I wish to suppress the carrier wave from the phase modulated output of an Electrooptic phase modulator and use only the sidebands.
You can suppress the carrier by using modulations such as CSRZ DPSK ( Carrier suppressed Return to zero- Differential phase shift keying) scheme. These may require two or three MZM,s.
if you adjust the bias voltage you can. What software are you using?
I am using Matlab to model the phase modulator. How should I determine the value of the bias voltage that will suppress the carrier?
please go through some books like Analog optical links, Microwave Photonics and find the suitable mathematical model which includes the bias voltage.
If you are modelling the optical waveform in Matlab, then calculate the mean in-phase and quadrature components of the field. Adjust the drive to the phase modulator to minimise the sum of the squares of the mean I and Q fields.
The carrier amplitude depends principally on the phase amplitude and the modulation waveform. Bias voltage is relevant only as far as it effects the linearity and gain of the modulator.
For BPSK modulation using a pure phase modulator, a peak-to peak phase excursion of (for example) 200 degrees may be needed to balance the negative quadrature component of the '1' and '0' phases against the quadrature field introduced during transitions between the two states. In contrast, with an ideal square wave modulation, the transition time is negligible, and 180 degrees peak to peak phase modulation is appropriate - assuming equal numbers of "zero" and "one" symbols.
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