The present invention relates to a downhole well-operation system for operating a driving unit and a logging tool downhole and transmitting well-logging data from at least one logging tool to a surface data acquisition system by means of a wireline. The system comprises a surface transceiver, a wireline, a downhole transceiver, a logging tool, and a driving unit, wherein the downhole transceiver is coupled to the surface transceiver via the wireline and communicates to the surface transceiver using orthogonal frequency division multiplexing to transmit data via the wireline by modulating a Pulse Width Modulated (PWM) signal to the wireline by means of a transistor bridge, while the driving unit and at least one logging tool is powered by the wireline. Furthermore, the invention relates to a downhole tool.