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Global Positioning System (GPS)
RC3000A merges GPS satellite and network information to provide a high-availability
solution that offers industry-leading accuracy and performance. This solution performs
well, even in very challenging environment conditions where conventional GPS receivers
fail, and provides a platform to enable wireless operators to address both location-based
services and emergency mandates.
Technical specification:
Tracking sensitivity
-157dBm
Cold-start sensitivity
-144dBm
Accuracy (Open Sky)
<2m (CEP50)
TTFF (Open Sky)
Hot start <1s Cold start 35s (good signal)/100s (weak signal)
Receiver Type
16-channel, GPS L1 Frequency (1575.42MHz), C/A Code
Update rate
default 1 Hz
GPS data format
NMEA-0183
GPS Current consumption (WCDMA/GSM Sleep mode)
100mA (Total supply current)
GPS antenna
Passive/Active antenna
Note: Performance will vary depending on the environment, antenna type and signal conditions
and so on.
RC3000A supports both A-GPS and S-GPS, and then provides three operating modes: mobile-
assisted mode, mobile-based mode and standalone mode. A-GPS includes mobile-assisted and
mobile-based mode.
In mobile-assisted mode, when a request for position location is issued, available network
information is provided to the location server (e.g. Cell-ID) and assistance is requested from the
location server. The location server sends the assistance information to the handset. The
handset/mobile unit measures the GPS observables and provides the GPS measurements along
with available network data (that is appropriate for the given air interface technology) to the
location server. The location server then calculates the position location and returns results to
the requesting entity.
In mobile-based mode, the assistant data provided by the location server encompasses not only
the information required to assist the handset in measuring the satellite signals, but also the
information required to calculate the handset’s position. Therefore, rather than provide the GPS
measurements and available network data back to the location server, the mobile calculates the
location on the handset and passes the result to the requesting entity.
In standalone (autonomous) mode, the handset demodulates the data directly from the GPS
satellites. This mode has some reduced cold-start sensitivity, and a longer time to first fix as
