  Current state of the art quantum computing experiments in the microwave
regime use control pulses generated by modulating microwave tones with baseband
signals generated by an arbitrary waveform generator (AWG). Recent advances in
digital analog conversion technology have made it possible to directly
synthesize arbitrary microwave pulses with sampling rates up to 92 gigasamples
per second (GS/s). These new high bandwidth AWG's could dramatically simplify
the classical control chain for quantum computing experiments, enabling more
advanced pulse shaping and reducing the number of components that need to be
carefully calibrated. Here we use a high speed AWG to study the viability of
such a simplified scheme. We characterize the AWG and perform randomized
benchmarking of a superconducting qubit, achieving average single qubit gate
error rates below $5\times10^{-4}$.
