Improving the SRW Waveform via a Physical Layer Retrofit

In this paper we show that it is possible to improve performance and provide expanded CONOPS for an existing tactical waveform, namely the soldier radio waveform (SRW), via a physical layer retrofit. We integrated a new proof-of-concept physical layer into existing software defined radio (SDR) hardware and with the existing upper open systems interconnection (OSI) layers of SRW, and then demonstrated improvements with head-to-head field trials. To be specific, the new physical layer offers the following improvements over the baseline physical layer of SRW: (i) broadband throughputs above 6 Mbps, (ii) improved robustness to dynamic airborne and terrestrial multipath channels, and (iii) discontinuous spectra with carrier bandwidth flexibility (enabling operation even where continuous bandwidth is unavailable). The physical layer design is based on TrellisWare´s universal air and ground (UAG) physical layer introduced in [1]. In that work, we discuss how the UAG´s flexibility in terms of bandwidth usage and interface to upper layers could be leveraged to provide a physical layer retrofit to an existing waveforms. This paper covers the effort to target SRW, an effort which concluded in a demonstration of significant performance enhancements to SRW.