Velocity-mismatch compensation in traveling-wave modulators using pseudorandom switched-electrode patterns

Abstract

The modulation impulse response of a traveling-wave modulator with an arbitrary aperiodic switched-electrode pattern is directly derived in the time domain. It is shown that applying the phase reversals according to a suitable pseudorandom sequence considerably increases the bandwidth-to-drive-voltage ratio figure of merit. This improvement is attributed to the spread-spectrum properties of pseudorandom sequences and may be obtained by appropriate choice of such sequences. Examples are given for modulators based on the Barker codes.