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High Frequency counter with microcontroller

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I have a new task, I couldn't find an idea about where to start.

I need a high frequency (min 5 GHz) counter, inside or connected to a microcontroller. The microcontroller will tell when to start and stop, and will receive the counter number.

I couldn't find a microcontroller that runs on such speeds, and I need help to search and have some ideas how to do that.

Any help would be appreciated.

Thank you,
 

I never tried to find any thing working on such speed ,most likely you wont find something like this too.

But in general you can connect a counter with high speed to a uC but it will its own oscillator, it will only recieve the start stop signal from the uC .
You will be able to read the counter value at the uC speed only which means you will miss many counter values in between depending on the frequencies
 

Before you begin such an ambitious project read this:
http://www.leapsecond.com/pdf/an200.pdf

:cool:

---------- Post added at 01:28 ---------- Previous post was at 00:56 ----------

For a more precise measuring you may use the reciprocal frequency counting technique.
Period counting, also called reciprocal counting, uses the external frequency to determine the gatetime during which the reference timebase frequency is counted. This method can provide higher resolution than direct frequency counting using a high frequency timebase. Then use the microprocessor to determines the external frequency from the reference frequency and the number of counts of the external and of the reference during the gatetime.

The resolution of the measurement is better since in a normal counter the count will be out by ±1 Hz count whereas the reciprocal counter will be out by ±1 master clock cycle. Reciprocal counting is more difficult as you have to use floating point routines to work out the frequency but because the counter counts edges of a master clock the resolution is fixed in multiples of that master clock and not dependent on the input signal i.e. the frequency counter will show all digits regardless of the frequency of the input.
Click to expand...

http://www.best-microcontroller-projects.com/article-frequency-counter.html
 

Good one Mr_RF.

Here is a couple of my old favorite 70's lab equipment. A time Interval counter that could ,measure phase noise on a microwave transmitter and a 4GHz frequency converter... THe techniques used in the design were very advanced and patented. http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1974-06.pdf I cut my teeth on HP's fractional N synth methods back then. Keep in mind simple PLL's with dividers in the loop are horrible for phase noise. There are clever ways to avoid that. (tease)
 

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