多项选择题
A. PIN photodiodes B. zero-chirped lasers C. Erbium-doped fiber amplifiers D. dispersion compensating fiber E. dispersion compensating Bragg grating
A. They are both regions of lowest loss. B. They are both regions of low reflections. C. They are both regions of low index of refraction. D. They are both regions of low chromatic dispersion. E. They are both regions of low Polarization Mode Dispersion （PMD）.
A. low optical powe B. high optical power C. few optical channels D. many optical channels E. low chromatic dispersion F. high chromatic dispersion G. too much power differential in the optical channels