average pass duration for larger landed assets. The proposed tunable capability allows for more flexible mission designs and innovative exploration strategies, such as deploying multiple large and small rovers or helicopters on the Martian surface.

Using topology optimization (TO), we will design a lightweight, four-element array with a 70% reduction in mass compared to conventional approaches, ensuring the total array mass is comparable to existing single-element systems. Coupling this lightweight design with higher-efficiency antennas will yield up to a 10x improvement in data volume relative to current capabilities.

This is early/mid-stage (TRL 3) — the most realistic path in is NASA SBIR/STTR, which funds small businesses and research institutions to develop technology aligned with NASA's needs (equity-free, phased funding). Check whether a current SBIR/STTR solicitation topic overlaps with this project's technology area, or contact the project directly (above) to ask.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.