01 / Data Control
Packet & signaling path
Reliable framed data with CRC-8, ACK/NAK, retries, duplicate protection, source and destination addresses.
InfraRed optical communications
Talk through
light.
Our communicators exchange data and voice through a directional beam of invisible infrared light.
- Uses no Wi-Fi, Bluetooth, cellular network, or conventional radio transmission.
- Directional, line-of-sight operation limits signal exposure outside the intended optical path.
- Less susceptible to conventional radio-frequency interference and RF jamming.
- Supports digital data, control signaling, and voice through dedicated infrared channels.
- Can extend coverage through optical repeaters and bridge longer distances using a fiber-optic backbone.
Core architecture
One system.
Two optical paths.
The project keeps data and continuous speech transmissions separate. Proven 38 kHz modules handle addressed messages, acknowledgements, calls and PTT states. A dedicated broadband optical system preserves the analog information needed for intelligible voice.
02 / Voice Control
Continuous voice path
The headset microphone feeds an analog preamp and dedicated voice emitter. A broadband receiver recovers speech for a low-power headphone amplifier.
Hardware & components
The foundation hardware.
The packet link starts with an Arduino Nano, a 38 kHz receiver and a 38 kHz transmitter in each handheld. The pin assignments below preserve room for controls, headset audio, status indicators and future fiber.
Controller
Arduino Nano V3.0
The ATmega328P Nano runs packet framing, CRC checking, acknowledgements, OLED status and later call-control logic. Its compact 5 V platform is the project’s handheld controller.
Packet input
HX-M121 IR Receiver
Receives demodulated 38 kHz burst-coded packet and control signals. It is used for text, ACK/NAK, addressing, call state and PTT events—not continuous speech.
Packet output
HX-53 IR Transmitter
Sends the 38 kHz packet and control channel from the Nano. It carries structured data and signaling; the later continuous-voice path uses a separate higher-power emitter and driver.
Governing connection map
Master Nano pin assignment
Current connections are already used by the packet/OLED baseline. Planned and reserved pins must remain available until their roadmap stage is reached.
D0/D1USB Serial RX / TXRESERVED
D238 kHz packet IR RXCURRENT
D338 kHz packet IR TXCURRENT
D4PTT buttonSTAGE 16
D5-D7Menu Up / Down / SelectPLANNED
D8Green status LEDPLANNED
D9Audio PWM / controlled test sourceTIMER CHECK
D10Yellow status LEDPLANNED
D11/D12Future fiber TX / RXSTAGE 28
D13Onboard diagnostic LEDCURRENT
A0Conditioned CTIA microphone inputSTAGE 17
A1Battery monitorPLANNED
A2Volume or gain controlPLANNED
A3Red status LEDPLANNED
A4/A5OLED SDA / SCLCURRENT
A6/A7Spare analog inputsRESERVED
Current baselinePlanned functionReserved / future
Master development roadmap
28 measured steps.
Filter the program by phase. Foundations establish the dependable text link. Voice stages develop the headset audio and free-space optical channel. Network stages add selection, repeating and fiber.
System expansion
From handheld link to optical network.
The architecture evolves without discarding the reliable subsystems already proven. Arduino Nano boards supervise the operator interface and signaling while dedicated analog electronics handle speech.
Handheld platform
Arduino Nano communicator
D2 / D338 kHz packet RX / TX
D4-D7PTT, Up, Down and Select controls
D8/D10/A3Green, yellow and red status LEDs
A0Conditioned headset microphone input
A4 / A5SSD1306 OLED over I2C
Expansion architecture
Repeater and fiber network
Stage 26Loop-safe packet/control repeating
Stage 27Fiber backbone between IR sectors
Stage 28Direct handheld packet-data fiber port
D11 / D12Reserved fiber TX / RX pins
FutureHybrid routing and fiber voice research
Project documents
The engineering record.
The full master roadmaps contain objectives, starting baselines, planned additions, operator examples, verification requirements and success criteria for every stage.
Foundation volume
Stages 1–14
From a single received byte through reliable, OLED-equipped, symmetrical two-way text communication.
Expansion volume
Stages 15–28
Addressing, PTT, private headset voice, optical audio, multi-unit operation, repeaters and fiber.
Build in verified increments
Every stage introduces one major concept, passes a defined success test, and becomes the known-good baseline for the next.
Private, speakerless audio
A 3.5 mm CTIA TRRS headset supplies both microphone and earbuds. The handheld has no onboard microphone or loudspeaker.
Stay Nano-conscious
Fixed-size buffers, U8x8 OLED text mode and deliberate pin/timer planning respect the ATmega328P’s limited resources.
Important notices
Security and safe operation.
The IR Optical Communicator is an experimental prototype. These notices describe important limitations and precautions for anyone building, testing or using the system.
Notice 01 / Security
Experimental Security Notice
Directional infrared communication can reduce unintended signal exposure, but it should not be considered interception-proof or unjammable. Infrared signals may be detected, recorded, reproduced, blocked, or overwhelmed by specialized equipment. This prototype is not intended for emergency, military, medical, or other mission-critical communications.
Notice 02 / Safety
Infrared Safety Notice
Infrared light may be invisible to the human eye. High-power infrared emitters can still present an eye-safety hazard even when no visible light is apparent. Use current-limited emitters, suitable diffusers or optics, appropriate operating distances, and applicable photobiological safety guidance. Never look directly into an energized emitter or aim it toward another person’s eyes.