Path Loss
Path loss between the transmitter and receiver is a key consideration when designing a wireless LAN solution. Expected levels of path loss, based on the range between the transmitter and receiver, provide valuable information when determining requirements for transmit power levels, receiver sensitivity, and signal-to-noise ratio (SNR). Actual path loss depends on the transmit frequency, and it grows exponentially as range increases between the transmitter and receiver. With typical indoor applications, the path loss increases at approximately 20dB every 100 feet. Keep in mind, though, that multipath propagation can cause signal fading, which effectively increases path loss. The primary method for countering the effects of path loss is to utilize additional access points to provide adequate coverage throughout the facility where the wireless LAN will operate. Be certain to perform an RF site survey of the facility where the wireless LAN will be located to determine the number and location of access points.