In this letter, we develop a general iterative receiver based on the minimum mean squared error with parallel interference cancellation (MMSE-PIC) for cyclic prefix (CP)-free transmission. In particular, we consider that the receiver detects several blocks jointly, which allows backward block correction (BC). Additionally, we provide a structure with reduced complexity for Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Chirp Division Multiplexing (OCDM) waveforms. As expected, the results show that our BC-based receiver improves the performance compared with a receiver without BC. Moreover, we show that OCDM outperforms OFDM, and has practically no performance loss compared to CP-OFDM, which motivates the use of OCDM instead of CP-OFDM to decrease latency and increase spectral efficiency.

中文翻译：

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一种用于选频信道下无CP传输的新型迭代接收器设计

在这封信中，我们开发了一种基于最小均方误差和并行干扰消除 (MMSE-PIC) 的通用迭代接收器，用于无循环前缀 (CP) 传输。特别地，我们考虑接收器联合检测多个块，这允许反向块校正（BC）。此外，我们为正交频分复用 (OFDM) 和正交啁啾分复用 (OCDM) 波形提供了一种降低复杂性的结构。正如预期的那样，结果表明我们基于 BC 的接收器与没有 BC 的接收器相比提高了性能。此外，我们表明 OCDM 优于 OFDM，并且与 CP-OFDM 相比几乎没有性能损失，这促使使用 OCDM 代替 CP-OFDM 来减少延迟并提高频谱效率。