Use Power Amplifier in Input/Ouput?

Hey, I’m pretty new to radio hardware. I understand how radio waves work and I’m familiarized with transmitters and receivers but I still have some questions regarding other specific hardware like power amplifiers. I understand that PA just amplify the signal but I would like to know if they can be used in both input and output of receivers/transmitters. Theoretically there shouldn’t be any problem but I want to make sure that I’m right. Can they be used like this? And if yes, there are any specifications that I should check?

Sorry for the poor english.


Off topic but PA amplifier which boast the signal from pre amp mostly pre amp just couple of miliwatts going to feed the PA amp which boast your signal significant amount lets says 30 watts.

HF amplifiers different level but same idea most hf amplifier has 10-100 drive in to put 600 or more watts.

PA is short for power amplifier and is used in the transmit side. Depending on the input required to the PA in order to deliver the desired output, you may or may not also require a “driver” stage in between the LimeSDR and PA. For use outside the lab and particularly when using a PA, you will almost certainly need filtering also.

On the receive side you would have a low noise amplifier (LNA) or preamp — but not a PA. Likely filtering also to prevent aliasing.

Key considerations to take into account when selecting amplifiers include input/output levels and impedance matching. Higher order modulation schemes, such as used in cellular, will make additional demands. In all cases you must be careful to ensure that on the transmit side the driver, PA and filtering are selected to ensure that you meet applicable regulatory requirements and are not a nuisance to other spectrum users.

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Thanks for your reply, it’s really helpful. Do you recommend any resources for me to learn more about this?

Worth taking a look at the LimeSDR Workshop material and trying out the examples:

There is lots of more general information available online.