Diagnostics and Troubleshooting
RLXIB-ICN ♦ 802.11n
User Manual
Industrial Client
Page 36 of 129
ProSoft Technology, Inc.
July 25, 2013
Determine and resolve sources of interfering electrical noise.
Add a repeater between radios that are not communicating.
3.6.1 Understanding Signal to Noise Ratio
All radio networks experience background "noise", known as Electromagnetic
Interference (EMI), which consists of such things as stray signals from other
radios on the same frequency, or random interference generated by non-radio
devices that "leak" or emanate EMI as a by-product or side effect of their actual
function. There are also natural sources of EMI, including atmospheric
disturbances and sunspots. The "snow" on an unused or distant television
channel, or "static" on a car radio when passing under high voltage power lines,
are two common examples of background noise.
Unwanted noise, or EMI, on a data network can cause data transmission errors,
or stop a radio network from functioning at all. Most modern devices, including
RadioLinx radios, are designed to prevent unwanted emanation of EMI from the
device. Radios are also typically designed to tolerate a certain amount of
interference from other devices, however when the amount of noise reaches a
certain threshold, typically within 10dB of a link's RSSI, the radio may be unable
to distinguish between wanted and unwanted signals.
The Main Diagnostics tab in the RadioLinx Configuration Manager shows the
current Signal to Noise Ratio (SNR) in dB. This data can help determine if there
is a signal that is interfering with radio communications. You can use this
diagnostic information during a site survey to check for RF signals already
present in an area, or to detect network issues caused by RF interference.