Modular Plane Wave Synthesis Units for Large RF Testing

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Solution Overview

Problem

Existing RF equipment testing systems, such as those for cellular network base stations, require large and complex compact antenna test ranges (CATR) due to the size of the equipment, necessitating a more compact and efficient testing solution.

Innovation Solution

A plane wave synthesis system comprising multiple pre-calibrated plane wave synthesizer units arranged to generate a combined quiet zone, utilizing signal distribution networks and optimization algorithms to create a large enough quiet zone for testing, allowing for efficient and cost-effective testing of large RF equipment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If a single large plane wave synthesizer is used to test large RF equipment, then the quiet zone size is sufficient, but the device complexity and cost increase significantly

Engineering Contradiction:
Improvequiet zone sizeVSAvoidsystem complexity
Core Design Contradiction:
Area of stationary objectVSDevice complexity

Solution Approach 1:

The patent divides a large plane wave synthesizer into multiple smaller synthesizer units (e.g., 2x2, 3x3, or 4x4 configurations). Each unit contains a subset of antenna elements that can be independently controlled. These segmented units are arranged in a grid pattern to collectively form the complete quiet zone, reducing the complexity of any single unit while maintaining the required overall quiet zone size.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Multiple smaller plane wave synthesizer units are combined to function as a single large synthesizer. The units are synchronized through a master clock signal and controlled by a central controller that coordinates their operation. This merging approach allows the system to achieve the quiet zone size of a large synthesizer while using simpler, modular units that are easier to manufacture, transport, and maintain.

Inventive Principle:
Principle #5Merging (Combining)

2Area of stationary object

If a single large plane wave synthesizer is used, then the quiet zone size is sufficient, but the system becomes difficult to transport and deploy

Engineering Contradiction:
Improvequiet zone sizeVSAvoidtransportability
Core Design Contradiction:
Area of stationary objectVSEase of operation

Solution Approach 1:

The large synthesizer is segmented into multiple smaller units that can be individually transported using standard equipment. Each unit has reduced mass and dimensions, making them suitable for transport by conventional means rather than requiring specialized heavy equipment. The modular design allows units to be moved, assembled, and deployed at different test locations.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The smaller synthesizer units are designed to be stackable or nestable when not in use, optimizing their transport footprint. The antenna elements and support structures are configured to fit within each other or align in compact arrangements during transportation, maximizing space utilization and reducing the overall transport volume required.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Ease of operation

If multiple synthesizer units are used, then the system becomes more modular and transportable, but the coordination and calibration complexity increases

Engineering Contradiction:
ImprovemodularityVSAvoidcoordination complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

A feedback mechanism is implemented where each synthesizer unit reports its operational status, phase alignment, and calibration data to a central controller. The controller processes this feedback and adjusts the control signals to each unit to maintain synchronized operation. This closed-loop control system automatically compensates for minor variations in unit performance, reducing the manual coordination effort required.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The synthesizer units are pre-calibrated during manufacturing with reference to a master unit or reference standard. This preliminary calibration establishes baseline phase and amplitude relationships that simplify field deployment. The pre-configured units require minimal adjustment when assembled, as the majority of the coordination complexity has already been resolved during the calibration phase.

Inventive Principle:
Principle #10Preliminary action

4Reliability

If traditional CATR systems are used for large RF equipment, then the testing capability is sufficient, but the system size and cost become prohibitive

Engineering Contradiction:
Improvetesting capabilityVSAvoidsystem volume
Core Design Contradiction:
ReliabilityVSVolume of stationary object

Solution Approach 1:

The traditional monolithic CATR system is segmented into multiple smaller synthesizer units arranged in a grid. Each unit contributes a portion of the overall quiet zone through coherent signal combination. This segmentation allows the system to achieve the same effective testing volume and capability as a traditional large CATR while using a more compact modular architecture that reduces the overall physical footprint and associated infrastructure requirements.

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system enables the generation of a large quiet zone for testing RF equipment, providing a compact, easy-to-transport, and cost-effective solution that maintains testing quality, accommodating devices like cellular network base stations.

Implementation Method 1

a respective plurality of antenna elements 102-11 - 102-1n, 102-21 - 102-2n that are arranged in a plane of main extension of the respective plane wave synthesizer unit 101-1, 101-2

Methodology Applied
Scientific EffectElectromagnetic radiation: Electromagnetic Induction

Data Source

PatentEP4607210A1Plane wave synthesis system, method for synthesizing a plane wave, and method for testing RF equipment
Publication Date: 2025.08.27 ROHDE & SCHWARZ GMBH & CO KG
  • EP4607210A1 patent drawingFigure 1
  • EP4607210A1 patent drawingFigure 2
  • EP4607210A1 patent drawingFigure 3

AI summary

The present disclosure provides a plane wave synthesis system comprising at least two plane wave synthesizer units, each one of the plane wave synthesizer units comprising a plurality of antenna elements that are arranged in a plane of main extension of the respective plane wave synthesizer unit and that are coupled to a signal input of the respective plane wave synthesizer unit, wherein the at least two plane wave synthesizer units are configured based on the relative positions between the at least two plane wave synthesizer units to generate a plane wave in a combined quiet zone. Further, the present disclosure provides a method for synthesizing a plane wave, and a method for testing RF equipment.