WDS bridge is a considerable option. But not sure whether the netgear router can support WDS or not... I found this guide: http://www.tp-link.com/en/article/?faqid=440

Their FAQ section on their official website is very nice and helpful ! http://www.tp-link.com/en/article/?faqid=445:cool:

Can you login to the web-interface of the TL-SG5428 ? There should be some configuration options about bandwidth control or QoS things in the web-interface...

It seems that you want to extend the wifi signal of your root router ? So you can consider to set it up as a repeater. The following guide may help you: http://www.tp-link.com/en/article/?faqid=442...

http://www.tp-link.com/en/article/?id=174

They have the same SSID and wireless channel and security password ? If not, try it.