Non-line-of-sight ultraviolet (UV) communication technology to support unattended ground sensor communication is described. The concept exploits atmospheric scattering of ultraviolet light to achieve modest data rates under non line-of-sight (ground-to-ground) and obstructed line-of-sight (foliage penetration) conditions. The transmitter consists of a digitally modulated UV source and the receiver employs a sharp cutoff solar-blind absorption filter coupled to a channel photomultiplier module. Prototype semiconductor UV sources with center wavelengths in the solar blind region (<280nm) already offer higher power efficiency than lasers, along with advantages in size, simplicity, and flexibility relative to both lasers and traditional mercury sources. Once commercialized, semiconductor UV sources will also offer significant cost savings over traditional gas-discharge and solid-state UV sources. In this paper, the temporal and spectral properties of a number of prototype semiconductor UV sources are presented and compared to a low-pressure mercury vapor source. Efficient modulation and data coding methods compatible with the output characteristics of both sources are discussed, and measurements from recent test bed experiments are presented.