| 摘要 |
An optical transmitter uses first 107 and second 108 digital signal processors (DSP) to pre-emphasise first and second electrical digital streams respectively. The pre-emphasised first and second digital streams undergo digital to analogue conversion 109 and the resulting signals are used to modulate 104, 105 the outputs of first and second optical emitters 102, 103 respectively. The outputs from the first and second optical emitters have different wavelengths or polarisations. The two modulated signals are input to an interleaver 108 which outputs a single stream. The digital pre-emphasis compensates for the wavelength-dependent power transfer function of the interleaver. The transmitter output contains multiple wavelength components; in the prior art this referred to as a wavelength division multiplexed (WDM) output signal. A complementary coherent receiver is also disclosed which performs electronic post-equalisation to compensate for an interleaver in the receiver. The interleavers may be Mach-Zehnder interleavers (MZI). |
