5.1.1 Frequency Response Phase and Group Delay The phase angle of any complex number is not uniquely defined,since 2nr can be added without affecting the complex number. H@)HH(eYeKMoy2nrHF1(@wY-Hm) ◆denote Principal Value(主值)of the phase of H(eo) -π<ARG[H(eo]≤π ambiguous phase不确定的相位 arbitrary ∠H(eo）=ARG[H(e]+2rr(o where r(@)is a positive or negative integer that can be different at each value of o. 115.1.1 Frequency Response Phase and Group Delay ◆The phase angle of any complex number is not uniquely defined, since 2πr can be added without affecting the complex number. ( )  ( ) 2 ( ) H ej H j ARG e r   = +     ( ) H ej ARG  −     ◆denote Principal Value(主值) of the phase of ( ) H ej ambiguous phase 11 where is a positive or negative integer r() 不确定的相位 ( ) ( ) ( ( ) 2 ) j j j j H e r H e H e e     +  = ( ) j ( ) j j H e H e e    = arbitrary that can be different at each value of 