Signal-processing systems and methods for RFID-tag signals
First Claim
1. A method of reading an analog radio-frequency identification (RFID) signal communicated by a RFID tag, wherein the analog RFID signal comprises a sequence of bits, comprising:
- causing the RFID tag to communicate multiple copies of the analog RFID signal;
receiving the multiple copies of the analog RFID signal, wherein at least some of the received multiple copies differ from each other;
converting the multiple received analog RFID signals to corresponding multiple digitized RFID signal representations each comprising a plurality of digital samples; and
processing the multiple digitized RFID signal representations on a sample-by-sample basis to obtain a recovered digital RFID-tag signal representative of said sequence of bits.
4 Assignments
0 Petitions
Accused Products
Abstract
Systems and methods for reading a RFID-tag signal in the presence of noise and other propagation and circuit impairments using a RFID-tag reader are disclosed. The method includes receiving with a RFID-tag reader multiple copies of an original RFID-tag signal from a RFID tag. The original RFID-tag signal comprises an original bit sequence representative of information stored in the RFID tag. At least some of the received RFID-tag signal copies differ from one another due to noise or other signal impairments. The received multiple copies are processed on a sample-by-sample basis in the RFID-tag reader using digital signal processing techniques to obtain an improved received digitized RFID tag signal that substantially removes the noise and other impairments. This improved signal is used to recover the original bit sequence and thus the information stored in the RFID tag.
-
Citations
24 Claims
-
1. A method of reading an analog radio-frequency identification (RFID) signal communicated by a RFID tag, wherein the analog RFID signal comprises a sequence of bits, comprising:
-
causing the RFID tag to communicate multiple copies of the analog RFID signal; receiving the multiple copies of the analog RFID signal, wherein at least some of the received multiple copies differ from each other; converting the multiple received analog RFID signals to corresponding multiple digitized RFID signal representations each comprising a plurality of digital samples; and processing the multiple digitized RFID signal representations on a sample-by-sample basis to obtain a recovered digital RFID-tag signal representative of said sequence of bits. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A radio-frequency identification (RFID) reader apparatus for reading an analog RFID signal communicated by a RFID tag, wherein the analog RFID signal comprises a sequence of bits, comprising:
-
an antenna adapted to receive analog RFID signals communicated by the RFID tag and to emit RFID tag interrogation signals so as to cause the RFID tag to communicate multiple copies of the analog RFID signal; a demodulator operably coupled to the antenna and adapted to demodulate the received analog RFID signals; an analog-to-digital (A/D) converter operably coupled to the demodulator and adapted to convert each demodulated analog RFID signal to a corresponding digitized RFID signal representation comprising a plurality of digital samples; and a central processing unit operably coupled to the demodulator and adapted to process, on a sample-by-sample basis, multiple digitized RFID signal representations to obtain a digitized RFID signal representative of said sequence of bits. - View Dependent Claims (13, 14)
-
-
15. A method of reading a RFID-tag signal communicated by a RFID tag and having an original sequence of bits, the method comprising:
-
receiving multiple copies of the RFID-tag signal using a RFID-tag reader, wherein at least some of the received multiple copies differ from one another; digitizing the received multiple copies to form digitized RFID-tag signal representations each comprising digital samples; and processing the digitized RFID-tag signal representations on a sample-by-sample basis to obtain a recovered digitized RFID-tag signal that yields said original sequence of bits. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24)
-
Specification