rsrp

SINR

For field measurements

Only for internal use; Confidential document

Only for internal use; Confidential document

2 © Meritech.co.ltdFor internal use only

RSRP• RSRP is the power of a single resource element. • UE measures the power of multiple resource elements used to transfer the reference signal but

then takes an average of them rather than summing them.• RSRP. If receiver diversity is in use by the UE, the reported value shall not be lower than the

corresponding RSRP of any of the individual diversity branches.


RSRP reporting range

Microsoft Word Document


RSRQ

• RSRQ = RSRP / (RSSI/N)


RSRQ reporting range

• Impact of intra cell power to RSRQ:

Example for noise limited case (no interference):

If all resource elements are active and are transmitted with equal power then

RSRQ = N / 12N = -10.8 dB

(because RSRP is measured over 1 resource element and RSSI per resource block is measured over 12 resource elements)

When there is no traffic, and assuming only the reference symbols are transmitted (there are 2 of them within the same symbol of a resource block) then the RSSI is generated by only the 2 reference symbols so the result becomes;

RSRQ = N / 2N = -3 dB

Document explaining RSRQ reporting range details:


Field measurement parameters• Terminals are measuring from service cell:

RSRP RSRQ

Scanners are measuring from all decoded cells: RSRP RSRQ RSSI => Received Signal Strength Indicator(Wideband channel power) P-SCH and S-SCH RSSI Reference signal SINR

Mapping from RSRP/RSRQ to SINR needed


SNR• Comparing two equations

Case 1

Case 2

powernoiseKHzP

P

PRSRPSNR

REn

REn

REn

__15_

_

_

Case 1 Case 2

RSRP linear RSRP(dBm) SNR(dB) SNR(dB)1.0E-08 -50 75.21 75.213.2E-09 -55 70.21 70.211.0E-09 -60 65.21 65.213.2E-10 -65 60.21 60.211.0E-10 -70 55.21 55.213.2E-11 -75 50.21 50.211.0E-11 -80 45.21 45.213.2E-12 -85 40.21 40.211.0E-12 -90 35.21 35.213.2E-13 -95 30.21 30.211.0E-13 -100 25.21 25.203.2E-14 -105 20.21 20.171.0E-14 -110 15.21 15.083.2E-15 -115 10.21 9.781.0E-15 -120 5.21 3.663.2E-16 -125 0.21 -12.961.0E-16 -130 -4.79 #NUM!3.2E-17 -135 -9.79 #NUM!

powernoiseKHzP

P

RSRPSNR

REn

REn

__15_

_


RSRQ to SINR mapping RSRQ depends on own cell traffic load, but SINR doesn’t depend on own cell

load. Used Resource Elements per Resource Block (RE/RB) in serving cell is an input

parameter for RSRQ -> SINR mapping• Two cases:

Case 1: RSRP doesn’t contain noise power Case2: RSRP contains noise power

RSSI

RSRPNRSRQ

PxNRSRPPRSSI

RBsN

usedRBREx

xNPP

PP

PNRSRPSINR

Nxni

REnxNn

Nni

Nn

*

*

#

_/

12*

)12_(

__

12_

12_

xNn

Nn

NnNxn

Nn

PxNRSRPRSRQRSRPN

PNRSRP

PPxNRSRPRSRQRSRPN

PNRSRPSINR

_

12_

12_)12_(

12_

**

12*

**

12*

RSSI

RSRPNRSRQ

PxNRSRPPRSSI

RBsN

usedRBREx

xNPP

PP

NRSRPSINR

Nni

REnxNn

Nni

*

*

#

_/

12*

12_

__

12_

xRSRQ

xNRSRPRSRQ

RSRPNNRSRP

SINR

112

**

12*

Case 1: Case 2:


RSRQ to SINR mapping• Case 1 equation used, as

it is simpler

x=RE/RB

• 2RE/RB equals to empty cell. Only Reference Signal power is considered from serving cell.

• 12RE/RB equals to fully loaded serving cell. All resource elements are carrying data.

xRSRQ

SINR

112

RSRP vs. SNR

-15.00

-10.00

-5.00

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

-135 -130 -125 -120 -115 -110 -105 -100 -95 -90 -85 -80 -75 -70

RSRP (dBm)

SN

R (

dB

)

SNR

RSRQ vs SINR

-10.00

-5.00

0.00

5.00

10.00

15.00

20.00

25.00

30.00

-20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3

RSRQ (dB)

SIN

R (

dB

)

2 RE/RB

4 RE/RB

6 RE/RB

8 RE/RB

10 RE/RB

12 RE/RB


RSRQ to SINR mapping • Lab measurements matches well

the calculated results• Measured with Agilent scanner

RSRP RSRQ Reference signal SINR

• Cable connection between BTS and scanner

Attenuator used to reduce signal level

No traffic = only control chs and reference signals

Full traffic load = data send in each RB

SINR vs. RSRQ

-10

-5

0

5

10

15

20

25

30

35

-20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0

RSRQ

SIN

R

Measured - full traffic Caculated - no traffic Calculated - full traffic load Measured - no traffic

