A new method for generating the quadrature GMSK signal

called Direct Decomposing Modulation Phase(DDMP)

is presented.The integrated phases of the Gaussian filtered pulse response are turned into two parts:the transient part and the stable part

and the construction of the two parts are analyzed in detail.The transient part is relative only to several near input data bits

its states being finite

which means the transient part can be made into a table to be stored into a EPROM.Although the stable part is relative to the history of all the input data

the triangle function values of it are ±1

which only cause the sign of the transient part changing.A realization scheme for generation of I-Q GMSK signal is designed.The simulating results validate the method

and the wave and the spectrum of the GMSK signal can be measured up to the GSM standard.