Mobile Apps with CEM for Teaching and Learning of
Electromagnetics
Mobile
Apps (Snapshots)
Apps on App Store: MuStripKit, EMpolarization, EMwaveRT
Apps
Video Demos
Several pre-set examples of linear
polarization for quick illustration.
The Ex and Ey components are animated by green
arrows on the xy plane and can be traced from the time-domain waveforms via
dashed green lines.
Several pre-set examples of circular
polarization for quick illustration.
The total E field vector is animated by a red
arrow, along with the trace of the E vector extremity (tip).
Several pre-set examples of elliptical
polarization for quick illustration.
The type of polarization can be deduced from the
trace of the E vector tip. E.g., the E vector tip traces out an ellipse,
indicating an elliptical polarization.
Users may input various wave parameters (using
keyboard or slider) to see the change in real
time
in the polarization ellipse and/or handedness.
The electric field expressions in the time
domain
and phasor form are
Several pre-set examples of linear
polarization states illustrated on Poincare sphere as earth globe (by
tapping on the “More” button at the top-right corner).
Linear polarization states are always
represented on the equator.
Several pre-set examples of circular
polarization states illustrated on Poincare sphere as earth globe.
The north and south poles represent circular
polarization states with left and right handedness respectively.
Several pre-set examples of elliptical polarization
states illustrated on Poincare sphere as earth globe.
Elliptical polarization states are represented
by the locations other than equator, North and South Poles.
The upper and lower hemispheres correspond to
left- and right-handed elliptical polarizations respectively.
Users may change the polarization arbitrarily
and see the red ball rolling on Poincare sphere as earth globe.
Have fun to roll the red ball around and find out
the polarization corresponding to any place of interest!
More video
demos to be added …
Apps
Descriptions
MuStripKit is a versatile microstrip toolkit app
for microstrip circuit analysis and design. The app realizes various
functions, including microstrip line analysis and synthesis, calculations
of input impedance, reflection coefficient, and frequency response in terms
of S-parameters. A Smith chart tool is also provided to aid in designing a
microstrip circuit. In addition, using a novel multiple 1-D FDTD method,
the app shows time-domain simulation of microstrip circuits incorporated
with lumped elements, including resistors, capacitors, and inductors in
parallel, as well as series connections. Several educational circuit
examples are provided to help illustrate the electromagnetic wave
propagation in the microstrip circuit. For more information, please refer
to "A Microstrip Circuit Tool Kit App with FDTD Analysis Including
Lumped Elements," IEEE Microwave Magazine, vol. 16, no. 1, pp. 74-80,
2015, and “M1-D FDTD Methods for Mobile Interactive Teaching and Learning
of Wave Propagation in Transmission Lines,” IEEE Antennas and Propagation
Magazine, vol. 61, no. 5, pp. 119-126, 2019.
User interface:
- touch on number field to input/change value
- slider may be used to change value
- swipe left/right to select circuit element
- press 'Add'/'Del' to add/delete circuit
element in schematic
- tap to select circuit element in schematic
- long press to move circuit element in
schematic
EMpolarization is an app to aid teaching and
learning of electromagnetics (EM) using mobile devices on the topic of wave
polarization. The app is designed to provide interactive visualization to
help students better understand wave polarization concepts. Through the use
of the app, various polarizations could be explained better with the aid of
2D and 3D animations. Users are allowed to input various wave parameters to
see the change in real time in the polarization ellipse and/or handedness.
More advanced topics such as polarization ellipse parameters, Poincare
sphere and Stokes parameters are also presented. For more graphical
interaction with fun, the polarization state is further presented as a
point located on Poincare sphere that coincides with the earth globe. For
more information, please refer to the article "Teaching and Learning
Electromagnetic Polarization using Mobile Devices," IEEE Antennas and
Propagation Magazine, vol. 60, no. 4, pp. 112-121, 2018.
User interface:
- 3D view may be zoomed or rotated
- double tap to revert to default view
- touch on any underlined field to input/change
value
- use long slider to change the last field
touched
- use short slider to change animation speed
- press 'Linear/Circular/Elliptical' for preset
examples
- press ‘More’ to switch views
EMwaveRT is an app to aid teaching and learning
of electromagnetics (EM) using mobile devices on the topic of plane wave
reflection (R) and transmission (T). The app is designed to provide effective
touch-based interactivity and visualization to help students better
understand EM concepts. It is applicable to EM plane wave reflection and
transmission for general oblique incidence and polarization. The instructor
is able to input or change various parameters and rotate the view angles
for interactive teaching. Based on the parameters, the 3D animations of
incident, reflected and transmitted waves can be visualized in real time.
This allows the students to identify clearly each wave and improves their
learning of plane wave reflection and transmission. Through several preset
cases of incident angles, the visualizations on mobile devices are
illustrated. The app can be used to supplement the 3D TV program available
for download from here.
For more information, please refer to the article “Teaching and
Learning Electromagnetic Plane Wave Reflection and Transmission using 3D
TV,” IEEE Antennas and Propagation Magazine, vol. 61, no. 2, pp. 101-108,
2019.
User interface:
- 3D view may be zoomed or rotated
- text view may be zoomed or scrolled
- double tap to revert to default view
- touch on any underlined field to input/change
value
- use long slider to change the last field
touched
- use short slider to change the text
transparency
- use '|' to show/hide tangential components at
interface
Microstrip configuration setup for
circuit design and analysis
Circuit components selection (including
transmission lines and lumped elements),
parameters setting,
schematic construction
Smith chart, input impedance and
input reflection coefficient
Frequency responses (S parameters)
Real-time simulations using explicit FDTD.
Real-time simulations using Fundamental
ADI-FDTD, allowing time step size larger than CFL stability limit
(CFLN>1). This means one could “fast-forward” simulations, which will
still be stable for FADI (but unstable for conventional explicit FDTD).
Real-time simulations using Fundamental
ADI-FDTD, allowing time step size larger than CFL stability limit
(CFLN>1). This is for branch-line coupler example showing through,
coupled and isolated port responses.
Real-time simulations using Fundamental ADI-FDTD,
allowing time step size larger than CFL stability limit (CFLN>1). This
is for directional coupler example showing through, coupled and isolated
port responses.
Real-time simulations using Fundamental
ADI-FDTD, allowing time step size larger than CFL stability limit
(CFLN>1). This is for coupled-line filter making use of general even/odd
mode coupled-line differential equations (which are different from ordinary
Maxwell equations). It allows ‘fast-forwardable’ simulations and insightful
visualizations of resonating and coupling mechanisms in the filter
responses.
Electromagnetic wave
polarization:
components decompositions,
expressions
and 3D animation
Electromagnetic wave polarization:
ellipse parameters, Poincare
sphere,
Stokes parameters
Electromagnetic plane wave
reflection and transmission for general (oblique) incidence and
polarization
– on iPad/iPhone
– for rotatable 3D view of
Electromagnetic plane wave
reflection and transmission for general (oblique) incidence and
polarization
