Differential Aiding Waas/Egnos; Navigation Modes; Core Processor Performance; Dynamic Constraints - Navman Jupiter 110 Manual

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If the ephemeris data become invalid, the RTC has the ability to self activate and refresh the
data, thus keeping the restart TTFF very short.
For further information about TricklePower refer to the Low Power Operating Modes
application note (LA000513).

3.5 Differential aiding WAAS/EGNOS

The Jupiter 110 is capable of receiving WAAS and EGNOS differential corrections. WAAS/
EGNOS improves horizontal position accuracy to <6 m 2 dRMS by correcting GPS signal errors
caused by ionospheric disturbances, timing and satellite orbit errors.

3.6 Navigation modes

The Jupiter 110 supports 3D (three-dimensional) and 2D (two-dimensional) modes of navigation.
the receiver defaults to 3D navigation when at least four GPS satellites are
3D navigation:
being tracked. In 3D navigation, the receiver computes latitude, longitude, altitude, and time
information from satellite measurements.
when less than four GPS satellite signals are available, or when a fixed altitude
2D navigation:
value can be used to produce an acceptable navigation solution, the receiver will enter 2D
navigation using a fixed value of altitude determined by the host. Forced operation in 2D mode
can be commanded by the host.
In 2D navigation, the navigational accuracy is primarily determined by the relationship of the
fixed altitude value to the true altitude of the antenna. If the fixed value is correct, the specified
horizontal accuracies apply. Otherwise, the horizontal accuracies will degrade as a function of
the error in the fixed altitude.

3.7 Core processor performance

The standard Jupiter 110 with GSW2 software runs at a CPU clock speed of 12.28 MHz. Using
XTrac software (Jupiter 110S and 110RS), the clock speed increases to 24.5 MHz. An SDK
(Software Development Kit) is available from SiRF to customise the Jupiter 110 firmware. Using
the SiRF SDK the clock speed can be increased up to 49 MHz.
The processor performance of the Jupiter 110 is shown in Table 3-2.
Parameter
typical performance
peak performance

Table 3-2: Jupiter 110 processor performance

3.8 Dynamic constraints

The Jupiter 110 is programmed to lose track if any of the following limits is exceeded:
Velocity: 500 m/s max
Acceleration: 4 G (39.2 m/s/s) max
Altitude: 18 000 m

3.9 Position and velocity accuracy

Position and velocity accuracy of the Jupiter 110 are shown in Table 3-3, assuming full accuracy
C/A code. These values are the same in normal operation and when TricklePower is active.
horizontal (2 dRMS)
velocity 3D (2 sigma)
LA000504D © 2006 Navman New Zealand. All rights reserved. Proprietary information and specifications subject to change without notice.
J110/J110R
2-3 MIPS
6-7 MIPS
Parameter
horizontal CEP
vertical VEP
3D SEP

Table 3-3: Position and velocity accuracy

J110S/J110RS
4-5 MIPS
8-9 MIPS
J110/J110R J110S/J110RS
2.2 m 3.0 m
5.5 m 6.0 m
2.5 m 5.0 m
5.0 m 5.0 m
0.1 m/s 0.1 m/s