A low cost, transparent, high gain electro-optic amplifier for fibre access networks

Passive optical network (PON) system architectures are an excellent solution to fibre access but are limited in range and fan-out by the optical power budget especially as the bit rate increases. More flexible architectures can be achieved by inserting optical gain but most solutions propose the use of erbium doped fibre amplifiers (EDFA) which are expensive and have high power consumption in this cost sensitive part of the network. An electro-optic amplifier is presented which has many advantages over EDFAs including low cost, low power consumption and low noise. This amplifier has been implemented using commercial low cost components and provides variable gain with excellent linearity over a wide dynamic range. Its low power consumption and self-contained control systems combine with compact packaging in standard splice management trays to make this technology ideal for deployment in outside plant. System results are presented showing a large increase in power budget for a PON whilst maintaining correct operation of marshalling and ranging functions allowing range extension or increased split ratio. This advance opens up opportunities for more flexible network solutions in the important fibre access market.