全帧OFDM-ISAC：联合星座、导频和接收滤波器设计

中文摘要 AI 辅助

正交频分复用（OFDM）集成感知与通信（ISAC）将整个时频帧（包括导频和数据负载）重新用于雷达感知。然而，随机数据负载降低了感知动态范围，并恶化了目标检测和参数估计性能。现有研究通常孤立地优化调制星座、导频模式、功率分配和接收滤波器，忽略了它们对感知模糊结构的耦合影响。为解决这一空白，我们提出了一种针对全帧OFDM-ISAC系统的星座、导频位置与功率分配以及失配接收滤波器的联合设计，该设计在通信速率约束下最小化声明的感兴趣区域（ROIs）内的残余干扰。对于给定的发射信号方案，接收滤波器具有闭式解。在此滤波器下，我们推导了接收器特定干扰底和噪声增强在二维距离-多普勒域上的闭式表达式，表明该底由全帧信号的一个单一有效统计量控制。这一规律将联合设计简化为两步。平衡交错导频放置消除了导频功率提升的确定性栅瓣，然后在信道估计误差下，在速率约束边界上联合选择成形星座和功率分配，该设计在声明的ROI尺寸上达到一阶最优。在服务质量（QoS）约束为传统16-QAM帧速率的98%的情况下，与传统的接收滤波器感知设计相比，所提出的设计显著降低了干扰底，提高了目标检测概率，并实现了更好的测距精度。

英文摘要

Orthogonal frequency-division multiplexing (OFDM) integrated sensing and communication (ISAC) reuses the entire time-frequency frame, including pilots and data payloads, for radar sensing. The random data payload, however, reduces the sensing dynamic range and degrades the target detection and parameter estimation performance. Existing studies typically optimize the modulation constellation, the pilot pattern, the power allocation, and the receive filter in isolation, overlooking their coupled effects on the sensing ambiguity structure. To address this gap, we propose a joint design of the constellation, the pilot placement and power split, and the mismatched receive filter for full-frame OFDM-ISAC systems, which minimizes the residual interference inside declared regions of interest (ROIs) under a communication rate constraint. For a given transmit signaling scheme, the receive filter admits a closed-form solution. With this filter in place, we derive closed-form expressions for the receiver-specific interference floor and noise enhancement over the 2-D range-Doppler domain, which show that the floor is governed by a single effective statistic of the full-frame signaling. This law reduces the joint design to two steps. A balanced staggered pilot placement removes the deterministic grating lobes of pilot-power boosting, and the shaped constellation and the power split are then selected jointly on the boundary of the rate constraint under the channel estimation error, which attains the joint optimum over the constructed shaping levels to first order in the declared ROI size. Under a quality-of-service (QoS) constraint of $98\%$ of the rate of a conventional 16-QAM frame, the proposed design significantly lowers the interference floor, improves the target detection probability, and achieves better ranging accuracy compared to the conventional receive filter-aware design.

发表机构

• Ulsan National Institute of Science and Technology (UNIST)（蔚山科学技术院）
• University of Manchester（曼彻斯特大学）
• National Mobile Communications Research Laboratory, School of Information Science and Engineering, Southeast University（东南大学信息科学与工程学院国家移动通信实验室）
• University College London（伦敦大学学院）

机构由 AI 辅助整理，请以论文原文为准。

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备注

13 pages, 9 figures