Many implementations of optical finite impulse response filter for signal processing applications have been realized in integrated photonics using 2 × 2 couplers. We have implemented a filter using 4 × 4 couplers. Such a filter is useful for the compensation of residual dispersion in a fiber optic transmission system. Silicon photonics realization using 4-port multimode interference couplers in 4 $\mu$m silicon-on-insulator technology has been carried out for a free spectral range of 100 GHz. The transmission and group delay for the fabricated device have been measured and a good agreement between the simulation and experimental results has been achieved. The proposed filter can compensate up to ±176 ps/nm of fiber chromatic dispersion.
© 2012 IEEE
Abdul Rahim, Stefan Schwarz, Juergen Bruns, Karsten Voigt, Dimitar Ivanov Kroushkov, Mohammed Tareq Arnous, Christian G. Schäffer, and Klaus Petermann, "Finite Impulse Response Filter Using 4-Port MMI Couplers for Residual Dispersion Compensation," J. Lightwave Technol. 30, 990-996 (2012)