Chirp-Signal Positioning with LOS Selection for Multipath Environments
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Indoor positioning systems face accuracy deterioration in multipath environments due to overlapping signals from reflections and multiple reflections, and increasing the number of anchors for better precision leads to higher costs.
Innovation Solution
A positioning system using chirp signals transmitted by multiple antennas to select and demodulate line-of-sight signals, calculating departure angles to determine the receiver's position accurately in a multipath environment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of anchors is increased to improve positioning precision, then positioning accuracy is improved, but system cost increases
Solution Approach 1:
The patent replaces traditional mechanical/traditional wireless positioning methods with chirp signal-based electromagnetic wave propagation modeling. By using the phase difference of chirp signals received from multiple anchors and calculating departure angles through trigonometric relationships, the system achieves high positioning accuracy without requiring complex multi-anchor infrastructure, thus reducing system cost while maintaining precision
Solution Approach 2:
The patent changes the signal parameter from conventional wireless signals to chirp signals with specific frequency-time characteristics. By utilizing the linear frequency modulation property of chirp signals and calculating phase differences across multiple reception time points, the system extracts accurate geometric information about signal paths, enabling precise positioning with fewer anchors and lower system complexity
2Ease of manufacture
If traditional positioning methods are used in multipath environments, then system implementation is simple, but positioning accuracy deteriorates due to overlapping reflected signals
Solution Approach 1:
The patent extracts and isolates the line-of-sight signal component from the complex multipath signal environment. By using chirp signal correlation techniques and analyzing phase differences at specific time delays, the system identifies and separates the direct signal path from reflected paths, effectively removing the harmful multipath components while maintaining implementation simplicity through straightforward signal processing algorithms
Solution Approach 2:
The patent introduces chirp signals as an intermediary carrier that enables accurate positioning in multipath environments. The chirp signal's unique time-frequency characteristics serve as a mediator that allows the receiver to distinguish between direct and reflected paths through correlation analysis, transforming the difficult problem of multipath separation into a manageable signal processing task while maintaining system simplicity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances positioning accuracy by selecting and demodulating line-of-sight signals, allowing precise determination of the receiver's position using at least two transmitters.
Implementation Method 1
a first wireless transmitter sequentially drives a plurality of transmit antennas arranged at regular intervals according to an arrangement order thereof to transmit the same first chirp signals
Implementation Method 2
an IQ demodulation unit configured to IQ-demodulate a signal selected as the LOS signal
Implementation Method 3
a calculation unit configured to calculate an angular position of a wireless transmitter transmitting the signal from a phase value of a ratio of an IQ signal demodulated by the IQ demodulation unit
Data Source
AI summary
A radio frequency signal transmitted from a transmit antenna is received to measure a departure angle, which is an angular position from the transmit antenna as viewed from a receive antenna, and a position of a wireless receiver is estimated using a position of a wireless transmitter, whose position is known, and a departure angle from this transmitter.