sunshineh wrote OK, I understand. But can I use this port also as switch directly? Yes.

No, there are no antennas possible, just APs (often, people call those APs and even the CPEs just "antennas"). For example, you can add a TL-WA901ND, a fine AP for indoor use, by connecting it to the...

Mount it outside to have free line of sight between the two CPEs in order to improve the signal strength which is somewhat low for 110m. Then reduce TX power to see whether SNR could be improved...

You could add any wireless access point (AP) with omnidirectional antennas to the LAN1 of a CPE to extend the WiFi coverage of the same subnet, sure.

See my answer at: http://forum.tp-link.com/showthread.php?99343-Application-question-using-2-CPE210&p=211332&viewfull=1#post211332 It's not that easy to re-broadcast WiFi from a hotspot, it strongly...

Set your PC to a static IP in the 192.168.0.x range, say 192.168.0.12, and try again. Then assign a free IP from the 192.168.1.x network (say, 192.168.1.2 or whatever is an unused IP in your network)...