I am a software developer who knows a bit about electronics and very little about RF. I am trying to understand how to interpret the various signal strength and quality values which can be obtained from the SARA R410M-02B (NovaM). Of course, this topic is not specific to any particular module…
Okay, the three measures that I routinely see (and the NovaM) can provide are:
RSSI: Received Signal Strength Indication (expressed in dBm, decibels/milliwatt)
RSRP: Reference Signal Received Power (expressed in dBm)
RSRQ: Reference Signal Received Quality (expressed dB)
Since I do not understand the nature of any of those measures, please correct me where I am incorrect…
RSSI is more general than RSRP in that RSRP is LTE specific and RSSI is a measure which is also meaningful regarding GSM (and other) technologies.
RSSI and RSRP are both indicating the strength in some way of the signal measured at the antenna.
RSRQ is a measure of signal “quality.” I don’t really know what that means.
I notice that RSSI and RSRP generally “move together.” That is, when RSSI goes up/down from one reading to another, RSRP tends to move in the same direction.
This is not the case for RSRQ. RSRQ may go up from one reading to another while RSSI/RSRP move in the same or opposite direction.
I suspect that RSRQ is affected by traffic. That is, with more network demand RSRQ may go down, regardless of signal strength (RSSI/RSRQ). Is this correct?
I’ll be very grateful if someone who really understands this subject to offer a bit of education.
Thanks in advance…