Alternative localization approach for mobile phones without GPS

Abstract

Location is a primary indicator of context and forms the core basis of several context-aware applications. Most common way of getting location information is to use specialized hardware like GPS. However, GPS is expensive and is available only on high-end phones restricting its use to a smaller population in developing countries. Further, GPS also consumes a lot of battery power during its operation, thereby making it infeasible to run for longer durations with limited mobile phone battery. An alternative to GPS-based localization is GSM-based localization that is more suitable for developing countries due to much lower power consumption and ability to run even on low-end phones. Currently available, network-operator independent, GSM-based solutions require building perceptual map of cell towers in a city using war-driving.In this paper, we present a novel low cost GSM-based solution based on Cell Broadcast (CBS) Messages. Location accuracy in our approach does not depend on building extensive cell ID database, typically built using war-driving. We present empirical studies (performed in the sub-city of Dwarka, New Delhi, India) comparing location accuracy of our approach with other GSM-based localization scheme that uses one of the most extensive open source database of cell IDs. We also compare power consumption of our proposed solution with GPS-based localization leading to energy-accuracy tradeoff that can be further exploited for a hybrid solution.

Location Privacy Leakage through Sensory Data

“…Attackers not only want to infer privacy information, but also try to do it efficiently [39]. In order to save energy, Yadav et al [21] proposed their low cost GSM-based localization method based on Cell Broadcast Messages and war-driving. To tackle the problem that the Maximum Likelihood estimator for received signal strength (RSS) based localization is nonconvex, Ouyang et al [40] proposed an Semidefinite Programming (SDP) relaxation technique to solve this problem.…”

“…Such a strategy seems to provide satisfiable location privacy. However, many works have pointed out that, without accessing GPS data, Apps can still infer private information, such as input on touch-screen [16] and motion status [17], through the data collected by general embedded sensors in mobile devices [18][19][20][21][22][23][24][25][26][27]. Unfortunately, few works try to utilize built-in sensors like accelerometer, magnetometer, gyroscope, and so on to do localization.…”

Virtual Detection Zone in smart phone, with CCTV, and Twitter as part of an Integrated ITS

“…Mobile phones can be used as traffic sensor, when location data of the user can be determined via an application (agent), either by using US Global Positioning System (GPS) or from other navigation satellites such as: Russia's Glonass and Europe's Galileo [21] [22] [23] [24] or from non GPS enabled phones, using Cell ID [25] or Internet based devices [26]- [27]. It is noted also that as technology progressed, the corresponding speed difference has become smaller or is considered reasonably accurate, i.e.…”