论文标题
在Tukey信号下直接检测的实际考虑因素
Practical Considerations in Direct Detection Under Tukey Signalling
论文作者
论文摘要
与直接检测相比，与直接检测（IMDD）相比，Tukey信号传导中有意引入受控的隔膜干扰（ISI）可以使信号振幅恢复，并在直接检测中恢复信号相。使用集成和降低检测器的使用使精确的波形整形不必要，从而使该方案具有高度的鲁棒性，以使实用调节器引入的非线性信号扭曲。从星正正化振幅调制（SQAM）格式绘制的信号序列承认有效的格式描述，该描述促进了在射击噪声和热噪声的情况下，在最大可能的序列检测中促进了代码书的设计和低复杂性。 Under the practical (though suboptimal) allocation of a 50% duty cycle between ISI-free and ISI-present signalling segments, at a symbol rate of 50 Gbaud and a launch power of -10 dBm the Tukey scheme has a maximum theoretically achievable throughput of 200 Gb/s with an (8,4)-SQAM constellation, while an IMDD scheme achieves about 145 Gb/s using PAM-8.请注意，提到的两个星座具有相同数量的幅度水平，吞吐量的差异是由于使用复杂值的信号星座在利用相位信息而产生的。
The deliberate introduction of controlled intersymbol interference (ISI) in Tukey signalling enables the recovery of signal amplitude and (in part) signal phase under direct detection, giving rise to significant data rate improvements compared to intensity modulation with direct detection (IMDD). The use of an integrate-and-dump detector makes precise waveform shaping unnecessary, thereby equipping the scheme with a high degree of robustness to nonlinear signal distortions introduced by practical modulators. Signal sequences drawn from star quadrature amplitude modulation (SQAM) formats admit an efficient trellis description that facilitates codebook design and low-complexity near maximum-likelihood sequence detection in the presence of both shot noise and thermal noise. Under the practical (though suboptimal) allocation of a 50% duty cycle between ISI-free and ISI-present signalling segments, at a symbol rate of 50 Gbaud and a launch power of -10 dBm the Tukey scheme has a maximum theoretically achievable throughput of 200 Gb/s with an (8,4)-SQAM constellation, while an IMDD scheme achieves about 145 Gb/s using PAM-8. Note that the two mentioned constellations have the same number of magnitude levels and the difference in throughput is resulting from exploiting phase information under using a complex-valued signal constellation.
