Apparatus, system and method of synchronization between Global Navigation Satellite System (GNSS) measurements and inertial measurements
Some demonstrative embodiments include apparatuses, devices, systems and methods of synchronizing time. For example, an apparatus may include a GNSS receiver to output GNSS measurements, and an output-timing signal including a plurality of pulses based on a clock of the GNSS receiver; an IMU to output inertial measurements, the IMU including a magnetometer to output magnetometer measurements; an antenna to emit an electromagnetic signal based on the output-timing signal, the electromagnetic signal to be measured by the magnetometer; and a processor to process the GNSS measurements and the inertial measurements, to detect in the magnetometer measurements one or more detected pulses of the output-timing signal, to determine a time delay between a clock of the IMU and the clock of the GNSS receiver based the detected pulses, and to adjust a time-base of the inertial measurements to a time-base of the GNSS measurements based on the time delay.
1. An apparatus of a mobile device, the apparatus comprising:
a Global Navigation Satellite System (GNSS) receiver to output GNSS measurements, and an output-timing signal comprising a plurality of pulses based on a clock of the GNSS receiver;
an Inertial Measurement Unit (IMU) configured to output inertial measurements, the IMU comprising a magnetometer configured to output magnetometer measurements;
an antenna to emit an electromagnetic signal based on the output-timing signal, the electromagnetic signal configured to be measured by the magnetometer; and
a processor to process the GNSS measurements and the inertial measurements, the processor to detect in the magnetometer measurements one or more detected pulses of the output-timing signal, to determine a time delay between a clock of the IMU and the clock of the GNSS receiver based the detected pulses, and to adjust a time-base of the inertial measurements to a time-base of the GNSS measurements based on the time delay.
2. The apparatus of claim 1 , wherein the output-timing signal comprises a One Pulse Per Second (1 PPS) output signal from the GNSS receiver.
3. The apparatus of claim 1 , wherein the output-timing signal of the GNSS receiver is Epoch-aligned.
4. The apparatus of claim 1 , wherein the processor is configured to determine the time delay based on a timing of the detected pulses.
5. The apparatus of claim 1 , wherein the processor is configured to determine the time delay based on a comparison between a timing of the one or more detected pulses and a timing of one or more of the pulses of the output-timing signal.
6. The apparatus of claim 1 , wherein the processor is configured to determine the time delay based on a comparison between a rising edge of a detected pulse and a beginning of a pulse of the output-timing signal.
7. The apparatus of claim 1 , wherein the IMU comprises at least one of a gyroscope to output gyroscope measurements or an accelerometer to output accelerometer measurements.
8. The apparatus of claim 1 , wherein the processor is configured to determine an estimated location of the mobile device based on the GNSS measurements and the inertial measurements.
9. The apparatus of claim 1 , wherein the antenna comprises a magnetic loop antenna.
10. An apparatus comprising logic and circuitry configured to cause a mobile device to:
process an output-timing signal from a Global Navigation Satellite System (GNSS) receiver of the mobile device, the output-timing signal comprising a plurality of pulses based on a clock of the GNSS receiver;
process inertial measurements from an Inertial Measurement Unit (IMU) of the mobile device, the inertial measurements comprising magnetometer measurements of a magnetometer of the IMU;
detect in the magnetometer measurements one or more detected pulses of the output-timing signal;
determine a time delay between a clock of the IMU and the clock of the GNSS receiver based on the detected pulses; and
adjust a time-base of the inertial measurements to a time-base of GNSS measurements from the GNSS receiver based on the time delay.
11. The apparatus of claim 10 , wherein the output-timing signal comprises a One Pulse Per Second (1 PPS) output signal from the GNSS receiver.
12. The apparatus of claim 10 configured to determine the time delay based on a timing of the detected pulses.
13. The apparatus of claim 10 configured to determine the time delay based on a comparison between a timing of the one or more detected pulses and a timing of one or more of the pulses of the output-timing signal.
14. The apparatus of claim 10 configured to determine the time delay based on a comparison between a rising edge of a detected pulse and a beginning of a pulse of the output-timing signal.
15. The apparatus of claim 10 , wherein the one or more inertial measurements comprise at least one of gyroscope measurements or accelerometer measurements.
16. The apparatus of claim 10 configured to cause the mobile device to determine an estimated location of the mobile device based on the GNSS measurements and the inertial measurements.
17. The apparatus of claim 10 comprising a memory and a processor.
18. A product comprising one or more tangible computer-readable non-transitory storage media comprising computer-executable instructions operable to, when executed by at least one processor, enable the at least one processor to cause a mobile device to:
process an output-timing signal from a Global Navigation Satellite System (GNSS) receiver of the mobile device, the output-timing signal comprising a plurality of pulses based on a clock of the GNSS receiver;
process inertial measurements from an Inertial Measurement Unit (IMU) of the mobile device, the inertial measurements comprising magnetometer measurements of a magnetometer of the IMU;
detect in the magnetometer measurements one or more detected pulses of the output-timing signal;
determine a time delay between a clock of the IMU and the clock of the GNSS receiver based on the detected pulses; and
adjust a time-base of the inertial measurements to a time-base of GNSS measurements from the GNSS receiver based on the time delay.
19. The product of claim 18 , wherein the output-timing signal comprises a One Pulse Per Second (1 PPS) output signal from the GNSS receiver.
20. The product of claim 18 , wherein the instructions, when executed, cause the mobile device to determine the time delay based on a timing of the detected pulses.
21. The product of claim 18 , wherein the instructions, when executed, cause the mobile device to determine the time delay based on a comparison between a timing of the one or more detected pulses and a timing of one or more of the pulses of the output-timing signal.
22. The product of claim 18 , wherein the instructions, when executed, cause the mobile device to determine the time delay based on a comparison between a rising edge of a detected pulse and a beginning of a pulse of the output-timing signal.
23. The product of claim 18 , wherein the one or more inertial measurements comprise at least one of gyroscope measurements or accelerometer measurements.
24. An apparatus of a mobile device, the apparatus comprising:
means for processing an output-timing signal from a Global Navigation Satellite System (GNSS) receiver of the mobile device, the output-timing signal comprising a plurality of pulses based on a clock of the GNSS receiver;
means for processing inertial measurements from an Inertial Measurement Unit (IMU) of the mobile device, the inertial measurements comprising magnetometer measurements of a magnetometer of the IMU;
means for detecting in the magnetometer measurements one or more detected pulses of the output-timing signal;
means for determining a time delay between a clock of the IMU and the clock of the GNSS receiver based on the detected pulses; and
means for adjusting a time-base of the inertial measurements to a time-base of GNSS measurements from the GNSS receiver based on the time delay.
25. The apparatus of claim 24 comprising means for determining the time delay based on a timing of the detected pulses.