Energy Performance of Heterogeneous LTE Networks

Transcription

1 Energy Performance of Heterogeneous LTE Networks Henrik Forssell, Gunther Auer, Daniel Dianat Ericsson AB Stockholm, Sweden Third ETSI Workshop on ICT Energy Efficiency and Environmental Sustainability 3-5 June 2015 Sophia Antipolis

2 Outline Problem formulation EARTH base station power model Scenario Simulation results Conclusion HetNet Energy Efficiency Public Ericsson AB Page 2

3 Het Net Scenario Consumed Power Macro Macro Indoor Small Cell Small Cell Load HetNet Energy Efficiency Public Ericsson AB Page 3

4 Problem Formulation How does het net deployment affect the energy performance? Elaborate trade-off between small cell transmit power and node density? What is the potential for energy savings using sleep modes? HetNet Energy Efficiency Public Ericsson AB Page 4

5 Energy Performance Assessment Methodology Post Processing Power Consumption Models Energy Saving techniques HetNet Energy Efficiency Public Ericsson AB Page 5

6 EARTH Base Station Power Model Load dependent part HetNet Energy Efficiency Public Ericsson AB Page 6 Fixed constant part 0 Resource utilization [%] 100

7 Discontinuous Transmission Power saving Resource utilization [%] On Sleep Time Radio-frame 10ms HetNet Energy Efficiency Public Ericsson AB Page 7

8 Discontinuous Transmission Micro DTX MBSFN DTX Lean Carrier DTX CR S Radio-frame 10ms MBSFN sub-frames 41% 59% on DTX 59% 41% on MBSFN 100 % On Sleep MBSFN: Multi-cast and Broadcast Single Frequency Network HetNet Energy Efficiency Public Ericsson AB Page 8

9 Small Cell Sleep Modes Macro Traffic load: High HetNet Energy Efficiency Public Ericsson AB Page 9

10 Small Cell Sleep Modes Sleep Sleep Macro Traffic load: Low HetNet Energy Efficiency Public Ericsson AB Page 10

11 Simulation Scenario HetNet Energy Efficiency Public Ericsson AB Page 11

12 Simulation Scenario Asian Scenario Dense urban (inspired by Tokyo and Seoul) Macro deployment (3-sector sites) Surrounding macro ISD = 400m Center macro ISD = 200m 10 largest buildings Small cell deployment HetNet Energy Efficiency Public Ericsson AB Page 12

13 Small Cell Deployment Deployment Type Sparse Coverage area per node 1000 m 2 Number of nodes x HetNet Energy Efficiency Public Ericsson AB Page 13

14 Small Cell Deployment Deployment Type Dense Coverage area per node 600 m 2 Number of nodes x HetNet Energy Efficiency Public Ericsson AB Page 14

15 Result Evaluation Center area polygon Area: 1 km 2 Contains high-rise center area HetNet Energy Efficiency Public Ericsson AB Page 15

16 Simulation Results Deployment Transmit power Capacity Sparse Pico 100, 200 and 500mW Mbps Total power consumption 10 th percentile DL user throughput + Small Cell Increase 2x Capacity 10 Mbps - Macro Offload HetNet Energy Efficiency Public Ericsson AB Page 16

17 Simulation Results Deployment Transmit power Capacity Sparse Pico 100, 200 and 500mW Mbps 2x Peak Throughput HetNet Energy Efficiency Public Ericsson AB Page 17

18 DTX Energy Savings HetNet Energy Efficiency Public Ericsson AB Page 18

19 Sleep Mode Energy Savings HetNet Energy Efficiency Public Ericsson AB Page 19

20 Sleep Mode Energy Savings HetNet Energy Efficiency Public Ericsson AB Page 20

21 Conclusion The deployment of small cells increases the performance of the network, but without energy saving techniques the power consumption is up to 3x higher than that of the macro reference. With energy saving techniques such as DTX and small cell sleep modes, the energy consumption of the HetNets can be reduced. From an energy performance perspective, dense low power pico deployment vs a sparse high power pico deployment are equally efficient. Micro DAS however, have shown to be a deployment of poor energy efficiency due to high feeder losses in the cables HetNet Energy Efficiency Public Ericsson AB Page 21

22 Conclusion The results also show that the total daily energy consumption of the HetNets can be reduced by 10-20% with DTX. Introducing longer sleep periods also show potential for energy savings. The result shows that with a sparse pico deployment, the power consumption at low traffic loads can be reduced by 33%. HetNet Energy Efficiency Public Ericsson AB Page 22

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