Hemisphere GPS Crescent Vector H220, Руководство интегратора

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H220 Integrator Guide Chapter 2 – Board Overview Page 18 of 28
Receiver Mounting
The H220 is a precision instrument. To ensure optimal operation, consider mounting the receiver
to minimize vibration and shock.
When mounting the H220 immediately adjacent to the GNSS antenna, Hemisphere GNSS highly
recommends shielding the board from the LNA of the antenna.
Note: This step can be more complex than some integrators initially estimate. Attempt to confirm
the operation in your application as early in the project as possible.
The inclusion of the tilt sensor and gyro in the H220 makes it more complicated to configure than
many traditional pieces of GNSS equipment. The following steps summarize the primary
installation steps and the things you need to consider to successfully install the H220.
Mounting the Antennas
The H220 is compatible with the following Hemisphere GNSS single-frequency and L-band
capable antennas:

A21 A25, and A31 (beacon)
When mounting the antennas, consider the following:

Mounting orientation (parallel or perpendicular)

Proper antenna placement
Mounting Orientation
The H220 outputs heading, pitch, and roll readings regardless of the orientation of the antennas.
However, the relation of the antennas to the boat’s axis determines whether you will need to enter
a heading, pitch, or roll bias. The primary antenna is used for positioning and the primary and
secondary antennas, working in conjunction, output heading, pitch, and roll values.
H220 Orientation and Sensor Calibration
The H220 can determine mounting orientation in 90-degree steps using integrated inertial
sensors. This allows the receiver to be installed in various orientations without affecting
performance. A simple one-time calibration procedure is required to complete the orientation and
sensor calibration:
1. Determine which of Group A, B, C or D the installation matches
2. Send the appropriate $JATT,ACC180,YES/NO and $JATT,ACC90,YES/NO commands
that match the installation (as shown in Figures 2-6, 2-7, 2-8 and 2-9)
3. Send the command $JATT,TILTCAL to finalize the calibration
Note: Regardless of which mounting orientation you use, the H220 provides the ability to
output the heave of the machine via the $GPHEV message. For more information on this
message refer to the
HGNSS Technical Reference Guide .