The present invention relates to a wireless communication system, and more particularly, to a downlink signal transmission and reception method and device taking into account antenna port relationship. The synthetic methods involve novel, efficient, and environmentally benign steps and procedures. The distance parameter indicates a distance from its associated vector, being in a first class, to the opposite class. A hollow core in the insulation material directly beneath the seed well provides cooling in the center of the growing crystal, which enables uniform, level growth of the crystal ingot and a flat crystal-melt interface which results in crystal wafers with uniform electrical properties.