Text this: Symbol-error performance and bit-error performance of QAM signalling

 ______     _____     _  __     ___      _  __  
|      \\  |  ___||  | |/ //   / _ \\   | |/ // 
|  --  //  | ||__    | ' //   / //\ \\  | ' //  
|  --  \\  | ||__    | . \\  |  ___  || | . \\  
|______//  |_____||  |_|\_\\ |_||  |_|| |_|\_\\ 
`------`   `-----`   `-` --` `-`   `-`  `-` --`