1. Addressing The Challenge

Addressing Challenges of LEO Communication: The Old Way

The difficulties small-satellite operators continuously address during missions are abundant: antenna pointing issues, attitude anomalies, atmospheric-induced  fades, rain, and other types of interference, to name a few.  With these factors driving ever-variable signal-to-noise ratios (SNRs) in the communication channel, LEO systems have traditionally been designed to withstand the worst channel conditions possible.  Systems designed only to withstand the worst SNRs, though they offer robust signal protection, make for painfully low-bandwidth solutions. This limitation is a key reason LEO satellites have yet to achieve their full potential in a variety of applications.

2. Firehose Solution

The Firehose Communications System rises to the occasion by bringing a novel, elegant design to the concept of adaptive radio communication. Powered  by a proprietary algorithm developed during the company founders’ work at Los Alamos National Laboratory, the Firehose intelligently adapts the characteristics of the data downlink based on real-time SNR conditions.

But why does that matter? During a typical satellite ‘pass,’ signal strength will vary by a factor of 200 or more. The Firehose fully exploits this variability. When conditions are at their best, CubeSats using the Firehose send as much as 10 Mbps through the channel. As channel conditions degrade and the signal weakens, the Firehose smartly increases the signal buffer (and vice versa). All the while, it sends the optimal amount of data possible given the current channel characteristics.

3. More Data

More Data, Same Power Budget

The Firehose does not require additional power to the communications components of the satellite as it cranks up or down the data sent through the channel by adapting the downlink bit-rate. That is due to the adaptive algorithm’s place in the ground terminal component of the Firehose. From there, it measures the signal strength  and, using a standard, fixed bit-rate uplink, informs the satellite of the appropriate downlink bit-rate. This continuous hand-shaking occurs as frequently as several times per second but does not require more power to the compact, energy –efficient Firehose components onboard the satellite. So the Firehose will make as many as several thousand adjustments to the downlink bit-rate during a typical LEO CubeSat ‘pass’ – and finally bring the recognized benefits of adaptive radio to LEO communications.

4.Benefits

Adding Up the Benefits

The continuous drive by both companies and governments to obtain higher resolution images or better, more comprehensive scientific experiment results—all at a lower cost and in a faster manner—is part of why the Firehose’s benefits are easy to quantify. In just one 12-minute pass over its ground terminal, a Firehose Communications System achieving an average rate of 1.7 Mbps will transmit more than 1.2 Giga-bits of data to earth. By comparison, today’s conventional solutions may transmit 100 Mega-bits at best.

We recognize, too, that today’s CubeSat operators expect their vehicles to fly longer and deliver more. The data advantage of the Firehose continuously compounds. Over the course of one single year, a satellite that completes 5-7 orbits per day has the ability to transmit as much as 2,200 Giga-bits or more, depending on orbit characteristics. For a more comprehensive estimate of the data rates your satellite will achieve given your mission characteristics, we will be providing a Firehose performance calculator (coming soon).

Continuous handshaking. Signal strength improves as a satellite approaches the vertex of the ‘pass,’ and the Firehose adjusts the bit-rate accordingly, as often as several times per second. Below: Cumulative data from one ‘pass’ as a function of the bit-rate variations above.