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Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor
Published on: August 30, 2012
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Concept of Planar Waveguide-Based m × n Terahertz Power Combiner
Rihab Hamad1, Israa Mohammad1, Thomas Haddad1
1Optoelectronics Department, University of Duisburg-Essen, 47057 Duisburg, Germany.
Sensors (Basel, Switzerland)
|March 28, 2026
Summary
This study introduces a novel 2D waveguide power combiner for scalable terahertz (THz) applications. The innovative design achieves high power combining efficiency, enabling advanced THz photodiode arrays.
Area of Science:
- Electrical Engineering
- Optoelectronics
- Microwave Engineering
Background:
- Conventional power combiners are typically 1D, limiting scalability for multi-port terahertz (THz) systems.
- Integrating multiple modified uni-traveling carrier (MUTC) THz waveguide photodiodes (PDs) requires efficient power combination in a 2D array.
Purpose of the Study:
- To present the first planar (2D) waveguide-based power combiner (PC) architecture.
- To demonstrate scalability for increased input ports and operating frequency bands.
- To develop an integrated photodiode for efficient THz power coupling into the waveguide.
Main Methods:
- Utilized H-plane rectangular waveguide T-junctions and polarization twisters for a 2D power combiner design.
- Performed full-wave numerical analysis for 2x2 and 2x4 power combiner configurations in the WR3 band (220-320 GHz).
- Designed and simulated a novel slot-bow tie antenna integrated MUTC photodiode for vertical THz power radiation.
Main Results:
- The 2x2 power combiner achieved a return loss of 11 dB and ~90% power combining efficiency.
- The 2x4 power combiner demonstrated a return loss >10 dB and ~85% efficiency.
- The integrated photodiode exhibited reflection loss <10 dB and insertion loss <1.4 dB across the WR3 band.
Conclusions:
- The proposed 2D power combiner offers a scalable solution for coherent power combination in THz systems.
- The integrated photodiode design facilitates efficient coupling of optically generated THz power into the waveguide.
- This work enables the development of advanced 2D THz photodiode arrays for various applications.
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