High-Speed Data and Pulse Carver Alignment in Dual Mach-Zehnder Modulator Optical Transmitters using Microwave Signal Processing
01 February 2003
A new technique for aligning the pulse carver and data modulator in a dual Mach-Zehnder modulator optical transmitter is presented. This approach relies solely on the photodiode detected microwave power spectrum of the transmitted optical signal. Experimental results are presented that illustrate the spectral property to be exploited and two proposed techniques for designing a low cost automated carver and modulator alignment system. A mathematical explanation for the spectral phenomenon is presented and shown to agree quite well with measurement and simulation results.