I have no idea how to do what you are talking about, could you tell me how to test this?
You can measure internal LAN traffic by sending files from PC1 to PC2 an vice versa. When 1 of these is wireless you can check hoe 'fast' your wireless connection is.
When you use dslreports.com you are using your WAN connection and this way you cannot see where the alleged problem is.
Example:
If you transfer files from wireless PC1 to wired or wireless PC2 you can see the speed the router has to offer. If this is very low, there can be a lot of situations causing this.
But when you test speed at dslreports.com, the error can also be with the speedtest itself, the ISP or the internet gateway device (modem).