International Core Journal of Engineering 2020-26 | Page 114
2019 International Conference on Artificial Intelligence and Advanced Manufacturing (AIAM)
RFID Multi-channel Design Method Based on
CDMA
Ping Du Yanfen Shen Yuewei Zeng
Building Information Department
Guangdong Construction Polytechnic
Guangzhou, China
[email protected] Building Information Department
Guangdong Construction Polytechnic
Guangzhou, China
[email protected] Building Information Department
Guangdong Construction Polytechnic
Guangzhou, China
[email protected]
tag by combining CDMA and time slot Aloha. Liu Xinqin et
al, from Taiwan University adopt Huffman sequence as the
spread spectrum [2]. It can be seen that domestic and
overseas scholars have conducted different researches and
explorations on code division RFID.
Abstract—This paper analyzes the application of Code
Division Multiple Access (CDMA) to ultra-high frequency
(UHF) RFID technology and the coding sequence of shift M-
sequence as CDMA. M-sequence is characterized by better
positive correlation and the sufficient number of orthogonal
codes, so the application of it in UHF RFID is the development
of RFID technology. This paper focuses on characteristics,
generation and multi-channel realization of M-sequence. The
integration of CDMA and RFID technology can realize the
simultaneous response of multiple tags and become a new anti-
collision method to improve the reading rate. This technology
brings new research direction of RFID to new area with
multiple channels, high spectral efficiency and high signal to
noise ratio.
Keywords—CDMA,
correlated operation
RFID,
M-sequence,
This paper breaks through the bottleneck of air interface
access capability of UHF RFID, adopts the concept of multi-
channel access, applies CDMA cellular communication
network to UHF RFID air interface, realizes the integration
of orthogonal code division access and spread spectrum
based on communication, establishes code division RFID
system and realizes the simultaneous access of multi-channel
tag information [3]. In this way, the reading rate can be
improved, the pressure of collision can be alleviated and the
spectral efficiency and anti-jamming capability can be
enhanced [4].
multi-channel,
I. I NTRODUCTION
II. CDMA S PREAD S PECTRUM M ETHOD BASED ON M-
At present, 5G era comes with higher speed and wide
development prospect. It is estimated that the connection to
5G in China will be more than 400 million in 2025. Internet
of things (IoT) relates any object to network by information
sensing equipment, so as to realize the intellectualized
identification, location, tracking and surveillance.
Constrained by the coverage of wireless network and
communication speed, IoT fails to truly develop. With the
advent of 5G network, supported by its great communication
speed, the development of IoT technology will embrace a
new breakthrough in future several years. With RFID
technology as the important and critical technology of IoT
technology [1], and the development of 5G technology,
people look forward to its performance and reading rate.
However, RFID technology requires further optimization and
innovation to promote the integration and development of 5G
technology and IoT.
SEQUENCE
The spread spectrum technology is to make use of spread
spectrum code sequence caused by spread spectrum code
generator to module digital signal, so as to widen the
spectrum of signal. The signal widened is modulated to radio
frequency to be sent out. The received broadband radio
frequency signal can realize related dispreading by locally-
caused spread spectrum code sequence that is same to
generating terminal, and recover to raw information output.
The spread spectrum technology can bring multiple benefits
to communication system [5].
Firstly, strong anti-jamming capability. The wider the
widening channel of spread spectrum is, the higher the
processing gain received is, the larger the jamming margin,
and the stronger the anti-jamming capability.
Secondly, better confidentiality. Digital information
modulated is similar to random noise. When the receiving
terminal performs dispreading, only simultaneous spread
spectrum code is adopted to correctly recover information
sent. In this way, information is confidential.
The air interface of UHF RFID currently adopts single-
channel access, and collision decision is one of cores of
communication protocol. The anti-collision algorithm has
been improved for several times, however, people fail to
achieve fundamental breakthrough, especially the collision
between multiple readers in dense configuration. American
Caro Mutti and Caristian Floerkeneire establish the tag
application scheme with the combination of CDMA and
Aloha through Gold sequence and Kasami code. Gustaw
Mazurek, in Active RFID System With Spread-Spectrum
Transmission, conducts a research on code division channel
by adopting 16 127-bit Gold sequence. In 2011, German
Andress Loefler et al. realize the simulation of semi-passive
978-1-7281-4691-1/19/$31.00 ©2019 IEEE
DOI 10.1109/AIAM48774.2019.00025
Thirdly, the anti-fading and anti-multipath interference
capability. The spread spectrum system owns potential anti-
frequency-selective-fading capability, and can effectively
overcome multipath interference.
Fourthly, CDMA easily realized. The pseudo-random
sequence spread spectrum is adopted in spread spectrum
communication system so as to realize the CDMA
communication.
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