CONSUMER ELECTRONICS

Long-Range Bluetooth Audio Transmitter & Receiver

Project Overview

Designed a dual-mode Bluetooth audio transmitter and receiver system capable of transmitting real-time natural sounds up to 1 km. The solution allows users to experience ambient nature audio indoors via an outdoor mic-equipped transmitter disguised as a nut.

HARDWARE | FIRMWARE | MOBILE/WEB APPS

Client Requirement & Objectives

Seamless Indoor Nature Audio Experience

The system should enable real-time transmission of outdoor audio, particularly useful during harsh winters or in noise-controlled environments, allowing users to experience nature sounds indoors.

Nature-Inspired Aesthetic

The transmitter casing was required to mimic the shape and texture of a natural nut, making it discreet for placement in bird nests or on tree branches

Dual-Mode Hardware Design

A single hardware design should support both transmitter and receiver functionalities, made possible through configurable firmware or settings.

Integrated Components in Compact Form

The transmitter needed to house a sensitive microphone, a long-range Bluetooth module (up to 1 km), and a 3000mAh rechargeable battery, all within the small nut-shaped enclosure.

System Design & Build

Dual-Mode Hardware

Designed a single PCB that could be configured via firmware as either a transmitter or receiver to simplify production.

Long-Range Bluetooth Design

Integrated a high-gain Bluetooth module capable of transmitting audio up to 1 km with low latency.

Custom Nut-Shaped Enclosure

Engineered the internal layout to fit within the organic nut shape, maintaining aesthetics and functionality.

Audio Path Optimization

Tuned the microphone and audio signal path to deliver clear, natural sound with minimal distortion even in variable weather conditions.

Key Challenges & Solutions

PPCB & Mechanical Constraints

Fitting a full-featured PCB, microphone, and 3000mAh battery inside a small, irregular nut shape required custom 3D board design and strategic component placement.

Microphone Positioning

Ensured optimal mic placement on the shell exterior to capture clean audio regardless of device orientation in trees or nests.

Power Management

Implemented a power-saving protocol that activates Bluetooth audio transmission only when a receiver is actively connected, falling back to BLE advertising in standby.