Which massive MIMO systems are known for energy efficiency and 5G-ready performance?

Some massive MIMO systems and product lines that are commonly recognized for high energy efficiency and 5G-ready performance include:

• Ericsson Radio System / Ericsson Massive MIMO radios
  Known for strong spectral efficiency, integrated radio design, and power-efficient operation for 5G macro deployments.

• Nokia AirScale Massive MIMO
  Designed for 5G NR support with efficient beamforming and good energy-per-bit performance.

• Huawei Massive MIMO AAU solutions
  Widely deployed for 5G, emphasizing compact design, high capacity, and improved energy efficiency.

• Samsung 5G Massive MIMO radios
  Built for sub-6 GHz 5G with strong beamforming and optimized power usage.

• ZTE Massive MIMO base station solutions
  Focus on high throughput, coverage improvement, and energy-saving features for 5G networks.

If you meant academic/technical massive MIMO architectures rather than vendor systems, the most energy-efficient and 5G-aligned approaches are typically:

• Active antenna units (AAUs) with hybrid beamforming
• TDD-based massive MIMO at sub-6 GHz
• Distributed massive MIMO / cell-free massive MIMO
• Low-resolution DAC/ADC massive MIMO designs
• Intelligent power control and sleep-mode massive MIMO architectures

If you want, I can also give you:

1. a vendor comparison table, or
2. a list of the most cited research systems for energy-efficient massive MIMO in 5G.