[SOLVED] RF - FiberOptic - RF Circuit

[von Moltke]

Hello all,

I am trying to see if the following is possibly realizable:

I need to design an 1 GHz BW RF Receiver in frequency range 0.1-18 GHz. I want to collect RF at Antennae and convert it to Optic then send it to Receiver and convert Optic signal to Baseband or if possible get the Time vs Amplitude samples. The attached file depicts my goals.

Anyone worked with RF/FO and FO/RF converters? How does the frequency(RF)-to-wavelength(Optic) mapping made? Would it be possible to make a frequency-wavelength mapping at the RF/FO stage so that for the wavelength that I convert down to baseband I will know the carrier frequency at the imput?

My question is:If this goal is achiehable with currently available RF/FO components and any sugestions based on educated guess or preferably experience?

Thanks all in advance.

 

[E Kafeman]

Is this in line with what you want to design: https://www.edaboard.com/threads/274966/#post1179598 ?
Other ideas in same direction: **broken link removed**

 

[jiripolivka]

Hello all,

I am trying to see if the following is possibly realizable:

I need to design an 1 GHz BW RF Receiver in frequency range 0.1-18 GHz. I want to collect RF at Antennae and convert it to Optic then send it to Receiver and convert Optic signal to Baseband or if possible get the Time vs Amplitude samples. The attached file depicts my goals. View attachment 92342

Anyone worked with RF/FO and FO/RF converters? How does the frequency(RF)-to-wavelength(Optic) mapping made? Would it be possible to make a frequency-wavelength mapping at the RF/FO stage so that for the wavelength that I convert down to baseband I will know the carrier frequency at the imput?

My question is:If this goal is achiehable with currently available RF/FO components and any sugestions based on educated guess or preferably experience?

Thanks all in advance.

The system you need is named RF over fiber. Check M/A COM company, they offer complete solutions as well as a white paper with details.
The ~1 GHz bandwidth can be directly sent over a fiber by modulating a laser or a LED. If you need to locate it to a carrier within 0.1 to 18 GHz, you may need a converter at the transmitter and/or at the receiver.

The fiber advantage is that contrary to RF cable or waveguide the loss is much lower. RF Over Fiber is now common in satellite terminals and microwave radios.

 

[biff44]

well, that is a big bandwidth (dc to 18 ghz). You CAN send that down a fiber, but it will not be an ordinary fiber transmitter and receiver, like an on/off laser diode. more complicated modulation.

Practically, you need to hook the antenna to an amplifier to boost the signal, and then send to fo modulator. But antenna is letting in dc-18 GHz, the amp will get overloaded. Need to band limit the input somehow. As Jiri suggested, if you downconvert to maybe 2-3 Ghz IF, and THEN send on laser diode, much easier! You can send LO frequency tuning digital info back up the fiber on a different wavelength.

 

[von Moltke]

Hello all,

I have done some market research and found a company that can partially meet our design reqirements. However, the carrier frequency data extraction is an issue to be dealt with and I asked for application notes on the RF Over Fiber companies but received no data so far.

Thank you all for your responses.