  Modern optical systems send and receive ultra-short temporal pulses (USP).
While ultra-broad band antennas do exist in the microwave region (e.g.,
log-periodic antennas, or, concentric loop antennas), their short temporal
response is typically limited by the antenna's large dispersion, hence,
resulting in a substantial pulse broadening. Here we show that loop antennas
may exhibit USP attributes, below 400 ps (or, an equivalent coherent band pass
exceeding 2.5 GHz) with only three loops, or, with a single, thick loop.
