Mpcs la
lte ho parameters trial
Overview
• A study on the effect of handover parameters on the network performance
will be done in a trial cluster (part of Cerritos)
• The parameter change to be implemented as an iterative process with each
drive and the results to be compared to analyze the effect of the
parameters
• Following parameters to be changed
A3offset;
hysteresisA3;
filtercoefficientEutranRsrp;
sMeasure;
timetotriggerA3
Review: LTE HO
• Evaluates if one or more intra frequency cell is better than current serving
cell
• UE receives measurement configuration in RRC Connection Reconfiguration
• No measurement list sent to UE (UE search for all 504 physical cell id and
reports the cell(s) fulfilling the event criteria).
• UE Event Trigger controlled by:
– Filtering (How much averaging is done before event evaluation)
– Offset (How much better in dB)
– Time to trigger (For how long)
Main Trigger Parameters
•
sMeasure = 0 { -140..-44, 0 } [dBm]
Controlling if the UE is required to perform measurements.
Disabled if set to “0” (used only RSRP is the trigger)
•
a3offset = 30 { -150..150 } [0.1 dB]
Offset value for EventA3, added to serving cell
•
hysteresisA3 = 10 { 0..150 } [0.1 dB]
Hysteresis value for eventA3, added to neighbor cell
•
timeToTriggerA3 = 40 { 0, 40, 64, 80, 100, 128, 160, 256, 320, 480, 512,
640, 1024, 1280, 2560, 5120 } [ms]
Time after Event A3 is fulfilled when UE starts to send Measurement reports
•
triggerQuantityA3 = RSRP [RSRP,RSRQ]
The quantity that triggers the event
•
cellIndividualOffsetEUtran
Offset value specific to a neighbor relation
Handover Filtering
• To avoid that the measurement reporting is triggered by fast fading, the
measurement configuration contains filter coefficient for the UE to use
• filterCoefficientEUtraRsrp = 9{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19 }
Filter coefficient for RSRP measurements
• filterCoefficientEUtraRsrq = 11{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19 }
Filter coefficient for RSRQ measurements
Event A3: A neighbour cell(b) becomes offset
better than serving cell(a)
Drive Info
Drive Details
Test
Baseline
Offset1
Offset2
Offset3
Hyst1
Hyst2
Hyst3
Hyst4
TTT1
TTT2
TTT3
FC1
FC2
FC3
FC4
SM1
SM2
BL2
BL3
Hyst0
Hyst5
TTT0
SM3
Baseline
TTT4
Parameter
a3offset=10
a3offset=20
a3offset=30
hysteresisA3=30
hysteresisA3=40
hysteresisA3=60
hysteresisA3=70
timeToTriggerA3=80
timeToTriggerA3=160
timeToTriggerA3=320
filterCoefficientEUtraRsrp=7
filterCoefficientEUtraRsrp=5
filterCoefficientEUtraRsrp=13
filterCoefficientEUtraRsrp=11
sMeasure=-70
sMeasure=-80
Baseline2
Baseline3
hysteresisA3=20
hysteresisA3=80
timeToTriggerA3=0
sMeasure=-90
Baseline
timeToTrigger=640
Date Started
12/17/2010
12/23/2010
12/27/2010
12/28/2010
12/29/2010
12/30/2010
12/30/2010
01/03/2011
01/05/2011
01/05/2011
01/12/2011
01/12/2011
01/13/2011
01/13/2011
01/14/2011
01/15/2011
01/17/2011
01/18/2011
01/19/2011
01/20/2011
01/21/2011
01/25/2011
01/25/2011
01/25/2011
01/26/2011
Time Started
21:15:00
21:00:00
20:30:00
23:15:00
20:00:00
20:30:00
22:30:00
20:15:00
20:30:00
22:45:00
20:00:00
23:00:00
20:00:00
22:45:00
20:15:00
19:45:00
20:30:00
