[time-nuts] Injection locking interconnect

[Jim Lux]

On 6/28/12 3:22 PM, Magnus Danielson wrote:
> Bill,
>
> On 06/29/2012 12:07 AM, Bill Dailey wrote:
>> Guys,
>>
>> I am looking for info on injection locking.  I have been searching
>> around for info.  I found an article that probably answers my question
>> but I can't get to it.
>>
>> http://www.oldcitypublishing.com/FullText/JAPEDfulltext/JAPED2.1fulltext/11-24pp%20GC05-06%20%28Rajput%29.pdf
>>
>>
>> Can anyone give me a reference regarding the required
>> interconnection?  I understand the ho and why... I just am wondering
>> how you make sure locking occurs in the right direction.  In other
>> words the target oscillator gets locked to the injected signal and not
>> the other way around.
>
> If you have two oscillators of the same frequency, these may
> injection-lock to each other, in which case the injection locking causes
> mutual synchronisation, which is a little forgotten research field all
> on it's own.
>
> This is a great starting point on injection locking that fellow time-nut
> Bruce Griffith wrote and collected references for:
> http://www.ko4bb.com/~bruce/InjectionLocking.html
>

I've always wondered about injection locking a 2.45 GHz oven magnetron, 
and whether you could use it to do something like FM.  The magnetron is 
a pretty crummy source phase noise wise, but is that because of low Q 
(and the frequency is just unstable, which locking would help) or 
because the amplification mechanism is noisy (in which case locking 
doesn't help).  That is, is injection locking more like a MOPA or a 
locked power oscillator.

(we're talking oven magnetrons here, not radar magnetrons for doppler 
radar which are actually designed for injection locking, etc. )


There's an interesting paper out there using a bunch (half dozen?) 
magnetrons as a microwave weed killer, where they all locked to each 
other, so the power was appropriately combined with minimal loss.