A Substrate-Integrated Waveguide Filtering Power Divider with Broadside-Coupled Inner-Meander-Slot Complementary...

Area of Science:

• Microwave Engineering
• Electromagnetics
• Integrated Circuits

Background:

• Substrate-integrated waveguide (SIW) technology offers a low-cost, high-performance platform for microwave circuits.
• Filtering power dividers are crucial components for signal processing and system integration.
• Conventional designs often face challenges in achieving size reduction without compromising performance.

Purpose of the Study:

• To develop a compact SIW filtering power divider.
• To enhance the performance of complementary split-ring resonators (CSRRs) for size reduction.
• To integrate filtering and power division functionalities into a single, miniaturized unit.

Main Methods:

• Integration of meander-shaped slots into CSRRs to create an inner-meander-slot CSRR (IMSCSRR).
• Enhancement of equivalent capacitance and inductance in the IMSCSRR for frequency lowering and size reduction.
• Broadside-coupling of two IMSCSRRs within the SIW structure for further miniaturization.

Main Results:

• A two-way filtering power divider was implemented with a center frequency of 3.53 GHz and a 320 MHz bandwidth.
• Achieved in-band insertion loss of (3 + 1.3) dB and isolation over 21 dB.
• Demonstrated a size reduction of approximately 30% compared to non-broadside-coupled designs, with good magnitude and phase characteristics.

Conclusions:

• The proposed SIW-IMSCSRR filtering power divider effectively balances low loss, high isolation, and compact size.
• The design is suitable for integration into microwave systems requiring miniaturization.
• The modified CSRR approach offers a viable solution for reducing the physical footprint of SIW circuits.