Timing Analysis and Optimization of Quadrature Modulator
Xuliang Wang · Radio Engineering · 2010
Quadrature modulator is affected by the IQ imbalance and phase noise worse caused by the time sequence of modulator data in the project applications.When modulating with random data,the IF bandwidth is large after modulating,so the IQ imbalance and phase noise worse is not easy to find out.In this paper,in order to solve the above problem,with AD9957 working as quadrature modulator,the output of modulator using three kinds of input signals of static input,in-phase sinusoidal input and quadrature sinusoidal input is discussed,then timing is analyzed and optimized,and thus the IQ phase unbalance and phase noise of modulator are reduced.