Received signal strength indicator

Cellular signal strength of -74dBm (or 66 asu) displayed on a smartphone. Also shown: signal bars of two cellular networks, and signal bars of a Wi-Fi network.

In telecommunications, received signal strength indicator or received signal strength indication[1] (RSSI) is a measurement of the power present in a received radio signal.[2]

RSSI is usually invisible to a user of a receiving device. However, because signal strength can vary greatly and affect functionality in wireless networking, IEEE 802.11 devices often make the measurement available to users.

RSSI is often derived in the intermediate frequency (IF) stage before the IF amplifier. In zero-IF systems, it is derived in the baseband signal chain, before the baseband amplifier.[3] RSSI output is often a DC analog level. It can also be sampled by an internal analog-to-digital converter (ADC) and the resulting values made available directly or via peripheral or internal processor bus.

  1. ^ "Usage of received signal strength indicator v. received signal strength indication in literature". Google Ngram Viewer.
  2. ^ Martin Sauter (2010). "3.7.1 Mobility Management in the Cell-DCH State". From GSM to LTE: An Introduction to Mobile Networks and Mobile Broadband (eBook). John Wiley & Sons. p. 160. ISBN 9780470978221. Retrieved 2013-03-24.
  3. ^ Foerster, Anna; Foerster, Alexander (2011-02-07). Emerging Communications for Wireless Sensor Networks. BoD – Books on Demand. p. 241. ISBN 978-953-307-082-7.