Power divider and directional coupler.

[hamradio.9m]

Hi,

I will use this device to devide one RF data channel (720 MHz) into two channels. This two channels will belongs to spectrum analyzer (for monitoring) and demodulator.

As far I concern, power divider accepts an input circuit and delivers multiple signals outputs maintaining the phase and amplitude. There are also hybrid varieties that could split signal into different phases maintaining the amplitude.

So what is the different between power divider and directional coupler(pros/cons)? What is the best solution that you could suggest? Is't a big different between this two devices in term of link performance and cost.

Thanks in advance !

Friendly.

 

[masadi]

Re: Power divider, Combiner, coupler and splitter

check this FAQ

u can use wilkinson's power divider.

 

[Euler's Identity]

In my experience, a hybrid splitter/combiner shifts the phase by 180 but keeps the amplitudes fairly closely matched (assuming it's being used at the correct frequency); whereas a directional coupler generally has one output a fixed number of dB lower than the other -- plus some will have another output near the input which willl yield the return loss number, referenced to the output tap. I used dierectional couplers to tap off to a spectrum analyzer through yet more padding. Also, there is minimal power loss through the directional coupler, relative to the splitter/combiner.

Hence, if you want to power divide, you should use a splitter such as the Wilkinson Hybrid splitter/combiner, but remember that you are going to get a phase shift. Therefore, to repair the phase you are going to need to, I guess, adjust your line length. Or, perhaps, you could send one output into a pad and the other into another hybrid splitter with a dummy load, in order to correct the phase and maintain matched power levels.

Bear in mind though that I am no RF engineer ;-)