Wavetronix SmartSensor HD Manual page 5

SmartSensor HD Bid Specification
1.0 General. This item shall govern the purchase of aboveground radar vehicle sensing devices (RVSD) equivalent to the Wa-
vetronix SmartSensor™ HD.
An RVSD detects vehicles by transmitting electromagnetic radar signals through the air. The signals bounce off vehicles in their
paths and part of the signal is returned to the RVSD. The returned signals are then processed to determine traffic parameters.
RVSDs are not affected by normal weather and environmental conditions such as rain, wind, snow, dust, etc. They also do not
require cleaning and can maintain performance over a wide range of ambient temperatures.
RVSDs provide a non-intrusive means of detecting traffic because they can be installed at the side of a roadway. This property not
only makes them safer to install but also more cost effective than sensors that require roadway modifications or placement.
2.0 Measured Quantities. The RVSD shall provide volume, average speed, occupancy, classification counts, 85th percentile speed,
average headway, average gap, speed bin counts and direction counts for user-configurable time intervals for up to 22 lanes of
traffic.
The RVSD shall provide up to eight length-based classification bins.
The RVSD shall provide up to 15 speed bins.
The RVSD shall provide speed, length, class, lane assignment, and range data for each vehicle detection.
The RVSD shall provide presence data for up to 22 lanes of traffic.
3.0 Detectable Area.
3.1 Maximum Lanes. The RVSD shall be able to detect and report information from up to 22 lanes.
3.2 Detection Range. The RVSD shall be able to detect and report information in lanes with boundaries as close as 6 ft.
(1.8 m) from the base of the pole on which the RVSD is mounted.
The RVSD shall be able to detect and report information in lanes located with the far boundary at 250 ft. (76.2 m) from
the base of the pole on which the RVSD is mounted.
The RVSD shall be able to simultaneously detect and report information from a lane located at the minimum offset and
from a lane located at the maximum range.
3.3 Lane Size and Spacing. The RVSD shall allow any spacing of traffic lanes positioned from the minimum offset to
the maximum range. Gore and unequally sized or spaced lanes shall be handled so that detections from the lanes meet all
performance specifications.
Not all roadways have lanes that lie on evenly spaced intervals. Some roadways have gore, odd-sized medians and unequal lane
sizes. An RVSD should be able to handle all these cases.
3.4 Barrier Performance. The RVSD shall detect vehicles with the specified accuracy in lanes that are adjacent to a barrier
when 50% of a sedan is visible over the barrier from the point of view of the RVSD.
4.0 Performance.
4.1 Volume Accuracy. The volume data shall be within 5% of truth for a direction of travel during nominal conditions. In-
dividual lane volume data shall be within 10% of truth during nominal conditions. The percentage of missed detection and
the percentage of false detections for each lane shall not exceed 15% during nominal conditions. Nominal conditions exist
when average speeds are greater than 10 mph (16 kph) in every lane; when there is less than 20% truck traffic per lane; and
SmartSensor HD
5