So your fancy new headphones came in a lovely Bluetooth edition, but your old TV remote still uses something called infrared to change channels. What gives? As a tech geek and self-proclaimed wireless historian, let me decode the practical past, present and future differences between these fundamental wireless technologies – Bluetooth and infrared.
Both enable devices to communicate without cables, but the techniques used under the hood have crucial impacts on performance, use cases, and popularity over time. Bluetooth clearly dominates most modern wireless gadgets, while infrared remote controls stubbornly hang on. This guide will unpack the key distinctions in plain language to resolve the wireless alphabet soup.
A Brief History of Two Very Different Wireless Methods
First, a quick crash course history on how we arrived at this crossroads between light waves and radio waves for gadget communication…
Infrared Data Transmission: Older Than You Think
Engineers started tinkering with wireless infrared technology back in the 1950s to create early television remote controls. The introduced the clunky wired remotes that literally clicked tuning dial components inside older TVs sets.
Infrared offered freedom to control TVs from across the room without strings attached. Through the 1980s and 90s, infrared connections extended inside computers between components like printers and keyboards.
An industry group called IrDA (Infrared Data Association) formed in 1993 to standardize infrared protocols enabling compatibility between the piles of infrared modems, keyboards, printers and Palm Pilots suddenly flooding the market.
Bluetooth: Designed to Cut the Cord Completely
Flash forward to 1994 when Ericsson engineers hatched a project aimed squarely at replacing the RS-232 serial cables used at the time to transfer data between devices. Code named after a 10th century viking king famous for unification, Bluetooth promised wire-free links that would bring fragmented device ecosystems together.
The non-profit Bluetooth Special Interest Group (SIG) soon formed to guide advancement of this radio-based wireless standard. Early focus centered on variations used primarily with mobile phone headsets and handsfree systems. But Bluetooth ultimately expanded far beyond to practically any gadgets imaginable, from speakers to smartwatches to appliances.
So in summary – infrared pioneered initial wireless godsends like click-free channel surfing, while Bluetooth delivered the promise (mostly) of completely cordless connectivity between our modern menagerie of computers, phones, peripherals and smart gadgets.
Light vs Radio Waves: How These Technologies Actually Work
The key difference between Bluetooth and infrared lies in the wireless medium used to transmit data. Think of it like AM/FM radio stations vs visible light waves.
Infrared: Line-of-Sight Light Communication
Infrared technology relies on light waves just beyond the visible light color spectrum detectable by the human eye. Specifically, infrared devices communicate by continuously turning an LED light emitter on and off very rapidly. This generates pulses of invisible infrared light aimed at a photodiode receiver which translates light fluctuations into electrical signals representing data.
So in a TV remote for example, the onboard computer and button inputs modulate or encode a specific infrared LED light signature. The infrared sensor on the TV sees this pulsing light pattern and decodes it to understand, "Oh, the channel up button was pressed! I should move to the next channel…"
Remote controls generally operate using light around 940 nanometers, while higher performance connections may employ wavelengths ranging from 300 GHz to 400 GHz. (For comparison, Wi-Fi resides down at 2.4 GHz or 5 GHz frequencies).
Key Advantages:
- Very inexpensive components like basic LEDs and photodiodes
- Uses harmless invisible light rather than radiation
Key Disadvantages:
- Requires clear line-of-sight between devices
- Short range – only around 10 meters typically
- Sensitive to alignment and positioning between devices
- No native security features
Bluetooth: Omnidirectional Radio Wave Networks
Bluetooth also shuttles data wirelessly between devices, but leverages omnidirectional 2.4 GHz radio waves instead (the same spectrum where your Wi-Fi hangs out). Bluetooth devices have built-in transceivers with antennas that both transmit and receive these radio signals.
Internally, Bluetooth uses fast frequency hopping, swapping through different frequencies up to 1600 times per second. This allows multiple devices to communicate simultaneously without interfering using 79 different bands.
Sophisticated antenna designs also enable largely omnidirectional transfer, where devices connect reliably regardless of orientation or line-of-sight compared to infrared.
Bluetooth connections share bandwidth efficiently in a piconet structure that supports up to 8 actively communicating devices. Multiple independent piconets can then be linked into larger networks called scatternets.
