CSI Wireless Seres, Reference Manual

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Seres Reference Manual
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Q - How do I know what the GPS inside the Seres is doing?
A - The GPS engine within the Seres supports standard NMEA data
messages. The $GPGSV data message contains satellite tracking
information. Since the GPS automatically tracks GPS satellites when
powered, this will give you information on the tracking status. If your
receiver has computed a position, this will be contained within the
$GPGGA data message.
Q - Do I have to be careful when using the Seres to ensure that it tracks
properly?
A – For best performance, you have to be careful such that the
hemisphere above the Seres is unobstructed for satellite tracking. The
Seres is tolerable of a certain amount of signal blockage due to the
availability of redundant satellites (only four are required for a position).
However, as more satellites are blocked, the more impact this could have
your positioning accuracy.
6.6 SBAS Reception and Performance
Q - How do I know if I can receive a SBAS signal in my area?
A - Refer to Chapter 1 that contains approximate coverage maps for both
WAAS (for North America) and EGNOS (for Europe). It’s important to
have both signal coverage and ionospheric map coverage. In fact, it’s
desirable to have a few degrees of latitude and longitude of ionospheric
map coverage around your location to ensure that satellites available have
these correctors.
Q - How do I know if the Seres antenna has acquired a SBAS signal?
A - The Seres antenna allows you to request the output of the $RD1
message that contains the SBAS bit error rate (BER) for both receiver
channels. The BER value describes the rate of errors received from SBAS.