IEEE 802.3 1000Base-T1
1000Base-T1 is a GbE interface developed by IEEE 802.3bp for automotive Ethernet and industrial applications. Like 10Base-T1 and 100Base-T1, 1000Base-T1 belongs to the Single-Pair Ethernet( SPE) concept. The standard uses a single twisted pair cable, Unshielded Twisted Single Pair( UTSP), Category 6A, with differential signals transmitted in full duplex.
Signals between two SPE electronic control units are transmitted simultaneously in both directions. They overlap and run in opposite directions on the SPE cable. Since the respective transceivers know their transmit signals, they can filter out the receive signals.
The 1000Base-T1 interface is based on BroadR-Reach and has been standardized as Single-Pair Ethernet (SPE) by the IEEE working group 802.3bp. 1000Base-T1 corresponds in its technical values to classic Ethernet. Thus, the frame format and the minimum and maximum frame lengths are retained. The error rate is `10^-10` and the data rate is 1 Gbit/s. The standard can work with autonegotiation and bridge distances of up to 15 m (1000Base-T1A) or 45 m (1000Base-T1B), as found in buses and trucks. As a modulation method, 1000Base-T1 uses the multivalued pulse amplitude modulation PAM3.
The IEEE working group 802.3bu has standardized a procedure for 1000Base-T1 for the transmission of supply voltages via the STP cable under the designation Power over Data Lines( PoDL).