1. Active Antennas Solutions 1st European Trial of AAU3902
Roman Łapszow, PhD
Active Antennas Solutions 1st European Trial of AAU3902
24th -26th September, Kraków

2. FOCUS ON (e)NodeB SOLUTIONS
Agenda
Currently available Active Antenna Systems features
Horizontal beamforming as a way to enhance capacity
Vertical beamforming AAU3902 field implementation
Future possible direction for innovations
Impact on Green aspects
FOCUS ON (e)NodeB SOLUTIONS

3. Active Antenna Systems (AAS) TODAY
VERTICAL Sectorization
VIRTUAL Sectorization
Sector split for inner and outer cell
High dependency on traffic distribution
One cell
Only PDSCH channels split to inner & outer beam
User specific tilt - UST
Horizontal Sectorization
4-virtual port antenna
Beams are generated by combinations of standard UE PMI Reports (8 beams)
UE: 4x2 CL MIMO
Multicolumn (wide antenna) is needed
Alternative for multisector
4-way Diversity – 4RxDiv
Secondary AAS Features
Uplink, Downlink, Frequency, RAT differentiated tilting
Failure recovery
PDSCH – Physical Downlink Shared Channel
PMI – Precoding Matrix Indicator
Gain in uplink only
Virtual receive patterns created either for V and H plane (dual column)
Active
Antenna Systems

4. Horizontal
Sectorisation

5. HORIZONTAL Sectorisation Principles
Selective transmission in optimized directions brings potential to increase performance efficiency
Phenomena of AZIMUTH DIRECTION and AZIMUTH SPREAD of received signal observed in testbed located in urban environment with 10 measuring points on street level and BS on rooftop (examples for UE1 and UE7 below)
source: analysis part of the AAS Innovation Project with Ericsson also more information available on
Directional Channel Characteristics in Elevation and Azimuth at an Urban Macrocell Base Station

6. network re-configuration
HORIZONTAL Sectorisation Limits
A SIMPLE CELL SPLIT IS NOT ENOUGH dB dB
network re-configuration
is needed
(azimuth rotating by 15o)
SINR for 6 sectors cluster BASED on 3-sector plan
SINR for 6 sectors after re-planning
azimuth spread in multipath environment limits the minimum horizontal HPBW
side lobe increase with increasing range of beam angle adjustment limits the range of adaptation
source: analysis part of the AAS Innovation Project with Huawei

7. Vertical
Sectorisation

8. VERTICAL Sectorisation (VS) Principles
Splitting cell in two: INNER & OUTER
spatial separation allows spectrum reuse and increase macro layer capacity
WHAT IS NEEDED TO SUPPORT VS:
Active antenna with beamforming in baseband
DOUBLE the cell number* => RF plan reconfiguration needed
Control upper side lobe suppression for inner cell beam
NON-UNIFORM TRAFFIC DISTRIBUTION
*) not the case of virtual sectorisation

9. VERTICAL Sectorisation Evaluation
+ INNER CELL THROUGHPUT GAIN
+ SECTOR CAPACITY GAIN ONLY if UE’s are located close to the site center
+ Antenna swap with the same azimuth direction
+ RF plan changes limited to tilt adjustment
+/- Transmitted power reduction to keep total power the same as legacy configuration => potential cell edge coverage degradation
- Limited flexibility of site configuration or reconfiguration

10. VS Trial Scenario 80049 80384 80223 Urban city and Rural Scenario
3 sites, 7 sectors
OPL/TMPL Ran-Sharing Scenario
3 carriers in each sector
Total power configuration before split 20W; after split 2x10W
Pilot Power Configuration 10%
VS active on 3 sectors, one sector per site

11. Site Configuration Before AAU Installation
BBU
AAU
ANT K
T-Mobile RRU
Orange RRU
Active Port
Passive Port
Orange RU
Before AAU Installation
After Existing Antenna SWAP to AAU3902
RX Div
diplexer
1 box saved, but 2 other diplexer needed

12. Coverage Change – due to antenna pattern change
VS - OFF
VS - ON
80384
outercell
80049
innercell
80049
80049
outercell
80384
innercell
80384
80223
innercell
80223
outercell
80223
coverage change observed on VS cell borders

13. VS Trial RESULTS – UL capacity
The same sector 3 carriers
Increase Traffic within same load
Load saving in same Traffic requirement
For uplink, VS can bring an average gain about 51%

14. VS Trial RESULTS – DL capacity
AAU_Baseline
VS_inner
VS_outer
Cell Average Throughput(kbps)
80049O2
80223O1
80384O3
number of Active HSDPA Users Assumed 5
Average User Throughput(kbps)
Gain for User Throughput
Baseline
1589%
5.72%
487%
3.85%
101%
63.99%
Significant throughput gains for inner cell are observed but only available for limited users located in inner cell.
For downlink, VS brought an average thp gain for outer cell about 24%.

15. possible negative gains
VS Trial RESULTS – analysis
Interference Increase/Capacity Gain Decrease
Inner User Number Ratio Increase/Capacity Gain Increase
Inner User
Number Ratio
30%
Scenario
Small ISD
Complex Multi-path
Environment
Obstruction
Large ISD
Open Area
No Obstruction
80049O1 97%
Ratio 50%
80223O1 83%
80384O3 68%
80049O1 5.72%
80223O % )
80384O %
Ratio 6%
Ratio 16%
Ratio 35%
Max Gain
(theoretically calculated)
Capacity Gain will decrease if the environment is more complex
If the inner user number ratio increase, the gain may achieve the max value.
DOWNLINK !
possible negative gains
*) for benchmark collected after tests
*) for benchmark collected after tests
*) for benchmark collected after tests

16. Future
Innovations

17. Principles of VVS+HB Virtual Vertical Sectorisation + Horizontal Beamforming
Antenna parameters:
HPBW H: 66,7°
HPBW V: 11,9°
range of vertical adjustment: od 0°do 15°
beam switching: ± 26,6° (53,2°)
Innovation
sub-beam 1
sub-beam 3
sub-beam 2
sub-beam 4
Number of ports are assigned according to 3GPP TS standard
No /14

18. Results for VVS+HB DL (VVS) UL (VVS)
Reference cell throughput per sector in typical 3-sector passive antenna configuration
Estimated cell throughput per sector based on simulations (full buffer) for
VVS-type only
UL (VVS)
DL (VVS)
Average cell throughput gain estimations are in range 40 to 70% (both UL and DL)
Antenna does not require site construction changes
Reduced number of antennas in comparison to multisector configuration

19. “Green”
Energy
Savings

20. AAS Impact on Power Consumption
Observations and thesis after trial in Orange Poland with AAU3902
AAS VS feature allows reduction of the maximum emitted power in a single cell from 20W to 10W.
Due to improved radio condition for inner cell users the total power emission should be reduced due to power control mechanism (not measured).
Reduced interference being consequence of outer cell power reduction should allow reduction of required emitted power in DL that with VS feature is limited to 10W.
Higher throughput capacity in UL allows limit time of the transmission by UE and reduce battery consumption (not measured in the trial).

21. Summary & Conclusions
AAS VS features provides gains: UE throughput, capacity gains and they are relevant to traffic distribution and sensitive to the implementation scenario.
Self Optimizing Network related features need to be implemented as integral part of E2E VS solution to allow dynamic activation of the feature (to avoid negative gains).
First AAS trials proves ability for decrease energy consumption by limiting radiated power in individually created beams.

22. Thank you

23. Gain Definitions
UL_1:
UL_2:
DL: