Militarized Direct RF Conversion Software Defined Radio (SDR)

TECHNOLOGY AREA(S): Info Systems
OBJECTIVE: Design and develop a direct RF conversion Software Defined Radio (SDR), using COTS products to the greatest extent possible, which is ruggedized, radiation hardened and Electro Magnetic Pulse (EMP) resistant.
DESCRIPTION: To effectively direct and maintain adequate command and control (C2) of conventional and nuclear forces, communication is critical. Technology is providing adversaries the ability to rapidly deploy and evolve threats that can challenge the communication effectiveness of combatant commands. Further complications are introduced if one must operate through and after a nuclear disturbed environment, due to the distortions introduced into the propagation medium. SDRs show potential to allow for the rapid mitigation and adaptation to threats and environmental distortions. Direct RF Conversion SDRs digitize an entire spectrum of interest versus an analog RF down converted signal. In classical SDR designs an Intermediate Frequency (IF) is digitized from the analog front end of the radio.

This allows for the capability to digitize the spectrum at the antenna and utilize Digital Signal Processing (DSP) techniques to be applied upon the whole spectrum. Sampling normally occurs at the antenna directly after the first bandpass filter sections. It is envisioned that these direct sampled SDRs augment or replace existing systems and may result in reduced SWAP burdens on their respective platforms. This project seeks to develop a militarized version of direct RF conversion SDR, utilizing open source methods, that can function in challenging and pre-, trans- and post- nuclear event disturbed environments.
PHASE I: Through rigorous analysis, modeling and simulation determine feasibility, technical performance, design and cost of proposed solution of Militarized Direct RF Conversion SDRs. Identify performance risks and recommend mitigation strategies to address them.
PHASE II: Utilizing open source architecture, design SDR and develop appropriate RF sampling, direct conversion and DSP algorithms to demonstrate modulation/demodulation and encoding/decoding of modern military communications waveforms in an appropriate frequency band that may be utilized in challenging environment.
PHASE III: Commercial Application: Techniques developed are directly applicable to the cell phone industry and would greatly enhance their performance of their systems. Smaller cell phone tower footprints may result with a correspondingly reduced SWAP and protection from EMP and interference.

Military Application: Though the immediate need is in the Post Nuclear Attack Command Control area of military communications this solution would greatly enhance all military communications architectures.
REFERENCES: 1: http://www.ti.com/lit/wp/slyy068/slyy06pdf2: www.analog.com/media/en/technical-documentation/technical-articles/3276639821628802619Single_Chip_Realizes_Conversion_Rx.pdfKEYWORDS: Software Defined Radio (SDR), Radio Frequency (RF), High-altitude Electromagnetic Pulse (HEMP), Analog To Digital Converter (ADC), Digital To Analog Convertor (DAC), Digital Signal Processing (DSP)
CONTACT(S):
Paul Gilgallon
(315) 330-7111
paul.gilgallon@us.af.mil