Frequency hopping sequences (FHSs) are employed to mitigate the interferences caused by the hits of frequencies in frequency hopping spread spectrum systems. In this paper, four new constructions for FHSs are presented, including a direct construction of FHSs by using cyclotomic cosets and three extension constructions of FHSs by using units of rings and multiplicative groups of finite fields. By these constructions, a number of series of new FHSs are then produced. These FHSs are optimal with respect to the Lempel-Greenberger bound.

中文翻译：

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最优跳频序列的新结构

跳频序列（FHS）用于减轻跳频扩频系统中频率命中引起的干扰。在本文中，提出了四种新的 FHS 构造，包括使用分圆陪集的直接构造 FHS 和使用环单元和有限域乘法群的 FHS 的三种扩展构造。通过这些结构，随后生产了一系列新的 FHS。这些 FHS 就 Lempel-Greenberger 界而言是最优的。