Technologies That Enable Congestion Pricing—A Primer
Acronym List/Glossary
ALPR—Automatic License Plate Recognition. Software that enables authorities to match the vehicle license plate with identity information in registration data.
ALS—Area Licensing Scheme. Singapore’s ALS, operated from 1975 until 1998, required car drivers entering the CBD during the morning peak to pay three Singapore dollars per day (with exemptions for vehicles carrying four or more people).
ATM—Automated Teller Machine. A computerized telecommunications device that provides the customers of a financial institution with access to financial transactions without the need for a human clerk or bank teller.
CCTV—Closed-Circuit Television. The use of video cameras to transmit a signal to a specific place, such as a limited set of monitors.
CBD—Central Business District. The commercial and often geographic heart of a city.
CEN—European Committee for Standardization. The CEN was founded in 1961 by the national standards bodies in the European Economic Community and European Free Trade Association countries. CEN contributes to the objectives of the European Union and European Economic Area with voluntary technical standards, which promote free trade, the safety of workers and consumers, interoperability of networks, environmental protection, exploitation of research and development programs, and public procurement.
DSRC—Dedicated Short-Range Communications. A short- to medium-range communications service that supports both public safety and private operations in roadside-to-vehicle and vehicle-to-vehicle communication environments.
EMV—Europay, MasterCard, and Visa.
ERP—Electronic Road Pricing. Electronic toll-collection system that prices roads based on usage.
ETC—Electronic Toll Collection. The collection of tolls based on the automatic identification and classification of vehicles by using electronic systems that do not require drivers to stop or slow down.
GHz—Gigahertz. A unit of alternating current (AC) or electromagnetic (EM) wave frequency equal to one thousand million Hertz (1,000,000,000 Hz). The gigahertz is used as an indicator of the frequency of ultra-high-frequency and microwave EM signals.
GLONASS—Global Navigation Satellite System. Based on a constellation of active satellites that continuously transmit coded signals in two frequency bands, which can be received by users anywhere on the earth’s surface to identify their position and velocity in real time based on ranging measurements. The system is a counterpart to the United States’ global positioning system (GPS), and both systems share the same principles in the data transmission and positioning methods. GLONASS is managed for the Russian Federation Government by the Russian Space Forces, and the system is operated by the Coordination Scientific Information Center (KNITs) of the Ministry of Defense of the Russian Federation.
GPS—Global Positioning System. A U.S. space-based radio-navigation system that provides reliable positioning, navigation, and timing services to civilian users on a continuous worldwide basis—freely available to all. For anyone with a GPS receiver, the system will provide location and time.
GPRS—General Packet Radio Service. A packet-oriented mobile data service available to users of Global System for Mobile Communications.
HCV—Heavy Commercial Vehicles. Includes all heavy motor vehicles used for the transportation of passengers for hire, or constructed or used for transportation of goods, wares, or merchandise.
HOT—High-Occupancy Toll. On HOT lanes, low-occupancy vehicles are charged a toll, whereas high-occupancy vehicles are allowed to use the lanes free or at a discounted toll rate.
HOV—High-Occupancy Vehicle. Highway lanes are typically reserved for these vehicles with two or more occupants.
ITS—Intelligent Transportation Systems. An electronic toll-collection system without toll plazas, where all drivers are charged the toll without stopping, slowing down, or being in a specific lane.
IVR—Interactive Voice Response. A phone technology that allows a computer to detect voice and touch tones using a normal phone call.
LED—Light-Emitting Diode. A semiconducter diode that emits light when an electric current is applied.
MUTCD—Manual on Uniform Traffic Control Devices. Defines the standards used by road managers nationwide to install and maintain traffic control devices on all streets and highways. The MUTCD is published by the Federal Highway Administration.
OBU—On-Board Unit. Also called an on-board transponder. The in-vehicle device component of an ETC system. A receiver or transceiver permitting the Operator’s Roadside Unit to communicate with, identify, and conduct an electronic-toll transaction.
ORT—Open Road Tolling. An electronic toll-collection system without toll plazas, where all drivers are charged the toll without stopping, slowing down, or being in a specific lane.
POS—Point of Service (or Sale). A retail shop, a checkout counter, or the location where a transaction occurs.
RF—Radio Frequency.
RFID—Radio Frequency Identification. A technology similar to bar-code technology. With RFID, the electromagnetic or electrostatic coupling in the RF portion of the electromagnetic spectrum is used to transmit signals. An RFID system consists of an antenna and a transceiver, which read the radio frequency and transfer the information to a processing device and a transponder, or tag, which is an integrated circuit containing the RF circuitry and information to be transmitted.
RUC—Road-User Charging. A mechanism through which motorists pay to use a defined area of road, usually through payment of a toll.
U.K.—United Kingdom. The United Kingdom is a state consisting of four countries: England, Northern Ireland, Scotland, and Wales.
UPS—Uninterruptible Power Supply. A device that maintains a continuous supply of electric power to connected equipment by supplying power from a separate source.
U.S.—United States. A constitutional republic consisting of 50 states and 1 federal district.
VII—Vehicle Infrastructure Integration. VII will work toward the deployment of advanced vehicle–vehicle and vehicle–infrastructure communications that could keep vehicles from leaving the road and enhance their safe movement through intersections.
VPS—Vehicle Positioning System. Satellite-based system for vehicle tracking and positioning.
WAVE—Wireless Access in Vehicular Environments. Wireless communications that will let motor vehicles interact with roadside systems to access safety information and travel-related services, even at high speeds.
WiFi—Wireless Fidelity. A term for certain types of wireless local area networks that use specifications in the 802.11 family.
WIM—Weigh in Motion. Devices designed to capture and record truck axle weights and gross vehicle weights as the trucks drive over a sensor.
WiMAX—Worldwide Interoperability for Microwave Access. A telecommunications technology that provides for the wireless transmission of data by using a variety of transmission modes, from point-to-point links to full mobile-cellular-type access.
