1. Position your wireless router, modem router, or access point in a central location
When possible, place your wireless router, wireless modem router (a DSL or cable modem with a built-in wireless router), or wireless access point (WAP) in a central location in your home. If your wireless router, modem router, or access point is against an outside wall of your home, the signal will be weak on the other side of your home. If your router is on the first floor and your PC or laptop is on the second floor, place the router high on a shelf in the room where it is located. Don't worry if you can't move your wireless router, because there are many other ways to improve your connection.
2. Move the router off the floor and away from walls and metal objects (such as metal file cabinets)
Metal objects, walls, and floors will interfere with your router's wireless signals. The closer your router is to these obstructions, the more severe the interference, and the weaker your connection will be.
3. Replace your router's antenna
Linksys high-gain antenna—they’re powerful and easy to install. Or shop for other high-gain antennas.
4. Replace your laptop's wireless PC card-based network adapter
Laptops with built-in wireless networking capability typically have excellent antennas and don't need to have their network adapters upgraded. These tips are for laptops that do not have built-in wireless networking. Wireless network signals must be sent both to and from your computer. Sometimes your router can broadcast strongly enough to reach your computer, but your computer can't send signals back to your router. To improve this, replace your laptop's PC card-based wireless network adapter with a USB wireless network adapter that uses an external antenna. In particular, consider a Linksys Wireless-N or Alfa USB Wireless adapter USB network adapter. These add an external, high-gain antenna to your computer and can significantly extend your wireless range.
5. Add a wireless repeater
Wireless repeaters extend your wireless network range without requiring you to add any wiring. Just place the wireless repeater halfway between your wireless router, modem router, or access point and your computer, and you can get an instant boost to your wireless signal strength. Check out the wireless-N repeaters from Linksys, Hawking Hi-Gain, ViewSonic, D-Link, and Buffalo Technology.
6. Change your wireless channel
Wireless routers can broadcast on several different channels, similar to the way radio stations use different channels. In the United States and Canada, these channels are 1, 6, and 11. Just as you'll sometimes hear interference on one radio station while another is perfectly clear, sometimes one wireless channel is clearer than others. Try changing your wireless router's channel through your router's configuration page to see if your signal strength improves. You don't need to change your computer's configuration, because it can automatically detect the new channel.
To find your router configuration page, consult this quick reference table, which shows the default addresses for common router manufacturers. If the address is not listed here, read the documentation that came with your router, or visit the manufacturer's webpage.
To view the list of default Username and Password for router models click here
7. Reduce wireless interference
Cordless phones, microwave ovens, and other wireless electronics in your home or office can interfere with your wireless network. Avoid wireless electronics that use the 2.4GHz frequency. Instead, look for cordless phones that use the 5.8GHz or 900MHz frequencies.
8. Update your firmware or your network adapter driver
Router manufacturers regularly make free improvements to their routers. Sometimes, these improvements increase performance. To get the latest firmware updates for your router, visit your router manufacturer's website.
Similarly, network adapter vendors occasionally update the software that Windows uses to communicate with your network adapter, known as the driver. These updates typically improve performance and reliability. To get the driver updates, follow the instructions for your operating system:
· Windows 7
· Windows Vista
· Windows XP
Visit Microsoft Update, click Custom, and then wait while Windows XP looks for the latest updates for your computer.
Install any updates relating to your wireless adapter.
9. Pick equipment from a single vendor
Compatibility can be a big problem, especially for two way transmissions. It may help to purchase your adapter and your router – everything, from the same company. Aside from that, some companies have embedded enhancements that improve speed or signal strength when everything is under the same brand.
10. Use handmade Extender
Apparently aluminum foil amplifies reception and transmission
References : microsoft , makeuseof