1550 nm band 20 GHz Dual Drive Intensity Modulator The MZDD-LN-20 is a dual drive intensity modulator designed for optical communications at data rates up to 28 Gb/s and analog applications up to 20 GHz. The dual drive design of this Mach-Zehnder modulator confers it a unique combination of very low Vπ, high bandwidth and low insertion loss, and makes it the intensity modulator of choice for a variety of state of the art applications.