Hi, so I’m struggling to find a thread that currently exists if it does through the search, but I’m trying to build a controller that works somewhat like pulsed Doppler radar, but with three channels that are relative to one another.
I believe I need to use 3 tied pwm controllers to act as a switch for 3 separate frequency generators. Each channel will operate on 33.33% duty cycles in khz range and each “on” will need to be a changeable set frequency in the microwave range. Final signals out can be in mV
Pulsed frequency illustration:
—-llll——llll—— ch 1 out
——-llll——llll— ch 2 out
-llll——llll——llll ch 3 out
Time>>>>>>>>>
I just don’t know where to start. I feel like using arduino is the right direction. Any input is greatly appreciated! Thanks! As a side note. I don’t know any programming.
I understand how Doppler works, but why three channels? What sensor do you use to detect the Doppler shift? And Why 3 channels? The microwave output of a single channel will wipe out a nearby receiver for the other channels.
The output signals are very very weak. A max strength of 1 volt rms and max amperage of 10mA. I was using radar as a comparison to the signal output form, but I may have botched the description. Im not actually building a radar transmitter/receiver. Just three pulsed signal generators/transmitters. I’m looking to pulse a high frequency(microwave) at a lower frequency(1khz-.5mghz). And I want to be able to phase lock them from the same master clock.
I was thinking using a microcontroller to send square wave signals to three relays/MOSFETs that would kick on 3 signal generators circuit open. However bc of the high frequency of pulse, there would need to be a really fast response time from the frequency generator which may limit the pulsed signal frequency. Thinking maybe to have the signal generators always on/generating and use mosfets as a switch to toggle the signal being dumped to outgoing components and an impedance matched resistor.
I found a great link for multiple ways to go about achieving this on a more sophisticated level I may go this way instead but mine seems more simple bc I can understand it better so I think I’ll start with that. Anyway if anyone is interested they can find it on “microwaves101” website
You’ll have to check into the earlier part of this thread bc I was clear that the output would be very minuscule. Nothing even close to needing a license or informing the feds I’m not that cool, nor do I have the time and money. This is all small scale hobby lab experiments buddy.
