DESIGN AND CHARACTERIZATION OF RFID MODULES IN MULTILAYER CONFIGURATIONS A Thesis Presented to The Academic Faculty by Sabri Serkan Basat In Partial Fulfillment of the Requirements for the Degree MASTERS OF SCIENCE IN ELECTRICAL AND COMPUTER ENGINEERING Georgia Institute of Technology December, 2006
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DESIGN AND CHARACTERIZATION OF RFID MODULES IN
MULTILAYER CONFIGURATIONS
A Thesis Presented to
The Academic Faculty
by
Sabri Serkan Basat
In Partial Fulfillment of the Requirements for the Degree
MASTERS OF SCIENCE IN ELECTRICAL AND COMPUTER ENGINEERING
Georgia Institute of Technology December, 2006
DESIGN AND CHARACTERIZATION OF RFID MODULES IN
MULTILAYER CONFIGURATIONS
Approved by: Dr. John Papapolymerou School of Electrical and Computer Engineering Georgia Institute of Technology
Dr. Joy Laskar School of Electrical and Computer Engineering Georgia Institute of Technology
Dr. Manos M. Tentzeris, Advisor School of Electrical and Computer Engineering Georgia Institute of Technology
Date Approved: November 20, 2006
To My parents Nurdan, H. Ihsan, and my sister Z.Destan Basat for their love, encouragement, and support
iv
ACKNOWLEDGEMENTS
The author would like to thank Prof. Manos M. Tentzeris for his guidance and
encouragement and more importantly being a friend. The author owes great debt to the
ATHENA research and especially to Dr. Symeon Nikolaou for his assistance in the
preparation of this document, Amin Rida, Li Yang, and Toni Ferrer-Vidal of the PIREAS
RFID team for providing assistance in the research activity. The author would also like to
thank Dr. Massimiliano Pezzoli, Dr. Valerio Parisi, Dr. Melih Doksanbir, Dr. Alp Engin
Can, Dr. Melissa Lee Casey, and Dr. Emre Kepenek for providing the inspiration and
support in completion of this work. Most importantly the author is eternally grateful for
the motivation to try for the best that was instilled into the author’s mind by his family
Nurdan Basat, H. Ihsan Basat, and Z. Destan Basat.
v
TABLE OF CONTENTS
Page
ACKNOWLEDGEMENTS…………………………………………………………….iv
LIST OF TABLES……………………………………………………………………..viii
LIST OF FIGURES……………………………………………………………………..ix
LIST OF SYMBOLS AND ABBREVIATIONS……………………………………...xii
SUMMARY…………………………………………………………………………….xiv
CHAPTER 1: INTRODUCTION………………………………………………………1
1.1 RFID Basics.…………………………………………………………..1
1.2 History of RFID……………………………………………………….6
1.3 Background: How Does the RFID System Work?................................9
1.3.1 Reader…………………………………………………………...9
1.3.1.1 The HF Interface……………………………………….11
1.3.1.2 The Control Group..………………….………………...11
1.3.2 Tag……………………………………………………………..14
1.3.2.1 Antenna………………………………………………..14
1.3.2.2 Integrated Circuit (IC)…………………………………22
1.3.3 Coupling Mechanisms…………………………………………24
1.3.3.1 Inductive Coupling…………………………………….26
1.3.3.2 Modulated Backscatter………………………………..27
1.3.3.3 Beacon (Transmitter) Type...………………………….28
1.3.3.4 Transponder Type……………………………………..29
1.4 Summary……………………………………………………………..30
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CHAPTER 2: CHALLENGES AND PROBLEMS IN RFID TAG DESIGN AND RESEARCH MOTIVATION………………………………………..31
2.1 The Cost of RFID Tag………………………………………………32
2.2 Size Limitations and Optimization…………………………….........32
APPENDIX A: LIST OF PUBLICATIONS……………………………………….…94
APPENDIX B: PORT OF SAVANNAH FIELD TEST SET-UP AND TABULATED DATA ....………...…………………………………... 95
REFERENCES………………………………………………………………………...115
viii
LIST OF TABLES
Page
Table 1: Single and Double-layer lumped component model R, L, C values………… 49
Table 2: Simulated antenna parameters and measured read range…………………….. 64
Table 3: S-shape RFID antenna performance parameters and measured read range …. 71
Table 4: Lumped element model values for the s-shape and the bandwidth optimized
s-shape designs…………………………………………………………………77
Table 5: Active UHF RFID test set-up for container tracking and tag
positions ………………………………………………………………………. 96
Table 6: Active UHF RFID Conducted field test with the times………………………..98
Table 7: Overall active UHF RFID tags by location on the containers in the stack.….. 114
ix
LIST OF FIGURES
Page
Figure 1: Basic RFID components.……………………………………………………… 1
Figure 2: RFID Technology examples in industry (Courtesy of Phillips)………………. 2
Figure 3: Active vs. Passive Tag.………………………………………………………...3
Figure 4: Effect of Environmental conditions and RFID system performance at different RFID frequency bands (courtesy of Phillips).………………………………... 5
Figure 5: The milestones in RFID technology [1]…………………………………….…7
Figure 6: General RFID reader diagram ………………………………………………..10
Figure 7: Sub-block RFID reader diagram ……………………………………………. 10
Figure 8: Geometrical representation of the sinusoidal current filament source ……… 15
Figure 9: Field regions of an antenna.…………………………………………………..16
Figure 10: Elevation plane amplitude patterns for a thin dipole with sinusoidal current distribution ( l = λ /4, λ /2, 3λ /4,λ ) [8]. …………………………………. 18
Figure 11: Three and Two-dimensional amplitude patterns for a thin dipole of and l = 1.25λ sinusoidal current distribution [8].…………………………………... 19
Figure 12: Current distributions along the length of a linear wire antenna[8]…………. 20
Figure 13: Basic RFID IC Block Diagram [5]…………………………………………. 23
Figure 14: Near-field (LF and HF) and far-field (UHF) coupling mechanisms.………. 25
Figure 15: Calculation of magnetic field B at location P due to current I on the loop….38
Figure 18: Single-layer (Left) and double-layer (Right) 13.56 MHz HF RFID tags.….. 41
Figure 19: Rectangular thin film inductor ……………………………………………...43
Figure 20: Two conductor segments for mutual inductance calculation.……………….44
Figure 21: The simple series resonance circuit model…………………………………..46
x
Figure 22: Lumped element model for single-layer and double-layer 13.56 MHz HF RFID tags.…………………………………………………………………...48
Figure 23: The single-layer and double-layer input impedance (50 Ohm normalization) and return loss (28 kOhm normalization) results for 13.56 MHz HF RFID
tag……………………………………………………………………………52
Figure 24: Current flow in UHF RFID Tag antenna …………………………………....57
Figure 25: The three different RFID antenna designs for tire application ….…………..58
Figure 26: Cross-sectional view of RFID Tag placement in tire material ……………...59
Figure 27: E-phi=0 (x-z) and E-phi=90 (y-z) planes radiation patterns (Directivity vs. elevation angle theta) for the three 915 MHz UHF antenna designs in tire material. Antennas are located in the horizontal plane.……………………..62
Figure 28: S11 input load impedance Smith chart (50-Ohm reference) plots for the three 915 MHz UHF antenna designs in tire material (range of frequency= 500-1500 MHz).………………………………………………………………… 64
Figure 29: 915 MHz UHF RFID s-shape antenna structure and double inductive stub matching network……………………………………………………....68
Figure 30: Fabricated 915 MHz UHF RFID s-shape antenna and antenna direction of current flow …………………………………………..………………………70
Figure 31: Input impedance of the simulated 915 MHz UHF RFID s-shape antenna…..72
Figure 32: Three- and two-dimensional far-field radiation plots for 915 MHz UHF s-shape antenna.……………………………………………………….……….73
Figure 33: Simulated input impedance of the 915 MHz UHF s-shape antenna………….74
Figure 34: 915 MHz UHF RFID s-shape antenna structure with optimized bandwidth showing the matching stubs.………………………………………………...75
Figure 35: Measured and simulated data of return loss for the 915 MHz UHF s-shape antenna.………………………………………………………………………76
Figure 36: Equivalent circuit for 915 MHz UHF s-shape antenna structure shown in Figure 28.……………………………………………………………………77
Figure 37: The Port of Savannah.………………….……………………………………81
Figure 38: Graphical view of tag placement on containers, container placement in stack, and reader position (Courtesy of CarrierWeb).……………………....82
xi
Figure 39: Containers in the stack positioned during the day of the measurement for the active 915 MHz UHF RFID field test .………………………………... 100
Figure 40: Canyon effect (Waveguiding) case active 915 MHz UHF RFID test set-up for container tracking.……………………………………………………... 102
Figure 41: The Canyon effect for detection of active 915 MHz UHF RFID tags in the middle container stack.………………………………………………………85
Figure 42: Radiation patterns in x-z planes with (RIGHT) and without (LEFT) metal surface.………………………………………………………………………86
The fabricated single-layer and double-layer tags are displayed in Figure 18. The
center of the single and double-layers are Ports 1 and 2 where the IC is assembled. These
two tags were fabricated using the same framing process.
41
Figure 18. Single-layer (Left) and double-layer (Right) 13.56 MHz HF RFID tags.
3.1.2 RLC Calculation
In order to design spiral coil antennas, the inductance (L), the resistance (R), and
the capacitance (C) of the antennas are needed to be characterized. From these values, the
quality factor, Q, of the inductor which would give the efficiency of the tag can be also
computed. The L and R are calculated as a starting point in the design process. The C is
quite difficult to numerically calculate because of the distributed capacitance of the tag
[29]. The circuit model that is also proposed in this paper is used to find the various
different capacitances.
