UWB Receiver Phase Estimation for Pulse Arrival Time

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current UWB receivers face challenges in accurately determining the arrival time of UWB pulses without synchronization references and ambiguity in time hopping codes, especially with short pulses requiring high correlation rates.

Innovation Solution

A method involving correlation of received UWB signals with an orthogonal basis of quadrature signals to estimate the phase, allowing for precise determination of pulse arrival time without sliding correlations, using a phase estimator to calculate the arrival time from projection values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If sliding correlation is performed to determine pulse arrival time, then measurement precision is improved, but device complexity and computational complexity increase significantly

Engineering Contradiction:

Improvepulse arrival time determination precisionVSAvoidreceiver complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The time window is divided into multiple non-overlapping sub-windows, and the correlation operation is segmented to be performed independently in each sub-window. This reduces the computational burden of full-window sliding correlation while maintaining arrival time detection capability through phase information extraction from each segment.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The mechanical sliding correlation process is replaced with a phase estimation approach using quadrature correlation. Instead of physically sliding the correlation window and computing full correlations, the method uses fixed quadrature correlators to extract phase information, which is then converted to arrival time estimates, significantly reducing computational complexity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If sliding correlation is performed to determine pulse arrival time, then measurement precision is improved, but processing time increases

Engineering Contradiction:

Improvepulse arrival time determination precisionVSAvoidprocessing time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Quadrature correlators continuously process the received signal to extract phase information in advance, before a complete sliding correlation would be needed. The phase estimates from multiple sub-windows are then combined to determine the final arrival time, enabling faster processing than traditional sliding correlation.

Inventive Principle:

Principle #10Preliminary action

3Device complexity

If quadrature correlation is used to estimate phase, then device complexity is reduced, but measurement precision may be affected by ambiguity

Engineering Contradiction:

Improvereceiver complexityVSAvoidarrival time estimation unambiguity

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

Phase estimates from multiple sub-windows are merged using a weighted combination approach. The weights are determined based on the signal energy or reliability in each sub-window, allowing the system to combine information from multiple segments to produce an unambiguous arrival time estimate that overcomes the limitations of individual quadrature correlation measurements.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The system uses feedback from the phase estimation process to resolve ambiguities. By comparing phase differences across multiple sub-windows and using the known pulse repetition structure, the system can detect and correct phase wrapping ambiguities, ensuring accurate arrival time determination despite the simplified quadrature correlation approach.

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP2909945B1Method for the determination of the time of arrival of an UWB pulse and corresponding receiver

Publication Date: 2016.08.17 COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES

Figure 1A~1B
Figure 2
Figure 3A

AI summary

The invention relates to a method for determining the arrival time of a UWB pulse at a receiver. When the pulse is modulated at an RF frequency, the receiver comprises: a quadrature demodulator (330); a first correlation stage (351, 352) for correlating the signal in phase with the first and second signals of an orthogonal base over a time window and a second correlation stage (353, 354) for correlating the signal in quadrature with the first and second signals of the orthogonal base over the same window; a phase estimator (360) that estimates the phase of the signal received in the orthogonal base on the basis of the correlation results from the first and/or second correlation stage(s); and computing means (370) for determining the arrival time on the basis of the estimated phase.