Waveform optimizations for ultrawideband radio systems

Solutions are presented for various optimizations of transient waveforms and signals used in ultrawideband radio systems. These include the transmit antenna generator waveform required to maximize receive antenna voltage amplitude (with bounded input energy), the transmit antenna generator waveform that provides the "sharpest" received antenna voltage waveform, and the transmit antenna generator waveform that maximizes received energy with an inequality constraint on the radiated power spectral density. Using variational methods, general optimization results are derived for arbitrary antennas, including the effects of generator and load impedances, and numerical examples are provided for lossless dipoles and resistively loaded dipoles using moment method solutions. Closed-form results are provided for short dipole antennas for some special cases.