R is comprised of DC and AC resistances of the conductor etched on dielectric
[28]. The DC resistance is due to the even distribution of charge carriers through the
entire cross-section of the metal trace and is given by:
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(9)
It clearly shows that a smaller cross-sectional area (9) causes higher DC resistance in the
metal trace. The resistance must be kept as small as possible to achieve higher Q inductor
coil antenna. For this reason, a larger diameter coil must be chosen for the RFID antenna.
As the frequency increases, the magnetic field is concentrated around the center
of the conductor metal trace and which in return increases the reactance near the center
that results in increased impedance [29]. This increased impedance forces the current to
flow more closely to the edges of the conductor. This phenomenon is widely known as
the skin effect. The depth into the conductor at which the current density falls to 1/e or
37% of its value along the surface is known as the skin depth.
(10)
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The net result of the skin effect is an effective decrease in the cross-sectional area
of the conductor; therefore, a net increase in the AC resistance of the conductor occurs.
For the conductor etched on dielectric substrate the AC resistance is,
(11)
where w is the width and t is the thickness of the conductor.
Figure 19. Rectangular thin film inductor.
The inductance of a thin film inductor with a rectangular cross-section as
displayed in Figure 19 is [29],
(12)
where w is the width in cm, t is the thickness in cm, and l is the length of the conductor in
cm. When an inductor made of straight segments is considered as shown in Figure 20, the
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L is the sum of self-inductances and mutual inductances [30] as shown below.
Figure 20. Two conductor segments for mutual inductance calculation.
(13)
Lo is calculated by adding the inductances of individual segments as shown in (12). The
mutual inductance results from the magnetic fields produced by adjacent conductors. The
mutual inductance is positive when the directions of currents on the conductors are in the
same direction and negative when they are in opposite directions.
The mutual inductance between two parallel conductors as presented in (14) is a
function of the length of the conductors and of the geometric mean distance between
them. It is calculated by,
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(14)
where l is the length of the conductor in cm and F is the mutual inductance parameter and
computed as,
(15)
where d is the geometric mean distance between the two conductors, which is
approximately equal to the distance between the track centers of the conductors.
In Figure 20 the two conductor segments are shown as mentioned before. The j
and k in the figure are the indices for the conductor segments, and p and q are the indices
of the length for the difference in the length of the two conductors. This configuration in
Figure 20 occurs between conductors in multiple turn spiral inductor. The mutual
inductance of the conductors’ j and k is calculated using,
(16)
and if the length l1 and l2 are the same (l1= l2), then (16 d) is used. Each mutual
inductance term as shown in (14) is computed by
46
(17)
and LT is calculated based on the mutual inductances and the self inductances. It should
be again noted that for RFID coils the calculated true inductance may differ from the
resulting inductance in the final design due to the distributed capacitance and additional
conductor lengths in the fabrication process. Because of this fact, inductance calculations
are mainly used as a starting point in the final design.
3.1.3 RLC Circuit Modeling
A 13.56 MHz rectangular coil antenna can be simply modeled as a series
resonance circuit as shown in Figure 21 to understand the effect of bandwidth and quality
factor ,Q, on
Figure 21. The simple series resonance circuit model.
47
antenna performance [29]. The half power (3 dB) frequency bandwidth is calculated
using the resistance r and inductance L, and given by,
(18)
where Q is found using (18) and the resonant frequency, fo , as shown below in (19). The
series
(19)
circuit forms a voltage divider where the voltage across the inductor coil, Vo, is given by,
(20)
where XL and XC are the inductor and capacitor reactances and Vin is the input voltage.
When the circuit is resonant at the specified frequency, XL = XC and (20) becomes as
shown below.
(21)
48
(21) indicates that the output voltage is a function of the Q and the input voltage. Since
the input voltage is limited by the reader, read range can be increased by increasing the Q
[29].
The series circuit model gives a synopsis of the general behavior of inductor coil
antennas; however, this model does not give any information about the distributed
capacitance due to the substrate effects and connecting pads. A lot of research has been
conducted in RF inductor modeling [31, 32].With the helpful insight of this work, a more
complicated lumped element model is presented in Figure 22. This model includes the
Figure 22. Lumped element model for single-layer and double-layer 13.56 MHz HF RFID tags.
substrate capacitances and losses as well as the resistance, capacitance, and inductance
changes with the addition of the pads and additional metal trace lengths/widths during the
fabrication process.
Figure 22 presents the lumped element model for both the single-layer and the
double-layer tags. The model is the same for the two cases with different R, L, and C
values because the double-layer tag is merely two single-layer tags in series resulting
Ls: the series inductance of the square spiral Rs: the ohmic losses in the metal traces of the spiral Cp: capacitive coupling due to the electrical field between the spiral tracks and the pad capacitance Rp: resistance in series with Cp Cadh: the adhesive material capacitance between the coil and the PET substrate Csub: the PET substrate capacitance Rsub: the resistive loss in the PET substrate Ric: IC resistance Cic: IC capacitance
49
from the way the two inductor coils are connected to each other. Since one-port
measurement was conducted, the second port was shorted as seen in the model. This
model was run through ADS simulation software’s optimization tool to obtain the freq-
independent R, L, and C values using the input impedance results of the one-port
measurement.
3.1.4 Experimental Results and Discussion
The R, L, and C values from the single-layer and double-layer lumped element
models are presented in Table 1. The one-port measurement of the reflection coefficient
(S11) gives the input impedance of the tag for both cases as shown in Figure 17. The
lumped element model was optimized so that the measured input impedance data and the
model data align perfectly. The IC was placed and the return loss was also measured as
shown in Figure 17 again for both cases. The IC’s parallel load capacitance and
resistance (23.5 pF and 28 kOhm) with the input impedance of the tag create the resonant
circuit centered at 13.67 MHz (single-layer) and 13.94 MHz (double-layer).
Table 1. Single and Double-layer lumped component model R, L, C values.
The double-sided metal tracing creates more parasitic capacitance as seen from
the Cp, Csub, and Cadh in Table 1. The substrate resistance, Rsub, is also quite high for
both cases indicating how lossy the material is. The series inductance, Ls, and resistance,
50
Rs, characterize the inductor coil. The Ls depends on the overall length of the metal
inductor coil; meanwhile, the Rs is mainly controlled by the width of inductor coil. The
Rp is the result of pad capacitance which dominates in the single-layer case due to the use
of bridge structure to connect one end of the inductor to the other.
The performance of the coil antenna as the radiating element depends on the
efficiency which defines the read range of the tag. The efficiency is mainly characterized
for inductor coil type antennas by the Q as mentioned before. The calculated Q values for
the single-layer and the double-layer are 54.7 and 15.2 respectively. The fabricated tags
yield operational distances of 37 cm (single-layer) and 22 cm (double-layer). The
inductance of the coil plays a major role in the near-field coupling. The magnetic flux
created inside the coil due to the inductive coupling between the reader and the tag is a
function of the size and the number of turns of the coil. Another factor that limits the
efficiency of the coil antenna is the PET dielectric loss (tanδ=0.017). As seen from Table
1, the double-layer Rsub is more resistive than the single-layer which indicates the
presence of power leakage into the substrate. This also contributes to lower the efficiency
as well as the read range. The plots in Figure 23 display the relationship between read
range and return loss. The amount of power that is radiated by the double-layer tag is
about 5 dB less than the single-layer. This explains why the read range of the double-
layer tag drops to almost half of the single-layer.
In contrast to UHF (i.e. 915 MHz applications) systems, the RF field at 13.56
MHz is not absorbed by water or human tissue, which allows operation through water or
human beings with the trade-off of having a larger physical size. The influence of the air
51
Single-layer Input Impedance
0.964
0.966
0.968
0.97
0.972
0.974
0.976
0.978
12 12.5 13 13.5 14 14.5 15
freq, MHz
Rea
l (S1
1)
0.16
0.18
0.2
0.22
0.24
Imag
(S11
)
Real part (measured)Real part (simulated)
Imag part (measured)Imag part (simulated)
Imagfreq=13.56 MHzImag(S11)=0.158
Realfreq=13.56 MHzReal(S11)=0.986
Imag
Real
Double-layer Input Impedance
0.94000
0.94500
0.95000
0.95500
0.96000
0.96500
0.97000
0.97500
12 12.5 13 13.5 14 14.5 15
freq, MHz
Rea
l (S1
1)
0.15000
0.17000
0.19000
0.21000
0.23000
0.25000
0.27000
0.29000
Imag
(S11
)
Real part (measured)Real part (simulated)Imag part (measured)Imag part (simulated)
Figure 23. The single-layer and double-layer input impedance (50 Ohm normalization) and return loss (28 kOhm normalization) results for 13.56 MHz HF RFID tag.
moisture on the performance and efficiency is also negligible [27].As a result of the near-
field operation of 13.56 MHz RFIDs (power decreases with 6th order of distance), the
disturbing influence of adjacent systems or external noise is much lower compared to
UHF systems (power level decreases as the square of the distance) [27], something
important in RFIDs for tire/pallet inventories.
53
3.2 Summary
Designing an inductor-coil embedded antenna for 13.56 MHz RFIDs present
various challenges such as the parasitic capacitance and dielectric material (i.e. PET)
limitations. The parasitic capacitance shifts the resonant frequency, so capacitance
compensation should be considered such as adding series pad capacitance to reduce the
effect. The dielectric materials used for these applications are generally very cheap yet
lossy. This weakens the read range performance of the tag. Better performing 13.56 MHz
RFID tags could be achieved by using less lossy dielectric materials and diminishing the
ill-effect of parasitic capacitance by introducing series pad capacitance. The efficiency of
the voltage transfer, which results from the inductive coupling between the reader and the
tag coils, can be increased significantly with high Q (highly inductive yet low resistive)
circuits. The read range of 13.56 MHz is relatively longer than that of 125 kHz device
because of the fact that the antenna efficiency increases as the frequency increases. In
addition to this, the growth of the 13.56 MHz RFID market has benefited from the better
performance of 13.56 MHz RFIDs compared to UHF RFIDs in complicated
environments that get affected by factors such as air humidity or presence of human
beings and water.
