论文标题
信封对非正交多访问有益吗？
Is the Envelope Beneficial to Non-Orthogonal Multiple Access?
论文作者
论文摘要
非正交多访问（NOMA）能够在同一时间频率资源元素中为不同数量的用户提供服务，并且可以利用此功能来携带其他信息。在正交频施加多路复用（OFDM）系统中，我们提出了一种新型增强的NOMA方案，称为NOMA具有信息包膜（Noma-EI），以探索Noma信号包膜的灵活性。在此方案中，除经典信号星座外，量化的信号包络还传达了数据位。不同用户的子载波激活模式由信封前共同决定。在接收器中，采用连续的干扰取消（SIC），我们还引入了信封检测系数以消除误差地面。 Noma-IE提供了光谱效率和能效的理论表达。然后，考虑到二进制相移键调制，我们得出了DM子块的两次提取器的渐近位错误率。之后，将表达式扩展到四核算机案例。分析结果表明，不完美的SIC和索引误差是降低误差性能的主要因素。数值结果表明，Noma-IE优于OFDM和OFDM-NOMA，尤其是在高信噪比（SNR）方面。
Non-orthogonal multiple access (NOMA) is capable of serving different numbers of users in the same time-frequency resource element, and this feature can be leveraged to carry additional information. In the orthogonal frequency division multiplexing (OFDM) system, we propose a novel enhanced NOMA scheme, called NOMA with informative envelope (NOMA-IE), to explore the flexibility of the envelope of NOMA signals. In this scheme, data bits are conveyed by the quantified signal envelope in addition to classic signal constellations. The subcarrier activation patterns of different users are jointly decided by the envelope former. At the receiver, successive interference cancellation (SIC) is employed, and we also introduce the envelope detection coefficient to eliminate the error floor. Theoretical expressions of spectral efficiency and energy efficiency are provided for the NOMA-IE. Then, considering the binary phase shift keying modulation, we derive the asymptotic bit error rate for the two-subcarrier OFDM subblock. Afterwards, the expressions are extended to the four-subcarrier case. The analytical results reveal that the imperfect SIC and the index error are the main factors degrading the error performance. The numerical results demonstrate the superiority of the NOMA-IE over the OFDM and OFDM-NOMA, especially in the high signal-to-noise ratio (SNR) regime.
