increase range on home net with Belkin router

Hello, new here. How do I increase my wireless range, just slightly, from my Belkin wireless router F5D7230? It drops from excellent(or strong)to poor signal just as I enter our back room carrying my laptop, which has wireless built-in. When I reach the sitting area, internet reception is quite slow with the poor strength. I'net usage is mainly what I use the network for. Thanks for help. s