Redundant transmission system
A redundant transmission system including two transmitters with respective data paths, the transmitters including packet creators and selectors wherein one transmitter can serve as a master and alternately as a slave while the other transmitter serves to maintain among the two transmitters one master and one slave.
1. A redundant transmission system utilizing Real-Time Transport Protocol comprising:
in transmitter A, packet creator A receiving signal S and sending packets to selector A;
in transmitter B, packet creator B receiving signal S and sending packets to selector B;
selector A and B outputs connected to respective paths A and B;
if the transmitters are communicating then sequence numbers of A and B packets of respective transmitters A and B are synchronized via copying;
in one of the transmitters, the one selector passing packets created by the one transmitter to one selector;
in the other of the transmitters, the other selector passing packets from the one transmitter after they are modified to the other selector; and
wherein signals received on respective paths A and B are merged after faulty packets are removed, the merger of corresponding non-faulty packets resulting in a first non-faulty packet overwriting a second non-faulty packet.
2. The redundant transmission system of claim 1 wherein: if the transmitters are communicating then a faulty packet causes the one transmitter to become the other transmitter; and, the faulty packet causes the other transmitter to become the one transmitter.
3. The redundant transmission system of claim 2 further comprising:
if the transmitters are communicating then transmitter A working as the master transmitter and transmitter B working as the slave transmitter:
a payload, RTP header, and IP+MAC header in the packets sent to selector A;
transmitter A packets transported over path A; and,
path B transporting modified A packets with packet A payloads, the modified A packets having their IP and MAC headers overwritten with packet B IP and MAC headers.
4. The redundant transmission system of claim 3 further comprising:
if the transmitters are communicating then a transmitter B RTP sequence number synchronizer receiving a sequence number from an A packet;
a B packet corresponding to the A packet adopting the A packet sequence number; and,
transmitter B packets ready for transport on path B in the event that transmitter B becomes the master transmitter.