Investigation of practical antennas for astronaut body area network

Various antennas have been researched for use in typical wireless body area networks. However, for body area networks deployed inside a spacesuit, the propagation environment has different factors affecting the choice of antennas. In this paper, the impact of employing practical antennas in astronaut body area network is investigated using two common types of antennas: helical monopole and microstrip patch antenna. With these antennas, the path loss of radio channel is studied inside a section of spacesuit at three common frequencies: 433 MHz, 2.4 GHz, and 5.2 GHz. Our main findings are that the channel loss can be reduced by using vertically polarized antennas as opposed to horizontally polarized patch antenna by approximately 2.3 dB per 15 cm for 433 MHz radio channel. However, patch antennas are more desirable as they are conformal to the body and less intrusive. In either case, using both simulations and actual measurements, we show that the path loss is significantly reduced in spacesuit body area networks compared to that in typical civilian body area networks, especially at lower frequencies.