Wireless connectivity has become an integral part of our daily lives. As we enter 2024, the two major wireless technologies LiFi and WiFi continue to evolve with new capabilities and applications. But which one is better for different use cases? This comprehensive guide examines the latest updates in LiFi and WiFi technology, compares their speed, reliability, security, coverage range, costs, and more to help you decide.
How LiFi Works
LiFi, or Light Fidelity, provides wireless communication through visible light and LED bulbs. The technology modulates the light from LED bulbs to transmit binary data which is then received by photo detectors.
LiFi uses visible light between 400 and 800 THz frequencies. This provides nearly 1000 times more bandwidth compared to WiFi which uses radio frequencies. This allows LiFi theoretically reach speeds up to 224 Gbps.
The major components of a LiFi system include:
- LED transmitter: LED bulbs that modulate light to transmit data.
- Photo detector: Receiver with a photodiode to detect light signals.
- Microcontroller: Encodes and decodes binary data.
How WiFi Works
WiFi uses radio frequencies between the range of 2.4GHz to 5GHz for wireless communication. These radio signals are transmitted using WiFi routers and received by devices with WiFi connectivity.
Early WiFi standards provided speeds up to 54 Mbps. But the latest WiFi 6 standard offers theoretical download speeds up to 9.6 Gbps, with typical speeds around 500 Mbps for today’s internet plans.
Speed Comparison
| Parameter | LiFi Speed | WiFi Speed |
|---|---|---|
| Maximum Theoretical Speed | 224 Gbps | 9.6 Gbps WiFi 6 |
| Typical Peak Speed | 100 Mbps | 500 Mbps |
While LiFi offers higher maximum speeds, typical peak speeds on today’s LiFi networks reach about 100 Mbps. On the other hand, WiFi 6 can deliver typical speeds up to 500 Mbps, with 9.6 Gbps theoretical maximum.
Reliability and Stability
Since LiFi uses visible light, it offers reliable connections even in areas with a lot of electromagnetic disturbances from other sources. This makes it suitable for environments like hospitals and aircraft cabins. WiFi relies on radio waves which are more prone to interference from other devices. But modern router designs are highly efficient at filtering noise and stabilizing connections. Upcoming WiFi 6E routers can use new 6 GHz frequency band for even more reliability. So while LiFi wins theoretically, WiFi connections can match or exceed LiFi on reliability.
Coverage Range
The reliable coverage range for LiFi is typically a 10 meter circle around each LiFi transmitter. Special IR enhanced variants claim increased range up to 50 meters. In comparison, WiFi routers can provide stable coverage for 50 to 100 meters indoors, and 300 meters outdoors with directional antennas. So in terms of range, WiFi easily beats LiFi technology. Long range LiFi connectivity continues to remain a challenge.
Mobility and Line of Sight
Since LiFi relies on light beams, it can only work with direct line-of-sight access to light sources. This impacts seamless mobility across rooms or spaces using LiFi. Work is ongoing to allow smooth handover between LiFi access points.
But WiFi radio waves can penetrate through walls, metal, and other obstacles much better. This enables excellent mobility and roaming across homes and buildings with WiFi networks. It does not require receiver devices to be in the line-of-sight of routers. So WiFi wins in terms mobility.
Energy Efficiency
LiFi has the edge over WiFi when it comes to energy efficiency. Since LiFi technology reuses LED bulbs for data transmission, it consumes very little additional energy compared to lighting requirements.
WiFi needs dedicated radio transmitters that consume 2 to 10 watts on average per data transmission node. So if you’re looking for low power wireless communication at home or offices, LiFi has the advantage.
Security
LiFi can provide certain security benefits since visible light signals get fully confined within closed spaces. External data sniffing and leakage risks are lower. But researchers have shown internal reflection based exploits to crack LiFi signals.
WiFi standards incorporate advanced encryption protocols like WPA3 to enhance data protection and user privacy. So, while both technologies offer some pros and cons around security, WiFi likely provides stronger overall protection with well implemented encryption.
Deployment Costs
LiFi hardware including the required LED transmitters cost about $70 per node as per latest estimates. Retrofitting existing infrastructure drives costs higher.
