Diagram showing the remote camera control system for Highway I-77, Charlotte, North Carolina

Along the rolling hills outside of Charlotte, NC along highway I-77, new Intelligent Transportation System (ITS) technology has been implemented that will make it faster to pinpoint accidents and traffic bottlenecks by utilizing controllable video cameras mounted alongside the roadway. These cameras will allow control room dispatchers and traffic managers to view a situation and direct trouble crews to the site of the incident quicker which will save lives and move traffic more efficiently. RFL plays a significant part in this story as the supplier of one of the key elements to this project.

The road side cameras transmit video signals through a high speed redundant network comprised of OC-12 SONET multiplexers. The camera video signals are transmitted through a modem over fiber optic cables directly to the OC-12 SONET multiplexer.

The PTZ (Pan, Tilt and Zoom) control signals from the cameras along side the highway are fed locally to a RFL IMUX 2000 T-1 multiplexer which concentrates the RS-232 asynchronous data control channels into a DS-1 (1.544 Mbps) data stream that is fed into a standard interface on the OC-12 SONET multiplexer. Specialized alarm reporting modules in the IMUX 2000 send various local alarms such as open doors and loss of power conditions to the control center.

All of these systems (the IMUX 2000 and the OC-12 SONET multiplexer) are part of a larger ITS Enterprise Network. These systems or nodes are managed by a common communications protocol known as SNMP (Simple Network Management Protocol). This Protocol allows the user to easily integrate multiple vendor products such as multiplexers, routers, hubs, and computers into a single management platform (i.e. HP Overview). Each product or system is displayed to the user as a node in a certain color. Different colors indicate a normal or alarm condition to the operator. If in an alarm state the user can simply click on the node to bring up the control and reporting software specific to the node in question and interrogate the system in a windows environment to locate the problem.

The IMUX 2000 is purposely designed for use in large enterprise networks such as a camera control system. The product can also be applied in stand alone applications such as a traffic control communication network for a municipality. The IMUX 2000 lends itself to these applications because of the versatility that is designed in the standard network management software, or the optional SNMP interface, and the wide range of transportation specific channel cards.

This is another example of how RFL is working with Transportation Authorities in creating safer roadways.

For more information about RFL Electronics Inc. or how we can help make your highway a safer place to travel, please call our factory.