In Wi-Fi 7 (802.11be), DUP (Duplicated Transmission) is an enhanced transmission mechanism used to improve the reliability and efficiency of data transmission, especially in high-interference environments. The following will explain the DUP transmission process and its significance in detail, and give a specific example to illustrate the process.
Definition and process of DUP Transmission
definition： DUP (Duplicated Transmission) transmission is a mechanism for sending the same data on multiple channels simultaneously to ensure that the data can be transmitted and received more reliably. In Wi-Fi 7, this mechanism is implemented by repeatedly transmitting the same PPDU (Physical Protocol Data Unit) on different channels.
It should be noted that DUP Transmission is an optional implementation and can only be implemented in 6GHz. It has regulations on bandwidth, modulation mode, bit rate and number of streams. It does not support preamble puncturing and can only be performed under SU conditions.
process：
Channel Selection: The sender (usually an AP) selects multiple channels for DUP transmission. The channels can be contiguous or non-contiguous, depending on the available channels and channel conditions.
Data replication: The AP copies the data packet to be sent into multiple PPDUs, and each PPDU is transmitted on a different channel.
Simultaneous transmission: The AP sends these duplicate packets simultaneously on multiple channels.
Receiving and merging: The receiving end (usually a client device) receives these PPDUs simultaneously on multiple channels and merges the packets from different channels to ensure complete reception.
The significance of DUP Transmission
Improve reliability: In a high interference environment, a single channel may be interfered or signal attenuated, resulting in data loss. By repeatedly transmitting the same data on multiple channels, the success rate of receiving data can be increased and the possibility of data loss can be reduced.
Enhanced robustness of data transmission: Repeatedly transmitting data on different channels can effectively resist instantaneous interference and multipath effects, ensuring that data can be successfully received under different environmental conditions.
Optimizing spectrum utilization: In some cases, some channels may be subject to greater interference or poor signal quality. Through DUP transmission, multiple channels can be flexibly utilized to improve overall transmission efficiency.
Example of DUP Transmission process
Assume that an AP needs to transmit a video stream to a client device and there is high radio interference in the current environment. The AP decides to use DUP transmission to improve transmission reliability.
Channel Selection: The AP selects three non-contiguous channels (channel 1, channel 6, and channel 11) for DUP transmission.
Data replication: The AP copies the video stream data packet into three identical PPDUs and prepares them for transmission on channel 1, channel 6, and channel 11 respectively.
Simultaneous transmission: The AP sends these duplicate PPDUs simultaneously on channel 1, channel 6, and channel 11.
Receiving and merging：The client device receives PPDU on these three channels simultaneously. On channel 1, some data is damaged due to interference; on channel 6, the data is received completely; on channel 11, a small amount of data is lost.
Data Merge: The client device merges the complete data from channel 6 and the partial data from channel 11 to complete the data lost on channel 1, and finally successfully receives the complete video stream data.
in conclusion
DUP Transmission is an important transmission mechanism in Wi-Fi 7. It improves the reliability and robustness of data transmission by repeatedly transmitting the same data on multiple channels. It is particularly suitable for high-interference environments and data transmission scenarios that require high reliability. Through specific examples, you can better understand its working process and advantages in practical applications.
