Abstract :
Soldier, police, firefighter, forest worker, etc. in the field need "hands free" operation for their wireless equipment. A solution is to use antennas borne or worn on their helmet (as helmet antenna) or on their upper torso (as vest antenna). The design of body-wearable antennas has become increasingly more challenging as its frequency bandwidth escalates. Furthermore, the larger the bandwidth required, the more difficult it is to meet regulatory mandate of radiation safety and user mandates for body-wearability, light-weight, cost, etc.However, major wireless systems on the drawing board, such as UWB (ultra-wideband), dynamic spectrum, software radio, JTRS (joint tactical radio system), multifunction automobile antennas, etc. are demanding ever-increasing bandwidths. This paper presents some recent efforts in broadbanding and size reduction for helmet and vest antennas motivated by market needs.