Date of Award
Open Access Dissertation
Doctor of Philosophy in Electrical Engineering (PhD)
Administrative Home Department
Department of Electrical and Computer Engineering
Christopher T. Middlebrook
Committee Member 1
Paul L. Bergstrom
Committee Member 2
Committee Member 3
Modulators within Microwave photonic links (MPLs) encode Radio Frequency (RF) signal information to the optical domain for transmission in applications such as wireless access networks and antenna remoting exploiting advantages optical fiber offers over RF coaxial cables including bandwidth, loss, size, weight, and immunity to electromagnetic interference. A critical figure-of-merit in MPLs is spur-free-dynamic-range (SFDR) defining the range of RF signal power a MPL transmits without distortion. Current Mach-Zehnder Interference (MZI) modulators used in MPLs limit the SFDR because of the associated nonlinear sinusoidal transfer function.
A rigorous theoretical method is developed followed by design, fabrication, and testing to investigate a linear ring resonator modulator (RRM) modulator for MPLs. The linear nature of the Lorentzian transfer function for the RRM is utilized over the sinusoidal transfer function within MZI modulators offering significant improvement in MPL SFDR. A novel bias voltage adjustment method is developed for practical implementations improving SFDR of 6 dB versus MZI at 500 MHz noise bandwidth. RRM is shown to be applicable for applications requiring high operational frequencies while in a limited operational bandwidth such as millimeter-wave wireless networks. To improve RRM SFDR in wide operational bandwidths a novel dual ring resonator modulator (DRRM) design is demonstrated. DRRM suppresses the third order intermodulation distortion in a frequency independent process removing SFDR limits of RRM.
Hosseinzadeh, Arash, "LINEAR RING RESONATOR MODULATOR FOR MICROWAVE PHOTONIC LINKS", Open Access Dissertation, Michigan Technological University, 2018.