相位传真 在 2006-1-10 12:26:47 发表的内容 沙漠之鹰兄说的很有道理,中间频段延迟小是如何测量出来的,是多大尺寸的导体? 这点我在怀疑,因为细线高低延伸都好,但中频会薄很多。 |
这是在一本威马写的教科书里的图片:),可惜这本书只涉及些皮毛,而不能给人一种大呼过瘾的快感。原文
Delay distortion is a phenomenon peculiar to guided transmission media. The distortionis caused by the fact that the velocity of propagation of a signal through a guided medium varies with frequency. For a bandlimited signal, the velocity tends to be highest near the center frequency and lower toward the two edges of the band.Thus, various frequency components of a signal will arrive at the receiver at different times.
这个观点应该是泛指一般频宽有限的导体(For a bandlimited signal)。要更深入的话(包括如何做时延均衡,这个我也很想了解),可能还是要找更高层的教科书,哈哈。不知道www.www有无?[upload=jpg]Upload/20061101185347697.jpg[/upload]