Modulator Mach Zehnder
Mach Zehnder modulator is one of the integrated optical devices and can support a fiber optic network to be more reliable. Mach-Zehnder modulator is an external optical modulator that uses electro-optical effects that conventionally use modulating signals in the form of digital signals (NRZ, RZ, etc.). The device has a large bandwidth capacity. The device has a modulation speed up to giga order. The advantage of the Mach Zehnder modulator is that it utilizes superposition so that the output signal power becomes larger and allows remote communication with a small BER level.
Mach Zehnder Modulator Function
Mach Zehnder modulator is an electro-optical device used to modulate wave amplitude. As the name implies the modulator is a function of laying out information signals in the form of pulses of light into the carrier signal (carrier) so that it can be transmitted to the destination.
How to Work Mach Zehnder Modulator
A Mach Zehnder modulator consists of two Y-branches placed opposite and separated by distance. Arm both spaced and controlled by external voltage. The first Y branch functions to propagate the incoming light wave, then manipulated by the arm spacing, and out of the Y branch combines the light of the two arms. Mach Zehnder modulator is an external modulator where the information signal and carrier signal are outside the device then the modulation process is on a separate device. When the light is recombined again, the two waves are interfering with each other. If two waves are in phase then a constructive disturbance occurs and the output is ON. If it comes out of phase, destructive interference will occur and the wave will cancel each other, then the output is OFF. For the ON light is represented by 1 binary and to OFF the light is represented by binary 0.
Mach Zehnder Modulator Performance Parameters
According to the nature of the material used, the modulator is divided into two groups: absorbent modulator and bias modulator. In the absorption modulator the material absorption coefficient changes, in the modulator the bias of the material refractive index changes. The absorption coefficient of the material in the modulator can be manipulated by the Franz-Keldysh effect, the Stark Quantum-limited effect, excitonic absorption, changes in the Fermi level, or changes in the free carrier concentration. Usually, if some effects appear together, the modulator is called the electro-absorptive modulator. The bias modulator most often utilizes the electro-optical effect. Some modulators utilize the accousto-optic effect or magneto-optical effect or take advantage of changes in polarization in liquid crystals.
GROUP 15
Phaksi Ghagono Awang Murti (1101154124)
I Gede Aditya Pratama (1101154215)
Wildan Maulani (1101154358)
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