In countries the licenses are issued in paired bands where one band is used for downstream and the other band is used for upstream transmission.The paired bands are usually separated by 100MHz.

• 有的国家是按成对的波段颁发使用许可的，其中一个波段用于数据下行，另一个用于数据上行，其之间的间隔通常为100兆赫。