Wireless Speed

[YodaHulk]

I have a Linksys WRT54GL wireless router and am using a Dell XPS L502 laptop with Windows 10 Home. If I plug my laptop directly into my cable modem I get speeds of 70mb plus, but when using wireless I get less than 10mb. Any ideas? Are there any Windows 10 settings I need to configure to get better speeds? I realize the router isn't the best, but from what I've read online I should be getting 20mb plus at least.

Thanks