A Wideband and Low-Loss Spatial Power Combining Module for mm-Wave High-Power Amplifiers
Journal article, 2020

We present a low-loss power combiner, providing a highly integrated interface from an array of mm-wave power amplifiers (PAs) to a single standard rectangular waveguide (WG). The PAs are connected to an array of parallel and strongly coupled microstrip lines that excite a substrate integrated waveguide (SIW) based cavity. The spatially distributed modes then couple from the cavity to the rectangular WG mode through an etched aperture and two stepped ridges embedded in the WG flange. A new co-design procedure for the PA-integrated power combining module is presented that targets optimal system-level performance: output power, efficiency, linearity. A commercial SiGe quad-channel configurable transmitter and a standard gain horn antenna were interfaced to both ends of this module to experimentally demonstrate the proposed power combining concept. Since the combiner input ports are non-isolated, we have investigated the effects of mutual coupling on the transmitter performance by using a realistic PA model. This study has shown acceptable relative phase and amplitude differences between the PAs, . within +/- 15 degrees and +/- 1 dB. The increase of generated output power with respect to a single PA at the 1-dB compression point remains virtually constant (5.5 dB) over a 42% bandwidth. The performed statistical active load variation indicates that the interaction between the PAs through the combiner has negligible effect on the overall linearity. Furthermore, the antenna pattern measured with this combiner shows negligible deformation due to non-identical PAs. This represents experimental prove-of-concept of the proposed spatial power combining module, which can be suitable for applications in MIMO array transmitters with potentially coupled array channels.

integration

array amplifiers

Linearity

Antenna feed

mode converter

System-on-chip

spatial power combining

Geometry

MMIC

Power generation

Transmitters

Apertures

Author

Artem Roev

Chalmers, Electrical Engineering, Communication and Antenna Systems, Antennas

Eindhoven University of Technology

Parastoo Taghikhani

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics, Microwave Electronics

Rob Maaskant

Eindhoven University of Technology

Chalmers, Electrical Engineering, Communication and Antenna Systems

Christian Fager

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Marianna Ivashina

Chalmers, Electrical Engineering, Communication and Antenna Systems, Antennas

IEEE Access

2169-3536 (ISSN)

Vol. 8 194858-194867

Subject Categories

Telecommunications

Electrical Engineering, Electronic Engineering, Information Engineering

Signal Processing

DOI

10.1109/ACCESS.2020.3033623

More information

Latest update

2/18/2021