Wavetronix SmartSensor V User Manual page 8

˽ Sensors on Opposing Poles – SmartSensor units facing each other on opposing poles
should operate on different RF channels and be separated by a 40-ft. (12.2-m) lateral
offset, if possible.
˽ Line of Sight – The SmartSensor is designed to work accurately in the presence of
barriers, but in general if there is an alternate mounting location that would avoid any
type of structural occlusion, this is preferred. Avoid occlusion by trees, signs, and other
roadside structures.
˽ Neighboring Structures and Parallel Walls – It is also preferred that sensor locations
have a 30-ft. (9.1-m) lateral separation from overhead sign bridges, overpasses, tun-
nels, parallel walls and parallel-parked vehicles in order to avoid multiple reflection
paths from a single vehicle.
Mounting Height – The mounting height should be based upon the offset from the
˽
lanes of interest. For each offset, the minimum, maximum and recommended range
of heights is shown in Table 1.1, found in chapter 1. In general, the range of recom-
mended heights is between 9 and 50 ft. (2.7 to 15.2 m).
˽ Mounting Offset – The minimum recommended offset from the edge of the first lane
of interest is 10 ft. (3 m).
˽ Arterial Locations – Sensor sites on arterials or other roadway segments with regulated
stop lines should be selected at mid-block positions to increase accuracy by increasing
line of sight to stop-and-go vehicles.
Roadway
Figure I.1 – Portable (left) and Permanent (right) Sensor Stations
Freeway Locations – The SmartSensor V is often used at permanent ATR stations. The
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number of stations along a single roadway and the distance between stations should be
selected to achieve adequate levels of statistical confidence. Permanent ATR stations,
which are selected to cover interstate, principal arterial and other national and state
INTRODUCTION • SMARTSENSOR V USER GUIDE
Offset
Roadway
7
Mounting
Height