SmarTek Systems SAS-1 Intro and Background - Manual (Page 3)

SmarTek Systems (www.smarteksys.com) 3
Introduction
The SmarTek Systems Acoustic
Sensor -Version 1 (SAS-1) is a
non-contact, passive acoustic
(listen only) sensor for multi-
lane traffic monitoring at all
speeds from free flow to stop
and go. It is completely non-
intrusive to the highway or to
the travelers using the highway.
The very compact and
lightweight SAS-1 is designed
to be quickly and easily
installed on existing roadside
highway structures and operates
from a “sidefire” position. For
this position, no lane closures
are needed for a typical
installation. Reliability for the
adverse highway environment is
designed into the SAS-1 to
eliminate periodic maintenance
requirements.
The SAS-1 utilizes SmarTek Systems’ advanced signal and spatial processing technology to
provide high resolution “acoustic imaging” of all vehicle traffic passing by the sensor (including
shoulder activity). This advanced processing eliminates false vehicle detections caused by out of
lane or off road noise. Because the SAS-1 “acoustically images” the highway traffic with a large
number of high resolution cells (look directions), the end user is provided with significant
flexibility to electronically position each detection zone and to set each detection zone’s size and
sensitivity. This capability eliminates the need for precise mechanical “pointing” of the SAS-1
during installation. After installation, final detection zone positioning and repositioning is
accomplished using SmarTek Systems’ SAS Monitor and Setup software. This software runs
on a Windows PC and displays the position (Traffic Acoustic Image-TAI) of every vehicle in
real time as they pass the sensor station. The SAS Monitor and Setup software includes several
tools to simplify the installer’s task of setting up the SAS-1 for multi-lane traffic monitoring
operation. These tools include an Automatic Lane Finder and Setup Display, a Detection
Sensitivity Setup Display, and a Speed Calibration Display. Using these tools, the end user
can quickly set each detection zone position, size, and sensitivity for operation. The SAS-1
provides effective and accurate true vehicle presence detection and associated traffic flow
measures on a lane by lane basis for vehicles passing the sensor station at any speed from “stop
and go” to free flow.
Figure 1 SmarTek Systems Acoustic Sensor (SAS-1)
Acoustic Wavefronts
Highway Lanes