Application of Semiconductor Optical Amplifiers in Scalable Switched Radio-over-Fiber Networks

This paper reports the use of semiconductor optical amplifier (SOA) based routing switches in radio-over-fiber (RoF) systems. It is shown that only little additional penalty is introduced by the switches. A proof-of-principle 10 × 10 switching unit is employed in a time-domain switched RoF network, where an SFDR of 96.5dB·Hz
^2/3
is achieved and a 10MSymbol/s QPSK modulated signal at a carrier frequency of 2.5GHz is switched with an EVM of 1.48%. Switching times as low as 50μs are achieved, limited by the driving circuitry of the SOAs. Furthermore, it is demonstrated that the switch is scalable and can be cascaded.