Key Advantages:
- No line-of-sight required
- Robust penetrate through walls and obstructions
- Beam forming focuses signals directly between devices
- Networks with 7 active peripheral connections
- Encryption and authentication built-in
Key Disadvantages
- Components like radio chips cost more
- Slight interference possibilities with congested Wi-Fi
- Licensing and regulatory complexity
Now that we understand these technologies differ significantly in terms of physics, let‘s explore the implications in day to day use…
Why Bluetooth Trounced Infrared in Most Modern Gadgets
Given its reliance on light waves, infrared connections inherently suffer limitations that Bluetooth radio solutions easily overcome. These advantages help explain Bluetooth‘s domination across everything from wireless speakers to smart home devices:
1. Bluetooth Allows Robust Multi-Device Networks
A key advantage is Bluetooth‘s native ability to juggle simultaneous connections with up to 7 other active peripheral devices like wireless keyboards, headphones and controllers. Ever try using multiple infrared keyboards and mice with one computer? Headaches galore. Bluetooth‘s flexible "piconet" structure makes linking devices plug-and-play simple.
Infrared can physically allow sequential multi-device connections, but lacks native orchestration capabilities equivalent to Bluetooth profiles and protocols. Real-world complexity makes large infrared networks extremely impractical.
2. Bluetooth Blankets Entire Rooms Reliably
Bluetooth‘s improved range approaching 100 meters combined with radio wave penetration through walls and human bodies enables robust coverage across typical rooms filled with roving users and portable devices.
Infrared requires gadgets to visually align within several meters continuously. Can‘t have a dancing receiver miss more than a few beat‘s worth of blinks from that TV remote! This makes Bluetooth far easier for video gaming, presenting slides, or just binge watching Netflix from the couch or kitchen.
3. Bluetooth Technology Drains Far Less Power
Bluetooth uses very conservative control procedures allowing months or years of battery life from connected tags or sensors powered by coin cell batteries. Efficient duty cycling also means Bluetooth drains relatively little juice from mobile devices like headphones.
Emitting infrared waves efficiently guzzles considerably more power, rendering infrared less ideal for portable battery-based applications. Though modern infrared remotes last upwards of a year on small batteries through improved efficiency.
4. Bluetooth Penetrates Barriers That Block Infrared
Radio waves innately propagate through various materials like walls and clothing that blot out infrared light entirely. This allows remote Bluetooth gadgets to work reliably throughout typical homes and offices. Infrared basically needs open air for any hope of stability.
5. Built-In Encryption and Authentication
Bluetooth incorporates encryption protocols during device pairing and encrypts ongoing data exchanges to provide enhanced security. There are still possible attack vectors, but Bluetooth offers essential protections lacking with plaintext infrared connections.
Current Practical Applications: Where These Technologies Fit Today
Given Bluetooth‘s superior technical capabilities, it now features prominently across hearing aids, smart home hubs, fitness trackers, game controllers, keyboards, cars…you name it!
But infrared still occupies some specific niches:
Bluetooth Rocks Mainstream Short Range Wireless
- Audio – Headphones, earbuds, speakers, hearing aids
- Computer/Phone Accessories – Keyboards, mice, gamepads
- Wearables – Smart watches, fitness trackers
- Internet of Things – Sensors, appliances, lighting, home automation
- Data Transfer – Files, contacts, media sharing between devices
- Automotive – Hands-free calling, infotainment pairing
Infrared Still Serves A Few Key Roles
- TV / Streaming Box Remotes
- Specialized medical devices communicating externally without implants
- Spectroscopy equipment analyzing materials by infrared signatures
- Proximity or ambient light sensors on gadgets like robot vacuums
- Cheap wireless in extremely low cost electronic devices
So while fading slowly into obscurity for most computing purposes as Bluetooth takes over, infrared still provides real unique value driven by physics advantages in a handful of applications.
The Future: Bluetooth Ever Expanding, Infrared Slow Decline
Bluetooth will continue expanding into wider applications and use cases as standards add capabilities:
- Bluetooth 5 now delivers 2x speed along with 4x range outdoors or "long range" 800+ foot connectivity
- Bluetooth LE Audio promises a new high-fidelity wireless sound protocol coming soon
- Directions like payments, location services, asset tracking seem inevitable
However, infrared likely persists for specialized commercial and healthcare gear or high-efficiency/low-cost gadgets where every penny matters and Bluetooth licensing costs hit hard. But for most modern electronics, all signs point to Bluetooth!
So in summary – Bluetooth and infrared take vastly different technical approaches to transporting data sans wires with respective pros and cons. Bluetooth‘s versatility has largely overtaken old-school infrared apart from some exceptions grandfathered in due to specific physics advantages that may take generations to disappear from TV channel surfing rituals!
I hope this guide served as a friendly explainer to demystify the alphabet soup a bit. Hit me up with any other wireless history topics you might want broken down – it‘s kind of my geeky specialty!
