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UWB mixer

 
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oabedi



Joined: 06 Aug 2008
Posts: 12
Helped: 3
Post21 Aug 2008 3:03   UWB mixer
May I ask:
-Why we need mixer in UWB or any wideband system?
-NB system, requires Mixer due to reduce filter Q factor but for UWB, Q factor will be 3-5, which is low enough for relax design.

Thanks
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Abhishekabs



Joined: 12 Jan 2007
Posts: 515
Helped: 64
Location: India
Post21 Aug 2008 5:18   UWB mixer
The use of mixer is for frequency conversion (down convert or upconvert)
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oabedi



Joined: 06 Aug 2008
Posts: 12
Helped: 3
Post21 Aug 2008 6:09   UWB mixer
you are right, but we use mixer to relax LPF with Lower Q in NB system.
Without mixer it will be impossibl. But in UWB we don't have this problem...
LPF Q, will be low which is doesn't require any Mixer.(I think)
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Abhishekabs



Joined: 12 Jan 2007
Posts: 515
Helped: 64
Location: India
Post21 Aug 2008 6:22   Re: UWB mixer
See the image attached

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RF-OM



Joined: 03 Aug 2007
Posts: 607
Helped: 113
Location: The Earth
Post21 Aug 2008 22:46   Re: UWB mixer
There are a lot of different UWB technologies and not all of them require frequency conversion. For example, I am doing a lot of UWB designs without mixer.

Mixers should be avoided wherever is possible because it is probably the most vulnerable to any interference and non-linear part of the RF system. Conversion usually use to simplify amplification and filtration of the receiving signal as well as have these parameters equal across the whole band. Reducing required Q is not the primary direct reason of mixer usage. There are other ways to change the Q.
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