An ultrawideband digital signal design with power spectral density constraints

Sets of ultra-wideband signals are designed and generated using a mathematical model of a zero-order hold, digital-to-analog converter. An efficiency measure of filling the FCC spectral mask is developed and optimized for various choices of digital-to-analog converter parameters and waveform time duration. The proposed optimization technique takes into account filtering effects in the digital-to-analog converter as well as a measured antenna transfer function characteristic. The research presented here demonstrates that a simple ultra-wideband transmitter can be designed which consists only of a high speed digital-to-analog converter and a suitable ultra-wideband antenna. The waveform design problem is explicitly dependent on the transmitter's equivalent transfer function, the FCC spectral mask constraint, and the ultra-wideband antenna that is included as a factor in the equivalent transfer function of the system.