Self%OpmisaonofVer(calSectorisaonina...
Transcript of Self%OpmisaonofVer(calSectorisaonina...
Self-‐Op(misa(on of Ver(cal Sectorisa(on in a Realis(c LTE Network
EuCNC 2015, June 30, 2015, Issy les Moulineaux
Konstantinos Trichias, Remco Litjens (TNO) Abdoulaye Tall, Zwi Altman (Orange Labs)
Pradeepa Ramachandra (Ericsson Research)
§ Introduction § Vertical sectorization (VS) § SON for vertical sectorization § Futur evolutions of VS § Conclusions
Outline
2 SEMAFOUR
§ SON – Self Organizing Network
ü Self-configuration (simplify deployment) ü Self-optimization (enhance performance) ü Self-healing (manage faults)
§ SON deployment ü Centralized SON (C-‐SON) ü Distributed SON (D-‐SON)
Introduction (1/3)
3 SEMAFOUR
MROMLB
ICICES
RACH OptCCOCOC
ANR
LTE-AdvancedRelease >=10
LTERelease 8,9
Release 12
2013
§ Vertical Sectorization (VS) ü Active Antenna System (AAS) technology: RF components integrated in the antenna
§ UE beam stearing § Separate Tx-Rx tilting § Separate carrier tilting § …
ü VS: the antenna can support two beams: two sectors with distinct cell ID ü A capacity solution: network densification
Introduction (2/3)
4 SEMAFOUR
§ Challenges for VS technology / deployment addressed in the SEMAFOUR project
1. Type of deployment: network-wide or per cell 2. What are the conditions to (de)activate VS to ensure performance gains as a
function of ü Traffic distribution ü Time reactivity ü Propagation, in terms of Vertical Angular Spread (VAS)
3. What power allocation between inner and outer cells should be performed? 4. Design simple SON algorithms for
ü VS (de)activation ü Power allocation
5. What are possible evolutions of VS ü Virtual Sectorization (ViS)
Introduction (3/3)
5 SEMAFOUR
§ LTE network, 1800 MHz, 20 MHz bandwidth § Environment: Urban and suburban § Propagation: ray tracing § Calculation zone: 5x7 km2, 63 sites § Performance evaluation zone: 3x5 km2, 36 sites § Traffic: Elastic
Hannover scenario
6 SEMAFOUR
Performance results
8 SEMAFOUR
§ Gain for network wide deployment
§ VS at cell 52 (most loaded cell) only
Impact of propagation on performance
9 SEMAFOUR
Vertical Angular Spread
(degrees)
Average - Average user
throughput gain from VS
Average - 10th percentile user
throughput gain from VS
Average - Ratio Inner Sector /
Total size
7 < AS < 10 50.91% 132.45% 26.14% 4 < AS < 7 26.27% 73.98% 12.28%
AS < 4 10.96% 40.03% 5.69%
§ Angular spread
§ Analytical formulation (K. Trichias et al. “Performance evaluation and SON aspects of Vertical
Sectorisation in a realistic LTE network environment”, IWSON-IV, 2014)
§ The decision boundary is calibrated using measurements / simulations
– When VS is off, estimation of inner and outer loads are required
(De)Activation VS SON
10 SEMAFOUR
ρinner
ρ outer
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Decision boundary for VS OFFDecision boundary for VS ON
VS ON
VS OFF
§ Allocated power depends on both – The vertical sectorized cell – Its neigbboring cells
§ SON algorithm:
– Neighboring mobiles are considered if their path-loss to the serving BS is
smaller than 115 dB
Power Allocation SON
12 SEMAFOUR
§ Using VS (de)activation & Power Allocation SON
Results: capacity gain
13 SEMAFOUR
Gain (high load) No VS Full VSAverage 45% 9,50%10th percentile 140% 26%
§ Generate a beam – virtual sector anywhere in the cell § Technological challenges
– Antenna optimization with high gain and low sidelobes – SON for resource allocation / interference management – Adapt beam location to traffic localization
Futur evolutions of VS: Virtual sectorization (ViS)
14 SEMAFOUR
z
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“Virtual-secorization: design and self-optimization”, in IWSON-V 2015