The US Air Force is working on plans to improve HF radio propagation by releasing ionised gas in the upper atmosphere using a fleet of micro satellites
As well as increasing the range of radio signals, the USAF says it wants to smooth out the effects of solar winds, which can knock out GPS, and also investigate the possibility of blocking communication from enemy satellites.
There are at least two major challenges. One is building a plasma generator small enough to fit on a CubeSat – roughly 10 centimetres cubed. Then there’s the problem of controlling exactly how the plasma will disperse once it is released.