Length of Optical Fiber Influence on the Performance of Radio-over-fiber Systems

Abstract

The paper investigates performance impairments due to constraints imposed by the MAC layer when optical fiber is used to extend the IEEE 802.11n network. It is shown that data throughput decreases as fiber length increases. In UDP packet transmission the maximum throughput decreases gradually by 16.6% and 18.6% for basic access and RTS/CTS, respectively. But, with considering TCP packet transmission, the reductions are 21.3% and 22% when the fiber delay increases from 0 to 22.5 μs with using basic mechanism and 0 to 18 μs with RTS/CTS one (i.e., fiber length increases from 0 to 4.3 km and 0 to 3.5 km for basic access and RTS/CTS respectively). It is also noted that the network fails long before physical layer limitations set in due to the timeout values defined within the MAC protocol.