When we think of locating ourselves in the world or navigating to our destinations, satellite-based technologies like the global positioning system (GPS) readily come to mind. With a constellation of satellites covering the globe to help users resolve their location, GPS was a major improvement over earlier positioning technologies including closest cell tower and OmniTRACS for fleet management. We now have multiple satellite constellations to complement GPS. Smartphones and other compact positioning devices can use a combination of global navigation satellite systems (GNSS) like GPS, GLONASS, Beidou, and Galileo, and regional navigation satellite systems (RNSS) like QZSS and NavIC to provide meter-level precision.
While satellite-based positioning works very well when there’s clear line of sight to multiple satellites, accurate positioning in challenging radio environments needs the support of other technologies. Urban canyons with tall buildings in the vicinity of a device can block line of sight to positioning satellites and generate multiple reflections of their signals, or multipath, to cause large errors in the calculated position. Satellite-based positioning may only work in a narrow periphery of indoor spaces if signals from enough satellites manage to penetrate the walls or windows in the vicinity of the device. Cellular networks, sensors, local or personal area wireless technologies, and even AI are complementary technologies which can help provide more robust and seamless location awareness in such challenging environments.
Cellular positioning complements other positioning technologies for reliable precision.
Precise positioning benefits a broad range of use cases and devices
Checking how long a taxi, ride share, or courier truck will take to reach us, locating someone in any emergency, or navigating to a new destination are just some of the use cases of positioning technology we’re familiar with. 5G brings a new dimension of location awareness to the IoT with precise and robust positioning and benefit many more industrial and personal use cases like:
- Navigating indoors in shopping malls, hospitals, or mines
- Tracking drones robustly beyond visual line of sight (BVLOS)
- Having emergency response personnel reach emergencies quicker with more precise horizontal and vertical location information
- Being alerted when children or pets have left safe areas like school campuses or home perimeters, with geofencing
- Having rideshare services and taxis reach the right side of the road in urban canyons
- Tracking fleet vehicles accurately throughout their routes for better logistics
- Getting contextually relevant information for richer XR experiences and user insights, or
- Tracking assets in a warehouse, or automated guided vehicles (AGV) and autonomous mobile robots (AMR) on the factory floor
Precise positioning can benefit a diverse set of use cases.
With next-level 5G connectivity, precise positioning, and AI, Qualcomm envisions a wireless innovation platform which leverages on-device capabilities and analytics to create the Connected Intelligent Edge. The connected intelligent edge will grow stronger with smarter, more capable devices, which cooperate to bring new values and even better user experiences.
5G innovations for precise positioning
5G breaks technology barriers with key innovations for precise positioning in the 3GPP Release 16 standard, with enhancements due in Release 17 and in 5G Advanced. The wider bandwidths in 5G allow for finer timing resolutions. Time resolution is further improved by integrating methods for measuring, reporting, and compensating for processing delays into the radio protocol. The large number of antenna elements in massive MIMO, for mid-bands and mmWave, generate narrower radio beams which allow for finer angular resolution.
5G leverages time of flight and angular resolution to bring multiple positioning techniques for different deployment scenarios and use-cases. 5G mmWave supports highly precise positioning in the vertical and horizontal dimensions, with the narrower beam and wider bandwidth in mmWave frequencies lending to high precision in angle and timing. Joint processing of beam direction and estimated time of flight also helps mitigate the effects of multipath and improves positioning precision in urban canyons.
5G brings multiple positioning techniques for different deployment scenarios and use-cases.
Leading research for the road ahead
At Qualcomm Technologies, they have been advancing the state of the art in 5G positioning research for indoor and outdoor environments. At MWC 2021 in Barcelona, they demonstrated industrial precise positioning with 5G using uplink TDOA and sensor fusion to help automated guided vehicles (AGV) navigate industrial indoor environments with centimeter-level precision. They also showed the joint use of round-trip time (RTT) and angle of arrival (AoA) positioning techniques for single-cell based positioning, with meter-level accuracy for robust positioning in most practical outdoor deployments.
As Qualcomm looks to 3GPP Release 18 and 5G Advanced, they are exploring the flexibility 5G sidelink brings to positioning in different operational scenarios and with multiple spectrum options, including unlicensed spectrum. With the joint use of the 5G air interface and 5G sidelink, cooperative positioning methods can help improve the quality of positioning for a group of devices either entirely within coverage of a 5G cell or in partial coverage. When devices are out of coverage of a 5G cell, 5G sidelink can still help determine the distance between devices with ranging. While 5G sidelink provides mechanisms to introduce more nodes to transmit and receive positioning signals for improved positioning accuracy, AI/ML can be used and combined to further enhance position precision, especially in the presence of heavy non-line-of-sight (NLoS) scenarios, where detecting the first arrival path (FAP) can be challenging.
Looking further ahead, Qualcomm is excited about using the 5G air interface, including 5G sidelink, and AI/ML for cooperative sensing, to locate passive device-free objects. They could then use a joint communication and positioning/sensing technology platform to make navigation and XR experiences safer, for example, by locating obstructions in the vicinity. In addition, the information obtained from positioning/sensing can be further used to enhance communication. For example, we can switch to a different antenna beam, a different cell, or enable joint transmission and reception across multiple nodes to combat signal degradation due to obstructions. This would help deliver quality of service (QoS) requirements such as low latency and high reliability for more demanding connectivity use cases.