Antenna + Frequency Multiplier

[Adam Dewbury]

Is it possible to have a simple set up of an antenna receiving 2.4GHz, passing through a passive frequency multiplier (given the RF wave has sufficient power to drive the component) to be doubled and then re-emit the doubled frequency from the same antenna?
Thanks.

 

[davenn]

Is it possible to have a simple set up of an antenna receiving 2.4GHz, passing through a passive frequency multiplier (given the RF wave has sufficient power to drive the component) to be doubled and then re-emit the doubled frequency from the same antenna?
Thanks.

hi, Adam
welcome to EP

a few concept problems there
1) .. the 2.4GHz receive antenna wont work at twice the freq
2) .. after doubling the power received by the 2.4GHz antenna there will be next to nothing in the way of signal ... not enough for anything useful


so what are you really trying to achieve .... tell all



Dave

 

[Adam Dewbury]

Thanks.

2.4GHz was chosen as an FCC unlicensed band, I can look at other frequencies, this was just my preference.

I was looking at designing an antenna that would achieve resonance at 2.4GHz, surely at 4.8GHz it could still hit resonance as it's a half wavelength?

I want to send out a RF signal and have it received, doubled and emitted to be detected over a range of 5m/15 feet using passive components. It would serve as a simple locator.

 

[davenn]

2.4GHz was chosen as an FCC unlicensed band, I can look at other frequencies, this was just my preference.

yup, no problem there

I was looking at designing an antenna that would achieve resonance at 2.4GHz, surely at 4.8GHz it could still hit resonance as it's a half wavelength?

but 4.8 GHz ISNT an ISM band allocation ... 5.8GHz is the next one that is

I want to send out a RF signal and have it received, doubled and emitted to be detected over a range of 5m/15 feet using passive components. It would serve as a simple locator.

OK ... for the transmitter ......
What is transmitting the power ?
how much power ?
what sort of antenna ?
what distance is it likely to be from the passive repeater ?

for the receiver ....
You said around 5m from the repeater
what is the receiver ?


The real issue is the lack of power that would be going into the multiplier. It's likely to be in the order of microWatts.
Without amplification, there just isn't going to be enough signal level to drive a multiplier


In my ham radio activities, I have played with passive multipliers quite a lot. Used a special type of diode called a varactor
used them to triple 144MHz to 432 MHz and others to triple 432MHz to 1296MHz. 40% efficiency is about the avg. that can be expected
I and fellow hams would feed them with around 10 to 12Watts on 144 or 432 and get around 5W on 432 out or 4W on 1296


Dave