It is a digital signal, usually a square wave, which will form a square envelope on the carrier.
It cannot be written as "3 15mHz". The lowercase "M" stands for "milli" and the uppercase "M" stands for "mega".
Guangzhou 1997- 1998 is prosperous. East Lake, North Park, South Park and Panxi have their own characteristics, and famous old brands such as Guangzhou Restaurant, Lia