Transmitter RF Circuit

[Canooski]

Reference Transmitter

I am trying to design a small pcb board with antenna that will emit a sine wave that some antennas can use as a reference. I am a little unsure of how to go about this or what is the best way?

Should I use a VCO with an amplifier or will this not give me the stability I need? I would also like to change between frequencies within the 902-928 ISM band when needed.

Instead of this should I use a frequency synthesizer where the output is amplifier?

I also looked at the MAX2900 part however it has a differential RF output which I am unsure of how to realize with a whip antenna.

Thanks

 

[Canooski]

I need to make a transmitter circuit board that will attach to a drone and emit a constant sinusoid in the 902-928 ISM band. I would like to be able to adjust the frequency on occasion within this band.

Is the best way to realize this through a VCO and an amplifier or should I be looking at a synthesizer. I looked at the MAX2900 IC and thought maybe I could use this but it has a differential output and not sure how I would use this with the whip antenna I was planning on using.

 

[vfone]

MAX2900 should be fine for this application. You can use baluns at differential ports to get single ended.

https://www.digikey.com/product-search/en/rf-if-and-rfid/balun/3539019?k=16 mhz

 

[D.A.(Tony)Stewart]

You must specify stability of carrier. Often 1ppm is used with complex design.

 

[Canooski]

Anything specific I should know about Baluns? I will just hook this up to the MAX2900 differential ports and attach an attena on the other side of the Balun. Any circuitry in between these. I might need an amplifier. Looks like there is a decent amount of loss from a Balun.

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As stable as possible. I need to make phase measurements from this reference signal.

 

[Quark-elec]

1ppm is too tidy tolerance, ,I think 5 ppm is enough for this project.