| 摘要 |
<p>An isolating circuit (100, 150) in order to isolate a first frequency signal in a first frequency range and a second frequency signal in a second frequency range which is higher than the first frequency range, has as antenna (113, 163) terminal, a first filter (101, 151) and a second filter (107, 157). The first filter, having a first input terminal (103, 153) and a first output terminal (105, 155), is coupled to a first input signal including the first frequency signal at the first input terminal and attenuates first frequency compornent of the first input signal below the first frequency range at a first attenuation rate and second frequency compornents of the first input signal above the first frequency range at a second attenuation rate. One of the first input and output terminals of the first filter is coupled to the antenna terminal. The first filter further has a first setting terminal setting the first attenuation rate and second attenuation rate so that the second attenuation rate is greater than the first attenuation rate. While the second filter, having second input (109, 159) and output terminals (111, 161), is coupled to a second input signal including the second frequency signal at the second input terminal and attenuates third frequency compornents of the second input signal below the second frequency range at a third attenuation rate and fourth frequency compornents of the second input signal above the second frequency range at a fourth attenuation rate. One of the second input and output terminals of the second filter is coupled to the antenna terminal. The second filter further has a second setting terminal setting the third attenuation rate and fourth attenuation rate so that the third attenuation rate is greater than the fourth attenuation rate.</p> |
