Abstract Optical label switching (OLS) is regarded as one promising solution for the packet-based optical switching. In this paper, a novel modulation, i.e., Manchester code + NRZ modulation is proposed for OLS. The Manchester coded payload signal the NRZ label signal are combined and then modulated onto an optical carrier by only one ASK modulator. The Manchester coded payload signal and the NRZ label signal are recovered by half-bit-delayed differential and a low-speed ASK receiver, respectively. Better than traditional orthogonal modulation, the proposed Manchester code + NRZ modulation requires no non-amplitude modulation and only one ASK modulator, reducing the equipment cost, modulation loss and operation complexity. The coding is simple and decoding is not required. According to theoretical analysis and simulation test, the induced crosstalk decreases with the bit rate ratio. The tested results verify the feasibility of the OLS based on the proposed Manchester code + NRZ modulation.

中文翻译：

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基于曼彻斯特码+NRZ调制的光标签交换

摘要 光标签交换（OLS）被认为是一种很有前途的基于分组的光交换解决方案。在本文中，针对OLS 提出了一种新颖的调制，即曼彻斯特码+NRZ 调制。曼彻斯特编码的有效载荷信号和 NRZ 标签信号被组合，然后仅通过一个 ASK 调制器调制到光载波上。曼彻斯特编码的有效载荷信号和 NRZ 标签信号分别由半位延迟差分和低速 ASK 接收器恢复。曼彻斯特码+NRZ调制比传统的正交调制更好，不需要非幅度调制，只需要一个ASK调制器，降低了设备成本、调制损耗和操作复杂度。编码简单，不需要解码。根据理论分析和仿真试验，引起的串扰随着比特率比的增加而减少。测试结果验证了基于提出的曼彻斯特码 + NRZ 调制的 OLS 的可行性。