20:00:00
20:30:00
20:15:00
20:45:00
00:30:00
19:00:00
21:30:00
01:15:00
Date Finished
12/13/2010
12/23/2010
12/27/2010
12/28/2010
12/29/2010
12/30/2010
12/31/2010
01/03/2010
01/05/2011
01/06/2011
01/12/2011
02/13/2011
01/13/2011
01/14/2011
01/14/2011
01/15/2011
01/17/2011
01/18/2011
01/19/2011
01/20/2011
01/21/2011
01/25/2011
01/25/2011
01/26/2011
01/26/2011
Time Finished
00:30:00
23:15:00
23:00:00
01:45:00
22:15:00
22:30:00
01:30:00
22:15:00
22:45:00
00:45:00
22:30:00
01:00:00
22:30:00
00:45:00
22:30:00
22:15:00
22:45:00
22:30:00
23:00:00
23:15:00
23:30:00
02:45:00
21:15:00
01:00:00
03:00:00
Trial Cluster – Drive Route
Baseline Test Cases
MO
Parameter
Baseline
BL2
BL3
UeMeasControl
sMeasure
0
0
-80
UeMeasControl
filterCoefficientEUtraRsrp
9
5
4
ReportConfigEUtraBestCell
hysteresisA3
50
30
0
ReportConfigEUtraBestCell
timeToTriggerA3
40
40
480
ReportConfigEUtraBestCell
a3offset
0
10
40
Cell Availability
Retainability (Session Failure Rate)
Integrity DL Throughput Mean (kbps)
Integrity DL Throughput Max (kbps)
Mobility (Handover Success Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency Handover Failed events
EUTRAN Intra-frequency Handover (success)
events
Baseline
100%
0%
2636.85
3664.32
100%
14
14
0
Baseline 2
100%
26%
2482.42
3600.96
100%
19
14
0
Baseline 3
100%
0%
2511.49
3738.24
100%
14
14
0
192
322
161
Baseline Test Cases (contd)
Handover Measurement Info (Source-to-Target)
Baseline
Average Delta RSRP (dBm)
Average Delta RSRQ (dB)
8
7
6
5
6.7
5.5
5.3
4.0
4
3
2
2.8
1.6
1
0
Baseline
•
Baseline 2
Baseline 3
Baseline2 drive demonstrated the highest number of handovers and the smallest
delta in RSRP/RSRQ.
Baseline Test Cases (contd)
PRE-HANDOVER SINR CDF (% )
Baseline
Baseline
Baseline2
Baseline3
100
90
80
Percentage
70
60
50
40
30
20
10
0
1
3
5
7
9
11
13
15
17
19
21
23
25
27
SINR
•
Baseline drive demonstrated the best SINR performance.
29
31
33
35
37
39
41
A3offset Test Cases
MO
Parameter
Baseline
Offset1
Offset2
Offset3
Offset4
UeMeasControl
sMeasure
0
0
0
0
0
UeMeasControl
filterCoefficientEUtraRsrp
9
9
9
9
9
ReportConfigEUtraBestCell
hysteresisA3
50
50
50
50
50
ReportConfigEUtraBestCell
timeToTriggerA3
40
40
40
40
40
ReportConfigEUtraBestCell
a3offset
0
10
20
30
40
Cell Availability
Retainability (Session Failure Rate)
Integrity DL Throughput Mean (kbps)
Integrity DL Throughput Max (kbps)
Mobility (Handover Success Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency Handover
Failed events
EUTRAN Intra-frequency Handover
(success) events
Baseline (0)
100%
0%
2636.85
3664.32
100%
14
14
a3offset=10
100%
0%
2365
3632
100%
13
13
a3offset=20
100%
0%
2509.72
3696
99.23%
13
13
a3offset=30
100%
0%
2415.835
3674.88
100%
14
13
a3offset=40
100%
0%
2564.95
3653.76
100%
18
17
0
0
1
0
0
192
161
129
118
99
A3offset Test Cases (contd)
Handover Measurement Info (Source-to-Target)
a3Offset
Average Delta RSRP (dBm)
Average Delta RSRQ (dB)
10
9.0
8.2
8
6
4
7.4
6.6
5.5
4.2
2.8
4.9
5.2
a3Offset=30
a3Offset=40
3.4
2
0
Baseline (0)
•
•
a3Offset=10
a3Offset=20
There was a clear decrease in the number of handovers and an increase in the
RSRP/RSRQ delta as went from a3offset=0 to a3offset=40.
