I have not tried this. It seems to be better to send a require email to support@tp-link.com and confirm this. As far as i know, the MR3220 can not repeat wireless signal.

It sounds weird.. When your netbook wakes up, you can still ping the gateway (192.168.0.1) and also the Public address from ISP. This means the netbook is connected with the router well and it is...

I don't see HUAWEI EC315-2 on the router's compatibility list. Probably, these two have compatible issue...

Who is them? How can I contact them to solve my problem?

How about this: Switch the hardware mode switch to 3G, connect the 3G USB modem to the router and connect MR3020 from its ethernet port to the dual-WAN router's WAN port.

It seems the WDS bridging is set up successfully. Just confirm with you: Samsung TV is connected to the MR3220 via a cable or wirelessly? Well, the Samsung Smart TV is able to get a proper IP address...