Comparison of jamming robustness of airborne networking waveforms

Abstract

Many future airborne networks will be built around the software-defined joint tactical radio system (JTRS). Because of the programmability of JTRS, planners of these networks will have a great deal of flexibility in their selection of waveforms. There can be a wide variation in the properties of the candidate waveforms, such as data rate, spectral efficiency, latency, and protection against jamming. In order to choose those waveforms which best meet mission needs, these capabilities must be understood. Because of the nodes' high altitudes and use of omnidirectional antennas, airborne networks can be particularly susceptible to jamming. In this paper, we investigate the performance of three representative waveforms in the presence of hostile jamming. One waveform is based on orthogonal frequency division multiplexing (OFDM), a multicarrier modulation technique. The second uses single-carrier direct-sequence spread-spectrum modulation. Finally, a waveform based on the legacy Link 16 system, which uses a combination of frequency-hop and direct-sequence spread spectrum, is considered. Quantitative results comparing the performance of these waveforms against several jamming threats, including tone, partial-band, and frequency-follower jamming, are presented, and techniques to improve their robustness to the interference are considered.