This is expected as the sum of hysteresisA3 and a3offset increases.
Notice, as expected, Delta RSRP ~ hysteresisA3+a3offset.
A3offset Test Cases (contd)
PRE-HANDOVER SINR CDF (% )
a3Offset
Baseline (0)
a3Offset=10
a3Offset=20
a3Offset=30
a3Offset=40
100
90
80
Percentage
70
60
50
40
30
20
10
0
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
SINR
•
Baseline (smallest offset) demonstrated the best SINR performance.
35
37
39
41
HysteresisA3 Test Cases
MO
Parameter
Hyst0
Hyst1
Hyst2
Baseline
Hyst3
Hyst4
Hyst5
UeMeasControl
sMeasure
0
0
0
0
0
0
0
UeMeasControl
filterCoefficientEUtraRsrp
9
9
9
9
9
9
9
ReportConfigEUtraBestCell
hysteresisA3
20
30
40
50
60
70
80
ReportConfigEUtraBestCell
timeToTriggerA3
40
40
40
40
40
40
40
ReportConfigEUtraBestCell
a3offset
0
0
0
0
0
0
0
Cell Availability
Retainability (Session Failure
Rate)
Integrity DL Throughput Mean
(kbps)
Integrity DL Throughput Max
(kbps)
Mobility (Handover Success
Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency
Handover Failed events
EUTRAN Intra-frequency
Handover (success) events
hysteresisA3=20
hysteresisA3=30
hysteresisA3=40
Baseline (50)
hysteresisA3=60
hysteresisA3=70
hysteresisA3=80
100%
100%
100%
100%
100%
100%
100%
19%
0%
0%
0%
0%
0%
0%
2545.26
2380.99
2418.08
2636.85
2464.73
2275.54
2548.9
3706.56
3590.4
3664.32
3664.32
3442.56
3643.2
3632.64
100%
16
13
100%
13
13
100%
14
14
100%
14
14
100%
13
13
100%
12
12
100%
14
14
0
1
0
0
0
0
0
417
337
224
192
131
140
121
HysteresisA3 Test Cases
(contd)
Handover Measurement Info (Source-to-Target)
hysteresis
Average Delta RSRP (dBm)
Average Delta RSRQ (dB)
9
8.2
7.5
8
6.6
7
5.5
6
4.9
4.8
5
4.2
3.9
4
3.5
3.0
2.8
3
2.2
1.6
2
1.0
1
0
hysteresisA3=20
•
•
hysteresisA3=30
hysteresisA3=40
Baseline (50)
hysteresisA3=60
hysteresisA3=70
hysteresisA3=80
There was a clear decrease in the number of handovers and an increase in the
RSRP/RSRQ delta as went from hysteresisA3=20 to hysteresisA3=80.
This is expected as the sum of hysteresisA3 and a3offset increases.
Notice, as expected, Delta RSRP ~ hysteresisA3+a3offset.
HysteresisA3 Test Cases
(contd)
PRE-HANDOVER SINR CDF (% )
Hysteresis
hysteresisA3=20
hysteresisA3=60
hysteresisA3=30
hysteresisA3=70
hysteresisA3=40
hysteresisA3=80
Baseline (50)
100
90
80
Percentage
70
60
50
40
30
20
10
0
-10
-8
-6
-4
-2
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
SINR
•
hysteresisA3=20 (smallest hysteresis) demonstrated the best SINR performance.
