# How Air Conditioners Use Radio Signals to Locate Your Remote Control

> A system that helps an air conditioner remote find its own location inside a building by comparing radio signal strengths from multiple AC units against its last known position.

- **Patent:** US 12398901
- **Original title:** Air conditioning system, operation terminal, and non-transitory computer-readable storage medium
- **Owner:** Mitsubishi Electric Corp
- **Granted:** 2025
- **Status:** Active
- **Times cited:** 0
- **Field:** consumer_electronics, ai_ml, mechanical

## What it does

This system uses a network of air conditioners that constantly broadcast beacon signals. The user's remote control picks up these signals and measures their radio wave intensity. Instead of just guessing where it is, the remote calculates its current position by looking at its previous known location and comparing the current signal strengths to a set of pre-mapped candidate locations in the room. It specifically looks for the best match by comparing the order of signal strengths to the expected distances from each AC unit, using a mathematical method called Levenshtein distance to find the most likely spot.

## What it does NOT cover

- Does not cover systems that rely solely on GPS for indoor positioning
- Does not cover location tracking that ignores the device's previous known position
- Does not cover systems that use visual markers or cameras to determine location
- Does not cover non-radio based proximity detection like ultrasound or infrared

## The clever bit

It treats the signal strength order as a sequence and uses Levenshtein distance—a technique usually meant for comparing text strings—to match the observed signal pattern to a physical location.

## Real-world examples

1. Commercial office building climate control systems
2. Hospital HVAC management interfaces
3. Smart building facility management apps

## Why it matters

In large commercial buildings like offices or hospitals, managing individual climate zones is difficult. This technology allows a mobile controller to automatically adjust the settings for the specific unit closest to the user without manual input. It streamlines building automation by ensuring the control interface always reflects the user's immediate physical environment.

## Frequently asked questions

### What does How Air Conditioners Use Radio Signals to Locate Your Remote Control cover?

A system that helps an air conditioner remote find its own location inside a building by comparing radio signal strengths from multiple AC units against its last known position.

### Who owns patent US 12398901?

Mitsubishi Electric Corp owns this patent, granted in 2025.

### When does this patent expire?

This patent is expected to expire on August 26, 2045, when the invention enters the public domain.

### What problem does this patent solve?

In large commercial buildings like offices or hospitals, managing individual climate zones is difficult. This technology allows a mobile controller to automatically adjust the settings for the specific unit closest to the user without manual input. It streamlines building automation by ensuring the control interface always reflects the user's immediate physical environment.

### What does this patent NOT cover?

Does not cover systems that rely solely on GPS for indoor positioning

**Full plain-English explainer:** https://patentbrief.org/patent/us/12398901/raptor-thrust-to-weight

**Original patent:** https://patents.google.com/patent/US12398901

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._