Reconfigurable antennas have been a topic of academic research for many years, but as 5G networks continue to densify and the industry begins to look seriously towards 6G, their relevance to real-world telecom infrastructure is becoming increasingly clear. A recent presentation by Prof. Chenhao Qi from Southeast University, Nanjing, China, titled Reconfigurable Antennas for Wireless Communications, offers a timely and technically rich overview of how antenna reconfigurability could influence future radio access network (RAN) design across sub-6 GHz, mmWave and, in the longer term, THz frequency bands. From an infrastructure perspective, the underlying message is straightforward: future networks will operate across far more diverse spectrum and deployment scenarios, and static antenna designs will struggle to deliver the required flexibility, efficiency and performance.
The performance targets associated with 6G go well beyond those of current 5G systems. Improvements are expected not only in peak data rates and spectral efficiency, but also in latency, positioning accuracy, reliability and energy efficiency. Achieving these targets requires networks that can adapt dynamically to changing electromagnetic conditions and physical environments. Today’s RAN deployments already span multiple layers, from sub-6 GHz macro coverage to mid-band capacity and mmWave hotspots. As frequencies increase, propagation becomes more sensitive to blockage, orientation and interference, making adaptability at the antenna level increasingly important.
Reconfigurable antennas are designed to address this challenge by allowing key antenna characteristics, such as operating frequency, radiation pattern and polarisation, to be adjusted dynamically. This adaptability can be achieved either electronically or through physical changes to the antenna structure. Electronically reconfigurable antennas integrate RF components such as PIN diodes, FET switches or MEMS into the antenna design, enabling very fast reconfiguration on timescales suitable for live network operation. Structurally reconfigurable antennas instead rely on physical movement or deformation of radiating elements, including approaches based on movable parts, liquid metals or flexible structures. While these techniques can offer high flexibility, they also introduce mechanical complexity and slower reconfiguration speeds, which can limit scalability in large-scale infrastructure deployments.
From a network infrastructure standpoint, electronic reconfiguration is particularly attractive. Fast switching speeds, compact integration and long-term reliability make it well suited to dense antenna arrays and multi-band base station designs. The ability to support multiple reconfiguration modes within a single antenna system also opens the door to more efficient hardware utilisation. Frequency reconfiguration allows antennas to switch between bands as spectrum availability or traffic demand changes. Polarisation reconfiguration can improve robustness in both line-of-sight and non-line-of-sight conditions by mitigating fading and misalignment. Pattern reconfiguration enables beam steering, null placement and coverage shaping without relying solely on external beamforming networks. In more advanced designs, these capabilities can be combined, allowing frequency, polarisation and radiation pattern to be adapted jointly.
The presentation also highlights how reconfigurable antennas interact with emerging RAN architectures, particularly in the context of integrated sensing and communication (ISAC) and massive MIMO. One example is a dual-band reconfigurable antenna array, commonly referred to as a DBRAA, that supports both sub-6 GHz and mmWave operation within a shared aperture. This reflects a practical reality for infrastructure deployments, where different frequency bands offer complementary advantages and must coexist efficiently. By dynamically forming sub-6 GHz antennas from mmWave elements, the DBRAA architecture enables finer control over antenna spacing and improved performance compared to fixed-position arrays, while also reducing the need for separate antenna hardware.
Another concept explored is the use of reconfigurable pixel antennas to realise electronically movable antenna arrays, described as reconfigurable pixel antenna-based electronic movable-antenna arrays (REMAA). The key insight here is that radiation pattern reconfiguration can be equivalent, from a channel perspective, to physically moving antenna elements. Achieving this electronically avoids the mechanical complexity associated with motor-driven or fluid-based movable antennas. For dense sites and space-constrained installations, REMAA offers a practical path to improved interference management, better multi-user performance and more efficient use of available antenna real estate.
At mmWave frequencies, power consumption and RF chain count remain major concerns for infrastructure providers. Hybrid beamforming architectures have already been adopted to strike a balance between performance and complexity, but the presentation goes a step further by introducing tri-hybrid beamforming. In this approach, digital beamforming, analogue beamforming and electromagnetic beamforming enabled by reconfigurable antennas are jointly optimised. Radiation-centre selection becomes an additional degree of freedom in the beamforming process, increasing design flexibility while reducing the number of active antenna ports. For large-scale mmWave arrays, this translates into higher spectral efficiency and improved energy efficiency, particularly as array sizes grow.
Taken together, these concepts point towards a future in which antenna systems play a far more active role in network optimisation. Reconfigurable antennas have the potential to reduce hardware duplication across frequency bands, improve adaptability to changing propagation conditions and traffic patterns, and support advanced use cases such as ISAC without a proportional increase in cost or power consumption. At the same time, the presentation makes it clear that several challenges remain, including accurate modelling of reconfigurable antennas, their integration into practical beamforming architectures and a deeper understanding of their end-to-end energy efficiency.
As the industry moves towards 6G, antennas are likely to evolve from largely static components into adaptive, software-controlled elements that are tightly integrated with signal processing and network intelligence. Reconfigurable antennas are not a single solution to all future RAN challenges, but they are emerging as an important building block for next-generation telecom infrastructure. For operators, vendors and infrastructure providers, the ideas presented offer a useful glimpse into how antenna technology could shape deployment strategies and network evolution in the years ahead.
The slides of the presentation are available here and the video is embedded below:
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