TimeToTriggerA3 Test Cases
MO
Parameter
TTT0
Baseline
TTT1
TTT2
TTT3
TTT4
UeMeasControl
sMeasure
0
0
0
0
0
0
UeMeasControl
filterCoefficientEUtraRsrp
9
9
9
9
9
9
ReportConfigEUtraBestCell
hysteresisA3
50
50
50
50
50
50
ReportConfigEUtraBestCell
timeToTriggerA3
0
40
80
160
320
640
ReportConfigEUtraBestCell
a3offset
0
0
0
0
0
0
Cell Availability
Retainability (Session Failure
Rate)
Integrity DL Throughput
Mean (kbps)
Integrity DL Throughput Max
(kbps)
Mobility (Handover Success
Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency
Handover Failed events
EUTRAN Intra-frequency
Handover (success) events
timeToTriggerA3= 0
Baseline (40)
timeToTriggerA3= 80
timeToTriggerA3= 160
timeToTriggerA3= 320
timeToTriggerA3= 640
100%
100%
100%
100%
100%
100%
0%
0%
0%
0%
0%
0%
2618.28
2636.85
2487.26
2461.05
2461.72
2654.53
3633.24
3664.32
3600.96
3696
3653.22
3674.88
100%
13
13
100%
14
14
100%
13
13
100%
13
13
100%
13
13
100%
13
13
0
0
0
0
0
0
187
192
197
186
171
120
TimeToTriggerA3 Test Cases
(contd)
Handover Measurement Info (Source-to-Target)
timeToTriggerA3
Average Delta RSRP (dBm)
8
7
6
5
4
3
2
2.7
2.8
3.2
6.7
6.4
6.2
5.9
5.5
5.3
Average Delta RSRQ (dB)
3.3
4.3
3.9
1
0
timeToTriggerA3=0
•
Baseline (40)
timeToTriggerA3=80
timeToTriggerA3=160
timeToTriggerA3=320
timeToTriggerA3=640
Number of handovers decreased and RSRP/RSRQ delta increased with the
increasing timeToTrigger. This is as expected.
TimeToTriggerA3 Test Cases (contd)
PRE-HANDOVER SINR CDF (% )
timeToTriggerA3
timeToTriggerA3=0
timeToTriggerA3=160
Baseline (40)
timeToTriggerA3=320
timeToTriggerA3=80
timeToTriggerA3=640
100
90
80
Percentage
70
60
50
40
30
20
10
0
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
39
SINR
•
timeToTriggerA3=0 and Baseline(40) demonstrated the best SINR performance.
41
FilterCoefficientEutraRSRP Test Cases
MO
Parameter
FC0
FC2
FC1
Baseline
FC4
FC3
UeMeasControl
sMeasure
0
0
0
0
0
0
UeMeasControl
filterCoefficientEUtraRsrp
3
5
7
9
11
13
ReportConfigEUtraBestCell
hysteresisA3
50
50
50
50
50
50
ReportConfigEUtraBestCell
timeToTriggerA3
40
40
40
40
40
40
ReportConfigEUtraBestCell
a3offset
0
0
0
0
0
0
Cell Availability
Retainability (Session Failure Rate)
Integrity DL Throughput Mean (kbps)
Integrity DL Throughput Max (kbps)
Mobility (Handover Success Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency Handover
Failed events
EUTRAN Intra-frequency Handover
(success) events
filterCoefficient
EUtraRsrp=3
100%
0%
2661.5
3706.56
100%
13
13
filterCoefficient
EUtraRsrp=5
100%
0%
2549.69
3600.96
100%
13
13
filterCoefficient
EUtraRsrp=7
100%
0%
2423.83
3590.4
100%
13
13
Baseline (9)
100%
0%
2636.85
3664.32
100%
14
14
filterCoefficient
EUtraRsrp=11
100%
0%
2553.79
3706.56
99.38%
13
13
filterCoefficient
EUtraRsrp=13
100%
0%
2540.09
3759.36
100.00%
13
13
0
0
0
0
1
0
269
262
214
192
161
141
FilterCoefficientEutraRSRP Test Cases (contd)
Handover Measurement Info (Source-to-Target)
filterCoefficientEUtraRsrp
Average Delta RSRP (dBm)
7
6.0
6.0
5.8
6
Average Delta RSRQ (dB)
5.5
5.5
5
5.4
3.8
4
3
2.0
2.2
2.6
4.4
2.8
2
1
0
filterCoefficientEUtraRsrp=3 filterCoefficientEUtraRsrp=5 filterCoefficientEUtraRsrp=7
•
•
Baseline (9)
filterCoefficientEUtraRsrp=11 filterCoefficientEUtraRsrp=13
Number of handovers decreased and RSRP/RSRQ delta increased with the
increasing filterCoefficientEUtraRsrp.
