GPS receiver

The GPS receiver supports GPS L1 C/A and QZSS L1 C/A reception. Operation is time multiplexed with LTE modem, and it is possible to use the GPS and QZSS receiver to obtain position either while the LTE is in RRC Idle mode or power saving mode (PSM), or when the LTE modem is completely deactivated.

The application processor is the master in the system and responsible for starting and stopping of the GPS receiver. GPS can be run standalone or concurrently with QZSS. GPS and QZSS receiver configuration is accessible to user through the GNSS interface API.

Note: For details regarding the GNSS API, please refer to nRF Connect SDK API documentation.

Key features of the GPS receiver are:

Note: There must be minumum 27dB attenuation to out of band power to avoid blocking high power RF signals to GPS receiver input. This can be achieved for example by a SAW filter at the output of the external LNA.

Electrical specification

Summary of GPS receiver performance parameters.

Table 1. Common typical conditions
Condition Value
Environment Open sky
Temperature 25 °C
GPS sleep clock source TCXO

Note: Local and temporal conditions may lead to considerable variation in TTFF, positioning accuracy, 1PPS signal accuracy.

Table 2. GPS electrical specification
Symbol Description Value Unit
Sensitivity, cold Acquisition sensitivity, cold start -145.5 dBm
Sensitivity, hot Acquisition sensitivity, hot start -147 dBm
Sensitivity, tracking Tracking sensitivity -155 dBm
TTFF, cold Acquisition time (time to first fix (TTFF)), cold start 36 s
TTFF, hot Acquisition time (TTFF), hot start 1.3 s
Accuracy, 2D, periodic Positioning accuracy (CEP50), periodic tracking 5 m
Accuracy, 2D, continuous Positioning accuracy (CEP50), continuous tracking 3 m
1PPS accuracy 1PPS signal accuracy, continous tracking ±40 ns