Hs60 Overview - Simrad HS60 User Manual

Differential operation
The purpose of differential GPS (DGPS) is to remove the effects of
selective availability (SA), atmospheric errors, timing errors, and
satellite orbit errors, while enhancing system integrity. Autonomous
position capabilities of the HS60 will result in position accuracies of
3 m 95% of the time. In order to improve position quality to bet-
ter than 1.0 m 95%, the HS60 is able to use differential corrections
received through the internal SBAS demodulator.
Automatic SBAS tracking
The HS60 automatically scans and tracks SBAS signals without the
need to tune the receiver. The HS60 features two-channel tracking
that provides an enhanced ability to maintain a lock on an SBAS
satellite when more than one satellite is in view. This redundant
tracking approach results in more consistent tracking of an SBAS
signal in areas where signal blockage of a satellite is possible.

HS60 overview

The HS60 provides accurate and reliable heading and position infor-
mation at high update rates. To accomplish this task, the HS60 uses
a high performance GPS receiver and two antennas for GPS signal
processing. One antenna is designated as the primary GPS antenna
and the other is the secondary GPS antenna. Positions computed
by the HS60 are referenced to the phase center of the primary
GPS antenna. Heading data references the vector formed from the
primary GPS antenna phase center to the secondary GPS antenna
phase center.
The heading arrow located on the bottom of the HS60 enclosure
defines system orientation. The arrow points in the direction the
heading measurement is computed (when the antenna is installed
parallel to the fore-aft line of the vessel). The secondary antenna is
directly above the arrow.
Supplemental sensors
The HS60 has an integrated gyro and two tilt sensors. The gyro and
tilt sensors are enabled by default. Both supplemental sensors are
mounted on the printed circuit board inside the HS60.
The sensors act to reduce the search volume, which improves head-
ing startup and reacquisition times. This improves the reliability and
accuracy of selecting the correct heading solution by eliminating
other possible, erroneous solutions. See Sensor operation summary
table on next page.
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Operation | HS60 GPS Compass User Guide