The South Dakota Department of Transportation uses a vast array of electronic equipment and sensors in the field to help accomplish its mission:
Traffic monitoring equipment collects vehicle counts, weights, classifications and speeds;
Road Weather Information Systems (RWIS) measures weather and road conditions for forecasters and traveler information;
Dynamic Message Signs (DMS) display crucial information for travelers;
Winter maintenance equipment may soon collect information along their snow routes regarding road conditions, pavement temperatures, and the rate of application of deicing chemicals;
The Construction Management System (CMS) is used to enter and access information regarding construction projects. Presently users of CMS use phone lines provided at construction project labs, but due to the volume of data that needs to be transferred, users frequently wait until they get back to the office to upload data causing delays;
Pavement distress survey data is collected and stored in laptops for up to a week before being downloaded. A computer failure could result in the loss of important data;
Right-of-Way appraisal and acquisition documents must be transmitted to the central office in a timely manner.
All of this data must be transmitted to the States computer network so that it may be stored, analyzed and used. Currently, phone lines are used for nearly all of these applications, and monthly phone bills to the Department have been increasing. Not only are the operational costs quite large, but the cost of trenching and installing new phone lines are high. Fixed phone lines do not support portable DMSs, which are used for traffic control in work zones, at large events, and during incidents.
This proposed research would determine what wireless technologies exist in South Dakota and investigate a number of them to replace costly phone line communications and establish reliable communications to locations previously inaccessible by fixed phone lines or cellular phone due to its limited coverage. Some examples of wireless technology now available are:
Spread spectrum radio, capable of transmitting over 30 miles and providing over 100kbps data rates;
Global System for Mobile Communications (GSM-IP) providing equipment direct access to Internet providers and allowing constant communications, but charging only for bursts of data;
802.11, the standard for short range wireless networking;
The 150 MHz state radio system, which will provide 9600bps that may suffice in some circumstances, but not all;