Sometimes, however, it is better to replace the router's built-in antenna with a different one. An omnidirectional antenna can have difficulty reaching a long distance because its signaling power must be expended in all directions. To address this problem, some router manufacturers sell external omnidirectional antennas that are significantly stronger than the router's built in antenna. Installing a stronger omnidirectional antenna obviously allows far-away locations to be better reached. Additionally, because Wi-Fi connections are distance-sensitive, a stronger connection also often leads to increased network performance.
A wireless antenna that is too strong, however, can create network security issues. Use of omnidirectional antennas can result in Wi-Fi signals that bleed outside a house into neighboring areas where the radio signals can be snooped. Alternatively, greater Wi-Fi range can also be achieved with a high gain directional antenna that increases signal receptivity in a particular direction. By focusing the signal, a high gain antenna allows the signal to be better controlled, literally aimed toward the area of the home where wireless devices are located.
In summary, consider replacing the wireless antenna on a router to improve wireless network reach and performance if possible. Many routers support an external antenna jack that allows connecting the new antenna. Consult the router product documentation for details.