MEASUREMENTS AND
ANALYSIS
42
word 0 in MIMO scenario. Similar analysis can be drawn for codeword 1. Kumpuvaara
site has been taken primarily for analyzing purpose because of the reason that the route
falls directly under the coverage of cell 111 unlike Singerjärvi site which has cell cover-
age mostly not falling under the measurement route.
Table 7.3: Link modulation statistics for Kumpuvaara site
PCI Maximum RSRP Minimum RSRP
Codeword 0
Codeword 1
Count
110
-82.8
-135 QPSK
323
110
-82.8
-135 QPSK
QPSK
238
110
-82.8
-135 QPSK
16QAM
189
110
-86.1
-101.4 QPSK
64QAM
31
110
-82.8
-135 16QAM
286
110
-82.8
-102.9 16QAM
QPSK
188
110
-82.8
-102.9 16QAM
16QAM
233
110
-83.2
-101.4 16QAM
64QAM
67
110
-82.8
-111.6 64QAM
100
110
-83.7
-102.6 64QAM
QPSK
29
110
-82.8
-102.6 64QAM
16QAM
67
110
-82.8
-101.4 64QAM
64QAM
72
111
-70.1
-117.5 QPSK
1074
111
-68.8
-115.3 QPSK
QPSK
552
111
-70.1
-111.4 QPSK
16QAM
305
111
-71.7
-115.3 QPSK
64QAM
82
111
-70.1
-117.5 16QAM
866
111
-70.1
-112.8 16QAM
QPSK
355
111
-68.8
-111.4 16QAM
16QAM
470
111
-70.1
-112.4 16QAM
64QAM
275
111
-70.1
-114.6 64QAM
359
111
-71.7
-115.3 64QAM
QPSK
112
111
-70.1
-115.3 64QAM
16QAM
321
111
-68.8
-115.3 64QAM
64QAM
344
112
-66.9
-106 QPSK
288
112
-66.9
-106 QPSK
QPSK
374
112
-71.1
-104.1 QPSK
16QAM
194
112
-72.4
-102.8 QPSK
64QAM
68
112
-66.9
-106 16QAM
297
112
-67
-106 16QAM
QPSK
175
112
-66.9
-104.1 16QAM
16QAM
365
112
-66.9
-103.2 16QAM
64QAM
239
112
-66.9
-104.1 64QAM
261
112
-71.6
-104.1 64QAM
QPSK
74
112
-66.9
-103.2 64QAM
16QAM
268
112
-66.9
-103.2 64QAM
64QAM
309
Table 7.3 shows the detailed statistics on the distribution of different modulation
schemes partitioned by the serving PCI of the Kumpuvaara site. Maximum and mini-
mum RSRP shows the corresponding floor and ceil of the RSRP distribution for the
MEASUREMENTS AND ANALYSIS
43
0
500
1000
1500
2000
2500
3000
3500
4000
101
102
103
N
umb
er o
f S
amp
le
s
Physical Cell Identity (PCI)
Singerjärvi
Modulation Statistics
QPSK
16 QAM
64 QAM
0
500
1000
1500
2000
2500
110
111
112
N
umb
er o
f S
amp
le
s
Physical Cell Identity (PCI)
Kumpuvaara
Modulation Statistics
QPSK
16QAM
64QAM
particular PCI with the particular combination of modulation in two MIMO layers. The
null or blank values in modulation scheme of codeword 1 shows that the Physical
Downlink Shared Channel (PDSCH) rank is 1 in that case. Finally the count gives the
count of rows for the particular selection combination.
Figure 7.5: Kumpuvaara and Singerjärvi modulation schemes for different PCIs
Figure 7.5 shows distribution of modulation schemes over the coverage of different
cells for both sites. In case of Kumpuvaara, the DL path has been associated with QPSK
for 37.7% of all time and 38.7% with 16-QAM. For 23.5% of time, the DL modulation
was 64-QAM. In case of Singerjärvi, the modulation was QPSK for 47.5% of time, 16-
QAM for 30.9% of time and 21.4% for 64-QAM.
Being associated with QPSK would indicate worse CQI as explained earlier in Section
5.1. For the Kumpuvaara site, it indicates that the site had a poor coverage in terms of
link modulation for 37% of time and best coverage for 23.5%. For the Singerjärvi site,
the site had poorer coverage for 47.5% of time and best coverage for 21.4% of time.
Recollecting the facts from Figure 7.4, the worst RSRP observed for Kumpuvaara site
with QPSK as the DL modulation scheme is -135 dBm and the best RSRP is at -66.9
dBm. Similarly, the worst RSRP observed for Kumpuvaara site with 64-QAM as the
DL modulation is -111.6 dBm and the best RSRP being -66.9 dBm.
Link adaptation however may not give a clear picture of coverage area but indicates the
channel quality in the coverage area. A point in the measurement route near to the site
might have poorer CQI compared to a point farther to the site all depending upon the
radio environment.
MEASUREMENTS AND ANALYSIS
44
7.1.3.
RSRP coverage analysis
7.1.3.1
PCI coverage
Figure 7.6: PCI coverage for Kumpuvaara site
Figure 7.6 shows the distribution of PCIs for the Kumpuvaara site in the measurement
route. The measurement points have been filtered to display only the points where the
Kumpuvaara site acts as the active/serving cell. PCIs associated with the two test sites
are given in Table 7.1.
Figure 7.7: RSRP levels for different PCIs along the measurement route for Kumpuvaara site
MEASUREMENTS AND ANALYSIS
45
m
Figure 7.7 shows the interpretation of Figure 7.6 on time scale. The eNodeBs have been
marked and the PCIs have been color coded. The measurement has been taken from the
cell edge towards the cell center (made clear by the rising trend of the serving cell
RSRP level). Red, green and blue lines are associated with PCIs 110,111 and 112 re-
spectively. The figure also clearly indicates the handovers between the cells; the transi-
tions made clear by change in PCI as well as with the handover events marked. The
blank spots in the timeline are the coverage area of Singerjärvi site. The antenna beam
pattern for the site are shown matching to the actual antenna orientation.
Figure 7.6 shows that the measurement points are served mostly by cell 111. The meas-
urement route itself mostly falls under the coverage area of cell 111. The cell edge can
be described as the point where the UE last remains attached with the current serving
cell. Cell 111 is last traced till the distance of 17.3 km from Kumpuvaara site. The cell
edge value for the serving cell 111 is -106.2 dBm. Figure 7.7 shows that the there is a
gap in the coverage indicating that Singerjärvi cell is intersecting Kumpuvaara cell.
The coverage of a cell is physically defined by the antenna orientation (the angle at
which the cell antenna is fixed on the mast) and the transmit power. Other determining
factors are the antenna beamwidth, side lobe levels etc. which are again associated with
the transmitting antenna. As seen from Figure 7.6, the measurement route is mostly
covered by cell 111. The measurement also verifies that 57% of the measurement events
have been associated with cell 111, 20 % with cell 110 and 22% with cell 112.
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