Small Wideband Antenna with non-Foster Loading Elements

The paper demonstrates a new way of overcoming the fundamental limit imposed on the fractional bandwidth of small antennas in relation to antenna volume by means of using a non-Foster (active) network. Unlike the techniques known in literature that use non-Foster matching circuits to broaden the operating bandwidth of electrically small antennas, the present approach utilizes the specific antenna structure with an additional port which is loaded by a non-Foster reactive element. The combination of properties of the specific two port antenna structures and the reactive loads produces an extremely wideband response not achievable with passive antennas of the same volume.