The radiation characteristics of the IDG-TSA and the bowtie slot antenna have been established. The efficacy of a new analytical method for the IDG-TSA has been demonstrated. A novel IDG-TSA feed structure has been proposed which gives performance close to that of rectangular waveguide but which allows greater exploitation of the broadband properties of the antenna, and easier integration with planar circuitry. The operation of both antennas with wideband pulsed excitation has been investigated for the first time. Both structures perform well, with particular promise being shown by the IDG-TSA.