Interest in Direct Current Power Line Communication (DC-PLC) is growing as industries seek to reduce wiring complexity and cost by combining power and data over a single medium. A programmable DC-PLC testbed is developed to enable power transfer and bidirectional communication over a shared DC power line bus. The system employs a master–slave scheme in half-duplex mode under a flexible MAC protocol, using Voltage Polarity Modulation (VPM) for downlink and Current Amplitude Modulation (CAM) for uplink. Implemented with low-cost microcontrollers, the master and slave are designed as modular units for easy connection and expansion. The platform achieves approximately 100 kbps throughput in both directions and demonstrates reliable operation with a simple polling-based MAC protocol, highlighting its potential for future DC-PLC research and applications.

Recent advances in electric vehicles, robots, and renewable energy have renewed interest in direct current (DC) power line communication (PLC) technology. However, existing DC-PLC systems face from several limitations, including low data rates, lack of support for duplex communication, and the absence of an effective medium access control (MAC) mechanism. To overcome these challenges, we propose D2-PLC, a novel DCPLC system that features a redesigned physical layer, enabling high-speed duplex communication over a single pair of wires supporting simultaneous power and data transmission. D2-PLC introduces voltage polarity modulation (VPM) and current amplitude modulation (CAM) for downlink and uplink communication, respectively. In addition, we develop a custom data link layer and MAC protocols to coordinate communication in a bus topology where multiple slave nodes interact with a single master node (the power source), minimizing the risk of collisions. We implement a fully functional prototype and evaluate on a 5-node testbed as well as via 256-node simulations. Results demonstrate that D2-PLC achieves a maximum data rate of ~100 kbps–260% improvement over existing solutions(Cwhile maintaining 99+% reliability. These findings highlight D2-PLC’s potential to reduce the cost and weight of battery-powered systems such as electric vehicles