Yes. If your local Wi-Fi network performance is suffering it's usually your router that's the problem. You can upgrade your Wi-Fi performance by adding a new router to your existing modem (or existing combined modem-router, depending on what has been supplied by your ISP). Most wireless routers only have the capability to create and connect to local wireless networks. You still need your modem to connect to the internet. Usually your modem is supplied by your ISP (though this is optional).