54
CHAPTER 4
915 MHz UHF RFID TAG DESIGN FOR AUTOMOTIVE TIRE
APPLICATION
The recent advances in cost-effective low-power electronics and packaging have
enabled the RFID tag as a likely substitute for barcodes [33, 34].The RFID tags also
present challenges in behavioral modeling and simulation of the antenna and
module/package integration in parameters such as the pad capacitance, the estimation of
the parasitics due to the proximity of IC and antenna, and the identification of a low-cost
low-loss light material.
In this chapter, three novel miniaturized antennas are presented for 915 MHz
passive tags that are designed to be embedded inside commercial automobile tires. The
necessary power required to energize and activate the tag’s microchip is drawn from the
electromagnetic field provided by the reader unit’s antenna. The transponder IC stores the
tire's unique ID, which can be associated with the vehicle identification number. The chip
also stores information about when and where the tire was made, its maximum inflation
pressure, size and so on. The tag utilizes the low cost lead frame based IC packaging
process and the miniaturized antenna is built in the lead frame.
Passive ICs are intrinsically highly reactive because of the necessary power to
bias the IC which is delivered by charging up the IC through electromagnetic coupling.
Due to the low resistive yet high capacitive impedance of the microchip, novel design
55
approach for the RFID antennas have to be proposed comprising of antennas that are
lowly resistive (high efficiency) and highly inductive for matching to the input
impedance of the transponder IC.
One remarkable improvement to bar code systems by RFID is the possibility to
read and write on the information-carrying element on the item. The transponder can
carry several kilobytes of data that can be 1) read selectively, 2) appended with new data
elements, and 3) modified, i.e. erased and overwritten. These features depend on the type
of tag used. The tag may have its own processor capable of performing complicated tasks
with the data stored in its memory. [27] Another important feature is the capability of the
RFID reader to interact with the tag with no line-of-sight since the tag is placed inside the
tire. If a tag is in the area reached by the reader, it can be detected and communicated
with. Thus, the identification of items can be achieved without having to unpack them.
This adds to the durability of the tag as well as to the convenience of easily reading each
item, as it does not have to be outside the package protecting the item.
An RFID tag of UHF band employs far-field radiation of the real power contained
in free-space propagating electromagnetic plane waves due to its shorter wavelength,
while a 13.56 MHz HF tags is utilizing inductive coupling in the near-field region as the
wavelength is much longer. The main difference is that in UHF systems the resistive part
of the radiating power is used to communicate with the passive tag where in HF systems
the reactive part of the radiating power is used. The IE3D design tool, which is based on
method of moments (MoM), is used to optimize and analyze the tag. This tool is used as
main platform to design and come up with certain antenna performance parameters such
as gain, radiation pattern, and efficiency. Three different 7cm x 3cm (equal in area or
56
smaller) antenna designs are built to make sure maximum range is obtained. Achieving
that range has been a challenge because the lossy tire rubber makes it harder to get an
impedance matching and creates additional power loss in the tire rubber. The tested tags
in actual tires yield maximum operational distance ranging from 48.7 cm to 52.5 cm
which is well within the required range (50 cm) for the application.
4.1 Design Approach
The IC input impedance for the tire application is 17-j350 Ω, which means the
load antenna impedance should be 17+j350 Ω for maximum power transfer (conjugate
matching). This requires the antenna impedance to be low- resistive yet high-inductive.
Various antenna designs like dipole, printed patch, log-spiral, and meander-line have
been proposed as a solution in the past.[13,14,15,35] Nevertheless, a novel approach has
to be followed to keep the antenna size small and the load impedance to have a low real
part (small resistance) and a high positive imaginary part (high inductance). To achieve
this, an inductive element needs to be incorporated into the antenna. In addition to this,
the metal size is desired to be as big as possible to obtain better radiation parameters such
as directivity and efficiency through the larger radiating aperture, though it could increase
the metal loss leading to a trade-off in the antenna efficiency. Increasing the metal size
also lowers the surface resistance and increases current flow as shown in Figure 24. It is
for these above-mentioned reasons, a dipole antenna with inductive stubs and a metal
patch is used as the basis for the three antenna designs of this paper. The stubs provide
the inductive load impedance meanwhile the metal patch lowers the load resistance.
57
To accomplish maximum directivity and optimum radiation, the designs are built
to achieve half-wavelength (λr/2 ~9 cm in rubber material @ 915 MHz) resonance at first.
Figure 24. Current flow in UHF RFID Tag antenna.
In essence, the designs possess similarity to the half-wave dipole antenna; however, there
exists a trade-off between antenna-IC matching and resonance. Whenever the size is
increased to match for resonance, antenna-IC matching deteriorates. The miniaturization
of the antenna size is another issue, which requires the length of the antenna to be smaller
than the resonance length.
4.2 Antenna Design
The three RFID Tag antenna designs are shown in Figure 25. These antennas are
made of copper metal with a thickness of 200 um. The antenna is embedded inside tire
material that is basically rubber. (εr =3.0, tanδ=0.02) In addition to this, one-port
differential excitation, which is used to measure the actual antenna-IC configuration, is
employed to numerically calculate the return loss and antenna load impedance as well as
the read range measurement.
58
The single inductor stub as shown in Figure 25b is utilized to obtain the required
inductance where the triangular patch is the main radiator for Antenna#2. The other two
(a) Antenna#1 where minimum line spacing is 1.5 mm with W=14.5 mm, L=56 mm, 2 mm port separation, and trace width of 0.5 mm.
(b) Antenna#2 where minimum line spacing is 0.5 mm with W=30 mm, L=60 mm, 2 mm port separation and trace width of 0.5 mm.
(c) Antenna#3 where minimum line spacing is 0.5 mm with W=12 mm, L=67 mm, 2 mm port separation and trace width of 0.5 mm.
Figure 25. The three different RFID antenna designs for tire application.
59
designs utilize double stub configurations. Antenna#1 and Antenna#3 as shown in Figure
25a,c are also highly inductive due to the double stubs that are easily incorporated into
the radiator rectangular patches. This feature is proven to be very important to enhance
radiation because the inductive stub, which is used for antenna-IC reactance matching,
becomes more part of the radiating element by creating additional coupling with the
radiating element.
4.3 Embedding Process
The tire cross-section is displayed in Figure 26 showing the dimensions of the
tire, the rubber
Figure 26. Cross-sectional view of RFID Tag placement in tire material.
60
material, and the steel thicknesses. The position of the RFID Tag is also presented. The
tag is placed parallel to the outer steel mesh at a distance that depends on the tire size and
ranges between 4 to 8 cm above the inner steel mesh.
4.4 Antenna Results and Discussion
The radiation patterns for the three designs in tire rubber are shown in Figure 27.
All of the designs have doughnut-shaped radiation patterns in the phi=0 deg (x-z plane)
and phi=90 deg (y-z plane) planes as expected since the antennas are dipole type. The
creation of nulls in the horizontal plane (x-y plane) with dipole type of antennas is a
limiting factor. It is actually desired to achieve maximum radiation when the tag is read
in the plane (x-z or y-z planes) that is perpendicular to the RFID antenna. The horizontal
radiation is also crucial in terms of the orientation of the reader. The Interrogator (reader)
does not necessarily have to be positioned on top or bottom with respect to the RFID tag,
but the tire RFID tag should also have the functionality to be read from the sides as well.
In addition to this, the radiation pattern is suppressed and more in the horizontal plane (x-
y plane) when the tag is embedded in actual tire with the steel meshes. The steel meshes
that protect the tire from deformation act like two metal plates creating the waveguide
effect. For this reason, a second antenna tag can be placed as close as possible to the side
surface of the tire perpendicular to the parallel configuration displayed in Figure 27. The
dual polarization (horizontal and vertical) capture will improve the detection in the
direction vertical to the antenna (z-axis) where antenna is least likely to be read. Utilizing
two orthogonal tags (x-y horizontal plane and y-z/x-z vertical plane) would overcome this
obstacle in
61
(a) antenna#1
(b) antenna#2
62
(c) antenna#3
Figure 27. E-phi=0 (x-z) and E-phi=90 (y-z) planes radiation patterns (Directivity vs. elevation angle theta) for the three 915 MHz UHF antenna designs in tire material. Antennas are located in the horizontal plane.
case the application requires effective radiation characteristics in the horizontal plane.
63
(a) antenna#1
(b) antenna#2
64
(c) antenna#3
Figure 28. S11 input load impedance Smith chart (50-Ohm reference) plots for the three 915 MHz UHF antenna designs in tire material (range of frequency= 500-1500 MHz).
The antenna load impedances for the three antennas are shown in Figure 28,
verifying that they are high-inductive and low-resistive. The load impedance values are
displayed in Table 2 along with other radiation parameters namely
Table 2. Simulated antenna parameters and measured read range.
65
return loss, directivity, radiation efficiency, and read range in tire material and in actual
tire. As it can be seen from Table 2, the antenna efficiency determines how much
operational distance is needed for the tag. For example, although Antenna#2 and
Antenna#3 exhibit almost the same return loss and directivity, the read range is higher for
Antenna#3 due to higher radiation efficiency of this antenna. Still, the read range does
not only depend on the efficiency of the radiating antenna.
The first set of read ranges as presented in Table 2 are measured only with RFID
tag in tire material. When the tag is embedded in actual commercial tires, Antenna#1,#2,
and #3 yield operational distances of 52.8, 48.7, 52.0 cm respectively. The application
requires a read range of 50 cm due to anti-collision limitations, so the three designs are
acceptable including antenna#2 which requires further minor optimization. The reason
for the read range reduction is the presence of the steel meshes on the inner and outer
surfaces of the tire.
