Phase-modulated continuous-wave (PMCW) radar systems possess inherent interference mitigation capabilities and can be useful for many civilian applications including autonomous driving. For PMCW radar systems, binary sequences with good autocorrelation properties are used as probing sequences due to their low cost to generate in practical hardware systems. However, the non-linearity (NL) suffered by practical PMCW radar systems can produce undesirable cross-products and distort the receiver matched filter outputs. The purpose of this paper is to investigate the properties of the well-known periodic binary almost perfect autocorrelation sequences (APAS) under NL conditions, including even-order and odd-order NL conditions. We also consider designing long binary periodic sequences with low autocorrelation sidelobes within a low correlation zone (LCZ) using a computational algorithm. The computationally optimized sequences (COS) do not suffer from sequence length restrictions and offer much higher diversity than their APAS counterparts. We compare COS with APAS under NL conditions. We show that both types of sequences can be used to avoid ghost peaks in the range profiles under NL conditions.

中文翻译：

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系统非线性存在下周期二元数列的性质

相位调制连续波 (PMCW) 雷达系统具有固有的干扰抑制能力，可用于包括自动驾驶在内的许多民用应用。对于 PMCW 雷达系统，具有良好自相关特性的二进制序列被用作探测序列，因为它们在实际硬件系统中生成成本低。然而，实际 PMCW 雷达系统所遭受的非线性 (NL) 会产生不希望的交叉积，并使接收器匹配滤波器输出失真。本文的目的是研究众所周知的周期性二进制几乎完美自相关序列（APAS）在 NL 条件下的性质，包括偶数阶和奇数阶 NL 条件。我们还考虑使用计算算法在低相关区域 (LCZ) 内设计具有低自相关旁瓣的长二进制周期序列。计算优化序列 (COS) 不受序列长度限制，并且比其 APAS 对应物提供更高的多样性。我们在 NL 条件下比较了 COS 和 APAS。我们表明，这两种类型的序列都可以用来避免 NL 条件下范围轮廓中的鬼峰。