At the other end of the PS-FBG, an optical sideband is ob-
tained which is sent to the PBC with part of the light wave from
the TLS. The two light waves are orthogonally polarized at the
output of the PBC, and are sent to a 40-GHz PolM (Versawave).
The PC between the PBC and the PolM is used to ensure that the
polarization directions of the two orthogonally polarized light
waves are aligned with the principal axes of the PolM.
Fig. 3 shows the two orthogonally polarized light waves at the
output of the PBC. The wavelength spacing between the optical
carrier and the sideband is controlled to generate a microwave
signal with a frequency at 10 GHz or a 15 GHz. From Fig. 3
we can clearly see that the wavelength of the sideband is not
changed, at about 1549.27 nm, while the optical carrier from the
TLS is increased from 1549.35 nm to 1549.39 nm, correspond-
ing to an increase in the frequency of the generated microwave
of 5 GHz.
The PolM is driven by a phase-coding or frequency-chirping
signal generated by an arbitrary waveform generator (AWG,
Tektronix, AWG7102). At the output of the PolM, two comple-
mentary phase-coded or frequency-chirped optical light waves