Astrapi Corporation Awarded a United States Air Force (USAF) AFVentures Phase II Contract

The United States Air Force Research Lab (AFRL),with support from the United States Space Force HQ, awarded a contract to Astrapi to further develop its advanced “Symbol Waveform Hopping“ signal protection capability.


Astrapi Corporation has been awarded a Phase II SBIR contract from the United States Air Force. This contract was issued with support from the United States Space Force (USSF) Headquarters.

The new contract is based on Astrapi’s advanced signal protection capability, Symbol Waveform Hopping (SWH). Astrapi recently completed the competitive Catalyst Cyber Space program, sponsored by the Air Force Research Lab/Space Vehicles directorate, with admission based upon Space Force and Air Force interest in SWH. This project reflects an extension of the validation Astrapi secured through the Catalyst program.

Astrapi has partnered with Space Micro, Inc to demonstrate application of SWH to Space Micro’s production Software Defined Radios (SDRs) as an enhancement option for future procurement. Space Micro’s SDRs are space qualified and are key elements in both commercial and DoD programs such as SDA’s Tranche 0 Transport Layer.

Prior to the program and previously released publicly, Astrapi announced the issuance of U.S. Patent No. 10,931,403, “Communications Devices, Systems, Software and Methods Employing Symbol Waveform Hopping” on February 23, 2021. This is Astrapi’s fifteenth issued U.S. patent.

Symbol Waveform Hopping (SWH) is a new physical layer signal protection communication technology. It is analogous to frequency hopping (FH), but uniquely SWH is in the time domain and protects the transmission by resolution against the noise floor.

Symbol Waveform Hopping exploits the huge symbol waveform design space that is characteristic of Astrapi’s patented Spiral Modulation technology. Astrapi developed the use of Polynomial Symbol Waveform (PSW) alphabets, in which each short message (“symbol”) corresponds to a particular bandlimited polynomial. By creating many PSW alphabets, SWH enables switching between PSW alphabets in a pseudo-random process known only to the sender and intended receiver.

This technology represents a major derivative advancement of Astrapi’s Spiral Modulation capability. Astrapi continues to make foundational improvements at the core physical layer of the communications stack. SWH has broad application across multiple sectors.

Dr. Jerrold Prothero, Founder and CEO of Astrapi Corporation, stated “We are quite excited to begin work on transitioning Symbol Waveform Hopping into a Space Micro Software Defined Radio enabling a transformative capability for signal protection that meets the U.S. Space Force needs. Symbol Waveform Hopping provides an advanced capability to fully protect a signal without the latency and power overhead of standard encryption. Symbol Waveform Hopping is equivalent to forcing potential signal interceptors to recognize an image that is smaller than their pixel size. No amount of computation can improve resolution. We are delighted to be teaming with Space Micro to transition this unique capability into a deployed space-qualified Software Defined Radio platform.”

David Strobel, Co-Founder and Executive Chair of Space Micro said, “Space Micro is excited to be working with Astrapi to further secure SATCOM transmission. Symbol Waveform Hopping promises to complement our production Ka-Band Software Defined Radio transceiver, as well as our other space radios at UHF-, S- and X-Bands.”

ABOUT Astrapi Corporation
Astrapi is the pioneer of Spiral Modulation, Symbol Waveform Hopping and other capabilities which open unexplored areas for innovation at the core of telecommunications. Currently Astrapi has fifteen US patents issued, with more pending and with corresponding international patent coverage. Based on a generalization of Euler’s formula, the foundational mathematics for telecommunications, Astrapi provides fundamentally new ways to optimize the use of the spectrum, new ways to secure signal transmission, and new ways to measure non-stationary spectrum. By applying this new mathematics to signal modulation, Astrapi is able to improve the trade-off between the four fundamental parameters in telecommunications: bandwidth, signal power, data throughput, and error rate. The resulting efficiency translates into higher spectral performance with more bits available at a lower cost. Derivative technologies support unique capabilities for signal protection and accurate in-the-field measurement of real-world nonstationary spectra. Further information at

Space Micro Inc., based in San Diego, CA, is an engineering-driven supplier of affordable, high-performance, radiation-hardened communications, electro-optics, and digital systems for use in commercial, civil, and military space applications around the world. Space Micro solutions include Telemetry, Tracking and Command (TT&C) transmitters, mission data transmitters, space cameras, star trackers, image processors, Command & Data Handling (C&DH) systems and laser communications systems.

For more information, visit or contact Michael Dowd, Vice President of Business Development at (858) 332-0700, extension 122 or via email at [email protected]

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