可以買一對Power line adapter....

比如

http://www.newegg.com/Product/Product.aspx?Item=N82E16833704200&cm_re=power_line_networking_adapter-_-33-704-200-_-Product

http://www.newegg.com/Product/Product.aspx?Item=N82E16833181529&cm_re=power_line_networking_adapter-_-33-181-529-_-Product

 

一頭接router，另一頭接各種設備，包括Wifi Access Point