Adjustable Receiver Impedance for Interference-Resistant Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing RFID systems face challenges in detecting receivers due to interference, electromagnetic field minima, and simultaneous responses, leading to checkout errors and inefficiencies in item identification.
Innovation Solution
A detection system utilizing a global antenna and adjustable receivers with modifiable impedance, transitioning between detection and cooperation modes to enhance receiver detection by altering impedance configurations, optimizing the electromagnetic field for improved detection of multiple receivers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple receivers are placed next to each other in a cash register tray, then the system can detect more items simultaneously, but interference and electromagnetic field minima make reading difficult
Solution Approach 1:
The patent applies dynamics by making the receiver impedance adjustable rather than fixed. The receiver transitions between different impedance states (first and second configuration impedances) to dynamically adapt to interference conditions. This allows the system to maintain reliable detection even when multiple receivers are placed close together, resolving the contradiction between detecting multiple items and maintaining detection accuracy due to interference.
Solution Approach 2:
The patent changes the impedance parameter of the receiver to solve the interference problem. By alternating between first and second configuration impedances, the receiver modifies its electromagnetic characteristics to avoid falling into field minima and reduce interference effects. This parameter change enables reliable detection of multiple receivers simultaneously while maintaining high detection accuracy.
2Loss of time
If receivers send simultaneous responses, then detection can be performed quickly, but interference causes detection errors
Solution Approach 1:
The patent uses dynamics by implementing time-varying impedance configurations. receivers alternate between different impedance states during the detection process, which spreads out the response signals in time and frequency domain. This dynamic approach allows simultaneous detection attempts while reducing the harmful interference effects that cause detection errors when all receivers respond at the same time.
Solution Approach 2:
The patent employs periodic action through the alternating impedance configurations. Receivers cycle between first and second configuration impedances in a periodic manner, creating time-separated transmission patterns. This periodic variation in impedance allows the system to maintain quick detection while the temporal separation of signals reduces interference-induced errors.
3Reliability
If the system detects receivers one by one, then detection accuracy is maintained, but checkout time increases
Solution Approach 1:
The patent merges the detection of multiple receivers into a single simultaneous operation. By using adjustable impedance to enable multiple receivers to be detected at the same time without significant interference, the system combines what would traditionally be sequential detection operations into one parallel operation. This maintains high detection accuracy while dramatically increasing checkout speed.
Solution Approach 2:
The patent makes the detection system universal by enabling it to handle multiple receivers with the same detection mechanism. The adjustable impedance feature allows any receiver in the tray to be detected reliably regardless of its position or potential interference from other receivers. This multi-functionality allows the system to detect multiple items simultaneously without sacrificing accuracy, thereby increasing productivity.
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
The system efficiently detects and identifies multiple receivers, regardless of their position, improving the accuracy and speed of item identification in environments with interference.
Implementation Method 1
a global antenna (42) adapted to transmit a primary wave (OP) and to receive a secondary wave (OS) transmitted by the adjustable receiver (30) in response to the reception by this receiver of the primary wave (OP)
Implementation Method 2
the adjustable receiver (30) having a modifiable impedance (Z) thus influencing the transmitted secondary wave (OS), the adjustable receiver (30) being initially in a detection mode where the adjustable receiver has a basic impedance
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
A method for detecting receivers comprises a step of detecting a receiver, in which step a global controller detects an adjustable receiver when a global antenna receives a secondary wave transmitted by the adjustable receiver, followed by a reconfiguring step in which the global controller commands a controller of the detected adjustable receiver to pass to an interaction mode in which the impedance of the adjustable receiver is alternated between a first configuration impedance and a second configuration impedance in order to detect other receivers. The reconfiguring step is of a duration of an order of magnitude higher than the duration of each alternation of the first and second configuration impedances.