RSR GNSS Transcoder™ User Manual
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© 2017 Jackson Labs Technologies, Inc.
RAND - Random noise centered around 1575.42 MHz
Normally the output tone should be set to OFF to enable GPS RF signals.
The following command is an example showing how to configure the RSR GNSS Transcoder™ as a
CW jammer for mixing with another simulated or live-sky GPS signal:
OUTput:TEST TONE
Please note that transmissions in the GPS L1 band are regulated by government decree and that test
tone and GPS L1 RF output from the RSR GNSS Transcoder™ should not be transmitted from a
radiating antenna without permission from the FCC or other local regulating organization.
3.8.11 Configuring the simulated Time and Date
When operating in Simulation mode, the system can be configured to start the simulation using a
fixed specified time. The module can also use continuous time as provided by a reference input PVT
source. When using a fixed start time with repeated simulations, the target GPS receiver may require
a manual reset or cold-start to recognized the correct simulated time, and to properly receive the GPS
signals. This may happen because the target receiver does not expect the GPS time to jump
backwards between simulation runs. Cell-phone GPS receivers are notorious for knowing the current
UTC time and refusing to receive a time/date in the past or further out in the future without a
complete cold-start of the receiver. Using the continuous time sentences from a PVT source reduces
the need to cold-start the target receiver as the simulation will accurately transmit UTC time/date to
the target receiver, and thus fulfill any assumptions the target receiver would have about the current
time/date.
The simulation time mode is set with the SIMulation:TIME:MODE <ASSIGNed | CONTinuous>
command as detailed in Section
.
When using the ASSIGNed mode, the unit uses the time and date specified in the commands:
SIMulation:TIME:START:TIME
SIMulation:TIME:START:DATE
Assigning a date and time for the simulation is useful in simulating future leap-seconds, future GPS
week 1023 roll-over events, or any type of date/time anomaly in the target GPS receiver.
3.8.12 Simulating Leap Second Event
The UTC correction parameters that define the current and future leap second offset as well as
fractional second offsets between GPS and UTC time are configured with the SIM:TIME:UTC...
commands as detailed in Section
and later. The parameters that need to be set to simulate a
leap second event are the start time and date as described in Section
, and the
IS-GPS-200-defined UTC parameters DELTATLS, WNLSF, DN and DELTATLSF. The parameter
DELTATLS is the current number of seconds difference between UTC and GPS time. WNLSF is the
week number of the leap second event and DN is the day number (1 through 7) of the event. The
actual leap second event for positive leap seconds occurs immediately after 23:59:59 on the day
defined by WNLSF and DN. Finally, DELTATLSF is the final UTC offset in seconds after the leap
second event.
The RSR GNSS Transcoder™ also provides a simplified method of setting the UTC correction
parameters with the SIM:TIME:LEAP... commands. The SIM:TIME:LEAP:ACCumulated
Summary of Contents for RSR GNSS Transcoder
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