|
|
英文是找到的对diplexer和duplexer的区别介绍。
What's a diplexer? It's a three-port network that splits incoming signals from a common port into two paths (sometimes called "channels"), dependent on frequency. A diplexer is the simplest form of a multiplexer, which can split signals from one common port into many different paths. The incoming signals must be offset in frequency by an appreciable percentage so that filters can do their job sorting them out.
A diplexer could be used to route signals to two different receivers, based on frequency. Or it could be used to create a "matched" filter that is non-reflective outside of the intended passband. It could also be used as a bias tee, to feed your favorite active device with DC power.
Don't confuse the word diplexer with duplexer, which is the three-port network that permits a transmitter and receiver to use the same antenna, at essentially the same frequency. Duplexers are often used in radar, because the transmitter and receiver commonly share an antenna, and the returned signal doesn't vary much from the transmitted signal in frequency (just shifted slightly by the Doppler effect).
Important properties of a duplexer are：
Low loss between transmitter and antenna in transmit (less than 1 dB is desirable)
High isolation from transmitter to receive in transmit (as much as 80 dB for megawatt systems)
Low loss between antenna and receiver in receive (less than 1 dB is desirable)
Fast switching between the transmit and receive state, sometimes "automatically switched by the transmit signal, sometimes by command signal.
可见，diplexer的原理很明显，如图所示，
但是据英文所讲duplexer的重要特点，很像一个TR开关或者环形器。
但是这么高的隔离度环形器或者开关又不太好做到吧，对于大功率的开关的开关速度可能也无法满足。
有高手能解释下吗？最好能画个原理图出来，谢谢啦！ |
|
IP卡
狗仔卡
发表于 2010-10-30 20:15:03
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