In addition to validation in our San Diego campus, Qualcomm has also collaborated with various operators and small cells vendors to test the semi-planned or unplanned small cell deployment model and UltraSON features in different trials. Common deployment scenarios such as residential, enterprise and outdoor metros were covered in these trials.
The hyperdense deployment was shown to achieve a 44x increase in capacity over traditional deployment. In addition, significant reduction in signaling and improvement in user experience were observed in each trial as a result of UltraSON.
Indoor Residential Small Cells
Residential neighborhoods in suburban and urban areas were chosen as the venues for testing. In each case, small cells were deployed in 2-story apartment buildings or homes.
This trial showed the following results:
- Handover frequency dropped by up to 90%
- Cell-edge user throughput increased by over 40%
- User median throughput increased by 46%
- Reestablishment success rate after handover increased from 44% to 92%
Enterprise Small Cell Network in Shopping Mall
Small cells were deployed in a 3-story shopping mall. These small cells provided coverage over the entire mall and different tests were carried out on the second level.
When 6 UEs were dropped in the mall to create load on all small cells, the users at the cell edge benefited from the Resource Management (RM) feature in UltraSON and saw an average increase in cell-edge data rate by 60%.
In another test case, a quasi-stationary UE at handover boundary between 2 small cells experienced a 76% reduction in handover frequency due to the Frequent Handover Mitigation (FHM) feature.
Densest LTE Small Cell Network at NASCAR Phoenix
To demonstrate the viability of the hyper-dense small cells deployment model, Qualcomm deployed a small cell network in the garage area of the Phoenix International Raceway. The network consisted of 31 small cells, with inter-site distance as low as 7m, creating an equivalent small cell density of over 1000 cells/km2. The LTE-TDD small cells were deployed in 2.6 GHz (Band 41 TDD Config. 1, 60% DL/40% UL) . The venue was chosen due to its extremely challenging RF conditions with a large number of moving objects (each causing different reflections) from trailer trucks to racecars and spectators
The highly dynamic environment made it impossible to plan the network ahead of time. While the small cells are installed and provisioned before the race when the venue is quiet and empty, there is a huge influx of staff and equipment on the day of the race. In one instance, one trailer truck parked immediately in front of a small cell, thus changing the RF environment for that cell completely. Such events put UltraSON to the test to adapt to the constantly changing terrain.
The demonstration showed that:
- Hyper-dense small cell networks delivered over 40 times the efficiency compared to that of a traditional Cell-On-Wheels (COWs)1 deployment.
- In such an environment and with such high small cell density, the UltraSON features, in particular the Frequent Handover Mitigation, were able to reduce the handover rate by half. The resulting benefit was a 60% signaling load reduction for the core network.
- UltraSON power and resource management features contributed to interference reduction, leading to SINR increase, and provided better user experience for cell edge users.
As a result, better performance was observed on the small cell network for a variety of applications.
If UltraSON can enable a hyperdense, unplanned small cell deployment in an environment such as the Pheonix International Raceway with the benefits shown above, then such a deployment method should work in many other environments. Refer to the whitepaper on the NASCAR trial for more details about the test configuration and performance improvements.