Advantages of 2.4 GHz WiFi | Disadvantages of 5 GHz WiFi
This page covers advantages and disadvantages of 2.4 GHz and 5 GHz WiFi versions. It mentions advantages of 2.4 GHz wifi, disadvantages of 2.4 GHz, advantages of 5 GHz wifi and disadvantages of 5 GHz.
Introduction: LAN (Local Area Network) refers to cabled version of network consisting of computing devices such as PCs, Laptops, Hubs, Switches with the help of ethernet cables. In certain situation it becomes difficult or impossible to lay ethernet cables. To avoid this problem, Wireless Local Area Networks (WLANs) have been developed which is popularly known as wifi. WLAN uses ISM frequency bands viz. 902-928, 2400-2483.5 and 5725-5850 MHz. WiFi follows IEEE 802.11 series of standards which works similar to traditional LAN except it has wireless interface. IEEE 802.11 defines PHY (layer-1) and MAC (layer-2) specifications to avail various QoS levels, Security, data rates and distances.
Figure-1 : Traditional LAN
Figure-2 : Wireless LAN
WLAN network can be implemeted in two ways i.e. adhoc mode and infrastructure mode. Adhoc mode is used by small number of mobile users and it does not require AP or router. Infrastructure mode is setup by APs (Access Points) or routers. Here group of stations belonging to an AP is called Basic Service Set (BSS). Multiple BSSs are connected to each other and to DS (Distributed System) by APs (Access Points). This is shown in the WLAN architecture above.
AP (Access Point) provides interoperability between wired computing devices and wifi devices. It is also known as wifi router. It is usually connected with single broadband internet connection so that multiple wifi devices can share single broadband connection eo experience very high speed browsing.
Both 2.4 GHz and 5 GHz frequencies are used in various wifi standards. Let us understand 2.4 GHz and 5 GHz radio frequencies used in these wifi versions. The figure depicts frequency spectrum of both 2.4 GHz and 5 GHz frequencies. As shown, 2.4 GHz will have less number of cycles in the same time period as 5 GHz. In Electromagnetic spectrum, 5 GHz is considered higher frequency than 2.4 GHz.
Figure-3 : 2.4 GHz vs 5 GHz waveforms
Following table mentions various features of IEEE 802.11 series of standards viz. 11b, 11a, 11g, 11n, 11ac and 11ax.
Table-1 : 802.11 WiFi Standards
2.4 GHz WiFi
Figure-4 : 2.4 GHz wifi channels
The figure depicts 2.4 GHz channels used in wifi network by routers or APs (Access Points) and Stations (STAs) or clients.
Among all the channels, channel-1, channel-6 and channel-11 are non-overlapping channels as they are
separated by spacing of 25MHz. Rest of these three channels are known as overlapping channels as
they share some frequency spectrum space.
Following are some of the silent features of 2.4 GHz WiFi.
• Better coverage range
• Universally compatible
• Used in 802.11b standard
• Lower bandwidth than 5 GHz version
• Higher interference due to use of 2.4 GHz by many devices. Moreover there are only three non-overlapping channels (i.e. 1, 6 and 11).
2.4 GHz wifi is used in large hotels which need coverage for guests in many rooms and outdoors. It is also used in pubs and restaurants which require cheaper wifi for customers and have multiple walls.
5 GHz WiFi
Figure-5 : 5 GHz wifi channels
The figure depicts 5 GHz channels used in wifi network.
As shown 25 pre-defined channels starting from 36, 40, 44, 48 and goes till 149, 153, 157, 161 and 165.
UNII-1 Channels are used for domestic applications and are best to use among 5GHz wifi channels.
These channels are used for various bandwidths (20 MHz, 40 MHz, 80 MHz, 160 MHz) in different WLAN standards.
Following are some of the silent features of 5 GHz WiFi.
• Faster network speed
• Less interference than 2.4 GHz
• More bandwidth options available
• Shorter range than 2.4 GHz version
5 GHz Wifi is used in cafes which attract working professionals and in hotels with meeting rooms and business events.
Benefits or advantages of 2.4 GHz WiFi
Following are the benefits or advantages of 2.4 GHz WiFi system:
➨It offers better coverage distances which is about 150 feet in indoor and 300 feet in outdoor.
➨The 2.4 RF signal can easily pass through walls, floors and solid objects.
➨It uses ISM frequency band which does not require to obtain licensing.
➨The 2.4 GHz wifi devices are less expensive.
Drawbacks or disadvantages of 2.4 GHz WiFi
Following are the drawbacks or disadvantages of 2.4 GHz WiFi system:
➨It supports less speed which is on the order of about 450 Mbps to 600 Mbps.
➨It supports lower bandwidth.
➨There are many wireless devices which uses 2.4 GHz frequency. Moreover there are only three non-overlapping channels compare to 23 channels used by 5 GHz wifi. Hence 2.4 GHz suffers from more interference than 5 GHz.
➨It supports less number of channels than 5 GHz WiFi.
➨It is liable to congestion.
Benefits or advantages of 5 GHz WiFi
Following are the benefits or advantages of 5 GHz WiFi system:
➨It offers fast speed which is about 1300 Mbps (~1.3 Gbps).
➨It supports higher bandwidth (20 MHz/40 MHz/80 MHz/160 MHz) in different WLAN standards.
➨It supports more number of channels than 2.4 GHz WiFi.
➨It suffers from less interference compare to 2.4 GHz WiFi version.
Drawbacks or disadvantages of 5 GHz WiFi
Following are the drawbacks or disadvantages of 5 GHz WiFi system:
➨It supports shorter coverage distances which is about 50 feet in indoor and 100 feet in outdoor.
➨The 5 GHz wifi devices and routers (i.e. APs) are more expensive.
➨The 5 GHz RF signal has lower wavelength and hence it can not easily pass through walls, floors and solid objects.
➨The network is not used by common wireless devices as it requires 5 GHz specific WiFi APs or routers.
WiFi-6 and WiFi-5 related links
advantages and disadvantages of 802.11ac (WiFi 5)
advantages and disadvantages of 802.11ax (WiFi 6)
BSS coloring in 11ax
RU in 802.11ax
MU-OFDMA in 802.11ax
MU-MIMO in 802.11ax
Difference between 802.11ac Wave1 and Wave2
Difference between 802.11n,11ac,11ad
WLAN 802.11ac tutorial
WLAN 802.11ax tutorial
WLAN 802.11ac frame structure
WLAN 802.11ac Physical Layer
802.11ac MAC Layer
WLAN 11a,11b,11n,11ac frame structures