CSI Wireless DGPS MAX User Manual

Vector Sensor Reference Manual 55
Depending on each manufacturer’s goals for a product, they may have the need to combine data
into custom messages, which allows them to improve communication and programming efficiency.
The standard NMEA standard provides for manufacturers to define their own custom, proprietary
messages as required. Proprietary NMEA messages are likely to be supported only by the specific
manufacturer and partners.
The Vector Sensor supports a variety standard and proprietary NMEA messages. These messages
are used to configure the Vector Sensor and also contain the required information from the
system. You may configure a selection of NMEA 0183 data messages on one port at various
update rates (each message has a maximum update rate) and a different selection of NMEA 0183
messages with different rates on the other port.
Chapter 6 presents information relating to the NMEA interface of the Vector Sensor. Appendix D
- Resources provides contact information should you wish to purchase a copy of the NMEA 0183
standard.
4.2.2 Binary Interface
Binary messages may be output from the Vector Sensor along with NMEA 0183 data. Binary
messages have a proprietary definition that likely will require custom software support if you wish
to use it. Binary message inherently are more efficient than NMEA 0183 and would be used when
you require maximum communication efficiency. Use of binary messages for most users is not
recommended as the NMEA interface allows you to control the operation of the Vector Sensor
and also receive all necessary data regarding status and positioning information. Binary messages
are described in Chapter 7.
4.2.3 RTCM SC-104 Protocol
RTCM SC-104 is a standard that defines the data structure for differential correction information
for a variety of differential correction applications. It has been developed by the Radio Technical
Commission for Maritime services (RTCM) and has become an industry standard for
communication of correction information. RTCM is a binary data protocol and is not readable via
a terminal program. It appears as ‘garbage’ data on-screen since it is a binary format and not ASCII
text. The following is an example of how the RTCM data appears on-screen.
mRMP@PJfeUtNsmMFM{nVtIOTDbA^xGh~kDH`_FdW_yqLRryrDuhcB\@}N`ozbSD@O^}nrG
qkeTlpLLrYpDqAsrLRrQN{zW|uW@H`z]~aGxWYt@I`_FxW_qqLRryrDCikA\@Cj]DE]|E@
w_mlroMNjkKOsmMFM{PWDwW@HVEbA^xGhLJQH`_F`W_aNsmMFM[WVLA\@S}amz@ilIuPqx
~_IZhTCpLLrYpdP@kOsmMFM[kVDHwVGbA^P{WWuNt_SW_yMsmMnqdrhcC\@sE^ZfC@}vJm
NGAHJVhTCqLRryrdviStW@H_GbA^P{wxu[K
RTCM has various levels of detail, however the highest level is the message. RTCM defines
numerous messages that contain specific information. The Vector Sensor processes the C/A code
for positioning and does not support more advanced methods of differential such as real-time
kinematic (RTK) positioning that uses different RTCM message types. Considering this fact, the
following RTCM messages are important for use with the Vector Sensor.
• Type 1 and Type 9 messages, both of which contain similar information. These two messages contain
pseudorange corrections and range rate corrections to each GPS satellite.

CSI Wireless DGPS MAX Specifications

General

Brand	CSI Wireless
Model	DGPS MAX
Category	Receiver
Language	English