by Fairwaves

The first ever truly embedded SDR

View all updates Dec 19, 2019

Field Report: XTRX for Satellite Communication

by Ivan S

Greetings from Moscow. We are the LEO-SDR project team. LEO stands for Low Earth orbit, so we’re simply a team of students in Youth Space Center of Bauman Moscow State Technical University involved in designing cubesats (very small and relatively cheap satellite, consisting of multiple 10x10x11.35 cm3 cubic units).

Our current challenge is developing a high-performance, flexible communication and storage system for cubesat, including a baseband processor combined with SSD storage and an RF front-end module. Specialized satellites with such system as a payload can be used for many different missions: in-situ EMC and propagation research, SDR-on-orbit HAM receiver, "a space router" for a swarm of research or commercial cubesats, or even something like inter-satellite internet (with a large constellation).

The XTRX is the key component of the baseband processor. Its very wide bandwidth and frequency coverage allowed us to simplify the front-end while its embeddability relieved us from the need to develop a custom, application-specific SDR.

The main design idea used in the LEO-SDR core board is to connect XTRX to both a Cortex-A53 and an NVMe SSD via PCIe bus. This solution should enable XTRX’s FPGA to work with the SSD directly, recording even full-bandwidth I/Q streams while bypassing processor. That’s very important to satisfy the severe power constraints of a small satellite since it allows most of the DSP and packet processing work to be done by the FPGA, only using the ARM for some heavy and non-trivial algorithms.

Our next step is to get more familiar with the XTRX FPGA, specifically with how to implement code for optimized PCIe data transfer.

About the Author

Ivan S

 Moscow, Russian Federation

$722,433 raised

of $90,000 goal

802% Funded! Order Below

Product Choices


XTRX Pro Rev 5

XTRX Pro Rev 5 board. Does not include any cables, antennas, or adapter boards.


PCIe x2 Lite Adapter

This PCIe card securely holds an XTRX board (not included) so it can be used in a standard PCIe x4 slot. This adapter achieves the full 10 Gbit/s raw bus bandwidth and can be plugged into x4/x8/x16 PCIe slots. A six-pin JTAG connector makes it easy to program and debug the FPGA. Includes six SMA-to-U.FL cables, two screws for mounting your an XTRX board, and four 8 cm U.FL-to-U.FL cables.


4G/LTE External Antenna

From the Crowd Supply Basics project.

Abracon External Antennas exhibit low return loss characteristics, high gain, and Low Voltage Standing Ratio (VSWR). These external antennas are linearly polarized and come in a low profile package.


U.FL-to-SMA Cable

From the Crowd Supply Basics project.

A Hirose U.FL to SMA (jack) bulkhead straight connector with a 1.32 mm diameter cable. Less than -2 dB cable insertion loss up to 6 GHz. Both connectors are gold-plated brass and the cable conductor is silver-coated copper.


Active GPS Antenna

From the Crowd Supply Basics project.

A low-noise active GPS antenna suited for the GPS L1 band. Accepts 3-5V DC and outputs RF via an SMA(m) connector. Optional adhesive mounting.



We are a vertically integrated vendor of cellular equipment focused on the needs of emerging markets. We are developing, manufacturing, deploying, and operating turn-key cellular network solutions including radio equipment, towers, power and backhaul all the way to a core network and SS7 interconnect. Our team has been building software-defined radios and systems based on them since 2009 and is well known for its ClockTamer, UmTRX, and UmSITE products.

Alexander Chemeris


Sergey Kostanbaev

Software & Firmware Development

Andrey Sviyazov

Hardware Design

Albert Gardiner


Andrey Bakhmat


Andy Avtushenko


See Also

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