mmWave: Unlocking Infinite Possibilities of 5G-A Communication

In the global 5G revolution, China stands at the forefront, with over 4 million base stations and over 1 billion 5G users. 5G technology has penetrated 22 key industries, including steel, power, and mining, with over 10,000 successful application cases. As demands for network capacity, latency, and connectivity  continue to rise, wireless network technology is evolving towards 5G-Advanced (5G-A).

5G-A introduces new technologies and expands spectrum applications, delivering larger capacity, more connections, and lower latency. It enables all-domain sensing, ubiquitous intelligence, and seamless air-space-ground integration, pushing the boundaries of traditional wireless communication.

In this evolution, millimeter wave (mmWave) technology injects new impetus into 5G-A networks. ZTE, a pioneer in mmWave product solutions, has been committed to advancing this technology and exploring its potential applications. This article delves into the characteristics and applicable scenarios of mmWave technology, uncovering how mmWave ushers in a new era of wireless communication.

mmWaves: Building Blocks of 5G-A

mmWaves refer to the electromagnetic spectrum from 30 GHz to 300 GHz, with wavelengths ranging from 1 mm to 10 mm. Compared to the traditional sub-6 GHz, mmWaves exhibit remarkable physical characteristics (Fig. 1), unlocking new possibilities for high-speed communication and precision services.

Ultra-Large Bandwidth: Gigabit-Level Capabilities

mmWave technology offers up to 26.75 GHz of available bandwidth, covering multiple key frequency bands. With 800 MHz of spectrum resources, the peak rate for a single user in the uplink and downlink can reach 2 Gbps and 6.8 Gbps, respectively, enabling an unprecedentedly smooth experience for large video downloads and real-time live-streaming uploads.

Millisecond-Level Latency: Extreme Response Speed

With a sub-carrier spacing of 120 kHz and a slot duration of only 0.125 ms—one-fourth that of sub-6G NR—mmWave significantly reduces the physical-layer latency. This provides strong support for business scenarios with extremely high latency requirements, such as industrial IoT, AR/VR, cloud gaming, and real-time computing.

Concentrated Beam Energy for Precise and Efficient Coverage

mmWaves have short wavelengths and small antenna elements, making them more suited for large-scale antenna array products. When combined with beamforming technology, they enable precise coverage and efficient transmission. This increases the concentration of energy, reduces the transmission power required from a single antenna, and improves energy efficiency.

Precise Sensing: Expanding Boundaries of Communication Applications

mmWave base stations can use the characteristics of direct, reflected, and scattered radio waves to achieve target ranging, speed measurement, and angle measurement, providing strong support for fields such as the low-altitude economy, waterway management, and intelligent transportation.

While mmWave offers remarkable advantages, it faces coverage challenges due to greater penetration loss and weaker diffraction compared to sub-6 GHz frequencies. Therefore, it is essential to maximize its potential in the most suitable scenarios. ZTE has found that mmWaves are not only applicable to scenarios without obstruction (LOS paths), such as outdoor squares, indoor hotspots, and large stadiums, but also in long and narrow spaces with obvious multipath effects, such as rail transit tunnels and outdoor streets. By utilizing multiple reflections and multipath superposition, mmWave can provide an excellent communication experience.

ZTE: Leading mmWave Innovation

As a leading provider of mmWave solutions, ZTE makes breakthroughs with innovations like flexible networking architectures and frame-format designs to meet diverse business needs across different scenarios. It also combines indoor and outdoor product models to support full-scenario deployments.

Multiple Networking Architectures to Ensure Coverage

The NSA architecture leverages existing 4G infrastructure for rapid deployment, while the SA architecture delivers excellent network performance with high data rates, low latency, and high reliability. ZTE’s NSA and SA networking solutions have been commercially deployed on a large scale in Italy. Based on the SA infrastructure, ZTE further supports NR dual connectivity (DC) and NR carrier aggregation (CA), providing more configuration options while meeting diverse business needs and ensuring network performance.

Flexible Frame-Format Design to Meet Tidal Service Demands

ZTE has pioneered a flexible frame-format design for mmWave. Each 0.625 ms cycle contains one full downlink time slot and one full uplink time slot, and the remaining three time slots can be flexibly scheduled according to real-time service needs. This design enables the mmWave system to flexibly adjust uplink and downlink capacity, meeting the needs of diverse scenarios.

