There are two lines of attack, and they are complementary. One depends on your brain; the other depends on your wallet.
For wireless network routers as well as real estate, the mantra is location, location, location. The most important thing to remember is that the RF radio signals that power wireless data networks work best when there's an actual line of sight from the transmitter (the router or access point) to the receiver (your laptop). In any real office that line of sight will be interrupted by walls, floors, bundles of cables, lighting installations, mainframe computers, telephone closets, file cabinets, lunchrooms full of pesky microwaves that interfere with the signal and all manners of other junk -- but you can still optimize the line of sight by placing the router and the access points as high as you can above the floor and locating them in the clearest and least obstructed spots you can find. In the center of the office.
The next thing to consider is antennas. Most routers and notebook wireless adapters come with small, low-efficiency antennas. You can significantly improve your wireless network's range by upgrading to directional antennas at both ends of the wireless connection. Put the router as close as possible to the directional antenna to minimize signal loss.
It will come as no surprise that the strength of the transmitter in your router is very important -- and "business-grade" routers and access points have the most powerful transmitters. Money spent here will make a noticeable difference.
That said, here are 10 tips for boosting the range and strength of your wireless network:
1. Upgrade routers and wireless network adapters to (interim) 802.11n. Ever since January 2004, when the IEEE announced that it had formed a task group to develop a new flavor of the 802.11 standard for wireless local-area networks - 802.11n - customers have been demanding to buy the new hardware. Why? Even though the standard is not due for final approval until July 2007, it promises to deliver far greater range and throughput -- up to 50 times greater than b-standard, and 10 times greater than the a- or g-standard. Of course all interim n implementations are backward-compatible with some or all of the current flavors of 802.11 -- but if you introduce an a-, b- or g-standard client into an n-standard network, your hot new n-standard router will slow down. So upgrade wireless adapters and routers at the same time.
2. Move the router off the floor and keep it as far as possible from walls and metal objects. As we mentioned earlier, metal, walls and floors wreak havoc with your router's wireless signal. The more of these obstacles your router needs to punch through to reach your notebook, the worse the interference, and the slower your connection will be.
3. Place your router (or access point) in a central location in the office. If your wireless router is at one end of the office (or your home), the signal will have farther to go to reach the other end. Using a central spot splits the difference.
4. Upgrade your router's antenna. Most routers come with an omni-directional antenna --meaning that it broadcasts and receives in all directions with equal efficiency. If you don't know where your receiving notebooks will be, or if they are indeed scattered in a random 360-degree pattern, omni-directional is fine. However, if (as is most often the case) your router is near an outside wall, with most of the network computers in a 180-degree pattern in one direction only (that is, toward the opposite outside wall), you are wasting half of the router's signal. If you upgrade to a hi-gain directional antenna that focuses the wireless signals in only one direction, you can maximize the efficiency of the system by aiming the signal in the direction you need it.
5. Upgrade the antenna for your notebook's wireless network adapter. Wireless network signals must be received and sent reliably by your remote computer. Sometimes, even if your router is broadcasting effectively, your computer can't send a strong signal back. Most notebook wireless adapters use an omni-directional antenna. You can improve reception considerably by replacing your laptop's PC card-based wireless network adapter with a high-gain, low-cost, range-boosting adapter with an external antenna.
6. Check your wireless channel, and change it if necessary. Wireless routers use one of 11 possible channels to broadcast. If another wireless network nearby happens to be broadcasting on the same channel your router is using, both networks will experience severe loss of range and power. You can use the wireless software on your notebook to find out how many wireless networks are active in the area, and which channels each is using. If you discover that another network is using the same channel as your router, log into the router via your browser and use its built-in configuration screen to select an unused channel. Chances are your signal strength will improve significantly. (You don't need to adjust your notebook; it's designed to automatically detect the network's new channel.)
7. Invest in a wireless repeater. Or two. Wireless repeaters (or access points) extend your wireless network's range with no need to install additional wiring. Just buy one or more wireless APs, place them roughly halfway between your previous wireless access point and your computer, and power them on. Voila! You now have an instant boost to your wireless signal strength. There are many affordable wireless repeaters on the market; all the major vendors make them. If you buy one like Apple's Airport you can even use it to stream wireless music to your stereo at the same time you're extending your wireless range.
8. Update your router's firmware and your network adapter's drivers. Hardware vendors are always upgrading and improving their wireless equipment to increase range and performance -- and most of those upgrades are free. Check for new firmware updates at your router manufacturer's Web site, as well as the site of your wireless adapter card. Microsoft also updates the drivers that Windows uses to communicate with your network adapter. To get those updates, visit Microsoft Update and click "Hardware, Optional."
9. Reduce wireless interference. Cordless phones, microwave ovens, and other wireless electronics in your home or office can interfere with your wireless network. To improve reception, look for cordless phones and other electronics that use the 5.8 GHz or 900 MHz frequencies. They won't interfere.
10. Use equipment from a single vendor. While every router will work pretty well with every network adapter (assuming their respective flavors of 802.11 are compatible), you will often get better performance if you match a router and network adapter from the same vendor. Some vendors like Linksys offer a boost of up to twice the performance when you use their hardware exclusively.