I need help for TX and RX antenna in TRX system.
How to place antenna in uhf band?
How much isolation between TX and RX antenna?
Is the TX antenna influence in RX or not?
Why not elaborate the question? What do you try to achieve, why do you require isolation between RX and TX antenna? Do you intend half or full duplex operation?
More distance between the antennas, possible anechoic absorbing material to reduce leakage, reduce near field reflections ... it really depends on your setup and other antenna requirements.
I don't want to sound rude; but as the one who wants help; you need to give us a better description of your situation; so we can help you without giving you misinformation.
1- if possible show us a picture of your setup
2- is Tx and Rx antenna in same PCB, or are they on different planes i.e (distance between them) ?
3- What is the Frequency, Bandwidth (narrow or wideband antennas) and antenna type etc.?
1- I can't take a picture. The antenna (RX and TX) installed on tower and have 5m distance between them and the cable length is about 20m and then connect to Device.
2- Yes, Both of them in same PCB.
3- UHF band with narrow bandwidth. and antenna type is omni like as "Laird Technologies FRX450 450-470 MHz 5dBi Fiberglass Omni Antenna"