Ambient Backscatter Precoder Phase Selection for Signal Decoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ambient backscatter communication systems face challenges in achieving effective data decoding due to the interference from interfering signals, which complicates the implementation and increases energy costs, especially in complex propagation environments like those with walls and trees, where the power threshold for decoding is hard to reach.
Innovation Solution
A method involving a focusing precoder with phase shifting to optimize the phase difference between backscattered and interfering signals, allowing the receiving device to combine these signals for maximum electromagnetic power, thereby simplifying the communication process and reducing complexity and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the receiving device carries out processing operations to cancel the interfering signal, then the decoding accuracy is improved, but the device complexity and implementation cost increase
Solution Approach 1:
The patent converts the harmful interfering signal into a beneficial component by adjusting the phase of the backscattered signal to align constructively with the interfering signal. This transforms the interference from a detrimental factor into a useful signal component that enhances the total received power, eliminating the need for complex cancellation processing while improving decoding accuracy
Solution Approach 2:
The patent changes the phase parameter of the backscattered signal dynamically to optimize the constructive combination with the interfering signal. By adjusting the phase shift applied to the backscattered signal, the system maximizes the total received power at the receiver, thereby improving decoding performance without increasing device complexity
2Measurement precision
If the receiving device carries out processing operations to cancel the interfering signal, then the decoding accuracy is improved, but the implementation cost increases
Solution Approach 1:
The patent converts the harmful interfering signal into a beneficial component by adjusting the phase of the backscattered signal to align constructively with the interfering signal. This transforms the interference from a detrimental factor into a useful signal component that enhances the total received power, eliminating the need for complex cancellation processing while improving decoding accuracy
3Loss of information
If the transmitter device backscatters the ambient signal, then data transmission is achieved, but the electromagnetic power received may not reach the decoding threshold due to interference
Solution Approach 1:
The patent changes the phase parameter of the backscattered signal dynamically to optimize the constructive combination with the interfering signal. By adjusting the phase shift applied to the backscattered signal, the system maximizes the total received power at the receiver, thereby improving decoding performance without increasing device complexity
Solution Approach 2:
The patent implements a feedback mechanism where the receiver measures the total received power and feeds back information to the transmitter about the current signal conditions. Based on this feedback, the transmitter adjusts the phase of subsequent backscattered signals to maintain constructive interference and ensure the received power remains above the decoding threshold
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
This approach enhances the decoding of data transmitted via backscattered signals by maximizing the electromagnetic power received, improving communication efficiency and reducing the complexity and cost of implementation in ambient backscatter systems.
Implementation Method 1
a step of phase shifting, by the source, of one of the components of the precoder P according to said value Φi
Implementation Method 2
a signal coming directly from the source called interfering signal and resulting from multiple reflections/diffractions of waves
Implementation Method 3
the backscattering of an ambient signal is carried out between at least one transmitting device and at least one receiving device
Implementation Method 4
the transmitter device reflects the ambient signal towards the receiver device
Implementation Method 5
a signal coming directly from the source called interfering signal and resulting from multiple reflections/diffractions of waves
Data Source
Figure 1~5
Figure 3
Figure 4
AI summary
The invention concerns a selection method by an ambient backscattering system (10) comprising a source (SO), as well as transmitter (D_TX) and receiver (D_RX) devices, the source being associated with a precoder P for focusing signals towards said devices. The method further comprises, for a plurality of values Φ_1, …, Φ_N: - a phase shifting (E20), by the source, of the precoder P depending on said value Φ_i, so as to obtain a precoder Q_i, - an emission (E30), by the source, by means of the precoder Q_i, - an acquisition (E40), by the receiver device, of power measurements during non-backscattering and backscattering states, - a determination (E50), by the receiver device, of a value D1_i representative of a power difference between the measurements. The method also comprises a selection (E60), by the receiver device, of a maximum value among the values D1_1, …, D1_N.