GPS receiver

The GPS receiver supports GPS L1 C/A reception. Operation is time multiplexed with LTE modem, and it is possible to obtain the GPS 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 receiver is accessible to user through the GPS API.

Note: For details regarding the modem API, please refer to nRF Connect SDK document and nRF91 AT Commands, Command Reference Guide document.

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

Table below summarises GPS receiver performance parameters.

Table 1. 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, open sky, typical 36 s
TTFF, hot Acquisition time (TTFF), hot start, open sky, typical 1.3 s
Accuracy, periodic Positioning accuracy (CEP50), periodic tracking 5 m
Accuracy, continuous Positioning accuracy (CEP50), continuous tracking 3 m