Receive attenuation system for trainline communication networks
View Patent ↗A receive attenuation system for a trainline communication system utilizing an intra-consist electrical cable has an analog front end amplifier, a trainline communication processor, an adjustable attenuator, and a gain controller. The trainline communication processor is configured to generate a receive gain control signal configured to control receive gain of the analog front end amplifier. The adjustable attenuator is capable of being coupled to the intra-consist electrical cable and configured to variably attenuate signals received from the intra-consist electrical cable before transmitting the signals to the analog front end amplifier. The gain controller is coupled to the adjustable attenuator and configured to detect the receive gain control signal generated by the trainline communication processor, determine a supplemental attenuation control value based on the detected receive gain control signal, and control the adjustable attenuator according to the supplemental attenuation control signal.
1. A receive attenuation system for a trainline communication system utilizing an intra-consist electrical cable, the system comprising:
an analog front end amplifier;
a trainline communication processor configured to generate a receive gain control signal configured to control receive gain of the analog front end amplifier;
an adjustable attenuator capable of being coupled to the intra-consist electrical cable and configured to variably attenuate signals received from the intra-consist electrical cable before transmitting the signals to the analog front end amplifier; and,
a gain controller coupled to the adjustable attenuator and configured to:
detect the receive gain control signal generated by the trainline communication processor,
determine a supplemental attenuation control value based on the detected receive gain control signal, and
control the adjustable attenuator according to the supplemental attenuation control signal.
2. The receive attenuation system of claim 1 , wherein the analog front end amplifier is configured to further attenuate the signal transmitted from the adjustable attenuator.
3. The receive attenuation system of claim 1 , wherein the adjustable attenuator is a daughtercard.
4. The receive attenuation system of claim 1 , wherein the gain controller is a daughtercard.
5. The receive attenuation system of claim 1 , wherein the receive gain control signal includes a five bit digital signal.
6. The receive attenuation system of claim 1 , wherein the trainline communication processor is part of an Ethernet bridge for the trainline communication system.
7. The receive attenuation system of claim 6 , wherein the analog front end amplifier is part of the Ethernet bridge for the trainline communication system.
8. The receive attenuation system of claim 1 , wherein the supplemental attenuation control value is determined based on data stored in a configuration file.
9. The receive attenuation system of claim 1 , wherein the gain controller controls the adjustable attenuator using a digital command.
10. The receive attenuation system of claim 1 , wherein the gain controller controls the adjustable attenuator using an analog signal.
11. A method of adjusting receive attenuation in a trainline communication system, the method comprising:
detecting a receive gain control signal generated by a trainline communication processor, wherein the receive gain control signal is configured to control receive gain of an analog front end amplifier;
determining a supplemental attenuation control value based on the detected receive gain control signal, and
controlling an adjustable attenuator according to the supplemental attenuation control signal, the adjustable attenuator coupled to an intra-consist electrical cable and configured to variably attenuate signals received from the intra-consist electrical cable before transmitting the signals to the analog front end amplifier.
12. The method of claim 11 , wherein the method is performed by a gain controller including a daughtercard.
13. The method of claim 11 , wherein the receive gain control signal includes a five bit digital signal.
14. The method of claim 11 , wherein controlling the adjustable attenuator includes controlling the adjustable attenuator using a digital command.
15. The method of claim 11 , wherein controlling the adjustable attenuator includes controlling the adjustable attenuator using an analog signal.
16. A locomotive consist comprising:
an intra-consist electrical cable;
a first locomotive having a first access point configured to transmit signals via the intra-consist electrical cable;
a second locomotive having a second access point including:
an Ethernet bridge including a trainline communication processor configured to generate receive gain control signals;
an analog front end amplifier coupled to the Ethernet bridge and configured to receive the gain control signals from the trainline communication processor;
an adjustable attenuator coupled to the intra-consist electrical cable and the analog front end amplifier, the adjustable attenuator configured to variably attenuate the signals received from the first access point via the intra-consist electrical cable before transmitting the received signals to the analog front end amplifier; and
a gain controller coupled to the adjustable attenuator configured to:
detect the receive gain control signals generated by the trainline communication processor,
determine a supplemental attenuation control value based on the detected receive gain control signal, and
control the adjustable attenuator according to the supplemental attenuation control signal.
17. The locomotive consist of claim 16 wherein the gain controller and the adjustable attenuator constitute on one or more daughtercards.
18. The locomotive consist of claim 16 wherein the receive gain control signal includes a five bit digital signal.
19. The locomotive consist of claim 16 wherein the adjustable attenuator is controlled using a digital command.
20. The locomotive consist of claim 16 wherein the adjustable attenuator is controlled using an analog signal.