| 摘要 |
PURPOSE:To obtain the best reception signal at all channels by securing the equal shope for the frequency characteristics of the phase variation between the 1st feeding means possessing several units of the signal process circuit provided in correspondence to each channel and the 2nd feeding means. CONSTITUTION:Branching filter 8 is connected to output terminal 6a of antenna 6 among antennas 6 and 7 which features the same or nearly same characteristics. Then the output branched to several channels is supplied to phase shifters 9a, 9b... and variable attenuators 10a, 10b... which are connected in series to form the signal process circuits, and the output of these shifters and attenuators are mixed up in mixer circuit 11. While feeding means 13 connected to antenna 7 consists of the delay means which causes the slope of the frequency characteristics of the phase variation which is nearly identical to the slope of the frequency characteristics of feeding means 12's phase variation. The output of feeding means 12 and 13 are applied to mixer 14 to be mixed and delivered. In such way, the optimum directivity with the ghost disturbance eliminated can be obtained with every channel, and at the same time the flat frequency characteristics is ensured for the output amplidutde. Thus the lowering of the picture quality and the color fading can be avoided. |