Further efficiency improvement can be accomplished in three ways: 1) Create
more coupling by surrounding the radiating patch with the inductive stub. The stubs that
enclose or join with the patch generate more current flow which enables the antenna to
radiate more. 2) Make the inductive stub more integrated with the radiating patch by
joining the stub and the patch. 3) Use a less lossy dielectric material which would
minimize excitation of substrate modes and power leakage into the dielectric.
66
4.5 Summary
Three novel antennas have been shown for 915 MHz UHF RFID applications for
tires. These antennas with low resistance and high inductance for the input impedance
provide a good example of a design procedure if the load impedance from the
transponder is unusually high in capacitance and low in resistance. The tag size plays a
major role in determining the read range: The smaller the tag, the smaller the energy
capture area, therefore the shorter the read range, especially complicated lossy media
such as tires. A proper design of the system and a thorough optimization of the
interrogator power, the antenna positioning and orientation, and an optimum tag in-tire
positioning helps to alleviate this limitation. Multiple tagging can be used to improve the
detection of the tags in both the horizontal and vertical planes. It has been observed that
the effective read range also depends on the absorption/attenuation factor of the type of
the material in which the tag is embedded.
67
CHAPTER 5
HIGH-EFFICIENCY 915 MHz UHF RFID TAG DESIGN ON LIQUID
CRYSTAL POLYMER (LCP) SUBSTRATE WITH HIGH READ-
RANGE CAPABILITY
The demand for flexible antennas with higher efficiency and more compact size
has increased in the recent years mainly due to the requirements for a higher and higher
read range performance of the increasingly used RFID tags and their almost ubiquitous
presence in the industry in security-related applications.
The passive UHF RFID tags see the widest use in supply-chain and retail
applications. One of the biggest advantages of passive UHF tags over the higher
frequency tags (i.e. 2.45 GHz RFID tags) is that they have a range, in many environments,
of over ten feet (and sometimes as much as tens of feet). Additionally, RFID readers can
scan hundreds of UHF tags simultaneously, whereas the lower frequency tags (VLF, LF,
and HF bands), already suffering from limited read range (~1-2 feet), can handle about
10% of that scanning capacity with a lower data transfer rate.
The proposed 915 MHz RFID tag employs far-field coupling of the real power
contained in free-space propagating electromagnetic plane waves due to its shorter
wavelength than, for example, the 13.56 MHz HF tags, where the inductive coupling of
the transponder tag operates in the near-field as the wavelength is much longer. The IE3D
and HFSS design tools are used to perform a system-level optimization of the tag, as well
68
as to design and come up with certain antenna performance parameters such as directivity,
radiation pattern, and efficiency.
In this chapter, the design and development of a unique high read-range high-
efficiency (95%) RFID antenna for the 915 MHZ UHF band is discussed. The RFID
exceptional characteristics are investigated in terms of antenna-IC matching and radiation
efficiency. This 915 MHz passive tag is a 3” x 3” omni-directional tag and yielded a read
range of 31 feet compared to a 4” x 4” leading commercial design of 26 feet tested range
in lab. This tag also possesses higher read power range (-7dBm to 30 dBm) than the
leading commercial design (-5dBm to 30 dBm). The proposed RFID antenna was
fabricated on 50.8 micron thick Liquid Crystal Polymer (LCP) and the read range of the
proposed RFID tags was experimentally verified.
5.1 Antenna Structure and Design Approach
The RFID antenna structure is shown in Figure 29. The single dipole antenna is
Figure 29. 915 MHz UHF RFID s-shape antenna structure and double inductive stub
matching network.
69
comprised of a resistive shorting stub with length j and width i, a double inductive stub,
and a radiating body. The 250-bit read/write chip is mounted on the 4 ports, namely RF1,
RF2, Vdd, and Vss at the feeding point as presented in Figure 29. RF1 and RF2 ports are
the RF signal terminals. Vdd is the open port to measure the IC bias voltage and Vss is the
ground port. The chip is designed to be operational with both single and dual dipole
antennas. The RF signal ports RF1 and RF2 are needed to be shorted to deliver the
information to the charge pump in the IC with the same phase. Time delay of the same
signal at the two RF ports leads to loss of information. For the single dipole antenna, RF2
port is grounded so that signal-ground (S-G) type of excitation can be created at the
feeding point.
It is crucial to achieve high radiation efficiency for high read range since most
commercial RFID antennas suffer from low efficiencies (~50-60%) [36]. In order to
accomplish maximum directivity and optimum radiation, the design is built to achieve
half-wavelength (λr /2 ~16 cm in air @ 915 MHz) resonance at first. This was taken about
to be the maximum length when the dipole antenna is stretched from one end to the other.
The tapered design is proposed to obtain a smoother transition from the connecting RF1
and RF2 pads of the IC at the interface to the single dipole antenna to reduce reflections
as much as possible. Another benefit from this tapering is used to maintain the high-
efficiency when the antenna is embedded in a dielectric material such as LCP, although
LCP’s dielectric constant (~3) is close to the free space.
The overall matching network is designed to conjugately match a chip impedance
of 73-j113 for maximum power delivery. The resistive shorting stub and the double
inductive stub make up the overall matching network to match to the chip input
70
impedance. The shorting stub mainly controls the resistive matching and the double
inductive stub controls the reactive matching. The double inductive stub structure is
composed of two inductive stubs to provide symmetry on both sides of the RFID tag [37].
In Figure 30 the fabricated 18 um thick copper antenna on flexible, low-cost, and
Figure 30. Fabricated 915 MHz UHF RFID s-shape antenna and antenna direction of current flow.
easily manufacturable LCP (εr =3.16, tanδ=0.00192) with 50.8 um thickness is shown.
The antenna can be used for sensor applications. For this reason, the antenna is also
designed to accommodate space for other surface components such as a sensor module
and a battery with minimum interference to the overall antenna performance.
5.2 Experimental Results and Discussion
The RFID antenna performance parameters are displayed in Table 3 below. The
calculated return loss [38] values at 915 MHz based on the 73-j113 Ω chip impedance for
the simulated and measured antennas are -15.97 dB and -13.78 dB respectively. One
major factor for the high efficiency is because of the way the current flow is directed as
71
presented in Figure 30. Since the direction of current flow in the top and bottom parts of
Table 3. S-shape RFID antenna performance parameters and measured read range.
the antenna always add up constructively for far-field radiation, the radiation efficiency is
maximized. The 5% loss in efficiency is mainly due to the amount of radiation loss in the
matching network. The RFID tag was also tested for read/write power levels. The read
power range was from -7 dBm to 30 dBm and the pattern generator was able to write
250-bit user data to the memory of the chip for power levels above 2 dBm. The length j
of the antenna’s shorting stub was reduced to half of the original length to observe the
performance difference. The simulated input impedance of the antenna becomes
44+j100.1 Ω. The resistance drops dramatically (higher return loss); meanwhile, the
inductance stays almost the same as expected. When this tag was tested, power levels
were from -5 to 29 dBm for reading and 3 dBm for writing. The read range was measured
to be close to 30 feet (9.14 m) in a room.This shows the effect of power transmission loss
between the antenna and the matching network. More power is needed to write on the
chip because of this loss in the matching network. Although the efficiency stays the same
(95%) compared to the original antenna in Table 3, read range is decreased due to the
lower real part of the radiated power. The input impedance resistance goes down from
Table 4. Lumped element model values for the s-shape and the bandwidth optimized s-shape designs.
values for the model in Figure 36. The equivalent circuit shows how stubs can be used to
tune the impedance in order to match to any IC. Parametric sweeps can be used along
Rs: antenna series resistance (due to metal effects) Ls : antenna series inductance (due to metal effects) RP : tag parallel resistance (due to substrate + metal effects) CP : tag parallel capacitance (due to substrate + metal effects) RS2 : resistive stub series resistance LS2 : resistive stub series inductance RP2 : resistive stub parallel resistance CP2 : resistive stub parallel capacitance CTag : capacitive coupling (CE, LCP // CE ,air)
78
different stubs structures (for example loops structures can be used for adding series
inductance or parallel capacitance). The resistance of the antenna is mainly determined
by the radiating body and can be tuned by the two stubs as shown above. This model also
helps to determine the amount of loss (as parallel resistance and capacitance) due to the
substrate loss which helps in understanding radiation efficiency as a function of the
substrate.
79
5.4 Summary
Maximum read range can be achieved when the dipole RFID antenna is half-
wavelength resonant and has direction of current flow that adds up constructively. The
tag size also plays a major role in determining the read range: The larger the tag, the
larger the energy capture area, therefore the longer the read range. One major difficulty in
RFID tag design is designing the matching network since the chips come with either high
loss. Pattern 2 test also showed that even if the tags are on one face and in close
proximity to each other almost each and every one of them can be read. Higher detection
can be successfully achieved by increasing the processing time.
6.2.1.2 Canyon (Waveguide) effect test
Patterns 2 (4 containers on F 2 at height 3) and 3 (column at corner of F 1 and F 2)
The last three tests that were conducted were to prove that waveguiding of the
plane waves occur by reading the tags in between containers. The reflection of the
propagating waves in between the containers creates the rectangular waveguide mode.
This channel effect as well as the instigation of surface waves (creepy waves) due to the
proximity of the traveling waves to conductive surface (containers) improves the
detection of the active tags. Even cellular phone that operates at 900 MHz was
receiving/transmitting full when tested along the corridors between the container stacks.
The height of the reader plays a major role for the detection: the higher the reader,
the further the reader can read. Although there is collision of the tags, 4 out of 5 tags
were read at 25ft and only 3 out of 5 at 8ft. This shows that the reader must be placed
higher at least 40ft or higher depending on further empirical test data. Here the trend is
important and is being proven. Canyon effect can be achieved when the reader is placed
high (i.e light posts) enough for the traveling wave to go through the container stacks.
