An international team of astronomers report the discovery of a long-period radio transient, which is unusually circularly polarized and showcases an accelerating spin period. The finding of the new ...

High-frequency (HF) ground wave radar is widely used in maritime target detection and marine environment observation. Its performance is often degraded by co-frequency interference of the HF band. It ...

Ray techniques are used to construct an approximate solution for radio waves propagating in the ionosphere when the loss of energy due to collisions is not negligible. For the time-harmonic problem, ...