We describe an experimental heterodyne lightwave transmission system operating at 4 Gb/s. Our optical sources were 1.5-μm wavelength DFB and DBR semiconductor lasers. ASK, FSK, and DPSK modulation formats were investigated, and baseline receiver sensitivities of 175, 191, and 209 photons/bit, respectively, were achieved. We also report transmission experiments through up to 160 km of conventional singlemode fiber and up to 175 km of dispersion-shifted fiber.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering