频率选择性衰落信道中超奈奎斯特信号的受限容量
Constrained Capacity for Faster-than-Nyquist Signaling in Frequency-Selective Fading Channels
- Carleton University（卡尔顿大学）
- Middle East Technical University（中东科技大学）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文研究频率选择性信道下DFT预编码FTN信号的受限容量，通过CP/CS分解干扰并推导失配解码速率，证明FTN优于奈奎斯特传输。
中文摘要 AI 辅助
本文研究了在频率选择性信道上，采用有限字母输入的离散傅里叶变换（DFT）预编码超奈奎斯特（FTN）信号的受限容量。通过引入循环前缀（CP）和循环后缀（CS），FTN和多径引起的符号间干扰（ISI）被分解为并行的特征信道，其特征增益由折叠的FTN频谱和信道频率响应共同决定。基于此分解，我们推导了有限字母星座的受限容量，并为无CP/CS的DFT预编码FTN信号构建了失配解码可达信息速率，量化了因非完美对角化导致的有限块速率损失。我们发现，即使在失配解码下，FTN相比奈奎斯特传输仍有显著提升。
英文摘要
In this paper, we investigate the constrained capacity of discrete Fourier transform (DFT)-precoded faster-than-Nyquist (FTN) signaling over frequency-selective channels with finite-alphabet inputs. With a cyclic prefix (CP) and cyclic suffix (CS), the FTN and multipath induced intersymbol interference (ISI) is decomposed into parallel eigenchannels, whose gains are jointly determined by the folded FTN spectrum and the channel frequency response. Based on this decomposition, we derive the constrained capacity for finite-alphabet constellations and formulate a mismatched decoding achievable information rate for DFT-precoded FTN signaling without CP/CS, quantifying the finite-block rate loss caused by imperfect diagonalization. We find that even under mismatched decoding, FTN significantly improves upon Nyquist transmission.
