Spatial diversity uses multiple antennas that are

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Spatial diversity uses multiple antennas that are physically separated from one another. Pattern diversity uses two or more co-located antennas with different radiation patterns. Channel interference The 2.4 GHz frequency range is divided into 11 channels, with each channel having some overlap with the channels next to it. You might experience problems with your wireless network when other devices are trying to use the same or adjacent channels. There are also numerous devices that operate in the 2.4 GHz and 5 GHz ranges, which can create background noise and additional interference. Cordless telephones that operate in the 2.4 GHz range (900 MHz cordless phones do not cause interference) Other APs in the area (for example, each of your neighbors might have a wireless network, with each configured to use a similar channel) Microwave ovens Bluetooth devices Wireless game controllers To avoid interference, try changing the channel used on the AP. If the area has different wireless networks, configure each with a different channel, with at least two channels separating the channels in use (e.g., channels 1, 6, and 11). The strength of your Wi-Fi signal compared to the level of background noise is known as the signal-to-noise ratio (SNR). If the SNR is low, your wireless network will have problems with interference. Atmospheric and EMI conditions Interference from weather or EMI can degrade the signal and cause service interruptions. AP placement The location of the AP can affect signal strength and network access. Keep in mind the following: With omnidirectional antennas, radio waves are broadcast in each direction, so the AP should be located in the middle of the area that needs network access. Devices often get better reception from APs that are above or below. In general, placing APs higher up prevents interference problems caused by going through building foundations. For security reasons, APs should not be placed near outside walls. The signal will emanate beyond the walls. Placing the AP in the center of the building decreases the range of the signals available outside of the building. Antenna orientation For radio frequency wireless devices, the antenna orientation might have a small effect on signal strength. There are two types of antennas that are commonly used in wireless networks. Directional antenna o Creates a narrow, focused signal in a particular direction, which increases the signal strength and transmission distance o Provides a stronger point-to-point connection; is better equipped to handle obstacles Omnidirectional antenna o Disperses the RF wave in an equal 360-degree pattern o Provides access to many clients in a radius For other devices, such as infrared or satellite, the orientation of the receiving device is critical. For these types of devices, make sure the receivers have a line-of-sight path to communicate.
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