We investigate novel pilot-aided transmission of high-order quadrature amplitude modulation (QAM) modulation formats for optical packet-switched networks. The proposed modulation scheme employs a pilot tone operating at the baud rate for noncoherent reception that is highly immune to laser phase noise. The results show that the system performance equivalent to static operation is achieved 5 ns after wavelength switching of a sampled grating distributed Bragg reflector (SG-DBR) tunable laser. © 2009-2012 OSA.