Term Bandwidth Use in Event WiFi

1. WiFi Frequency Bands

WiFi operates primarily over two frequency bands: 2.4 GHz and 5 GHz. Each of these bands has different characteristics that affect bandwidth usage.

2.4 GHz Band:

• Range: Offers better coverage but is more susceptible to interference (e.g., from microwave ovens, Bluetooth devices).
• Bandwidth: Typically supports up to 72 Mbps (in standard 802.11g/n) and 600 Mbps in 802.11n (MIMO – Multiple Input, Multiple Output technology).
• Interference: The 2.4 GHz band is crowded due to its use by various other devices, leading to potential network slowdowns.

5 GHz Band:

• Range: Provides faster speeds but has a shorter range compared to the 2.4 GHz band.
• Bandwidth: Can support higher speeds, up to 1.3 Gbps with 802.11ac and 2 Gbps with 802.11ax (Wi-Fi 6) depending on channel width and device capabilities.
• Less Interference: The 5 GHz band is generally less congested, leading to less interference and more stable performance.

2. WiFi Standards and Bandwidth

WiFi standards dictate the maximum bandwidth achievable on a network. The key standards currently in use are:

802.11a/b/g/n/ac/ax:

• 802.11a/b/g: Older standards that support lower speeds, with a maximum bandwidth of 54 Mbps for 802.11g and up to 11 Mbps for 802.11b.
• 802.11n: Introduced MIMO technology, allowing for faster speeds (up to 600 Mbps under optimal conditions).
• 802.11ac: Known as Wi-Fi 5, this standard operates on the 5 GHz band and can support speeds up to 1.3 Gbps.
• 802.11ax: Wi-Fi 6, the latest standard, significantly improves efficiency and speed, supporting up to 10 Gbps across both 2.4 GHz and 5 GHz bands, with more efficient spectrum management and reduced congestion.

3. Channel Width

The channel width plays a critical role in determining available bandwidth for WiFi networks. A channel refers to the frequency range used by WiFi signals. Larger channel widths enable faster data transfer rates but are more susceptible to interference.

• 20 MHz: The standard channel width used in 802.11b/g/n, typically providing moderate speeds.
• 40 MHz: Common in 802.11n, offering a significant increase in bandwidth over 20 MHz, with speeds up to 300 Mbps.
• 80 MHz: Supported by 802.11ac, providing even faster speeds (up to 1 Gbps).
• 160 MHz: Available in 802.11ac and Wi-Fi 6, offering up to 2 Gbps speeds, but it requires a clean spectrum with minimal interference.

4. Multiple Input Multiple Output (MIMO)

MIMO is a technology that allows multiple antennas to transmit and receive data simultaneously, increasing the data throughput of a WiFi connection. MIMO helps in increasing bandwidth efficiency, especially in environments with heavy traffic.

• Single-Stream MIMO: One antenna is used to transmit and receive data, limiting the throughput.
• Multi-Stream MIMO: Multiple antennas are used to transmit and receive multiple data streams, significantly increasing bandwidth. This is common in 802.11ac and 802.11ax (Wi-Fi 6) devices, where up to 8 streams can be used.

5. QAM (Quadrature Amplitude Modulation)

QAM is a modulation technique used to encode data into radio waves. It defines how many bits can be transmitted per symbol.

• 16-QAM: Used in older standards like 802.11b/g, where each symbol carries 4 bits of data.
• 64-QAM: Used in 802.11n and 802.11ac, carrying 6 bits of data per symbol.
• 256-QAM: Found in 802.11ac and Wi-Fi 6, where each symbol carries 8 bits of data, allowing higher throughput.
• 1024-QAM: A new addition in Wi-Fi 6, supporting up to 10 bits per symbol, further enhancing data rates.

6. Signal-to-Noise Ratio (SNR)

The Signal-to-Noise Ratio (SNR) refers to the ratio of signal power to noise power in the network. A higher SNR indicates a clearer signal and more reliable connection, allowing for greater bandwidth utilization.

• Low SNR: Results in poor signal quality and reduced bandwidth, often leading to slower speeds or disconnections.
• High SNR: Ensures a clearer, more stable connection with higher data throughput.

7. WiFi Interference

Interference from other electronic devices and neighbouring WiFi networks can reduce the effective bandwidth of your WiFi network. Common sources of interference include:

• Microwave ovens
• Bluetooth devices
• Other WiFi networks
• Physical obstructions like walls and floors

Effective channel planning, reducing interference, and using technologies like beamforming (focusing the signal in a specific direction) can help mitigate these issues and improve available bandwidth.

8. Bandwidth Management

For event spaces, where large numbers of devices may be connected simultaneously, bandwidth management becomes essential. Techniques such as Quality of Service (QoS) can prioritise critical traffic, like security camera feeds or live streaming, over less important traffic, like web browsing.

9. Load Balancing and Traffic Shaping

Load balancing helps distribute traffic across multiple access points and channels to prevent congestion. This ensures that no single AP or channel is overloaded. Traffic shaping refers to the technique of controlling the flow of data to ensure optimal bandwidth usage and prevent any one service or device from overwhelming the network.