Surface waves will also improve this. Another important point is that even if the tags
were positioned in the middle of or on the edges of the container surfaces, not much of
difference was observed. These two configurations seemed to behave the same way.
89
Anti-collision of tags in the reader processor is also a very important issue as well
as the coupling effect (electromagnetic interference of one tag on the other). It was also
observed that 5 min tests yielded better results than the 3 min tests. The reason is that the
probability of detection increases with increased time. This is intrinsic to the processor.
This is generic with all the test setups. Ample time is needed for the reader processor.
Recommended time is 7-10 min but the longer the time the better the readability of tags.
90
6.2 Summary
This conducted field study at the port of Savannah was of great benefit to realize
the challenges in such a harsh environment. Especially rugged metal containers create
increased level of difficulty for RFID tag detection. In order to improve the performance
of the active RFID system and implement it successfully, the following steps must be
taken into account:
1) The readers must be positioned higher than 30 feet. Putting the readers on the light
posts (~90 feet) could solve this problem depending how far they are from the
container stacks.
2) The readers have to be positioned pointing downwards and radiation pattern should
be changed from omni-directional to directional utilizing reflectors as shown below
in Figure 44. Beta angle can be made smaller (i.e. Beta from 60 degrees to 45
degrees) to control the directionality of the reader. The general trend is the smaller
the angle, the smaller the beamwidth, the more directional the reader becomes. If the
reader becomes more directional, more power gain is achieved. This results in higher
read range and detection probability. When two readers are positioned next to each
Figure 44. Top view of the reader and reflector position for active 915 MHz UHF RFID system.
91
other, with this configuration least amount of electromagnetic coupling between the
readers will be accomplished. This will lead to overall RFID tag system performance
enhancement.
3) Multiple readers are needed to read the tags in different orientations. For instance, 2-
3 readers positioned equally in between the edges of of F1 and F2 at a level at least
higher than the maximum stack height (5 containers stacked up on top of each other)
is one possible way of achieving maximum detection. Reader synchronization can
be utilized for readers that are close to each other.
4) Processing time of 7-10 min is required for anti-collision avoidance. If system can
handle longer time, that is more preferred.
5) The distance of the readers from the edge of the containers is also critical. By
moving the reader far away from the metal will minimize the reception of reflected
power at the reader. This needs to be tested empirically.
6) Even if the tags were placed side by side (pattern 2) or one after the other (canyon
effect), the tags were detected almost completely.
7) With this type of reader orientation, pattern 5 configuration seems to be the best
solution for the detection. When the tags are placed on the edges, canyon effect
detection will also be maximized.
92
CHAPTER 7
CONCLUSIONS
The main objective of this thesis has been to develop and optimize RFID antennas
for passive 13.56 MHz HF and 915 MHz UHF tags as well as understanding the effects
of harsh environments on active 915 MHz UHF RFID technology. The popularity of
these two bands have shown that optimization techniques will be of great interest in the
various different RFID applications from inventory control to container tracking.
The miniaturization technique of using two inductors connected serially for 13.56
MHz HF tags can be utilized for even lower 125 kHz range. This technique can be used
as long as the fact that substrate material loss is not neglected. Further improvement in
near-field radiation can also be achieved with substrates that have magnetic properties by
embedding ferrite particles in the substrate. This is beneficial for both radiation
optimization and size reduction.
Passive tags that operate in the passive UHF range usually suffer from poor
impedance matching at the antenna-IC interface. The ICs come in with different
impedances. This is one of the greatest challenges when designing the antenna for such
IC. This thesis showed that the resistive stub and double inductive stub techniques can
accomplish conjugate matching to any IC input impedance. Antenna’s radiation
properties are also critical for the UHF band since the environmental interference (i.e.
metals, liquids, human body absorption) affect more this band than the HF or lower
bands. This requires the designer to enhance antenna radiation characteristics such as
radiation pattern, radiation efficiency and gain by improving the current flow on the
93
antenna. The loss in the medium sometimes cannot be controlled, so optimum
performance must be attained as discussed in previous chapters.
Even the active tags undergo similar challenges from the environment
surrounding the tag-reader system. The conducted field study at the port of Savannah,
GA has revealed that one must comprehend the obstacles from a higher system point of
view not only at the lower tag design level. The problematic interaction between the
reader and the tag presents the real complication to a successfully operating RFID
application.
In RFID technology every application comes with different and sometimes unique
challenges. In today’s world transfer of information is increasing day by day. The same
pattern is repeated with the RFID technology. The need to gather more information and
store demands higher data rates and storage capacities. Integration of tags with other
active modules such as sensors (i.e. temperature, pressure) with batteries has caught a lot
of attention lately. This means greater challenges are imminent in terms of packaging
constraints and frequency limitations.
94
APPENDIX A
LIST OF PUBLICATIONS
[1] S. S. Basat, S. Bhattacharya, Li Yang, A. Rida, M. M. Tentzeris, J. Laskar, “Design of a Novel High-Efficiency UHF RFID Antenna on Flexible LCP Substrate with High Read-Range Capability”, Proc. of the 2006 IEEE-APS Symposium Albuquerque, AZ, July 2006.
[2] S. Basat, S. Bhattacharya, A. Rida, S. Johnston, L. Yang, M.M. Tentzeris, J. Laskar, “Fabrication and Assembly of a Novel High-Efficiency UHF RFID Tag on Flexible LCP Substrate”, Proc. of the 2006 IEEE-ECTC Symposium San Diego,CA, May 2006.
[3] Li Yang, Serkan Basat, Amin Rida, M.M. Tentzeris, “Design and Development of Novel Miniaturized UHF RFID Tags on Ultra-low-cost Paper-based Substrates”, 2007 IEEE-APMC Conference Thailand, Bangkok Dec 2007.
[4] Antonio Ferrer-Vidal, Amin Rida, Serkan Basat, Li Yang, M.M. Tentzeris “Integration of Sensors and RFIDs on Ultra-low-cost Paper-based Substrates for Wireless Sensors Networks Applications”, 2006 IEEE-SECON Conference Reston,VA, Sep 2006.
[5] RongLin Li, S. Basat, J. Laskar, and M. M. Tentzeris, “Development of wideband circularly polarized square- and rectangular-loop antennas”, 2006 IEE Proc. Microwaves, Antennas & Propagation , Jan. 2006.
[6] S.S.Basat, K.Lim, J.Laskar and M.M.Tentzeris, "Design and Modeling of Embedded 13.56 MHz RFID Antennas" , Procs. of the 2005 IEEE-APS Symposium, pp.64-67, vol.4B, Washington, DC, July 2005.
[7] S.Basat, K.Lim, I.Kim, J.Laskar, M.M.Tentzeris, Y.Kim, S.Lim and B.Chung, “Design and Development of a Miniaturized Embedded UHF RFID Tag for Automotive Tire Applications”, Procs. of the 2005 IEEE-ECTC Symposium , pp.867-870, Orlando, FL, June 2005.
[8] N.Bushyager, L.Martin, S.Khushrushahi, S.Basat and M.M.Tentzeris, “Design of RF and Wireless Packages Using Fast Hybrid Electromagnetic/Statistical Methods”, Proc. of the 2003 IEEE-ECTC Symposium, pp.1546-1549, New Orleans, LA, May 2003.
95
APPENDIX B
PORT OF SAVANNAH FIELD TEST SET-UP AND TABULATED
DATA
Pattern 5 (5 containers on ground level on Face 1) TAG POSITION Container Number Bay Position Height 1 2 3 4 HLUX 221126-2 59 1 1 1814 13C9 137E 137CHLUX 316405-7 61 1 1 1832 135A 1148 136EZCSU 811148-5 64 1 1 136F 1360 138E 13B2CLHU 851935-5 68 1 1 FEC F4E 134E ECO HLXU 452424-5 72 1 1 F4B 1097 133F 13A6 See Test Plan in Figure 32 for illustration of tag positions for each pattern. Face 1 of our stack is the side where pattern 4 and 5 containers are positioned. Face 2 of our stack is the end where pattern 2 containers are positioned Face 3 of our stack is the face opposite Face 1. Face 4 of our stack is opposite Face 2. The Bay 59 is the bay where containers on Face 2 are stacked. Bay 61 is the second row of containers moving back from Face 2 Bay 64 is the third row of container moving back from Face 2 Bay 68 is the fourth row of containers moving back from Face 2 Bay 72 is the fifth row of containers moving back from Face 2 Position 1 is the first row of containers on Face 1 Position 2 is the second row of containers moving back from Face 1 Position 3 is the third row of containers moving back from Face 1 Position 4 is the fourth row of containers moving back from Face 1 Position 5 is the fifth row of containers moving back from Face 1 Height 1 is the ground level container in any stack. Height 2, 3, 4, 5, etc are respectively moving higher in any stack Container are positioned by the Bay number, the position number, and the height number. Pattern 4 (5 containers in #2 height onFace 1) TAG POSITION Container Number Bay Position Height 1 2 3 4 COPU 236440-2 59 1 2 1821 1344 1397 1813HLXU 260561-0 61 1 2 None 17FD 13BE 684 TCKU 934866-2 64 1 2 11D5 1817 F45 1346TCKU 966695-6 68 1 2 13AB 13AF 10BD 183DHLXU 457117-0 72 1 2 1809 1190 1391 1027
96
Pattern 3 (Column at corner of Face 1 and 2) TAG POSITION Container Number Bay Position Height 1 2 3 4 HLXU 221126-2 59 1 1 182D 1838 180B NONECOPU 236440-2 59 1 2 1821 1344 1397 1813NYKU 257254-0 59 1 3 1133 1833 13BF 1821TTNU 335697-1 59 1 4 1343 1820 1803 1133TTNU 198038-2 59 1 5 1021 1340 1366 1343 Pattern 2 (5 containers across Face 2 at height 3) TAG POSITION Container Number Bay Position Height 1 2 3 4 NYKU 257254-0 59 1 3 182D 182E 13A7 13C! PONU 018719-7 59 2 3 1352 ECF 1810 1369NYKU 263405-0 59 3 3 1379 1361 13B7 13A2NYKU 256927-4 59 4 3 1373 1356 17FA 1364TTNU 318245-8 59 5 3 13BO 137F 1348 13A1 Pattern 1 ( container stack in the middle at Bay 64, Position 3) TAG POSITION Container Number Bay Position Height 1 2 3 4 TTNU 583003-5 64 3 1 17F9 13A8 11A8 NONEGATU 861360-4 64 3 2 13AD 13C8 136D 13A9TCKU 931425-6 64 3 3 17FE 138D 1837 1385TCNU 954041-1 64 3 4 927 133E 6A1 13B6TRIU 968716-4 64 3 5 1384 13CB F22 1819 Containers in Yellow were moved before test. They were in the stack, but location unknown) Container COPU 236440-2 in 59,1,2 in both patterns 3 & 4 with identical tag placement (tags shown twice) Container HLXU 221126-2 in 59,1,1 in both patterns 3 & 5 with different tag placements (7 total tags) Container NYKU 257254-0 in 59,1,3 in both pattern 2 & 3 with different tag placements (8 total tags) Some tag numbers are shown twice when they represent both the top of one container and bottom of another.
