This segmentation creates a network with many dedicated return links. Finding an efficient and cost-effective architecture to transmit the information on the multitude of return links presents a challenge. Several technologies exist that may be applied to create many possible network architectures. In part one of this two-part series, we will explore four technologies used to create network architectures. Multiple fibres The simplest technology for transmitting multiple returns is to dedicate a separate return transmitter, return receiver and fibre for each.
FP lasers are less expensive and have the poorest performance.
In addition, they have significant operational limitations, such as poor thermal stability. The noise level of these lasers, in particular, will vary greatly with temperature. At certain temperatures the noise level will be quite good even better than that of a typical uncooled DFB laser. A return system must be designed accounting for the worst-case performance over the full operating temperature range or the network will not perform properly under all conditions. This increase may become a significant source of noise if multiple return links are combined and only a single return laser is modulated at any given time.