A radio device (100) sends a radio transmission (503, 507) to a further radio device (150). Further, the radio device (100) receives a further radio transmission (505, 509) from the further radio device (150). The further radio transmission (505, 509) comprises an indicator of reception success. In response to the indicator being toggled with respect to a previous state of the indicator, the radio device (100) determines that the radio transmission (509) was successfully received by the further radio device (150). In response to the indicator not being toggled with respect to the previous state of the indicator, the radio device (100) determines that the radio transmission (503) failed.