Abstract: A multi-link device (MLD) has a medium access control (MAC) layer management entity (MLME) and a station management entity (SME). The SME indicates a selected link identity (ID) to the MLME. The selected link ID is used to indicate the link being used for frame exchange between an access point (AP) affiliated with an AP MLD and a non-AP station (STA) affiliated with a non-AP MLD. One or more frames are exchanged through the link indicated by the selected link ID.

Abstract: This application provides a communication method and apparatus, and relates to the communication field. The method includes: generating a physical layer protocol data unit PPDU, where the PPDU includes a first field indicating that the PPDU is an extremely high throughput sounding null data packet EHT sounding NDP transmitted based on orthogonal frequency division multiple access OFDMA, the PPDU further includes an extremely high throughput-long training field EHT-LTF and a packet extension PE field, and the PE field is adjacent to the EHT-LTF; and sending the PPDU. In this way, a Bfee may determine, based on the first field in the PPDU, that the PPDU is the EHT sounding NDP transmitted based on OFDMA, perform channel estimation by using the PPDU, and feed back channel state information to a Bfer, to implement functions such as beamforming and resource scheduling for OFDMA transmission, thereby improving channel quality and a throughput.

Abstract: A volumetric receiver vessel for heating a fluid with concentrated solar radiation which includes: an external housing having an aperture at the front end; an internal housing separating fluid entering the vessel from fluid exiting thereof; a window covering the aperture of the vessel, where the window closes and seals the aperture of said vessel against a non-metallic seal; and a radiation absorber, located inside the vessel and places to absorb radiation entering the vessel through said window on a radiation absorbing surface, where said surface include at least two zones with different radiation absorption coefficients.

Abstract: A method and system for reforming hydrocarbon gas, which includes stripping from the hydrocarbon gas at least most of gaseous impurities of a type and/or quantity which would normally interfere with efficient catalytic reforming in order to provide stripped hydrocarbon gas including carbon dioxide, optionally compressing the stripped hydrocarbon gas to provide compressed stripped hydrocarbon gas, and reacting the stripped hydrocarbon gas in a solar radiation receiving reactor having a catalyst that is heated by concentrated solar radiation impinging thereon, thereby providing an output gas mixture comprising hydrogen gas and carbon monoxide. The invention also includes a method and system for reforming hydrocarbons in a solar radiation receiver reactor, and such a system that also includes a certification system for certifying the amount and composition of the output gas mixture.