Frequency Hopping Positioning Reference Signals Narrowband Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In enhanced Machine Type Communication (eMTC) environments, traditional positioning techniques face challenges in accurately determining the position of low-cost or low-complexity devices due to reduced bandwidth, particularly in receiving positioning reference signals (PRS) from base stations.
Innovation Solution
The described techniques involve a system where serving and neighboring base stations transmit PRS configurations, including hopping frequencies, periodicity, and duration, allowing user equipment (UE) to measure and report PRS transmissions, enabling accurate positioning despite limited bandwidth by using shared radio frequency spectra and coordinated frequency hopping patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If traditional positioning techniques are used in eMTC environments with reduced bandwidth, then device cost and complexity are reduced, but positioning accuracy deteriorates due to limited PRS transmission opportunities
Solution Approach 1:
The patent implements dynamic frequency hopping patterns for PRS transmissions, where base stations transmit positioning reference signals across multiple frequencies over time. This dynamic approach allows narrowband devices to receive PRS transmissions despite bandwidth limitations, as the system adapts the frequency allocation dynamically rather than using static frequency assignments. The UE can track positioning information across frequency hops, maintaining positioning accuracy while supporting cost-effective narrowband devices.
Solution Approach 2:
The patent extends positioning from a single frequency dimension to multiple frequency dimensions by implementing frequency hopping. Instead of being constrained to a single narrowband frequency, the system utilizes multiple frequency resources across different time instances. This dimensional expansion allows the system to overcome the bandwidth limitation of narrowband devices by distributing PRS transmissions across the frequency spectrum and having the UE aggregate measurements from multiple frequency hops.
2Productivity
If PRS transmissions are limited to predetermined time periods in narrowband systems, then system resource usage is optimized, but positioning reliability deteriorates due to reduced measurement opportunities
Solution Approach 1:
The patent implements periodic PRS transmissions with configured time periods and frequency hopping patterns. Base stations transmit PRS signals periodically across multiple frequencies, and the UE performs measurements at these periodic intervals. This periodic action ensures that positioning measurements are taken regularly while maintaining system resource efficiency, as the transmission schedule is predetermined and optimized for narrowband constraints.
Solution Approach 2:
The patent ensures continuous positioning capability by implementing frequency hopping that spans multiple time instances. Instead of having gaps in positioning measurements, the system continuously transmits PRS signals across different frequencies over time, allowing the UE to maintain continuous tracking of positioning information. This continuity compensates for the narrowband limitation by ensuring that positioning measurements are always available, just distributed across frequency and time dimensions.
3Device complexity
If narrowband devices operate in limited bandwidth regions, then device complexity is reduced, but the ability to detect and measure PRS from multiple base stations deteriorates
Solution Approach 1:
The patent employs dynamic frequency hopping patterns that allow PRS transmissions to occur across multiple frequencies sequentially. Narrowband devices with limited instantaneous bandwidth can still detect PRS from multiple base stations because the frequency hopping distributes transmissions across different time instances. The UE switches frequencies according to the hopping pattern, enabling it to capture PRS signals from multiple base stations despite having narrowband reception capability.
Solution Approach 2:
The system provides preliminary configuration information to the UE about the frequency hopping patterns and PRS transmission schedules of multiple base stations. This preliminary action enables the narrowband device to prepare and tune to the correct frequencies at the right times to detect PRS transmissions. By providing advance knowledge of the frequency allocation pattern, the system compensates for the device's limited bandwidth capability.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods, systems, and devices for wireless communication that support positioning techniques are described. One method may include receiving a positioning reference signal (PRS) configuration; receiving a plurality of PRS transmissions over a shared radio frequency spectrum from a plurality of base stations; and transmitting a measurement report of the PRS transmissions. The PRS transmissions may be received according to the PRS configuration. Another method may include receiving a discovery reference signal (DRS) transmission from a first base station; decoding a cell identifier of the first base station based on the DRS transmission; determining timing information of the first base station based on the DRS transmission; and transmitting a measurement report of the DRS transmission to a second base station.