A new approach to estimate the direction-of-arrival (DOA) in a Time-Modulated Array (TMA) system with a bipolar squared periodic time-modulating sequence is proposed in this letter. Using such a sequence can increase the power of harmonic components of the received signal. Based on this fact, we formulated a new parameter pertaining to the ratio of the upper and lower sideband first harmonic components of the received signal, to improve the accuracy of the DOA estimation in a low signal-to-noise ratio (SNR) environment. A numerical analysis was performed to verify the effectiveness of the proposed DOA estimation method.

中文翻译：

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双极平方周期序列控制的时间调制阵列系统到达方向估计


本文提出了一种在具有双极平方周期性时间调制序列的时间调制阵列（TMA）系统中估计到达方向（DOA）的新方法。使用这样的序列可以增加接收信号的谐波分量的功率。基于此，我们制定了一个与接收信号的上下边带一次谐波分量之比相关的新参数，以提高低信噪比（SNR）环境下DOA估计的准确性。进行数值分析以验证所提出的 DOA 估计方法的有效性。