The technical structure of Wi-Fi

Standards and Frequencies

The table below provides key information about Wi-Fi standards and frequencies.

OFDM, OFDMA

We will explain the main features of OFDM and OFDMA in Wi-Fi wireless transmission methods.

OFDM

OFDM (Orthogonal Frequency Division Multiplexing) is a modulation method used in the 802.11a standard.

OFDM characteristics

• Data is divided into multiple subcarriers for parallel transmission
• Increases overall channel utilization and improves wireless transmission speeds.
• Simultaneous use of subcarriers within one channel

OFDMA

OFDMA (Orthogonal Frequency Division Multiple Access) is a modulation technology newly introduced in Wi-Fi 6 (802.11ax).

OFDMA Features

• Improved OFDM, splitting the channel into smaller sub-channels
• Divided into the smallest unit (resource unit: RU) of approximately 2 MHz
• Multiple users can communicate simultaneously using different frequencies

Key Advantages of OFDMA

By adopting OFDMA, Wi-Fi 6 is strong in simultaneous connection of multiple devices and can now handle the increase in IoT devices and high-density communication environments.
This enables stable communications even in places where many devices are concentrated, such as offices and public facilities.

SISO, MIMO

We will explain the main characteristics of SISO and MIMO in Wi-Fi wireless transmission methods.

SISO

SISO (Single Input Single Output) is the most basic wireless communication method.

Characteristics of SISO

• One ANTENNAS is used for both the transmitter and receiver
• Simple configuration and low cost
• Data transmission speed is relatively slow
• Susceptible to radio interference and blockage

MIMO

MIMO (Multiple Input Multiple Output) is an advanced communication method that uses multiple ANTENNAS.

MIMO Features

• Use of multiple ANTENNAS at the transmitter and receiver
• Significantly improves data throughput and link distance
• High frequency band utilization efficiency
• Reduces fading and improves link reliability

MIMO (Multiple Input Multiple Output) has been adopted in Wi-Fi standards since Wi-Fi 4 (IEEE 802.11n), and the latest Wi-Fi 7 (IEEE 802.11be) supports 16 x 16 MU-MIMO (Multi-User Multiple Input Multiple Output).

Performance comparison

TKIP, AES

We will explain the main features of TKIP and AES Wi-Fi encryption methods.

TKIP:

TKIP (Temporal Key Integrity Protocol) is an improvement over the older encryption method WEP (Wired Equivalent Privacy).

Features of TKIP

• Higher encryption strength than WEP
• Increased security by using a different encryption key for each packet
• Since it inherits the basic mechanism of WEP, it cannot be said to be completely secure.

AES:

AES (Advanced Encryption Standard) is the encryption method with the strongest encryption strength currently available in Wi-Fi communications.

AES Features

• Further improvements to TKIP provide even stronger security
• Uses a 128-bit key length for extremely strong encryption
• The most recommended encryption method for modern wireless communications

Comparing TKIP and AES

If security is a concern, it is highly recommended to use AES encryption.
Many of the latest Wi-Fi devices support AES, allowing for a more secure wireless environment.