Abstract
Modern cellular user equipment (UE) increasingly supports multiple switchable antenna panels and concurrent connectivity to both terrestrial networks (TN) and non-terrestrial networks (NTN), including low-earth-orbit (LEO) satellite links. Existing uplink antenna and link selection schemes suffer from three fundamental limitations: they rely on downlink reference signal measurements as proxies for uplink path quality; they delegate selection to the network via capability reporting and scheduling commands; or they minimize only transmit power without accounting for the transient energy costs of antenna switching, retuning, and baseband chain activation. These limitations render existing approaches suboptimal for emerging multi-panel, multi-link UE architectures – particularly wearables and augmented reality (AR) devices with tight thermal budgets and rapidly varying propagation environments. This paper proposes a fully autonomous, UE-side uplink selection framework based on a five-component total energy cost function: Etotal = Etx + Ebaseband + Eswitching + Etuning + Emargin, where Etx is the transmit energy, Ebaseband is the baseband and RF chain activation energy, Eswitching is the antenna panel and link switching transient energy, Etuning is the antenna retuning and settling energy, and Emargin is an uncertainty margin penalty. The selection is performed entirely on-device using internal UE measurements, impedance/VSWR sensing, power amplifier (PA) telemetry, and inertial measurement unit (IMU)/grip sensing – without network assistance. A forward-looking extension over a prediction horizon T uses satellite ephemeris and Doppler trajectory data to minimize cumulative energy expenditure for NTN links. Joint carrier aggregation (CA) and simultaneous TN+NTN multi-link selection are addressed within the same framework. Hysteresis is enforced by conditioning switching events on the criterion that the reduction in Etx and Ebaseband exceeds the sum of Eswitching and Etuning by a programmable margin. Analytical results demonstrate the validity of the proposed framework across a range of multi-panel and multi-link UE scenarios.
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