It produces the I and Q signals, limits their pass bands, uses them to modulate the subcarrier in a quadrature and adds the moduled subcarrier to the luminance Y, blanking and synchronizing signal waveform.

• 它首先分离出I信号和Q信号，指定了它们的传输频带，并用它们对副载波进行正交调制，然后将调制过的副载波信号叠加到亮度信号Y和同步信号波形上。