| 摘要 |
PURPOSE:To extract easily a leaked carrier wave component by connecting a high pass filter suppressing a low frequency component of two multivalue orthogonal signals to the transmission side in the Q (quadrature) AM transmission system using the leaked carrier wave. CONSTITUTION:A DC offset voltage Vdc is applied to any of I system data DIin or Q system data DQin, e.g., to the I system data in a transmission system 100, causing a leaked carrier wave in a modulated signal. High pass filters 105, 106 suppress a low frequency component in the signal component in order to extact easily the leaked carrier wave at receiving. A receiving system 200 extracts the leaked carrier wave by a band pass filter 222 and the carrier wave is applied to mixers 203, 204 for demodulation. The I and Q system data demodulated by the mixers 203, 204 are applied to low pass filters 207, 208 having complementary relation with the transmission system filters 105, 106, causing the suppressed low frequency component to rise level. |
