RFID tag quantity estimation system, RFID tag quantity estimation method
AssigneeSoochow University
InventorsZhe Li, Wei Deng
Life of this patent
Estimating the term…
Abstract
This application discloses a tag quantity estimation system and method of RFID. A processor-readable medium was disclosed at the same time. This estimation method applies a spatial diversity gain existing in a multi-antenna system. Separated and sequentially stacked the real parts and the imaginary parts of the multiple signals received by multiple antennas. Then, a tag quantity estimation problem is converted into a data clustering problem in high-dimensional space. In this way, the overlapped cluster data in low-dimensional space can be separated in the high-dimensional space, thereby improving the accuracy of tag quantity estimation.
Claims7
A method for estimating the quantity of RFID tags using an estimation system comprises;
- a transmitting antenna for transmitting RFID reader signals with carrier component;
- multiple receiving antennas for receiving RF tag signals;
- a down-conversion module for down-converting the RF tag signals received by the receiving antennas to baseband signals;
- a carrier cancellation module for removing the carrier component from the received RF tag signals;
- and
- a tag quantity estimation module for estimating the quantity of tags;
- wherein the method comprises the following steps:
- S00:
- obtaining multiple information blocks of the RE tag signals as reference data for the RFID tag quantity estimation;
- S10:
- converting the received RF tag signals to baseband signals based on the down-conversion module;
- S20:
- removing the carrier components based on the carrier cancellation module to obtain a digitized baseband signal and denoting the baseband signal by complex number;
- S30:
- estimating the observed noise power in the complex baseband signal with the carrier component removed and normalize the estimate by noise normalization module;
- S40:
- processing the normalized complex baseband signals through tag signal preference module, the tag signal preference module being preset with a tag power threshold, selecting baseband signals that are greater than the preset power threshold;
- S50:
- processing the selected complex baseband signals into high-dimensional tensor generation module, wherein real part and imaginary part are taken for the complex baseband signals respectively, and the dimension of the tensor generated by the high-dimensional tensor generation module is two times the quantity of the input;
- S60:
- calculating the quantity of high-dimensional clusters formed by the high-dimensional tensor based on adaptive clustering discrimination module;
- S70:
- process the quantity of high-dimensional clusters obtained by the adaptive cluster resolution module into temporary tag count module and record the output of the temporary tag count module as the result of temporary tag count calculation;
- S80:
- if current tag power threshold reaches a maximum power of the tag, all temporary tags quantity calculation results recorded are passed through the tag quantity estimation module to obtain final tags quantity;
- S90:
- if the current tag power threshold does not reach the maximum power of the tag, the power threshold is adjusted upward and proceeds to step S40.
Dependencies are inferred from the claim text.