Energy-Efficient Dual-Band Communication: How to Allocate Traffic to Sub-THz Carriers?

2026-07-25

AI Summary

This study addresses the fundamental trade-off between high bandwidth and high power consumption in the evolution toward sub-terahertz (sub-THz) frequencies for 6G networks. It investigates the energy efficiency limits of dual-band base stations combining coverage-oriented sub-6 GHz and capacity-oriented sub-THz bands. By jointly optimizing hardware parameters and an activity-factor-based advanced sleep mechanism, the work identifies four distinct energy-efficiency-optimal operating regions and derives closed-form analytical thresholds for sub-THz carrier activation and traffic offloading. The analysis reveals that activating the sub-THz band significantly reduces total system power consumption when the power cost incurred by the bandwidth limitation of sub-6 GHz exceeds the static power consumption of sub-THz circuitry, thereby offering theoretical foundations and design guidelines for energy-efficient 6G networks.

Abstract

As 6G wireless networks transition toward sub-Terahertz (sub-THz) frequencies to satisfy extreme capacity demands, managing the trade-off between massive bandwidth and power consumption becomes a critical design challenge. In this paper, we investigate the fundamental energy efficiency (EE) limits of a dual-band base station site combining a coverage-oriented sub-6 GHz carrier with a capacity-oriented sub-THz carrier. By jointly optimizing hardware parameters and advanced sleep modes via activity factors, we identify four distinct operational regions that govern the EE-optimal behavior across the complete range of data rates. We derive closed-form analytical thresholds that dictate precisely when the sub-THz band should awaken from sleep and how to allocate traffic between the bands in that case. Our results demonstrate that utilizing the sub-THz band is EE-optimal when the power cost of the bandwidth-limited sub-6 GHz band surpasses the static power penalty of activating the sub-THz circuitry. Ultimately, this framework provides mathematically rigorous guidelines for power consumption minimization and sleep-mode management in future green networks.

Problem

• energy efficiency
• sub-THz
• dual-band communication
• traffic allocation
• power consumption

Innovation

• energy efficiency
• sub-THz
• dual-band communication
• sleep mode optimization
• traffic allocation