Fiber Optics in Communications and Computing

Peter Persans

Physics Dept., SC1C10, persap

Trans-Atlantic Communications - 1866

10 words/min

Trans-Atlantic Communications: 1998

1013 words/min

A prototypical fiber system

Elements of a communications system

• signal source• transceiver (light source + modulator)• multiplexer• optical fiber• amplifier• optical fiber• demultiplexer• transceiver (receiver)• electronics

Limits of the capability of fibers

• mode dispersion• material dispersion• waveguide dispersion

Fundamental limits of fibers: attentuation

Fundamental Limits

• Limit on the amount of power we can put into one end of a fiber (non-linear loss)

• Limits on the separation of two digital bits from one another (dispersion)

• Limits on the loss in a fiber with distance• Limits on the detection of a signal from a background.

Fundamental limits