High Throughput (HT) and Very High Throughput (VHT) are terms associated with the evolution of Wi-Fi standards, specifically pertaining to the IEEE 802.11n (Wi-Fi 4) and IEEE 802.11ac (Wi-Fi 5) standards, respectively. These standards introduce improvements in data rates, channel bonding, and other technologies to enhance the overall throughput and performance of Wi-Fi networks.
High Throughput (HT) – IEEE 802.11n (Wi-Fi 4):
- Introduction:
- High Throughput (HT) is a feature introduced in the IEEE 802.11n standard, designed to provide higher data rates and improved performance compared to earlier Wi-Fi standards.
- Key Features:
- Channel Bonding: HT allows the aggregation of multiple adjacent channels to increase the available bandwidth. This is known as channel bonding, and it enhances data rates by enabling the simultaneous transmission of multiple data streams.
- MIMO (Multiple Input, Multiple Output): HT supports MIMO technology, allowing multiple antennas at both the transmitter and receiver ends. MIMO improves signal quality, range, and data rates by exploiting spatial diversity.
- Advanced Modulation Schemes: HT introduces more advanced modulation schemes, such as 64-QAM (Quadrature Amplitude Modulation), which allows the transmission of more data bits per symbol, increasing overall throughput.
- Frame Aggregation: HT incorporates frame aggregation techniques, enabling the grouping of multiple frames into a single transmission unit. This reduces overhead and improves efficiency.
Very High Throughput (VHT) – IEEE 802.11ac (Wi-Fi 5):
- Introduction:
- Very High Throughput (VHT) is the next evolution of Wi-Fi standards, introduced in the IEEE 802.11ac standard. It builds upon the foundation laid by HT and introduces further enhancements to achieve even higher data rates and improved performance.
- Key Features:
- Wider Channels: VHT supports wider channel bandwidths, including 80 MHz and 160 MHz channels. This significantly increases the available spectrum for data transmission.
- Additional Spatial Streams: VHT extends MIMO capabilities by supporting a higher number of spatial streams. This allows for even more parallel data transmission, further improving throughput.
- Advanced Modulation: VHT introduces higher-order modulation schemes, including 256-QAM, enabling the transmission of more data bits per symbol and increasing the overall data rate.
- Multi-User MIMO (MU-MIMO): VHT introduces MU-MIMO, allowing a Wi-Fi access point to communicate with multiple devices simultaneously. This enhances the efficiency of the network in scenarios with multiple connected devices.
Summary:
In summary, both High Throughput (HT) and Very High Throughput (VHT) represent significant advancements in Wi-Fi standards, introducing technologies such as channel bonding, MIMO, advanced modulation, and wider channels to achieve higher data rates and improved overall performance. VHT, being a later standard, builds upon the foundation laid by HT, bringing additional features like wider channels and MU-MIMO to further enhance the Wi-Fi experience. These advancements play a crucial role in meeting the growing demand for faster and more efficient wireless connectivity.