This is as expected as the number of measurement samples analyzed for each
handover increases.
FilterCoefficientEutraRSRP Test Cases (contd)
PRE-HANDOVER SINR CDF (% )
filterCoefficientEUtraRsrp
filterCoefficientEUtraRsrp=3
Baseline(9)
filterCoefficientEUtraRsrp=5
filterCoefficientEUtraRsrp=11
filterCoefficientEUtraRsrp=7
filterCoefficientEUtraRsrp=13
100
90
80
Percentage
70
60
50
40
30
20
10
0
1
3
5
7
9
11
13
15
17
19
21
SINR
•
Baseline gave the best SINR performance.
23
25
27
29
31
33
35
37
39
41
sMeasure test cases
MO
Parameter
Baseline
SM1
SM2
SM3
UeMeasControl
sMeasure
0
-70
-80
-90
UeMeasControl
filterCoefficientEUtraRsrp
9
9
9
9
ReportConfigEUtraBestCell
hysteresisA3
50
50
50
50
ReportConfigEUtraBestCell
timeToTriggerA3
40
40
40
40
ReportConfigEUtraBestCell
a3offset
0
0
0
0
Cell Availability
Retainability (Session Failure Rate)
Integrity DL Throughput Mean (kbps)
Integrity DL Throughput Max (kbps)
Mobility (Handover Success Rate)
FTP DL session starts
FTP DL session ends
EUTRAN Intra-frequency Handover Failed events
EUTRAN Intra-frequency Handover (success) events
Baseline (0)
100%
0%
2636.85
3664.32
100%
14
14
0
192
sMeasure=-70
100%
0%
2251.63
3812.16
100%
14
14
0
188
sMeasure=-80
100%
0%
2496.11
3643.2
100%
13
13
0
204
sMeasure=-90
100%
0%
2603.72
3590.4
99.5%
13
13
1
193
sMeasure test cases (contd)
Handover Measurem ent Info (Source-to-Target)
sMeasure
Average Delta RSRP (dBm)
7
6
5.9
5.7
5.5
Average Delta RSRQ (dB)
5.8
5
4
3
2.8
3.3
3.2
3.1
sMeasure=-70
sMeasure=-80
sMeasure=-90
2
1
0
Baseline (0)
•
No apparent trend was observed between these drives.
sMeasure test cases (contd)
PRE-HANDOVER SINR CDF (% )
sMeasure
Baseline (0)
sMeasure=-70
sMeasure=-80
sMeasure=-90
100
90
80
Percentage
70
60
50
40
30
20
10
0
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
39
41
SINR
•
The effect of sMeasure parameter on the network is inconclusive in regards to the
performed drives.
Summary
• Tested parameters for the most part resulted in the expected behavior:
– Number of Handover events.
– RSRP/RSRQ delta upon Handover.
– Pre-handover SINR performance.
• Part of the unexpected behavior can be attributed to the variation in drive
test setup between some of the drives.
• The effect of sMeasure parameter on the network is inconclusive at this
point. It will be further analyzed during the testing on DAS nodes.
• Current Baseline is pretty suitable to the network at this early stage of
operation. It is recommended that optimization, when performed, be
performed on a case by case basis.
THANK YOU