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ask for build 10GHz Local Oscillator ~~?

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petezhanghui

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Which IC~~choose ??
I need build a 10GHz Local Oscillator.


features:
(SSB)
100Hz __ -75 dBc/Hz
1KHz __ -95 dBc/Hz
10KHz __ -105 dBc/Hz
100KHz __ -115 dBc/Hz

~~~thanks!!!
 

The PN is very strict, so Hittite can't reach that. Do you need a single point freq or a span freqs?
 
thanks,
I need a single point freq,,,,,,,,,,,,,10GHz.
If you need a single point oscillation frequency, in this case don't consider VCOs...
Instead, consider DRO type discrete or module type oscillators because VCOs are noisy elements.
Especially varactor tuned DROs can be tuned in very narrow frequency bands and so silent devices..
 
thanks~ BIGBOSS
"Instead, consider DRO type discrete or module type oscillators"

Which IC~~choose ?????
 

thanks~ BIGBOSS
"Instead, consider DRO type discrete or module type oscillators"
Which IC~~choose ?????

isnt an IC .... do a google search on DRO 's to find out about them.

All Satellite LNC's use DRO's you could always retune the 10.7GHz one to the freq you need. wouldnt be too difficult
and as Bigboss hinted at they have very low phase noise :)

Dave
 
thanks~ BIGBOSS
"Instead, consider DRO type discrete or module type oscillators"

Which IC~~choose ?????
Dielectric Resonator Oscillators
You can check what it is but your PN requirements are very tight..
You'd better research some IEEE papers for design techniques because design a DRO is not easy and it's required an amount of EM simulation and practical implementation.
But as I said before, your PN requirement is very tight and you must use Bipolar Transistor to get this very low Close-In PN spec.( Because high 1/f noise of GaAs devices) But unfortunately, Bipolars are not so good at those frequencies and hard to find them.( Maybe custom designs..)..
Good Luck
 
thanks, Dave
thanks, BigBoss
Would you give me URL about some IEEE papers about DRO ?

you're welcome :) a google search will probably bring up some results for you

I use DRO's where stability isnt of high importance like in TV transmitter / receiver applications at 10 and 24 GHz
When the TV signal is ~ 8HMz or so wide, several 100kHz of drift isnt a real problem
DRO's can be phase locked and I have a 24GHz system that does that.

Another suggestion that no one has mentioned and I forget to..... you might want to consider YIG oscillators. They are available for many freqs and on ebay I have bought ones that cover 8 - 10GHz and 9.2 to 11.2 GHz. These are also able to be PLL'ed have a look at this example from ebay...
**broken link removed**

this is the same style as the units I have. YIG's also have reasonably good phase noise

Stellex’s YIG [Yttrium Iron Garnet] technology provides a frequency source with high spectral purity for high-frequency communications applications.
Mini-YIG Tuned Oscillators
• 9 GHz in Center Frequency
• Low Phase Noise
• –105 dBc/Hz @ 10K (typ.)
• –128 dBc/Hz @ 100K (typ.)
• Up to ±1 GHz Tuning Range
• Output Power +14.5 dBm (typ.)
• Outstanding Phase Hit Performance in 64 and 128 QAM Radio Systems
• Offered in SMA Connector Package


cheers
Dave
VK2TDN

---------- Post added at 10:11 ---------- Previous post was at 10:03 ----------

thanks, Dave
thanks, BigBoss

Would you give me URL about some IEEE papers about DRO ?

That link in Bigboss's last post will take you to an articl on DRO's and the bottom of the article are a lis of references that includes a number of IEEE papers

Dave
 
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