Table 5. Active UHF RFID Test set-up for container tracking and tag positions.
3:30:15 measured location 5 halfway at 0 degrees, 8 feet. 3:39:50 measured location 5 at the edge at 0 degrees, 8 feet. 3:59:00 measured location 5 at the edge at 0 degrees, 16 feet. Second Test (performed on face F2) In this test, all measurements were taken on the middle gap, with three stacks of containers on each side. 40 feet away from the containers:
98
4:13 PM height was 8 feet. 20 feet away from the containers: 4:20 PM height was 8 feet. at the edge of the containers: 4:28 PM 8 feet 4:38 PM 16' 7'' 4:54:25 25' 1'' Third Test (performed on face F4) All measurements taken on the middle gap and at the edge of the containers. 5:24 PM 25' 1'' 5:34 PM 16' 7'' 5:44 PM 8 feet
Table 6. Active UHF RFID Conducted field test with the times.
99
Face F4 10
1 1 4
4 0
0
9
1 1 2
1 1
4
8
1
1 1 0
0 0
0
7 third test here
3 0 1
1 4
4
Face F1
6
Face
F3
100
2 0 3
3 3
3
5
40 fe
et
2 5 5
5 4
0
4 20
feet
2 5 5
5 2
0
3 20
feet
4 1 4
4 4
2
2 second test performed here
40 fe
et
1 0 degrees ------>
Face F2
Figure 39. Containers in the stack positioned during the day of the measurement for the active 915 MHz UHF RFID field test.
101
This test was performed at 8', 16', and 25' 4'' This test was only performed at 25' 4''
4
4 4
4
2
1 2
1
0
0 0
0
ECO was replaced by F4E
ECO
1
1 1
F4E
1
3 3 3 3
102
134E
134E
13A6
5
5 5
13A6
5
1097
5
5 5 1097
5
0F4B
4
4 4 0F4B
4
Figure 40. Canyon effect (Waveguiding) case active 915 MHz UHF RFID test set-up for container tracking.
103
Tag-ID Container Number Bay Position Height TAG POSITION Pattern Location
1 8FT Location 1 16FT
Location 1 25FT
Location 2 8FT
Location 2 16FT
Location 2 25FT
Location 3 8FT
Location 3 16FT
001814 HLUX 221126-2
59 1 1 1 5 x x x x x x x x
0013C9 HLUX 221126-2
59 1 1 2 5 x x x
00137E HLUX 221126-2
59 1 1 3 5 x x x x x x x
00137C HLUX 221126-2
59 1 1 4 5 x x x x x x x x
001832 HLUX 316405-7
61 1 1 1 5 x x x x x x x x
00135A HLUX 316405-7
61 1 1 2 5 x x x x
001148 HLUX 316405-7 61 1 1 3 5
00136E HLUX 316405-7
61 1 1 4 5 x x x x x x x x
00136F ZCSU 811148-5
64 1 1 1 5 x x x x x x
001360 ZCSU 811148-5
64 1 1 2 5 x
00138E ZCSU 811148-5
64 1 1 3 5 x x x x x
0013B2 ZCSU 811148-5
64 1 1 4 5 x x x x x x x x
000FEC CLHU 851935-5
68 1 1 1 5
000F4E CLHU 851935-5
68 1 1 2 5
00134E CLHU 851935-5
68 1 1 3 5 x x
000EC0 CLHU 851935-5
68 1 1 4 5 x x x x
000F4B HLXU 452424-5
72 1 1 1 5 x
001097 HLXU 452424-5 72 1 1 2 5
00133F HLXU 452424-5
72 1 1 3 5 x x x
0013A6 HLXU 452424-5
72 1 1 4 5 x x x x x x x
001821 COPU 236440-2 59 1 2 1 4
001344 COPU 236440-2
59 1 2 2 4 x x x
001397 COPU 236440-2
59 1 2 3 4 x x x x x x x x
001813 COPU 236440-2 59 1 2 4 4
No TAG HLXU 260561-0
61 1 2 1 4
0017FD HLXU 260561-0
61 1 2 2 4 x x x x
0013BE HLXU 260561-0
61 1 2 3 4 x x x x x x x
000684 HLXU 260561-0 61 1 2 4 4
0011D5 TCKU 934866-2
64 1 2 1 4
001817 TCKU 934866-2
64 1 2 2 4
000F45 TCKU 934866-2
64 1 2 3 4 x x
001346 TCKU 934866-2 64 1 2 4 4
0013AB TCKU 966695-6
68 1 2 1 4
0013AF TCKU 966695-6
68 1 2 2 4
104
0010BD TCKU 966695-6
68 1 2 3 4
00183D TCKU 966695-6
68 1 2 4 4 x x
001809 HLXU 457117-0 72 1 2 1 4
001190 HLXU 457117-0 72 1 2 2 4
001391 HLXU 457117-0
72 1 2 3 4 x x
001027 HLXU 457117-0 72 1 2 4 4
001821 COPU 236440-2 59 1 2 1 3
001344 COPU 236440-2
59 1 2 2 3 x x x
001397 COPU 236440-2
59 1 2 3 3 x x x x x x x x
001813 COPU 236440-2 59 1 2 4 3
00182D HLXU 221126-2
59 1 1 1 3 x x x x x
001838 HLXU 221126-2
59 1 1 2 3 x x x
00180B HLXU 221126-2
59 1 1 3 3 x x x x x x x x
No TAG HLXU 221126-2
59 1 1 4 3
001133 NYKU 257254-0 59 1 3 1 3
001833 NYKU 257254-0
59 1 3 2 3 x x x x x x
0013BF NYKU 257254-0
59 1 3 3 3 x x x x x x x x
001821 NYKU 257254-0 59 1 3 4 3
001021 TTNU 198038-2 59 1 5 1 3
001340 TTNU 198038-2 59 1 5 2 3
001366 TTNU 198038-2
59 1 5 3 3 x
001343 TTNU 198038-2 59 1 5 4 3
001343 TTNU 335697-1 59 1 4 1 3
001820 TTNU 335697-1 59 1 4 2 3
001803 TTNU 335697-1
59 1 4 3 3 x
001133 TTNU 335697-1 59 1 4 4 3
001373 NYKU 256927-4
59 4 3 1 2 x x
001356 NYKU 256927-4
59 4 3 2 2 x x x
0017FA NYKU 256927-4
59 4 3 3 2 x x x
001364 NYKU 256927-4 59 4 3 4 2
00182D NYKU 257254-0
59 1 3 1 2 x x x x x
00182E NYKU 257254-0
59 1 3 2 2 x x x x x
0013A7 NYKU 257254-0
59 1 3 3 2 x x x x x x
0013C1 NYKU 257254-0
59 1 3 4 2 x x x x x x
001379 NYKU 263405-0
59 3 3 1 2 x x
001361 NYKU 263405-0
59 3 3 2 2 x x x x
0013B7 NYKU 263405-0
59 3 3 3 2 x x x
0013A2 NYKU 263405-0
59 3 3 4 2 x x x
105
001352 PONU 018719-7
59 2 3 1 2 x x x
000ECF PONU 018719-7
59 2 3 2 2 x x
001810 PONU 018719-7
59 2 3 3 2 x x x
001369 PONU 018719-7
59 2 3 4 2 x x x x
0013B0 TTNU 318245-8
59 5 3 1 2 x
00137F TTNU 318245-8
59 5 3 2 2 x x
001348 TTNU 318245-8
59 5 3 3 2 x
0013A1 TTNU 318245-8 59 5 3 4 2 x x
0013AD GATU 861360-4 64 3 2 1 1
0013C8 GATU 861360-4 64 3 2 2 1
00136D GATU 861360-4 64 3 2 3 1
0013A9 GATU 861360-4
64 3 2 4 1
0017FE TCKU 931425-6
64 3 3 1 1 x
00138D TCKU 931425-6 64 3 3 2 1
001837 TCKU 931425-6 64 3 3 3 1
001385 TCKU 931425-6 64 3 3 4 1
000927 TCNU 954041-1 64 3 4 1 1
00133E TCNU 954041-1 64 3 4 2 1
0006A1 TCNU 954041-1 64 3 4 3 1
0013B6 TCNU 954041-1
64 3 4 4 1
001384 TRIU 968716-4 64 3 5 1 1
0013CB TRIU 968716-4 64 3 5 2 1
000F22 TRIU 968716-4 64 3 5 3 1
001819 TRIU 968716-4 64 3 5 4 1
0017F9 TTNU 583003-5 64 3 1 1 1
0013A8 TTNU 583003-5 64 3 1 2 1
0011A8 TTNU 583003-5 64 3 1 3 1
No TAG TTNU 583003-5
64 3 1 4 1
106
Tag-ID Container Number Bay Position Height TAG POSITION Pattern Location
3 25FTLocation
