Datasheet

NEO-6 - Data Sheet
GPS.G6-HW-09005-E Page 8 of 25
1.7 Precision Timing
1.7.1 Time mode
NEO-6T provides a special Time Mode to provide higher timing accuracy. The NEO-6T is designed for use with
stationary antenna setups. The Time Mode features three different settings described in Table 3: Disabled,
Survey-In and Fixed Mode. For optimal performance entering the position of the antenna (when known) is
recommended as potential source of errors will be reduced.
Time Mode Settings
Description
Disabled
Standard PVT operation
Survey-In
The GPS receiver computes the average position over an extended time period until a predefined
maximum standard deviation has been reached. Afterwards the receiver will be automatically set to
Fixed Mode and the timing features will be activated.
Fixed Mode
In this mode, a fixed 3D position and known standard deviation is assumed and the timing features are
activated. Fixed Mode can either be activated directly by feeding pre-defined position coordinates (ECEF
- Earth Center Earth Fixed format) or by performing a Survey-In.
In Fixed mode, the timing errors in the TIMEPULSE signal which otherwise result from positioning errors
are eliminated. Single-satellite operation is supported. For details, please refer to the u-blox 6 Receiver
Description including Protocol Specification [2].
Table 3: Time mode settings
1.7.2 Timepulse and frequency reference
NEO-6T comes with a timepulse output which can be configured from 0.25 Hz up to 10 MHz. The timepulse can
either be used for time synchronization (i.e. 1 pulse per second) or as a reference frequency in the MHz range. A
timepulse in the MHz range provides excellent long-term frequency accuracy and stability.
1.7.3 Time mark
NEO-6T can be used for precise time measurements with sub-microsecond resolution using the external interrupt
(EXTINT0). Rising and falling edges of these signals are time-stamped to the GPS or UTC time and counted. The
Time Mark functionality can be enabled with the UBX-CFG-TM2 message
For details, please refer to the u-blox 6 Receiver Description including Protocol Specification [2].
1.8 Raw data
Raw data output is supported at an update rate of 5 Hz on the NEO-6T and NEO-6P. The UBX-RXM-RAW
message includes carrier phase with half-cycle ambiguity resolved, code phase and Doppler measurements,
which can be used in external applications that offer precision positioning, real-time kinematics (RTK) and
attitude sensing.
1.9 Automotive Dead Reckoning
Automotive Dead Reckoning (ADR) is u-blox’ industry proven off-the-shelf Dead Reckoning solution for tier-one
automotive customers. u-blox’ ADR solution combines GPS and sensor digital data using a tightly coupled
Kalman filter. This improves position accuracy during periods of no or degraded GPS signal.
The NEO-6V provides ADR functionality over its software sensor interface. A variety of sensors (such as wheel
ticks and gyroscope) are supported, with the sensor data received via UBX messages from the application
processor. This allows for easy integration and a simple hardware interface, lowering costs. By using digital
sensor data available on the vehicle bus, hardware costs are minimized since no extra sensors are required for
Dead Reckoning functionality. ADR is designed for simple integration and easy configuration of different sensor
options (e.g. with or without gyroscope) and vehicle variants, and is completely self-calibrating.