VLC vs Wifi | Difference between VLC and Wifi
This page compares VLC vs Wifi and describes difference between VLC and Wifi wireless technologies. It covers basics of VLC vs WiFi including their features in order to derive difference between VLC and Wifi.
Following are the features of VLC communication.
• VLC technology uses visible light part of the light spectrum.
• It uses wavelength range from 380 nm to 750 nm (i.e. frequency range from 430 THz to 790 THz) for communication.
• Data to be transmitted is modulated before transmission by modulating the light. PA (Power Amplifier) is not needed unlike RF communication.
• LEDs and lasers are used as transmitter or source. Photodiode detectors are used as receivers.
• Similarly LiFi >> is one of the many applications of VLC (Visible Light Communication).
Following are the features of WiFi technology.
• WiFi works on radio frequency of usually around 2.5GHz or 5GHz.
• WiFi follows various WLAN standards such as 802.11a, 11n, 11ac, 11ad, 11n as defined by IEEE in order to deliver different data rates and distance coverages.
• As shown WiFi AP (Access Point) or Router is connected with internet broadband cable or with cellular network. All the wifi compatible mobile phones, tablets or laptops are connected with AP (or router) to obtain internet.
• WiFi network operates in either of two modes viz. adhoc (i.e. BSS-Basic Service Set) and infrastructure (i.e. ESS-Extended Service Set).
• In BSS WLAN compliant stations (i.e. STAs) communicate directly. In ESS WLAN compliant STAs communicate with APs (Access Points) to access internet.
• WiFi supports different speeds and coverage ranges as per implemented standard in the devices (STAs, APs). 802.11a supports upto 54 Mbps, 11b upto 11 Mbps, 11n supports 72 Mbps/150 Mbps as per BW (20MHz/40MHz), 802.11ac wave-1 supports upto 1.3 Gbps (80MHz, 3 streams, 256QAM), 802.11ac wave-2 supports upto 3.5 Gbps (160MHz, 4 streams, 256QAM) etc. The distance coverage of 70 meters (indoor) to 250 meters (outdoor) can be achieved.
|Full form||Visible Light Communication||Wireless Fidelity|
|Maturity of system||Less||More|
|Coverage Range||short (few meters)||Higher (tens of meters)|
|External Power||Do not require external power as it has power for LED lamp.||Need external power|
|Backhaul||Ethernet or powerline communication is used.||It is provided using ethernet or broadband connection.|
|RF and Antenna Front end||Do not required, moreover illumination power is used as transmit power.||Required, as wifi operates using EM waves.|
|Security||More secure as it confines the data transmission to one area.||Less secure as EM waves can not be confined to one particular region, Separate encryption techniques are to be employed in order to make wifi connection more robust.|
|Data density/Frequency re-use||Interference is bounded and hence reuse efficiency is higher.||WiFI prone to co-channel interference and hence more wifi nodes do not lead to increase in the data capacity linearly as it can be.|
|NLOS performance||communication can not be established in non line of sight if reflected signal is poor.||communication is possible but performance gets degraded if attenuation is more due to signal fading.|
|BOM (i.e. Bill of Materials)||Do not require expensive components such as RF devices and antenna. It is cheaper system.||RF and antenna are must for wifi to be exist. Hence it is costly compare to VLC.|