4 8FT Location 4 16FT
Location 4 25FT
Location 5 8FT
Location 5 16 FT
Location 5 25FT
Location 6 8FT
001814 HLUX 221126-2
59 1 1 1 5 x x x x x x x x
0013C9 HLUX 221126-2
59 1 1 2 5 x x x
00137E HLUX 221126-2
59 1 1 3 5 x x x
00137C HLUX 221126-2
59 1 1 4 5 x x x x x
001832 HLUX 316405-7
61 1 1 1 5 x x x x x x x x
00135A HLUX 316405-7
61 1 1 2 5 x x x x x x
001148 HLUX 316405-7 61 1 1 3 5
00136E HLUX 316405-7 61 1 1 4 5 x x x x x x x x
00136F ZCSU 811148-5 64 1 1 1 5 x x x x x x x x
001360 ZCSU 811148-5
64 1 1 2 5 x x x x x x x
00138E ZCSU 811148-5
64 1 1 3 5 x x x x x x x x
0013B2 ZCSU 811148-5
64 1 1 4 5 x x x x x x x x
000FEC CLHU 851935-5
68 1 1 1 5 x
000F4E CLHU 851935-5
68 1 1 2 5 x
00134E CLHU 851935-5
68 1 1 3 5 x x x x x x x
000EC0 CLHU 851935-5
68 1 1 4 5 x x x x x x x x
000F4B HLXU 452424-5
72 1 1 1 5 x x
001097 HLXU 452424-5 72 1 1 2 5
00133F HLXU 452424-5
72 1 1 3 5 x x x x x
0013A6 HLXU 452424-5
72 1 1 4 5 x x x x x x x
001821 COPU 236440-2 59 1 2 1 4
001344 COPU 236440-2
59 1 2 2 4 x
001397 COPU 236440-2
59 1 2 3 4 x x x x x x x x
001813 COPU 236440-2 59 1 2 4 4
No TAG HLXU 260561-0
61 1 2 1 4
0017FD HLXU 260561-0
61 1 2 2 4 x x
0013BE HLXU 260561-0
61 1 2 3 4 x x x x x x x x
000684 HLXU 260561-0 61 1 2 4 4
0011D5 TCKU 934866-2
64 1 2 1 4 x x x x
001817 TCKU 934866-2
64 1 2 2 4 x x x x x
000F45 TCKU 934866-2
64 1 2 3 4 x x x x x x x x
001346 TCKU 934866-2 64 1 2 4 4
0013AB TCKU 966695-6
68 1 2 1 4 x x x
0013AF TCKU 966695-6
68 1 2 2 4 x x
0010BD TCKU 966695-6
68 1 2 3 4 x x x x
00183D TCKU 966695-6
68 1 2 4 4 x x x
107
001809 HLXU 457117-0 72 1 2 1 4
001190 HLXU 457117-0 72 1 2 2 4
001391 HLXU 457117-0
72 1 2 3 4 x x x x x x
001027 HLXU 457117-0 72 1 2 4 4
001821 COPU 236440-2 59 1 2 1 3
001344 COPU 236440-2
59 1 2 2 3 x
001397 COPU 236440-2
59 1 2 3 3 x x x x x x x x
001813 COPU 236440-2 59 1 2 4 3
00182D HLXU 221126-2
59 1 1 1 3
001838 HLXU 221126-2
59 1 1 2 3 x x
00180B HLXU 221126-2
59 1 1 3 3 x x x x x x x x
No TAG HLXU 221126-2
59 1 1 4 3
001133 NYKU 257254-0 59 1 3 1 3
001833 NYKU 257254-0
59 1 3 2 3 x x x x x
0013BF NYKU 257254-0
59 1 3 3 3 x x x x x x x x
001821 NYKU 257254-0 59 1 3 4 3
001021 TTNU 198038-2 59 1 5 1 3
001340 TTNU 198038-2 59 1 5 2 3
001366 TTNU 198038-2
59 1 5 3 3
001343 TTNU 198038-2 59 1 5 4 3
001343 TTNU 335697-1 59 1 4 1 3
001820 TTNU 335697-1 59 1 4 2 3
001803 TTNU 335697-1
59 1 4 3 3
001133 TTNU 335697-1 59 1 4 4 3
001373 NYKU 256927-4
59 4 3 1 2
001356 NYKU 256927-4
59 4 3 2 2
0017FA NYKU 256927-4
59 4 3 3 2
001364 NYKU 256927-4 59 4 3 4 2
00182D NYKU 257254-0
59 1 3 1 2
00182E NYKU 257254-0
59 1 3 2 2
0013A7 NYKU 257254-0
59 1 3 3 2
0013C1 NYKU 257254-0
59 1 3 4 2
001379 NYKU 263405-0
59 3 3 1 2
001361 NYKU 263405-0
59 3 3 2 2
0013B7 NYKU 263405-0
59 3 3 3 2
0013A2 NYKU 263405-0
59 3 3 4 2
001352 PONU 018719-7
59 2 3 1 2
000ECF PONU 018719-7
59 2 3 2 2
108
001810 PONU 018719-7
59 2 3 3 2
001369 PONU 018719-7
59 2 3 4 2 x
0013B0 TTNU 318245-8
59 5 3 1 2
00137F TTNU 318245-8
59 5 3 2 2
001348 TTNU 318245-8
59 5 3 3 2
0013A1 TTNU 318245-8
59 5 3 4 2
0013AD GATU 861360-4
64 3 2 1 1 x
0013C8 GATU 861360-4 64 3 2 2 1
00136D GATU 861360-4 64 3 2 3 1
0013A9 GATU 861360-4
64 3 2 4 1 x
0017FE TCKU 931425-6
64 3 3 1 1 x x x x
00138D TCKU 931425-6 64 3 3 2 1
001837 TCKU 931425-6 64 3 3 3 1
001385 TCKU 931425-6 64 3 3 4 1
000927 TCNU 954041-1 64 3 4 1 1
00133E TCNU 954041-1 64 3 4 2 1
0006A1 TCNU 954041-1 64 3 4 3 1
0013B6 TCNU 954041-1
64 3 4 4 1 x
001384 TRIU 968716-4 64 3 5 1 1
0013CB TRIU 968716-4 64 3 5 2 1
000F22 TRIU 968716-4 64 3 5 3 1
001819 TRIU 968716-4 64 3 5 4 1
0017F9 TTNU 583003-5 64 3 1 1 1
0013A8 TTNU 583003-5 64 3 1 2 1
0011A8 TTNU 583003-5 64 3 1 3 1
No TAG TTNU 583003-5
64 3 1 4 1
109
Tag-ID Container Number Bay Position Height TAG POSITION Pattern Location
6 16FT Location 6 25FT
Location 7 8FT
Location 7 16FT
Location 7 25FT
Location 8 8FT
Location 8 16FT
Location 8 25FT
001814 HLUX 221126-2
59 1 1 1 5 x x x x
0013C9 HLUX 221126-2
59 1 1 2 5
00137E HLUX 221126-2
59 1 1 3 5 x
00137C HLUX 221126-2
59 1 1 4 5 x x
001832 HLUX 316405-7
61 1 1 1 5 x x x x x x x x
00135A HLUX 316405-7
61 1 1 2 5 x
001148 HLUX 316405-7 61 1 1 3 5
00136E HLUX 316405-7 61 1 1 4 5 x x x x x x x x
00136F ZCSU 811148-5 64 1 1 1 5 x x x x x x x x
001360 ZCSU 811148-5
64 1 1 2 5 x x x x
00138E ZCSU 811148-5
64 1 1 3 5 x
0013B2 ZCSU 811148-5
64 1 1 4 5 x x x x x x x x
000FEC CLHU 851935-5
68 1 1 1 5 x x x
000F4E CLHU 851935-5
68 1 1 2 5
00134E CLHU 851935-5
68 1 1 3 5 x x x
000EC0 CLHU 851935-5
68 1 1 4 5 x x x
000F4B HLXU 452424-5
72 1 1 1 5 x x x x x
001097 HLXU 452424-5 72 1 1 2 5
00133F HLXU 452424-5
72 1 1 3 5 x x x x x x x
0013A6 HLXU 452424-5
72 1 1 4 5 x x x x x x x
001821 COPU 236440-2 59 1 2 1 4
001344 COPU 236440-2
59 1 2 2 4 x
001397 COPU 236440-2
59 1 2 3 4 x x x x x x
001813 COPU 236440-2 59 1 2 4 4
No TAG HLXU 260561-0
61 1 2 1 4
0017FD HLXU 260561-0
61 1 2 2 4
0013BE HLXU 260561-0
61 1 2 3 4 x x x x x x
000684 HLXU 260561-0 61 1 2 4 4
0011D5 TCKU 934866-2
64 1 2 1 4 x
001817 TCKU 934866-2
64 1 2 2 4 x
000F45 TCKU 934866-2
64 1 2 3 4
001346 TCKU 934866-2 64 1 2 4 4
0013AB TCKU 966695-6
68 1 2 1 4 x x x x
0013AF TCKU 966695-6
68 1 2 2 4 x x x x x x
0010BD TCKU 966695-6
68 1 2 3 4 x x x x
00183D TCKU 966695-6
68 1 2 4 4 x x
110
001809 HLXU 457117-0 72 1 2 1 4
001190 HLXU 457117-0 72 1 2 2 4
001391 HLXU 457117-0
72 1 2 3 4 x x x x x x x x
001027 HLXU 457117-0 72 1 2 4 4
001821 COPU 236440-2 59 1 2 1 3
001344 COPU 236440-2
59 1 2 2 3 x
