Transformers for Green Semantic Communication: Less Energy, More Semantics
Shubhabrata Mukherjee, Cory Beard, Sejun Song
TL;DR
The paper addresses the lack of universal metrics tying semantic fidelity to energy usage in SemCom by introducing Energy-Optimized Semantic Loss (EOSL), a multi-objective criterion that guides transformer-based encoder/decoder selection. EOSL jointly accounts for semantic loss, channel loss, and energy expenditures, formalized as $EOSL = \sum_{j=1}^{n} {\{ \lambda_{sm}(1 - S_{sm_j}(M_i, M_p)) + \lambda_{lch}(L_{ch_j}) + \lambda_{e_c}(\frac{E_{c_j}}{E_{c,max}}) + \lambda_{e_s}(\frac{E_{s_j}}{E_{s,max}}) \}}$, and is used for model selection rather than training. Through experiments with image-to-text and text-to-image tasks, the authors benchmark CPU/GPU energy across five encoders and demonstrate that EOSL-guided selection can achieve up to 90% energy savings and about 44% improvement in semantic similarity during inference, with decoders consuming substantially more energy than encoders. The work lays the groundwork for greener SemCom architectures by enabling energy-aware inference-time model selection and cross-modal semantic optimization across resource-constrained platforms.
Abstract
Semantic communication aims to transmit meaningful and effective information, rather than focusing on individual symbols or bits. This results in benefits like reduced latency, bandwidth usage, and higher throughput compared with traditional communication. However, semantic communication poses significant challenges due to the need for universal metrics to benchmark the joint effects of semantic information loss and practical energy consumption. This research presents a novel multi-objective loss function named "Energy-Optimized Semantic Loss" (EOSL), addressing the challenge of balancing semantic information loss and energy consumption. Through comprehensive experiments on transformer models, including CPU and GPU energy usage, it is demonstrated that EOSL-based encoder model selection can save up to 90% of energy while achieving a 44% improvement in semantic similarity performance during inference in this experiment. This work paves the way for energy-efficient neural network selection and the development of greener semantic communication architectures.
