The concept of balancedly splittable orthogonal designs is introduced along with a recursive construction. As an application, equiangular tight frames over the real, complex, and quaternions meeting the Delsarte–Goethals–Seidel upper bound are obtained.

中文翻译：

---

平衡可拆分的正交设计和等角紧框架

引入了平衡可拆分正交设计的概念以及递归构造。作为应用，获得了满足 Delsarte-Goethals-Seidel 上限的实数、复数和四元数上的等角紧框架。