This invention relates to a radiating element 20 for use in array antennas. The radiating element 20 is of simplified design and comprises a front region 26 and a rearward region 28 that are preferably substantially rectangular, which permit higher frequency limits than more conventional Vivaldi elements while maintaining the lower frequency limit. Additionally, by deployment of an array of a plurality of such elements 20 such that no gaps are formed between adjacent elements 20 along the array antenna, very wide bandwidth can be obtained using the array.