001397 COPU 236440-2
59 1 2 3 3 x x x x x x
001813 COPU 236440-2 59 1 2 4 3
00182D HLXU 221126-2
59 1 1 1 3
001838 HLXU 221126-2
59 1 1 2 3
00180B HLXU 221126-2
59 1 1 3 3 x x x x x x x
No TAG HLXU 221126-2
59 1 1 4 3
001133 NYKU 257254-0 59 1 3 1 3
001833 NYKU 257254-0
59 1 3 2 3
0013BF NYKU 257254-0
59 1 3 3 3 x x x
001821 NYKU 257254-0 59 1 3 4 3
001021 TTNU 198038-2 59 1 5 1 3
001340 TTNU 198038-2 59 1 5 2 3
001366 TTNU 198038-2
59 1 5 3 3
001343 TTNU 198038-2 59 1 5 4 3
001343 TTNU 335697-1 59 1 4 1 3
001820 TTNU 335697-1 59 1 4 2 3
001803 TTNU 335697-1
59 1 4 3 3
001133 TTNU 335697-1 59 1 4 4 3
001373 NYKU 256927-4
59 4 3 1 2
001356 NYKU 256927-4
59 4 3 2 2
0017FA NYKU 256927-4
59 4 3 3 2
001364 NYKU 256927-4 59 4 3 4 2
00182D NYKU 257254-0
59 1 3 1 2
00182E NYKU 257254-0
59 1 3 2 2
0013A7 NYKU 257254-0
59 1 3 3 2
0013C1 NYKU 257254-0
59 1 3 4 2
001379 NYKU 263405-0
59 3 3 1 2
001361 NYKU 263405-0
59 3 3 2 2
0013B7 NYKU 263405-0
59 3 3 3 2
0013A2 NYKU 263405-0
59 3 3 4 2
001352 PONU 018719-7
59 2 3 1 2
000ECF PONU 018719-7
59 2 3 2 2
111
001810 PONU 018719-7
59 2 3 3 2
001369 PONU 018719-7
59 2 3 4 2
0013B0 TTNU 318245-8
59 5 3 1 2
00137F TTNU 318245-8
59 5 3 2 2
001348 TTNU 318245-8
59 5 3 3 2
0013A1 TTNU 318245-8
59 5 3 4 2
0013AD GATU 861360-4
64 3 2 1 1
0013C8 GATU 861360-4 64 3 2 2 1
00136D GATU 861360-4 64 3 2 3 1
0013A9 GATU 861360-4
64 3 2 4 1
0017FE TCKU 931425-6
64 3 3 1 1 x x x
00138D TCKU 931425-6 64 3 3 2 1
001837 TCKU 931425-6 64 3 3 3 1
001385 TCKU 931425-6 64 3 3 4 1
000927 TCNU 954041-1 64 3 4 1 1
00133E TCNU 954041-1 64 3 4 2 1
0006A1 TCNU 954041-1 64 3 4 3 1
0013B6 TCNU 954041-1
64 3 4 4 1 x
001384 TRIU 968716-4 64 3 5 1 1
0013CB TRIU 968716-4 64 3 5 2 1
000F22 TRIU 968716-4 64 3 5 3 1
001819 TRIU 968716-4 64 3 5 4 1
0017F9 TTNU 583003-5 64 3 1 1 1
0013A8 TTNU 583003-5 64 3 1 2 1
0011A8 TTNU 583003-5 64 3 1 3 1
No TAG TTNU 583003-5
64 3 1 4 1
112
Tag-ID Container Number Bay Position Height TAG POSITION Pattern Location
9 8FT Location 9 16FT
Location 9 25FT
Location 10 8FT
Location 10 16FT
Location 10 25FT
001814 HLUX 221126-2
59 1 1 1 5
0013C9 HLUX 221126-2
59 1 1 2 5
00137E HLUX 221126-2
59 1 1 3 5
00137C HLUX 221126-2
59 1 1 4 5
001832 HLUX 316405-7
61 1 1 1 5 x x x x x
00135A HLUX 316405-7
61 1 1 2 5
001148 HLUX 316405-7 61 1 1 3 5
00136E HLUX 316405-7 61 1 1 4 5 x x x x x x
00136F ZCSU 811148-5 64 1 1 1 5
001360 ZCSU 811148-5
64 1 1 2 5
00138E ZCSU 811148-5
64 1 1 3 5
0013B2 ZCSU 811148-5
64 1 1 4 5 x x x x x x
000FEC CLHU 851935-5
68 1 1 1 5
000F4E CLHU 851935-5
68 1 1 2 5
00134E CLHU 851935-5
68 1 1 3 5
000EC0 CLHU 851935-5
68 1 1 4 5
000F4B HLXU 452424-5
72 1 1 1 5 x x
001097 HLXU 452424-5 72 1 1 2 5
00133F HLXU 452424-5
72 1 1 3 5 x x
0013A6 HLXU 452424-5
72 1 1 4 5 x
001821 COPU 236440-2 59 1 2 1 4
001344 COPU 236440-2
59 1 2 2 4
001397 COPU 236440-2
59 1 2 3 4
001813 COPU 236440-2 59 1 2 4 4
No TAG HLXU 260561-0
61 1 2 1 4
0017FD HLXU 260561-0
61 1 2 2 4
0013BE HLXU 260561-0
61 1 2 3 4 x
000684 HLXU 260561-0 61 1 2 4 4
0011D5 TCKU 934866-2
64 1 2 1 4
001817 TCKU 934866-2
64 1 2 2 4
000F45 TCKU 934866-2
64 1 2 3 4
001346 TCKU 934866-2 64 1 2 4 4
0013AB TCKU 966695-6
68 1 2 1 4
0013AF TCKU 966695-6
68 1 2 2 4 x x
0010BD TCKU 966695-6
68 1 2 3 4
00183D TCKU 966695-6
68 1 2 4 4
113
001809 HLXU 457117-0 72 1 2 1 4
001190 HLXU 457117-0 72 1 2 2 4
001391 HLXU 457117-0
72 1 2 3 4 x x x x x x
001027 HLXU 457117-0 72 1 2 4 4
001821 COPU 236440-2 59 1 2 1 3
001344 COPU 236440-2
59 1 2 2 3
001397 COPU 236440-2
59 1 2 3 3
001813 COPU 236440-2 59 1 2 4 3
00182D HLXU 221126-2
59 1 1 1 3
001838 HLXU 221126-2
59 1 1 2 3
00180B HLXU 221126-2
59 1 1 3 3
No TAG HLXU 221126-2
59 1 1 4 3
001133 NYKU 257254-0 59 1 3 1 3
001833 NYKU 257254-0
59 1 3 2 3
0013BF NYKU 257254-0
59 1 3 3 3
001821 NYKU 257254-0 59 1 3 4 3
001021 TTNU 198038-2 59 1 5 1 3
001340 TTNU 198038-2 59 1 5 2 3
001366 TTNU 198038-2
59 1 5 3 3
001343 TTNU 198038-2 59 1 5 4 3
001343 TTNU 335697-1 59 1 4 1 3
001820 TTNU 335697-1 59 1 4 2 3
001803 TTNU 335697-1
59 1 4 3 3
001133 TTNU 335697-1 59 1 4 4 3
001373 NYKU 256927-4
59 4 3 1 2
001356 NYKU 256927-4
59 4 3 2 2
0017FA NYKU 256927-4
59 4 3 3 2
001364 NYKU 256927-4 59 4 3 4 2
00182D NYKU 257254-0
59 1 3 1 2
00182E NYKU 257254-0
59 1 3 2 2
0013A7 NYKU 257254-0
59 1 3 3 2
0013C1 NYKU 257254-0
59 1 3 4 2
001379 NYKU 263405-0
59 3 3 1 2
001361 NYKU 263405-0
59 3 3 2 2
0013B7 NYKU 263405-0
59 3 3 3 2
0013A2 NYKU 263405-0
59 3 3 4 2
001352 PONU 018719-7
59 2 3 1 2
000ECF PONU 018719-7
59 2 3 2 2
114
001810 PONU 018719-7
59 2 3 3 2
001369 PONU 018719-7
59 2 3 4 2
0013B0 TTNU 318245-8
59 5 3 1 2
00137F TTNU 318245-8
59 5 3 2 2
001348 TTNU 318245-8
59 5 3 3 2
0013A1 TTNU 318245-8
59 5 3 4 2
0013AD GATU 861360-4
64 3 2 1 1
0013C8 GATU 861360-4 64 3 2 2 1
00136D GATU 861360-4 64 3 2 3 1
0013A9 GATU 861360-4
64 3 2 4 1
0017FE TCKU 931425-6
64 3 3 1 1
00138D TCKU 931425-6 64 3 3 2 1
001837 TCKU 931425-6 64 3 3 3 1
001385 TCKU 931425-6 64 3 3 4 1
000927 TCNU 954041-1 64 3 4 1 1
00133E TCNU 954041-1 64 3 4 2 1
0006A1 TCNU 954041-1 64 3 4 3 1
0013B6 TCNU 954041-1
64 3 4 4 1
001384 TRIU 968716-4 64 3 5 1 1
0013CB TRIU 968716-4 64 3 5 2 1
000F22 TRIU 968716-4 64 3 5 3 1
001819 TRIU 968716-4 64 3 5 4 1
0017F9 TTNU 583003-5 64 3 1 1 1
0013A8 TTNU 583003-5 64 3 1 2 1
0011A8 TTNU 583003-5 64 3 1 3 1
No TAG TTNU 583003-5
64 3 1 4 1
Table 7. Overall active UHF RFID tags by location on the containers in the stack.
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