DRU Channel Sounding Using NDP LTFs in Wi‑Fi
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Solution Overview
Problem
Existing wireless networks fail to efficiently remove elemental mercury (Hg0) from waste liquid, with activated carbon injection technology being costly and its mercury removal efficiency is affected by NOx and SO2.
Innovation Solution
Utilization of metal sulfides (e.g., FeS2, CuS, CuS, CuS, CuS) as mercury removal adsorbents, which contact with flue gas and waste liquid, adsorbing and converting Hg0 from flue gas and Hg2+ from waste liquid into stable mercury sulfide compounds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If activated carbon injection technology is used for mercury removal, then mercury removal efficiency is improved, but operational costs increase
Solution Approach 1:
The patent replaces expensive activated carbon with inexpensive metal sulfide particles that can be injected directly into the flue gas stream. These metal sulfide adsorbents are far cheaper than activated carbon while providing effective mercury removal, directly addressing the cost issue in the contradiction.
Solution Approach 2:
The patent changes the chemical composition parameter from carbon-based activated carbon to metal sulfide compounds. This parameter change fundamentally alters the cost structure while maintaining or improving mercury removal efficiency through the high reactivity of metal sulfides with elemental mercury.
2Reliability
If activated carbon injection is used, then mercury removal is achieved, but mercury removal efficiency is affected by NOx and SO2
Solution Approach 1:
The patent exploits the specific chemical property of metal sulfides to selectively react with elemental mercury while being less affected by NOx and SO2. The local quality of metal sulfide reactivity toward Hg0 provides resistance against interference from other flue gas components.
Solution Approach 2:
The patent converts the presence of SO2 and NOx in flue gas from harmful interfering factors into beneficial conditions. The reducing atmosphere created by these gases actually enhances the effectiveness of metal sulfide adsorbents in capturing mercury, turning potential problems into advantages.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Achieves efficient, cost-effective, and environmentally friendly simultaneous removal of Hg0 from flue gas and Hg2+ from waste liquid, avoiding secondary pollution and reducing operational costs.
Implementation Method 1
metal sulfides (e.g., FeS2, CuS, CuS, CuS, CuS) as mercury removal adsorbents, which contact with flue gas and waste liquid, adsorbing and converting Hg0 from flue gas
Implementation Method 2
adsorbing and converting Hg0 from flue gas and Hg2+ from waste liquid into stable mercury sulfide compounds
Data Source
AI summary
Apparatus, methods and procedures of channel sounding are disclosed herein. In an example, an access point (AP) transmits, to a station (STA), a frame to solicit the transmission of a null data packet (NDP). The STA receives the frame. Further, the frame includes distributed resource unit (DRU) information indicating a DRU. The frame may be at least one of a control frame, management frame, or data frame. The STA transmits, to the AP, the NDP, which is received by the AP. Further, long training fields (LTFs) of the NDP are transmitted over a plurality of distributed tones of the DRU, and the DRU is indicated by the received DRU information. Accordingly, the channel sounding may be performed in a Wi-Fi system. In an example, the DRU information indicating the DRU may include a DRU allocation index field, or both a DRU allocation index field and a distribution bandwidth field.