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Multiple antennas and placement
I need some advice on single pole antenna placement.
I am developing a device that has two CC1101 chips that work on two different 900MHz ISM channels. These chips are connected to two single pole antennas that are currently held vertically with a horizontal separation of about 5-10cm and no vertical separation.
I need one chip to listen while the other continuously transmits. While doing so I’ve notice that the RSSI value of one antenna drops while the other is transmitting. I experimented with increasing the horizontal gap between the antennas and that seems to reduce the said drop in RSSI. I also notice that when the ISM channel spacing between the two antennas is increased the reduction is RSSI is again reduced.
I’d obliviously like to place the antennas in such a way that this reduction in the RSSI is minimized. I realize that I could just place the antennas as far apart as possible, but I am hoping that someone could give a more elegant solution; perhaps like a theoretically derived minimum horizontal separation distance or perhaps a different antenna layout all together?
One configuration for you to test would be to slant the antennas 45 degrees from vertical. Tx antenna slanted by +45, Rx antenna by -45, so their relative angle would be 90 degrees. Such an angle between antennas should give you a more than 30dB isolation between them.
Hope this helps
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