S-GPS

Simultaneous GPS (S-GPS) is a method to allow a GPS reception and CDMA communications to operate simultaneously in a mobile phone.

Ordinarily, cellular geolocation and a built-in GPS receiver is used to determine the location of an E911 call made from CDMA phones. By using a time-multiplexed scheme called TM-GPS, the reception of the telephone call and the GPS signal are alternated one after the other, requiring only one radio receiver.

Simultaneous GPS allows a cellphone to receive both GPS and voice data at the same time, which improves sensitivity and allows service providers to offer location-based services.^[1] The use of two radios with a single antenna imparts new design challenges, such as leakage of the voice transmitter signal into the GPS receiver circuitry.^[2] The commercial availability of S-GPS chipsets from manufacturers such as Qualcomm, has led to adoption of the method in newer handsets.^[3]

References

^ Milette, Greg; Stroud, Adam (2012-05-18). Professional Android Sensor Programming. John Wiley & Sons. p. 6. ISBN 9781118240458.
^ Xu, Y.; Wang, K.; Pals, T.; Hadjichristos, A.; Sahota, K.; Persico, C. (1 September 2007). "A Low-IF CMOS Simultaneous GPS Receiver Integrated in a Multimode Transceiver". 2007 IEEE Custom Integrated Circuits Conference. pp. 107–110. doi:10.1109/CICC.2007.4405692. ISBN 978-1-4244-0786-6. S2CID 16237573.
^ "Improving S-GPS sensitivity". Avago Technologies. Archived from the original on 2012-07-22.