Hi,
I'm currently designing a wireless weather station/generic sensor system (I know it can be bought for a fraction of what the components and time will cost me, but I'm doing it because it is fun.). I'm wondering what is the best frequency to choose for this application. What I need is
20-30m of range, and ability to pass 1 or 2 concrete walls. I'll be using ready-made modules (not enough knowledge in RF to build my own from scratch), which I found for 433MHz, 868MHz and 2.4GHz. Which one should I choose considering ability to cross walls and possible interference from other systems ?Issue number two is the antenna, the only design I know is the 1/4 wave antenna, is there anything better I could build easily to improve the gain ?
Thanks.
vv.