In this paper two millimetre-wave (mm-wave) generation techniques involving optical heterodyne detection and the Mach-Zehnder Modulator (MZM) based optical comb technique are investigated. The heterodyne detection system is followed by a second order electrical feedback loop to reduce the phase noise. Simulations are carried out to study the effects of the laser parameters (e.g. RIN, Henry coefficient) on the generated mm-wave signal.
The optical comb is made by a single driven MZM. The optimum biasing point is investigated and two lasers with different characteristics are used successively to generate optical comb. The two mm-wave generation methods are compared based on their carrier to noise ratio (CNR) performance.