SoftBank and Ericsson Collaborate to Launch Network Support for "Uplink Tx Switching," Accelerating 5G SA Uplink Communications
SoftBank and Ericsson Japan have launched network support for 'Uplink Tx Switching' to speed up 5G SA uplink communications. Expected to improve throughput by ~1.5x, available on select smartphones from Summer 2026.
📋 Article Processing Timeline
- 📰 Published: April 22, 2026 at 20:00
- 🔍 Collected: April 23, 2026 at 00:02 (4h 2m after Published)
- 🤖 AI Analyzed: April 23, 2026 at 06:59 (6h 56m after Collected)
SoftBank Corp. (hereafter "SoftBank") has collaborated with Ericsson Japan K.K. (hereafter "Ericsson") to initiate network support for "Uplink Tx Switching," a technology that realizes faster uplink communications for 5G SA*1 *2. By advancing Carrier Aggregation*3 and MIMO*4, it will achieve even faster and more stable uplink communications. This technology will become sequentially available on select smartphones to be released by SoftBank from summer 2026 (planned) onwards*5.
*1 5G (5th Generation Mobile Communication System) in Stand Alone format. High-speed, large-capacity communication of 5G SA is provided in limited areas. Please check the area map for details.
*2 Supported frequencies: 3.4GHz band, 3.5GHz band, 3.7GHz band
*3 A technology that uses multiple frequency band radio waves simultaneously.
*4 MIMO (Multiple Input Multiple Output): A technology that improves communication speed by transmitting and receiving data simultaneously using multiple antennas.
*5 Provision will begin in parts of the 5G SA area and will be expanded sequentially.
■ Background
In recent years, along with the spread of AI (Artificial Intelligence) and expanded use of social media, users' uplink communication traffic has been increasing, raising the demand for stable and faster uplink communications*6. Anticipating further increases in uplink traffic in the AI era, SoftBank and Ericsson have been working with smartphone chipset vendors since 2024 toward the introduction of "Uplink Tx Switching." Conducting joint performance verifications from the chipset development stage, we have now successfully introduced it to SoftBank's network.
*6 Reference: In the November 2025 edition of the periodically published "Ericsson Mobility Report" (https://www.ericsson.com/ja/reports-and-papers/mobility-report/articles/ai-cloud-and-mobile-set-to-drive-significant-growth-in-uplink-traffic), Ericsson points out that AI-enabled devices and AI agents are driving factors for future increases in uplink traffic.
■ Details and Effects of "Uplink Tx Switching"
Conventionally, when conducting uplink communications using radio waves in the frequency band for the TDD method*7, communication was accelerated by performing Carrier Aggregation with radio waves in the frequency band for the FDD method*8. "Uplink Tx Switching" is a technology defined in 3GPP Release 16. It temporarily stops FDD method communication during TDD method uplink communication, and by performing MIMO communication using multiple antennas in the wider bandwidth TDD method, it achieves even faster uplink communication.
With the introduction of "Uplink Tx Switching," SoftBank anticipates a theoretical improvement of approximately 1.5 times*9 in uplink communication throughput. This will improve the perceived speed when uploading videos and images, making it possible to transmit large volumes of data more comfortably in the AI era.
*7 TDD (Time Division Duplex): A communication method that uses the same frequency band radio waves and switches between uplink and downlink over time.
*8 FDD (Frequency Division Duplex): A communication method that uses different frequency band radio waves for uplink and downlink.
*9 A theoretical value verified by SoftBank in a configuration conducting uplink communication by simultaneously using radio waves from two frequency bands, n1 and n77.
■ Future Outlook
Moving forward, SoftBank will proceed with expanding the compatible models and coverage areas for "Uplink Tx Switching." Furthermore, in cooperation with Ericsson, we aim to further improve uplink communication performance, considering support for MIMO including radio waves in the frequency band used for the FDD method as defined in 3GPP Release 17.
Through the advancement of 5G services utilizing the latest technologies, SoftBank will continue to strive for improvements in communication quality and customer satisfaction.
About Ericsson
Ericsson's high-performance networks provide connectivity to billions of people every day. For 150 years, Ericsson has been a pioneer in developing communication technology, offering mobile communication and connectivity solutions to telecom operators and enterprises. Together with our customers and partners, Ericsson makes the digital world of the future a reality.
www.ericsson.com
Ericsson Press Release
*1 5G (5th Generation Mobile Communication System) in Stand Alone format. High-speed, large-capacity communication of 5G SA is provided in limited areas. Please check the area map for details.
*2 Supported frequencies: 3.4GHz band, 3.5GHz band, 3.7GHz band
*3 A technology that uses multiple frequency band radio waves simultaneously.
*4 MIMO (Multiple Input Multiple Output): A technology that improves communication speed by transmitting and receiving data simultaneously using multiple antennas.
*5 Provision will begin in parts of the 5G SA area and will be expanded sequentially.
■ Background
In recent years, along with the spread of AI (Artificial Intelligence) and expanded use of social media, users' uplink communication traffic has been increasing, raising the demand for stable and faster uplink communications*6. Anticipating further increases in uplink traffic in the AI era, SoftBank and Ericsson have been working with smartphone chipset vendors since 2024 toward the introduction of "Uplink Tx Switching." Conducting joint performance verifications from the chipset development stage, we have now successfully introduced it to SoftBank's network.
*6 Reference: In the November 2025 edition of the periodically published "Ericsson Mobility Report" (https://www.ericsson.com/ja/reports-and-papers/mobility-report/articles/ai-cloud-and-mobile-set-to-drive-significant-growth-in-uplink-traffic), Ericsson points out that AI-enabled devices and AI agents are driving factors for future increases in uplink traffic.
■ Details and Effects of "Uplink Tx Switching"
Conventionally, when conducting uplink communications using radio waves in the frequency band for the TDD method*7, communication was accelerated by performing Carrier Aggregation with radio waves in the frequency band for the FDD method*8. "Uplink Tx Switching" is a technology defined in 3GPP Release 16. It temporarily stops FDD method communication during TDD method uplink communication, and by performing MIMO communication using multiple antennas in the wider bandwidth TDD method, it achieves even faster uplink communication.
With the introduction of "Uplink Tx Switching," SoftBank anticipates a theoretical improvement of approximately 1.5 times*9 in uplink communication throughput. This will improve the perceived speed when uploading videos and images, making it possible to transmit large volumes of data more comfortably in the AI era.
*7 TDD (Time Division Duplex): A communication method that uses the same frequency band radio waves and switches between uplink and downlink over time.
*8 FDD (Frequency Division Duplex): A communication method that uses different frequency band radio waves for uplink and downlink.
*9 A theoretical value verified by SoftBank in a configuration conducting uplink communication by simultaneously using radio waves from two frequency bands, n1 and n77.
■ Future Outlook
Moving forward, SoftBank will proceed with expanding the compatible models and coverage areas for "Uplink Tx Switching." Furthermore, in cooperation with Ericsson, we aim to further improve uplink communication performance, considering support for MIMO including radio waves in the frequency band used for the FDD method as defined in 3GPP Release 17.
Through the advancement of 5G services utilizing the latest technologies, SoftBank will continue to strive for improvements in communication quality and customer satisfaction.
About Ericsson
Ericsson's high-performance networks provide connectivity to billions of people every day. For 150 years, Ericsson has been a pioneer in developing communication technology, offering mobile communication and connectivity solutions to telecom operators and enterprises. Together with our customers and partners, Ericsson makes the digital world of the future a reality.
www.ericsson.com
Ericsson Press Release