Large-Bandwidth Macro AAUs for Excellent Performance

In July 2024, ZTE achieved the industry's fastest mobile speed at 30.8 Gbps through NR-DC networking in Malaysia. In later September, it collaborated with Qualcomm to verify performance using a smartphone test terminal under NR-DC networking combined with 1024QAM modulation, achieving a peak single-user rate of 9.34 Gbps.

MiCell, the Distributed Micro-Cell Solution for Diverse Deployment Scenarios

ZTE took the lead in launching the mmWave distributed micro-station, MiCell, which uses intermediate frequency pooling technology to miniaturize the front-end equipment, supporting easy, quick deployment and expansion, and fulfilling the application requirements of large indoor spaces.

ZTE's mmWave Commercial Practice

ZTE’s mmWave solutions have been commercially implemented since 2020 across multiple countries, including China, Italy, and Thailand, supporting various scenarios such as FWA, large-bandwidth backhaul, free-roam XR, and live streaming (Fig. 2).

mmWave FWA: Leading a New Era of Fixed Wireless Broadband Access

Fixed wireless access (FWA) uses wireless technology to achieve fixed-broadband access. It is characterized by rapid deployment, low cost, and wide coverage. The ultra-large bandwidth of mmWaves can provide higher system capacity and speeds, further enhancing the end-user experience. ZTE has successfully delivered mmWave FWA solutions for multiple operators in Italy, ensuring a 1 Gbps download speed for more than 20,000 household users, meeting their demand for high-speed internet access.

Gigabit-Level Backhaul for Shanghai Metro

In subway tunnels, traditional 5G leaky cable upgrades are costly, time-consuming and face practical problems such as insufficient space and limited power capacity. ZTE’s "dual-use for train and ground" solution, implemented on Shanghai Metro Line 4, builds a a gigabit-level backhaul system without needing leaky cable renovation by deploying mmWave AAUs inside the subway tunnel. Meanwhile, a 5G digital indoor distribution system is deployed inside the carriages. With a downlink backhaul capacity of up to 15 Gbps, mmWave enables over 1,800 passengers to enjoy high-definition videos simultaneously.

Free-Roam XR: Enabling Immersive Experience

mmWave has rejuvenated free-roam XR by eliminating the need for the bulky backpack for local image rendering, allowing users to enjoy the high-definition immersive experience through cloud rendering. In November 2024, ZTE cooperated with USUNHOME Group to launch the world’s first 5G-A VR immersive theater application called “Jimmy Picture Book Metaverse Drama—My World is All You.” Leveraging the large capacity, low latency of mmWaves, and intelligent XR service guarantee technology, users can easily enjoy the ultimate XR experience. This innovation sets a milestone for the entertainment industry.

Gigabit-Level Production and Broadcasting: mmWave Revolutionizing Live Streaming  

Traditional wired live streaming for large-scale events is limited by complex wiring, restricting camera placement and shooting ranges. ZTE’s gigabit-level mmWave network offers a new wireless live streaming solution. During the 2024 Spring Festival Gala, ZTE’s Micell mmWave micro-station guaranteed high-definition live streaming from multiple wireless mobile cameras throughout the event. In August of the same year, Malaysia’s National Games adopted ZTE’s mmWave macro AAU solution, successfully completing the first wireless live streaming of the event via Radio Televisyen Malaysia. This solution enabled photographers to travel light and shoot flexibly, while ultra-low latency realized seamless integration of wireless and wired footage for a multi-angle, immersive viewing experience. mmWave is ushering in a new era of live streaming with greater freedom and richer visuals.

mmWave: Unfolding a New Chapter in Innovative Applications

With ongoing improvements of the industrial chain, including chips, modules, and various types of terminals, along with the increasing maturity of network equipment technology, mmWave applications are expanding into more industries. Among these, integrated communication and sensing with mmWave has emerged as a key technology in the low-altitude economy.

Communication-sensing integration features tight integration of communication and sensing technologies, addressing two core demands of the low-altitude economy: communication and supervision. In addition to traditional communication functions, the mmWave communication-sensing integrated station can accurately track drones’ flight trajectory, speed, longitude, and latitude in real time, report the data to a management platform for effective supervision, and ensure safe and orderly low-altitude flights.

As the industry continues to overcome technical challenges in mmWave propagation, cost, and integration, mmWave technology is gradually becoming a more practical and reliable commercial solution. We look forward to the new chapter that mmWave will bring to the future of wireless communication.