Location based services Applications and positioning technologies and methods

Location Based Services (LBS) leverage the geographical position of a device to provide information and to offer entertainment or security services. These services have become an integral part of our daily lives due to advancement in GPS/GNSS, mobile phone devices and wireless communication. This article explores the various applications, advantages and disadvantages of LBS system.

Applications of Location Based Services

Following are the location based services applications or use cases.
1. Navigation and Mapping:
• These applications offer real-time navigation, route planning, and traffic updates, helping users reach their destinations efficiently. Examples : Google Maps and Waze.
• Public Transportation Apps provide real-time information on public transport schedules routes and delays. Examples : Moovit and Citymapper

2. Social Networking:
• Facebook and Instagram: Users can tag their locations in posts and photos which enhances social interactions and sharing experiences.
• Foursquare and Swarm: These apps allow users to check in at various locations, and help in discovering new places and to earn rewards.

3. Retail and Advertising:
• Targeted Advertising: Businesses use LBS to send personalized promotions and advertisements to users based on their location.
• Store Locator Services: Retailers provide information about the nearest store locations, product availability, and special offers.

4. Emergency & Disaster services:
Emergency responders can quickly locate individuals in distress based on their mobile device's GPS coordinates. Moreover, authorities can use LBS for efficient disaster response and management.

5. Healthcare:
• LBS enables healthcare providers to monitor patients' health remotely, especially for those with chronic conditions.
• Fitness applications like Strava and MyFitnessPal track users' activities and routes.

6. Tourism and Travel:
• Apps like TripAdvisor and Yelp provide recommendations and reviews for nearby attractions, restaurants and hotels.
LBS enhances Augmented Reality (AR) applications, offering interactive and immersive experiences for tourists.

Technologies and Methods Used for Positioning in Location Based Services

The technologies such as wifi, cellular, BLE, RFID, UWB and satellites are used for positioning calculation. The common methods or techniques used include triangulation, trilateration, multilateration, proximity, Dead Reckoning, RF fingerprinting etc.

1. Satellite based positioning (GPS, GNSS)

There are numerous navigation systems which uses satellites to provide location and time information anywhere on the Earth. These include GPS, GNSS, GALILEO, BeiDou, IRNSS etc.

The figure-1 depicts GNSS based positioning estimation modules. It uses pseudo-ranges and ToAs and least square algorithm to determine location, time and velocity of the device. Moreover data fusion module in GNSS utilizes location related data from other sources such as wifi routers and cellular towers to estimate more accurate and precise location of the device. The figure-2 depicts GPS based navigation system.

2. Wi-Fi Positioning System (WPS)

The WiFi positioning system uses nearby Wi-Fi routers or Access Points (APs) to triangulate the position of a device. This technique uses the signal strength from multiple WiFi APs to estimate the device's location. This method is often used in indoor navigation where GPS signals are weak or unavailable.

3. Cellular Network Triangulation

This method determines location based on the relative signal strength of nearby cell towers. It is used by mobile carriers to provide location data in areas with good cellular coverage. There are two techniques as mentioned below.
1. Cell ID based : Identifies the location based on the ID of the connected cell tower.
2. Cellular Triangulation based : Estimates the position by measuring the signal strength and time delay from multiple cell towers.

4. Bluetooth Low Energy (BLE)

BLE technology uses low-power Bluetooth beacons to provide location information. It is commonly used in retail environments for proximity marketing and indoor navigation. Following are the two methods used in BLE.
1. Devices use the proximity to Bluetooth beacons to determine their location, often used indoors.
2. Bluetooth Angle of Arrival (AoA) and Angle of Departure (AoD) determines the direction of the Bluetooth signal for more precise positioning.

5. RFID (Radio-Frequency Identification)

RFID uses electromagnetic fields to automatically identify and track tags attached to objects. It is used in inventory management, asset tracking and access control systems. There are two types of tags based on which position is detected.
1. Passive RFID: Uses electromagnetic fields to read tags attached to objects, useful for inventory tracking.
2. Active RFID: Uses battery powered tags that emit signals, providing more precise location data over greater distances.

6. Ultra-Wideband (UWB)

UWB is a short range wireless communication protocol that provides highly accurate location data. It is used in precision tracking applications, such as locating items within a few centimeters. There are two techniques in UWB technology to estimate location of the device under observation.
1. Time of Flight (ToF): Measures the time it takes for a signal to travel between the device and UWB anchors to calculate distance.
2. Time Difference of Arrival (TDoA): Uses the difference in arrival times of the signal at multiple anchors to determine the location.

7. Hybrid Positioning Systems

It uses multiple positioning methods simultaneously to improve accuracy and reliability. It uses data from GPS, WiFi, Bluetooth and cellular technologies. This is especially helpful in challenging environments.

8. Positioning Sensors or Inertial Measurement Units (IMUs)

IMUs use accelerometers, gyroscopes and magnetometers to estimate the device's position and movement. Enhances indoor navigation and provides more accurate tracking in environments where GPS is unreliable. The common techniques which employ positioning sensors Dead Reckoning and Pedestrian Dead Reckoning.

Advantages of Location Based Services

Following are the benefits or advantages of LBS system.
1. LBS offers greater amount of convenience to its users as it simplifies daily tasks such as navigation, finding nearby services and receiving personalized recommendations.
2. Users receive real time and up to date information on traffic, weather, events and offers based on their current location.
3. Emergency services can locate individuals quickly, improving response times and potentially saving lives. Hence LBS offers enhanced safety.
4. Businesses can offer personalized services and promotions, enhancing customer satisfaction, loyalty and increased sells.
5. LBS streamline operations in various sectors, such as logistics, healthcare and public transportation, leading to cost savings, improved service delivery and increased efficiency.

Disadvantages of Location Based Services

Following are the drawbacks or disadvantages of LBS system.
1. The continuous tracking of users' locations raises significant privacy issues. Unauthorized access to location data can lead to misuse or breaches.
2. Constant use of location tracking technologies and techniques drain the battery life of mobile devices quickly.
3. LBS rely on a stable internet connection, which may not be available in remote or underserved areas. Hence users in such areas are deprived of Location Based Services.
4. Location data can be exploited by malicious persons for stalking, theft or other criminal activities.
5. Inaccurate or outdated location data can lead to incorrect information or directions, causing inconvenience or potential harm.

Conclusion

Location Based Services have transformed the way we navigate, socialize, shop and manage emergencies. While they offer numerous benefits, it is crucial to address the associated privacy, security and accuracy concerns to ensure that users can enjoy these services safely and effectively. As technology continues to advance, the scope and capabilities of LBS are likely to expand, further integrating them into our daily lives.