I am designing a prototype PCB which shall have 5 pluggable RF modules and one 4G LTE module as shown in the image
The Base board size shall be 240 x 140 mm, RF board size is 40 x 50 mm and LTE board size is 45 x 70 mm.
The 5 RF boards are identical and they operate in the 868 MHz band for short range communication. The center frequencies of successive RF boards shall be separated by 400KHz each (they use different channels in the band). The boards have transmit power capacity of 22 dbm.
The LTE module has a 3dbi antenna. All antennas are rubber duck type antennas. All the RF radios shall operate independent of each other.
The whole set (including antennas) shall be enclosed in a polycarbonate enclosure.
I tried looking at posts with the configuration like what I have, but I could not find any. I found couple of posts which talked about 2 or 3 radios on one board, but of different type and frequency bands.
My questions is as follows. Since all the radios are physically close to each other and operating independently (center frequencies of RF boards are also close to each other), will they cause issues at the receivers of each radio? Will the transmission from surrounding radios cause interference, saturation or reduction in data rate issues? Would any other issues crop up? Are there any specific points that I need to take care of?