SNR vs. RSRP

-15

-10

-5

0

5

10

15

20

25

30

35

40

-140 -135 -130 -125 -120 -115 -110 -105 -100 -95 -90 -85 -80

RSRP

SN

R

Measured-full traffic

Calculated

Measured - no traffic


Coverage criteria for field measurements• Coverage criteria for field measurement can be estimated with link budget tool

Depends on UL and DL parameters• Typical coverage requirement is that 95% of the measurement samples is fulfilling the criteria. (depends on

operators coverage requirements)

Example, outdoor coverage:• Throughput requirement 500/64kbps (DL/UL)• 20W BTS Tx power If DL only considered: -SINR requirement ≈ -6dB => RSRQ>-16.9dB, empty serving cell RSRQ>-17.7dB, fully loaded serving cell RSRP>-130dBm (1dB interference assumed)

If DL and UL considered -DL SINR requirement ≈ -3dB => RSRQ>-14.1dB, empty serving cell RSRQ>-15.5dB, fully loaded serving cell RSRP>-127dBm (1dB interference assumed)

Channel ModelAntenna Configuration 1Tx-2Rx 1Tx-2Rx

FDPS Type Round Robin -Users in Frequency Domain per TTI 2 10

FDPS Gain (dB) 0.00 -HARQ Gain (dB) 4.58 5.45

Minimum Required SINR (dB) -1.69 3.76Coding Rate Offset (dB) 0.20 0.34

Required SINR at Cell Edge (dB) -6.06 -1.35 Maximum SINR at Cell Edge (dB) -0.03 -

Neighbour Cell Load 50% 50%Method for Interference Margin User Defined User Defined

Interference Margin [Formula/Simulation] (dB) not selected not selectedInterference Margin [User Defined] (dB) 1.00 1.00

Number of Received Subcarriers (dB) 27.8 10.8Thermal Noise Density (dBm/Hz)

Subcarrier Bandwidth (kHz)Noise Power per Subcarrier (dBm)

Receiver Sensitivity (dBm) -103.45 -120.53Maximum Allowable Path Loss (dB)

(clutter not considered) 162.96 160.03

-17415

-132.17

Enhanced Pedestrian A 5 Hz


MIMO Type CQI_feedback_type(aperiodic) RSSI Ant0(LL1)Rx Freq[MHz] CQI_feedback_type(periodic) RSSI Ant1(LL1)Tx Freq[MHz] Codebook_Subset_Restriction TX Power(LL1)Downlink TP(Kbps) DL_BW Cell ID(Sync)Uplink TP(Kbps) CP_Type_DL SFNDL BLER eNB_ANT_Num PDSCH BLERUL BLER UE_Ant_Num RB Num(DL)SFN Cell_ID MCS Level0(DL)CINR0 UL_BW MCS Level1(DL)CINR1 CP_Type_UL PUSCH BLERCQI Metric0 PHICH_Group_Num RB Num(UL)CQI Metric1 PHICH_duration MCS Level(UL)RI Serving_Cell_ID PDCP info num(UL)Cell ID(Search) Serving_CINR PDCP info num(DL)CP type Serving_RSSI RRC stateRSRP(Ant0) Serving_RSRP EMM functional stateRSRQ(Ant0) Best_N1_Cell_ID EMM stateRSSI(Ant0) Best_N1_RSRP Phy DL TP(Mbps)RSRP(Ant1) Best_N1_RSSI Phy UL TP(Mbps)RSRQ(Ant1) Best_N2_Cell_ID Pa_IndexRSSI(Ant1) Best_N2_RSRP Pb_IndexTransmission_mode Best_N2_RSSI

Parameters are reported at one second interval.Parameters are reported at one second interval.

XCAL + Samsung reported parametersSamsung + XCAL, the most

used drive test combination at the moment in trials and FiVe.


Scanner measurement information PCTel Measuring both RS SINR and SCH SINR Wide band RSSI measurements and spectrum scanning supported

R&S Measuring only SCH SINR No support for wide band RSSI measurements and spectrum scanning Measuring only from Sync channel bandwidth (1.4MHz). Also RSRP and

RSRQ measured only from that bw.

JDSU E6474A Measuring only RS SINR Difficult post processing format (in Excel export) Wide band RSSI measurements and spectrum scanning supported


How can we calculate CQI from SINR?

Basically, we can calculate as CQI= SINR * 0.51 +5.3Basically, we can calculate as CQI= SINR * 0.51 +5.3

- Sample of MIMO Switching- Sample of MIMO Switching

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