🤖 AI Summary
This work addresses the challenge in wireless edge data-intensive broadcasting where existing deep joint source-channel coding schemes struggle to balance distortion, rate, and decoding complexity while failing to accommodate heterogeneous receiver requirements. To this end, the paper proposes a Nonlinear Transform Rateless Source-Channel Coding (NTRSCCC) framework that, for the first time, integrates learnable nonlinear source transformations with physical-layer Luby Transform (LT) codes, enabling variable-length transmission. The framework further incorporates an unequal error protection mechanism guided by receiver-side information. Through end-to-end optimization of rateless parameters and approximate gradient backpropagation, NTRSCC achieves a controllable trade-off among distortion, rate, and complexity. Experimental results demonstrate that under stringent resource constraints, NTRSCC significantly improves image broadcast quality across heterogeneous multi-user edge devices.
📝 Abstract
In recent years, numerous data-intensive broadcasting applications have emerged at the wireless edge, calling for a flexible tradeoff between distortion, transmission rate, and processing complexity. While deep learning-based joint source-channel coding (DeepJSCC) has been identified as a potential solution to data-intensive communications, most of these schemes are confined to worst-case solutions, lack adaptive complexity, and are inefficient in broadcast settings. To overcome these limitations, this paper introduces nonlinear transform rateless source-channel coding (NTRSCC), a variable-length JSCC framework for broadcast channels based on rateless codes. In particular, we integrate learned source transformations with physical-layer LT codes, develop unequal protection schemes that exploit decoder side information, and devise approximations to enable end-to-end optimization of rateless parameters. Our framework enables heterogeneous receivers to adaptively adjust their received number of rateless symbols and decoding iterations in belief propagation, thereby achieving a controllable tradeoff between distortion, rate, and decoding complexity. Simulation results demonstrate that the proposed method enhances image broadcast quality under stringent communication and processing budgets over heterogeneous edge devices.