What are some ways to increase the capacity of an optical system?

Following are the few options that can help increase capacity of an Optical System

1.  Increasing the signal’s frequency
2. Increasing the number of fibers
3. Increasing the number of channels
4. Increasing the modulation complexity.

The first option would require a proportional increase in bandwidth, while the other options would require the inclusion or replacement of equipment, resulting in higher cost, complexity, and power consumption.