2-D Beam-switching Waveguide Butler MatrixHirokawa
laboratory
Dept. of Electrical and Electronic Engineering, Tokyo Institute
of Technology2-12-1-S3-19, O-okayama, Meguro-ku, Tokyo, 152-8552
Japan
Configuration
Gain patterns and beam-directions on hemisphere
Proposed 42×42-way one-body 2-D beam-switching hollow waveguide
Butler matrix
Measurement Performances
Short-slot 2-plane Coupler
@22 GHzGain (dBi) 15.3±2.2SLL (dB) 7.3±3.0IL (dB)
0.60±0.07*Coverage (sr) 0.12±0.01
*-3.9 dB
Perspective view
The number and the symbol Xindicate the input port number and
the beam-direction
TE10-likemode
TE20-likemode
TM21-likemode
TM11-likemode
± : The polarity of field at output portRed arrows are
simplified field lines
• Operation of 2-plane Couplers
• Structures and Propagation Modes
Far-field measurement Near-field measurement
Coupled region (A-A’)
2-plane hybrid couplerInput
Input
Output
Output
𝑇𝑇𝐻𝐻 =12
1 −𝑗𝑗−𝑗𝑗 1
−𝑗𝑗 −1−1 −𝑗𝑗
−𝑗𝑗 −1−1 −𝑗𝑗
1 −𝑗𝑗−𝑗𝑗 1
𝑇𝑇𝐶𝐶 =0 00 0
0 11 0
0 11 0
0 00 0
Whole input power passes through 2 dimensionally
A quarter of input power with90° difference to neighbors
�𝑙𝑙2𝛽𝛽𝑇𝑇𝑇𝑇10 − 𝛽𝛽𝑇𝑇𝑇𝑇21 =
𝜋𝜋2
𝑙𝑙2𝛽𝛽𝑇𝑇𝑇𝑇10 − 𝛽𝛽𝑇𝑇𝑇𝑇20 =
𝜋𝜋4
�𝑙𝑙2𝛽𝛽𝑇𝑇𝑇𝑇10 − 𝛽𝛽𝑇𝑇𝑇𝑇21 = 𝜋𝜋
𝑙𝑙2𝛽𝛽𝑇𝑇𝑇𝑇10 − 𝛽𝛽𝑇𝑇𝑇𝑇20 =
𝜋𝜋2
Design conditions for2-plane hybrid coupler
Design conditions for2-plane cross coupler
Design conditions forboth couplers
�𝛽𝛽𝑇𝑇𝑇𝑇20 = 𝛽𝛽𝑇𝑇𝑇𝑇11
𝛽𝛽𝑇𝑇𝑇𝑇20 =𝛽𝛽𝑇𝑇𝑇𝑇𝑇𝑇+𝛽𝛽𝑇𝑇𝑇𝑇𝑇𝑇
2
Hybrid Mode Matching / Finite Element Method
A B
C
Analysis structureOverall structure
Input waveguides
Coupled region
One-eighth model
Output waveguides
Input waveguide
Coupled region : Numerical solution by FEMInput waveguide
:Analytical solution
Input waveguide
Discontinuousplane
Coupled region
PEC/PMC
2-plane cross coupler
Symmetrical plane A Cascade connection of S-matrix Symmetrical
plane B,C Place PEC or PMC walls
1. Derive eigenmode functions
2. Matching on the discontinuous plane
Analysis method
PEC/PMC
[1] D Kim, et al., IEEE Trans. Microw. Theory Techn., vol. 64,
no. 3, pp. 776-784, Mar. 2016. [2] T. Tomura, et al., IEEE Access,
vol. 7, pp. 164080--164088, Nov. 2019.
https://ieeexplore.ieee.org/document/7390112https://ieeexplore.ieee.org/document/8896011
スライド番号 1
