I don't know what Wireless Router and Wireless card You are Using but I describe all the Troubleshooting Tips in General for all.
- See around if a Microwave Oven or other Same frequency spectrum in Air like Card less Phone, Wireless Phone,
- Login to your router settings http://192.168.1.1/ and user/pass is admin/admin for most of routers. and Make Surveys or Site Scan or Scan.. to see if there are some other Stronger Wireless signals with same Channels.
- IF you find any other Wireless Networks with same channel like you have configured in you Router then change Your Routers Wireless Channel ...
- Best channels are 1,6,11 to use these all are non overlapping channels.
- One very important thing normally people don't know or take under notice. See there are different Wireless Channels Allocation in different parts of the world.Now you got an Access Point(Router) with 14 Wireless channels and your Laptops also with 14 Wireless Channels. in Country Settings.But your PC Wireless Adaptor is with 11 or 13 wireless channels.........There is a difficulty and lower connectivity.Make sure same country wide settings on Router and Wireless Adaptor.Hope this all would solve your problem...
- You can check response time under different Packet values by using following CMD command. Go to RUN in your Start Menu... Type "CMD" without " " and hit the Enter button...Now you can see a black screen, There you have to type this command "ping 192.168.1.1 -t -l 65550" without " " and type it right after C:/documents user setting/user/ Where in command:192.168.1.1 (IP Address of Your Access Point)-t (Continues Ping)-l (Packet Size from 1 to 65500)
- Now you can check the actual connectivity and quality of link for a wireless network connection using different packet size...
This is very helping for beginners to learn about Link Quality and what is Max packet size handling for that Wireless Link.