Wi-Fi's physical layer (PHY) standard is defined within the IEEE 802.11 set of standards.
The IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard is a crucial part of the larger IEEE 802 set of standards. These standards are focused on networking, specifically local area networks (LANs). Within IEEE 802.11, there are specifications for both the medium access control (MAC) layer and the physical layer (PHY) protocols that allow devices to communicate wirelessly.
Here's a breakdown:
| Layer | Description | Details |
|---|---|---|
| MAC (Medium Access Control) | Governs how devices share the wireless medium | Manages when devices can transmit data, handling collision avoidance and data transmission timing. |
| PHY (Physical Layer) | Deals with the actual transmission and reception of data signals. | Specifies things like modulation techniques, frequencies, power levels, and encoding methods. This ensures the radio signals carrying the information are correctly transmitted and received. |
Essentially, the PHY layer under the IEEE 802.11 standard dictates:
- How data is converted into radio waves
- The frequencies used for transmission (e.g., 2.4 GHz, 5 GHz, 6 GHz)
- The modulation methods employed (e.g., OFDM, QAM)
- Power levels for communication.
So, while many different technologies are under the *Wi-Fi* umbrella, they all rely on the core IEEE 802.11 standard for both their MAC and PHY implementations. Examples of different *Wi-Fi* standards based on 802.11 include 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax (Wi-Fi 6) with each new standard enhancing speed and efficiency through advancements at both the MAC and PHY layers.
