The publisher just completed its 27th 5G NR benchmark study. For this endeavour we collaborated with Accuver Americas and Spirent Communications to conduct an independent benchmark study of Voice over New Radio (VoNR) and how it compares with VoLTE, based on testing we did in T-Mobile’s network.
Highlights of the Report include the following:
Acknowledgements
This study was conducted in collaboration with Accuver Americas (XCAL-M and XCAP) and Spirent Communications (Umetrix Voice and Umetrix Data). The publisher is responsible for the data collection and all analysis and commentary provided in this report.
Methodology
Testing took place over a two-day period in early July. The publisher had access to a T-Mobile 17-site test cluster that is part of its commercial network. Using 2 Galaxy S21 with pre-release software that supported VoNR and SA the publisher did comparative drive and stationary testing with two Galaxy S20 smartphones that supported VoLTE. The publisher tested VoNR in both Band n71 (600 MHz) and Band n41 (2500 MHz), including with background data transfers taking place during the call.
Four Areas of Focus
The publisher looked at voice quality (MOS), network resource utilization, background data transfers, and current consumption. The publisher did this comparative testing while stationary and/or via extensive drive testing throughout the cluster where the smartphones were exposed to a wide range of RF conditions.
It's Nuanced
VoLTE offered a huge advantage over circuit switched 3G voice in terms of superior voice quality, not to mention the elimination of CSFB (circuit switched fallback). VoNR and VoLTE both use the same EVS codec so the benefits of VoNR over VoLTE are less obvious.
“Staying Alive” on 5G
Without question, the biggest advantage of VoNR is that it allows the smartphone to remain on 5G, which proves beneficial when background data transfers occur. Longer term, moving all traffic to 5G SA helps with technology migration while SA offers certain performance benefits over NSA that are unrelated to voice.
Balancing Act
5G networks are not as mature as LTE so RF conditions are not always as favorable. 5G current consumption is a consideration, especially when VoNR occurs in Band n41. Lastly, 5G network resource utilization can be better optimized for low bit rate voice calls.
Table of Contents
1.0 Executive Summary
2.0 Key Observations
3.0 VoNR Results and Analysis
3.1 VoLTE and VoNR Stationary Tests with Background Data Transfers
3.1.1 VoLTE
3.1.2 VoNR
3.2 VoLTE and VoNR Drive Test Results
3.3 n71 Versus n41 Drive Test Results
3.4 VoNR Freewheeling Test with Background Data Traffic
3.5 VoLTE and VoNR Current Analysis and Call Setup Times
3.5.1 Current Analysis
3.5.2 Call Setup Times
4.0 Test Methodology
5.0 Final Thoughts
Index of Figures & Tables
Figure 1. VoLTE Voice Quality
Figure 2. Background Data Traffic During a VoLTE Call - Time Series
Figure 3. Background Data Traffic During a VoLTE Call - Median Values
Figure 4. VoNR Voice Quality
Figure 5. Background Data Traffic During a VoNR Call - Time Series
Figure 6. Background Data Traffic During a VoNR Call - Median Values
Figure 7. Background PUSCH Data Traffic with HTTP Uplink Only During a VoNR Call - Time Series
Figure 8. Background PUSCH Data Traffic with HTTP Uplink Only During a VoNR Call - Comparative Results
Figure 9. Uplink MCS and Modulation Scheme Allocations During a VoNR Call - Time Series
Figure 10. VoNR 5G Band Usage
Figure 11. VoLTE 5G Band Usage
Figure 12. VoLTE and VoNR Voice Quality
Figure 13. VoLTE MOS
Figure 14. VoNR MOS
Figure 15. VoLTE MOS Versus LTE SINR - Time Series
Figure 16. VoLTE MOS Versus LTE RSRP - Time Series
Figure 17. VoNR MOS Versus 5G Frequency Band - Time Series
Figure 18. VoNR UE MOS Versus Average SINR - Time Series
Figure 19. VoNR Terminating UE, Originating UE and Average SINR - Time Series
Figure 20. VoNR UE MOS Versus Average RSRP - Time Series
Figure 21. VoNR Originating UE MOS Versus UE SINR Correlations
Figure 22. VoNR Terminating UE MOS Versus UE SINR Correlations
Figure 23. VoNR UE MOS Versus UE RSRP Correlations - Band n71 only
Figure 24. VoLTE Originating and Terminating UE MOS Versus Average SINR Correlations
Figure 25. VoLTE Originating and Terminating UE MOS Versus Average RSRP Correlations
Figure 26. n41 and n71 VoNR MOS
Figure 27. n71 and n41 VoNR MOS
Figure 28. Band n71 VoNR MOS and SINR - Time Series
Figure 29. Band n41 VoNR MOS and SINR - Time Series
Figure 30. Band n41 and Band n71 VoNR MOS Versus Average RSRP Correlations
Figure 31. Band n71 VoNR PDSCH and PUSCH Throughput
Figure 32. Band n41 VoNR PDSCH and PUSCH Throughput
Figure 33. Band n41 and Band n71 VoNR PDSCH Throughput - Time Series
Figure 34. Band n41 and Band n71 VoNR PUSCH Throughput - Time Series
Figure 35. VoLTE PDSCH and PUSCH Throughput
Figure 36. VoLTE, VoNR n71 and VoNR n41 Median Throughput
Figure 37. VoLTE and VoNR n71 Throughput Relative to n41 Throughput
Figure 38. n71 and n41 Downlink and Uplink Throughput - Time Series
Figure 39. n71 and n41 Downlink and Uplink Throughput - Average
Figure 40. n71 and n41 Downlink and Uplink Spectral Efficiency
Figure 41. n71 and n41 Relative Bandwidth Consumption
Figure 42. Originating and Terminating UE 5G Band Selection
Figure 43. Originating and Terminating UE Voice Quality
Figure 44. Freewheeling MOS
Figure 45. Originating UE PDSCH Throughput
Figure 46. Terminating UE PUSCH Throughput
Figure 47. VoNR Originating and Terminating UE MOS and Average SINR - Time Series
Figure 48. VoNR Originating and Terminating UE MOS Versus Average SINR Correlations
Figure 49. VoLTE Current Drain with 5G Disabled
Figure 50. VoLTE Current Drain with 5G Enabled
Figure 51. VoNR Current Drain with 5G Enabled
Figure 52. VoLTE and VoNR Call Setup Times
Figure 53. VoNR Call Signaling Messages
Figure 54. XCAL-M
Figure 55. Umetrix Data Architecture
Figure 56. Umetrix Voice
Companies Mentioned
- Accuver Americas
- Spirent Communications
- Samsung
- T-Mobile
