基于OFDM索引调制的通信定位方法

摘要：针对全球导航卫星系统（GNSS）拒止环境下传统定位方法抗干扰能力弱、频谱利用率低及峰均功率比高等问题，提出一种融合惯导与正交频分复用（OFDM）网格编码索引调制的通信定位方案。该方法通过将激活子载波位置作为索引传递基站坐标等导航辅助信息，结合网格编码规则实现导航辅助信息的高效嵌入与解码，同时保留部分子载波用于测距。接收端融合惯性测量单元（IMU）推算与多基站测距结果，采用扩展卡尔曼滤波实现协同定位。仿真结果表明，在多径衰落信道下，所提方案在保障通信性能的同时，定位精度显著优于传统方法，尤其在低信噪比区域具有更强的鲁棒性。

关键词：通信定位一体化；惯性导航；融合定位；索引调制

Abstract: To address the weaknesses of traditional positioning methods in global navigation satellite system (GNSS)-denied environments, including poor anti-jamming capability, low spectrum efficiency, and high peak-to-average power ratio, this paper proposes a communication-positioning solution integrating inertial navigation with orthogonal frequency division multiplexing (OFDM) grid-coded index modulation. By using activated subcarrier positions as indices to transmit navigation-aided information such as base station coordinates, combined with grid-coding rules, this method achieves efficient embedding and decoding of navigation data while reserving some subcarriers for ranging. The receiver integrates inertial measurement unit (IMU)-derived estimates with multi-base station ranging results, employing extended Kalman filtering for cooperative positioning. Simulation results demonstrate that under multipath fading channels, the proposed scheme significantly outperforms conventional methods in positioning accuracy while maintaining communication performance, exhibiting enhanced robustness particularly in low signal-to-noise ratio regions.

Keywords: integrated communication and positioning; inertial navigation; fusion positioning; index modulation