WiFi routers and access points now cost less than $50 even for high end models. And most homes and offices already have WiFi networks deployed, so incremental costs are very low. From cost perspective, WiFi clearly provides better overall value. LiFi deployment costs need to reduce further with large scale production.
Use Case Differences
Despite the rapid growth of WiFi technology, LiFi offers unique benefits in certain use cases:
- Hospital environments with medical devices sensitive to RF interference.
- Aircraft passenger internet access without radio interference risks.
- Underwater data transmission leveraging new ultraviolet LiFi variants.
- High density locations like stadiums and event venues.
For widespread general purpose use at homes and offices, WiFi remains the norm due to mobility, cost and availability factors.
| Feature | LiFi | WiFi |
|---|---|---|
| Technology | Uses light waves to transmit data | Uses radio waves to transmit data |
| Medium of Transmission | Visible light spectrum (LEDs) | Radio frequency spectrum (2.4 GHz or 5 GHz) |
| Speed | Extremely high (up to several Gbps) | High (varies, typically up to several hundred Mbps) |
| Range | Limited (few meters to a room) | Wider range (tens to hundreds of meters) |
| Interference | Immune to electromagnetic interference | Susceptible to interference from other devices and signals |
| Security | High security due to localized transmission | Security measures required (WPA2, WPA3, etc.) |
| Connection Density | Limited by the number of light sources | Can handle a larger number of connected devices |
| Deployment | Suitable for environments with controlled lighting conditions | Widely deployed in various environments |
| Line of Sight | Requires line of sight between transmitter and receiver | Works through obstacles, but can be affected by them |
| Energy Consumption | Generally lower energy consumption | Can be energy intensive, depending on usage |
| Health Concerns | No known health concerns related to visible light communication | Some concerns about long-term exposure to radio waves |
| Implementation Cost | Initially higher due to specialized equipment | Lower initial cost due to widespread availability of devices |
| Data Density | Limited by the number of light sources | Can handle high data density in crowded areas |
| Versatility | Limited in mobility due to line of sight requirement | Offers greater mobility and flexibility |
| Compatibility | Requires LiFi enabled devices (specialized hardware) | Compatible with a wide range of devices |
| Standards | Still evolving with standards like IEEE 802.15.7 | Standardized under IEEE 802.11 |
Conclusion
As the comparison shows, both LiFi and WiFi have their relative merits and limitations. WiFi easily beats LiFi in parameters like typical speed, mobility, range and costs. But LiFi offers advantages for some niche applications like RF sensitive environments, energy efficiency and dense deployments. While ongoing enhancements can help LiFi catch up with WiFi capabilities, it seems unlikely for full convergence in the foreseeable future. With investments exceeding $1 trillion, WiFi remains firmly entrenched as the wireless connectivity standard for the next decade at least.
LiFi adoption is growing steadily across industries. But it faces barriers like higher hardware costs, device compatibility issues and lack of seamless mobility that WiFi has finely honed over decades of innovation. As vendors figure out integration and mobility for LiFi technology across devices, its growth can accelerate. Till then, WiFi 6 seems poised as the leading wireless standard with LiFi addressing certain niche roles.
FAQs
Does LiFi work with my phone?
Currently, smartphone LiFi support is limited. Few Android models have demo capabilities but not full integration. iPhones do not yet support LiFi. New devices in 2024 are expected to incorporate LiFi along with WiFi.
Is LiFi safe for eyes?
Yes, LiFi uses only normal visible light for communication that is well within safe exposure limits. There are no harmful UV rays or laser beams involved.
Can LiFi fully replace WiFi?
While early LiFi adoption is growing for specific use cases, it cannot fully replace WiFi yet in the foreseeable future. WiFi offers key benefits like mobility, widespread device support and lower costs that LiFi has not matched.
What are LiFi hotspots?
LiFi hotspots are similar to WiFi routers but use LED light transmitters instead of radio antennas. They create a connectivity bubble of around 10 meter diameter without radio interference.
Does weather impact LiFi signals?
LiFi relies on direct line-of-sight access between LED fixtures and photo detectors. So fog or thick snow can potentially block some signals when outdoors. Indoor transmission generally works reliably in any weather.
