Summary of "【教えて毛利さん】トゲトゲ8,000個！？謎の部屋の秘密！"

Overview

A newly built anechoic (radio‑wave absorber) room in Makuhari is used to measure antenna and radio performance in a reflection‑free environment. Measurements taken inside this chamber emulate outdoor, free‑space conditions and are used to inform and improve product design and integration.

Anechoic chamber (Makuhari facility)

Purpose: provide a reflection‑free space for accurate antenna and radio measurements.
Environment: walls lined with radio‑wave absorbers so the room does not act like a metal reflector.

Radio‑wave absorbers

Physical form: soft, spiky foam panels (pyramidal “spikes”).
Function: absorb unwanted radio waves to prevent reflections and simulate free‑space conditions.

Measurement system

Main components: a measurement setup called CATER plus a reflector bridge.
Reflector bridge: “bends” or folds radio waves so long‑range tests can be performed in a much smaller chamber.

Practical benefit: measurements that would normally require a >30 m anechoic chamber can be performed in roughly a 7 m room.

Antenna testing hardware and procedure

Satellite antenna: installed in the chamber for testing (previously shown on TechDe).
Rotator: a motorized mechanism that rotates the antenna to measure directionality and radiation patterns.
Procedure:
- Move/rotate devices in small increments.
- Measure control/beam characteristics at each increment to determine the directions in which radio waves propagate.

Data capture and use

Measurement results are displayed on a PC.
Tx (transmission) and Rx (reception) performance measured in the chamber are used to refine product design and system integration.