Haicom HI-203E Mini-Din Use Manual

Also see for HI-203E: User manual User guide

Contents

Haicom HI-203E Mini-Din Use Manual Manual pdf 7 page image

SECTION 2RECEIVER OPERATIONUpon power up, after initial self-test has completed, the HI-203E will beginsatellite acquisition and tracking process. Under normal open-sky condition,position-fix can be achieved within approximately 45 seconds (within 15seconds if valid ephemeris data is already collected from recent use). Afterreceiver position has been calculated, valid position, velocity and timeinformation are transmitted through the on board serial interface.The receiver uses the latest stored position, satellite data, and currentRTC time to achieve rapid GPS signal acquisition and fast TTFF. If thereceiver is transported over a large distance across the globe, cold-startautomatic-locate sequence is invoked. The first position fix may take upto five minutes searching the sky for the GPS signal. The acquisitionperformance can be improved significantly if the host initializes thereceiver with a rough estimate of time and user position.As soon as GPS signal is acquired and tracked, the HI-203E willtransmit valid navigation information through its serial interface. Thenavigation data contains following information:• Receiver position in latitude, longitude, and altitude• Receiver velocity• Time• DOP error-magnification factor• GPS signal tracking statusThe HI-203E will perform 3D navigation when four or more satellites aretracked. When three or fewer satellites are tracked, altitude-hold is enabledusing the last computed altitude and 2D navigation mode is entered.With signal blockage or rising and setting of the satellites, where achange in satellite constellation used for position fix occurred, largeposition error may result. The HI-203E incorporates a proprietaryalgorithm to compensate the effect of satellite constellation change, andmaintains an accurate smooth estimate of the receiver position, velocity,and heading.6