The Cramér-Rao bound (CRB) for direction of arrival (DOA) estimation exploiting both auto-correlation and cross-correlation information within multiple frequencies of the received array signals is derived. It provides a tighter bound than the existing CRB for the dual-frequency scenario. For the multiple frequencies, it is much lower than its dual-frequency counterpart, and also exists for a greater number of sources, thereby validating that exploiting multiple frequency pairs can improve both estimation accuracy and target resolvability.

中文翻译：

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利用多频率对进行 DOA 估计的 Cramemer-Rao 界限


利用接收阵列信号的多个频率内的自相关和互相关信息推导出用于到达方向（DOA）估计的克拉梅尔-饶界（CRB）。它为双频场景提供了比现有CRB更严格的限制。对于多频率，它比双频对应物低得多，并且也存在更多数量的源，从而验证利用多频率对可以提高估计精度和目标分辨率。