Motor vehicle on-board power system and method for transmitting data signals in a motor vehicle on-board power system

A motor vehicle on-board power system, comprising:

• electrical supply lines;
• a number of consumers each connected to one of said electrical supply lines;
• communication units, each of said communication units integrated into a respective one of said consumers for data transmission and is assigned in each case to at least a plurality of said consumers, each individual communication unit configured as a repeater forwarding received data to a next communication unit, unless the received data is intended for the current consumer;
• and
• a plurality of subnet works separated from one another and not interconnected, such that no line-connected data transmission is possible between the subnet works, said communication units are configured such that, using said electrical supply lines, they set up a meshed data network extending over separate ones of said subnet works, said communication units forming network nodes of the meshed data network, and process data which are made available by said consumers and transmit the data as a data signal via said supply lines so that communications between said communication units in said separate subnet works is enabled;
• wherein the data signal is a high-frequency data signal and said electrical supply lines are unshielded so that the data signal injects from one of said electrical supply lines into a further one of said electrical supply lines during operation without a galvanic connection, with data communication beyond the boundaries of a subnet work occurring via a crosstalk effect.