Printed RFID Antenna Array Subarray Interference Encoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Printed RFID tags have limitations such as low memory density and high reading costs, and they cannot rewrite data after being printed, which restricts their functionality compared to passive or active RFID tags.
Innovation Solution
A radio frequency identification (RFID) system that includes a printed RFID antenna array with multiple antenna elements on a substrate, an electronic reader device with a transmit and receive antenna, and demodulation and decoding circuitry to receive and decode compound signals from different subsets of antenna elements, allowing for increased data encoding and retrieval without the need for microchips.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple antenna elements are used to increase memory density, then the data encoding capacity is improved, but the reading complexity and cost increase
Solution Approach 1:
The antenna array is divided into multiple independently controllable antenna elements, where each element can be selectively excited or deactivated. This segmentation allows the system to divide complex reading operations into simpler sub-operations, reading from subsets of elements rather than requiring simultaneous processing of all elements, thereby reducing reading complexity while maintaining high memory density
Solution Approach 2:
The system excites only a subset of antenna elements (N elements) at a time rather than all elements simultaneously. This partial action approach reduces the complexity of signal processing and reading operations while still achieving high memory density through multiple reading passes from different subsets of elements
2Area of moving object
If antenna elements are placed closer together to increase density, then the surface area is reduced, but the signals from individual elements interfere with each other
Solution Approach 1:
The system deliberately exploits the interference patterns between closely spaced antenna elements by controlling the phase and amplitude of excitation signals. Constructive and destructive interference are used as encoding mechanisms, where the interference patterns themselves carry information. This converts the harmful interference into a useful feature for data encoding, allowing high-density packing while maintaining signal distinguishability
Solution Approach 2:
The system changes the excitation parameters (phase and amplitude) of individual antenna elements to control interference patterns. By adjusting these parameters, the system can create distinct signal signatures from different element subsets, enabling reliable reading despite close spacing and potential interference
3Power
If a larger number of antenna elements are excited simultaneously, then the signal strength is improved, but the ability to encode and retrieve distinct data increases
Solution Approach 1:
The full set of antenna elements is segmented into multiple subsets, with each subset containing N elements that can be excited simultaneously. This segmentation allows the system to maintain strong signals from each subset while using multiple subsets across different reading locations to encode and retrieve larger amounts of data, preventing information loss
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 solution enhances memory density and reduces reading costs by enabling efficient data encoding and retrieval from a smaller surface area, leveraging the interference patterns of multiple antenna elements to produce compound signals that can be demodulated and decoded for data extraction.
Implementation Method 1
an RFID transmit antenna sized to transmit excitation energy to a number N>1 of printed RFID antenna elements
Implementation Method 2
leveraging the interference patterns of multiple antenna elements to produce compound signals
Data Source
AI summary
A radio frequency identification (RFID) technique is disclosed. The technique includes a printed RFID antenna array including at least three printed RFID antenna elements and an RFID reader device with at least one RFID reader antenna sized to transmit excitation energy to a number N>1 of printed RFID antenna elements of the printed RFID antenna array, where N is less than a total number of printed RFID antenna elements of the printed RFID antenna array. The RFID reader antenna is configured to receive a plurality of compound signals from respective subarrays consisting of N of the printed RFID antenna elements of the printed RFID antenna array. The RFID reader device also includes a demodulator, a decoder, and an output interface.