RSRP RSRQ RSSI in LTE

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Reference Signal Received Power (RSRP), is defined as the linear average over the power contributions (in [W]) of the resource elements that carry cell-specific reference signals within the considered measurement frequency bandwidth.
A minimum of -20 dB SINR (of the S-Synch channel) is needed to detect RSRP/RSRQ




Reference Signal Received Quality(RSRQ): It is defined as quality of the received reference signal.
Quality considering also RSSI and the number of used Resource Blocks (N) RSRQ = (N * RSRP) / RSSI measured over the same bandwidth
The RSRQ measurement provides additional information when RSRP is not sufficient to make a reliable handover or cell reselection decision. 


RSRQ distribution in a live network



Received Signal Strength Indicator (RSSI):It is the linear average of the total received power (in [W]) observed only in OFDM symbols containing reference symbols for antenna port 0, in the measurement bandwidth, over N number of resource blocks by the UE from all sources, including co-channel serving and non-serving cells, adjacent channel interference, thermal noise etc.

 RSSI (wideband

power) = noise + serving cell power + interference power.

where Pi
Total = total received wideband power in the ith symbol

When 100% down link PRB is active without noise and interference, RSSI=12*N*RSRP, where
N is number of RBs across the RSSI, which is measured and depends on the bandwidth


under full load (100% PRB utilization) and high SNR

RSRP (dBm)= RSSI (dBm)- 10 * log (12 * N)

RSRQ = (N * RSRP) / RSSI

Example: RSRP=−82dB, RSSI=−54dB, N=100 => RSRQ=10lg100 + (−82)−(−54)=−8dB

 RSRP versus RSSI for full loaded cell (10MHz).

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