Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Received signal strength indicator
open-in-new
<p>In <a href="/facts/Telecommunications/vxoj1cxR">telecommunications</a>, received signal strength indicator or received signal strength indication (RSSI) is a measurement of the <a href="/facts/Electric_power/w61ID9yQ">power</a> present in a received <a href="/facts/Radio/XFr909M2">radio</a> signal. </p><p>RSSI is usually invisible to a user of a receiving device. However, because signal strength can vary greatly and affect functionality in <a href="/facts/Wireless_LAN/ooq0WA45">wireless networking</a>, <a href="/facts/IEEE_802.11/ryEGu6Vq">IEEE 802.11</a> devices often make the measurement available to users. </p><p>RSSI is often derived in the <a href="/facts/Intermediate_frequency/9mPpJtSA">intermediate frequency</a> (IF) stage before the IF amplifier. In <a href="/facts/Direct-conversion_receiver/flQEkvm6">zero-IF systems</a>, it is derived in the baseband signal chain, before the baseband amplifier. RSSI output is often a DC analog level. It can also be sampled by an internal <a href="/facts/Analog-to-digital_converter/8YYNsMFg">analog-to-digital converter</a> (ADC) and the resulting values made available directly or via peripheral or internal processor bus. </p>