Good evening, in the middle of a project(already asked some questions about it in this forum), its a small sensor "node" with an Atmega256RFR2 and some humidity, light, temperature sensors.
After a ton of code, its working fine, but the suggested SMD antenna gives an awfull small range(about 5-6m with transmit power on full tilt), I will admit my RF knowledge is about zero or maybe even negative, I only followed the datasheet for the recommended balun and antenna from the Atmel datasheets/app notes.
After trying some random caps and inductors to tune the thing with even worse results, I just unsoldered the SMD antenna, cut a patch antenna from a laptop with about 10cm of coax wire, soldered it to the balun and scratched a bit of the solder mask near it for the ground and got a much, much better result of 150m LOS, was baffled by the range with the random laptop antenna.
Now, I'm going for rev 0.2 of the board, and I dont know what to do regarding the antenna :/
SMD antennas with gain are kinda rare from what I could find searching around Mouser, almost all have +/- 0.5dBi of gain, that with my RF skills will net me again some 5m range boards, another option would be so just put an u.FL connector and buy some laptop patch antennas from molex or someone that sells them and just glue the antenna to the box, given that all I have is a couple multimeters and a 100Mhz scope, antenna tunning/matching is more or less impossible for me..
Any ideias about antennas, or maybe it was all fault from my layout?
The parts used are:
balun: 2450BM15A0015
SMD Antenna: 2450AT42B100
Print screen of the pcb: