Abstract: A high temperature and high salinity-resistant complementarily rigid-flexible plugging agent, a method for preparing the same, and a water-based drilling fluid and a use thereof.

Abstract: A polar code construction method and an apparatus. A communication apparatus obtains a reliability weight sequence, and determines a first threshold that indicates a weight of lowest reliability of a subchannel corresponding to an information bit. The communication apparatus determines a non-pre-frozen subchannel corresponding to a content value greater than or equal to the first threshold in the reliability weight sequence as the subchannel corresponding to the information bit based on the first threshold, and performs polar coding on the information bit based on the subchannel corresponding to the information bit.

Abstract: An encoding method, a decoding method, and an apparatus. A symbol quantity S is determined based on an encoding bit quantity L and an energy level quantity B, where S is S1 or S2, S1=L/B, and S2=L/2B. K information sub-channels are determined from an encoding sequence based on the symbol quantity S, the energy level quantity B, and a reliability sequence. K information bits are encoded and a bit sequence is output based on the K information sub-channels, where the K information sub-channels are selected from candidate sub-channels based on an order of reliability of the candidate sub-channels. The candidate sub-channels are S1 sub-channels or 2×S2 sub-channels in a sub-sequence whose energy level is i in the encoding sequence.

Abstract: A resource mapping method and apparatus are described that reduce resource mapping complexity. The method includes an access network device obtaining resource mapping information of at least one terminal, and sending the resource mapping information to the at least one terminal respectively. The resource mapping information indicates a resource element RE to which each of the at least one terminal performs mapping in each RMB in a first resource mapping block RMB set. An RE to which a first terminal performs mapping in each RMB in the first RMB set is determined based on a first interleaved sequence, and the first interleaved sequence is determined based on a base sequence. The first terminal is any one of the at least one terminal, and the first RMB set includes at least one RMB.

Abstract: Embodiments of systems and methods for dicing a bonded structure are provided. A method for dicing a bonded structure includes thinning a top surface and a bottom surface of a bonded structure. The bonded structure may have a first wafer and a second wafer bonded with a bonding interface. The method may also include forming a series of ablation structures in the first wafer and the second wafer. The series of ablation structures may be between a first part and a second part of the bonded structure. The method may also include separating the first part and the second part of the bonded structure along the series of ablation structures.

Abstract: The present invention discloses a driving current correction method and apparatus for multiple laser devices, and a laser projector.

Abstract: A dynamic loose vehicle formation method based on real-time online navigation map, which belongs to the field of vehicle formation technologies. The method includes a driver inputs travel information of a destination and waypoints in a GIS app; the GIS app uploads the travel information to a GIS server; the driver chooses to join a recommended formation or create a formation in the GIS app; when the driver chooses the formation and joins the formation, the formation information is displayed on the GIS app interface and sent to other vehicles within the formation for information interaction; when the driver chooses to leave the formation and leaves the formation, the formation is adjusted and the GIS server updates the formation information.

Abstract: According to a first aspect of the disclosure, methods are discussed in which a station (STA) sends a message to an access point, for example an associated access point, about a change in multi-AP coordination parameters. A STA, which may be a mobile STA, can be in a better position than the APs themselves, for detecting changes in conditions which can affect the effectiveness, or even the desirability of the multi-AP coordination. Accordingly the STA can send a message reporting detected conditions related to multi-AP coordination. In some embodiments, such a message can request for initializing multi-AP coordination, such a message can be in response to a triggering event detected by the STA. In response to such a triggering event, the STA can analyze the STA's service needs, and send the message about a change in multi-AP coordination parameters. A second aspect of the disclosure provides an AP-to-AP negotiation process for multi-AP coordination.

Abstract: This application discloses a modulation method, a demodulation method, and a communication apparatus, and relates to the field of communication technologies. The communication apparatus may obtain information bit sequences, divide the information bit sequences into G groups, then separately encode each group of information bit sequences to obtain r encoded bit sequences, map the r encoded bit sequences into a modulation symbol sequence, and output the modulation symbol sequence. The modulation method provided in embodiments of this application may implement a flexible compromise between complexity and robustness, and has a wider range of application.

Abstract: A method for preparing low-background cement includes: uniformly mixing a seed crystal of cement, C4AF whiskers, and high-magnesium raw material to yield a first mixture, calcining the first mixture at 1400-1500° C., to yield a low-background clinker, the first mixture including 1.0-5.0 wt. % of the seed crystal of cement, 1.0-5.0 wt. % of the C4AF whiskers, and the balance is the high-magnesium raw material; and grinding a second mixture of the low-background clinker and gypsum, to yield low-background cement. The seed crystal of cement is a high-magnesium and low hydration heat clinker, has a specific activity of Ra-226 radioactive nuclides within 50 Bq/kg, and the MgO content of the clinker is between 4.0 wt. % and 5.0 wt. %, with 50 wt. % <C3S <55.0 wt. %; and the high-magnesium raw material has a MgO content between 2.5 wt. % and 3.0 wt. %.

Abstract: A coding method and apparatus are provided. The method includes: coding an information bit by using a preset generator matrix of a systematic (U|U+V)-code to obtain a codeword of a systematic code. The preset generator matrix of the systematic (U|U+V)-code includes a first identity sub-matrix of a U code and a second identity sub-matrix of a V code. A plurality of elements in a same column as the first identity sub-matrix are all 0. A plurality of elements in a same column as the second identity sub-matrix are all 0.

Abstract: Embodiments of this application relate to the field of communications technologies, and provide an encoding and decoding method and apparatus, to reduce encoding/decoding complexity and improve encoding/decoding performance. In the method, a transmit device may obtain N to-be-encoded vectors. The transmit device may encode the N to-be-encoded vectors based on a polar code kernel matrix, to obtain N temporary code blocks. The transmit device may respectively perform a mask operation on target bit sequences in an (n+1)th temporary code block to an (n+M)th temporary code block and a source bit sequence segment of an nth temporary code block, to obtain M mask bit sequences. The transmit device may respectively encode the M mask bit sequences based on the polar kernel matrix, to obtain M encoded mask bit sequences. The transmit device may sum the M encoded mask bit sequences and M temporary code blocks, to obtain M first code blocks.

Abstract: This application provides a polar encoding and modulation method and apparatus, and a demodulation and decoding method and apparatus. In the polar encoding and modulation method, a probability shaping technology is combined with a polar code, to group to-be-encoded bit sequences, and probability shaping is performed on a group of bit sequences. Modulation and mapping are directly performed on all bit sequences obtained through probability shaping, and polar transformation is performed on some bit sequences obtained through probability shaping together with other groups of bit sequences for modulation and mapping. In the demodulation and decoding method, a modulation symbol sequence is demodulated and decoded, a part of obtained bit sequence is directly mapped to obtain a second bit sequence, and the other part is continuously decoded to obtain a first bit sequence.

Abstract: A sending device may obtain a first to-be-encoded vector. The sending device may perform first encoding on the first to-be-encoded vector, to obtain a second to-be-encoded vector. The sending device may encode the second to-be-encoded vector based on a first generator matrix, to obtain an encoded codeword. The first generator matrix may include at least N+1 submatrices a, and N of the submatrices a may be located on a main diagonal of the first generator matrix. The first generator matrix may be a block upper triangular matrix, or the first generator matrix may be a block lower triangular matrix. The submatrix a is a polar kernel matrix with a size of 2m*2m, m is a natural number, and N is a natural number. The sending device may send the encoded codeword.

Abstract: A method for determining an auxiliary bit of a polar code and an apparatus. At least K sub-channels are determined based on reliability of a first sub-channel set, where the K sub-channels carry information bits. S sub-channel subsets are determined based on the first sub-channel set, an ith sub-channel subset in the S sub-channel subsets includes Ji sub-channels carrying auxiliary bits and Ki sub-channels in the K sub-channels. Sequence numbers of the Ji sub-channels carrying the auxiliary bits are after sequence numbers of the Ki sub-channels. The auxiliary bits are known redundancy check RC bits. Polar encoding is performed on the information bits and the auxiliary bits, to output polar-encoded data.

Abstract: An encoding method includes, when a first code rate K/Nmax is less than or equal to a code rate threshold Rt, reading a first matrix from a preset code table based on a second matrix. The second matrix includes a matrix that is read from the preset code table and that corresponds to a maximum supported code length Nmax and Rt, where K is an integer and N is an integer. The method also includes reading K rows and (N?K) columns starting from a preset first location in the first matrix to obtain a third matrix. The method further includes adding a unit matrix with K rows and K columns to a left side of the third matrix to obtain a generator matrix of an (N, K) linear block code. K rows and (Nmax?Nmax×Rt) columns of the second matrix in a first direction are consistent with K rows and (Nmax?Nmax×Rt) columns of the first matrix in a second direction.

Abstract: An encoding method and apparatus are provided, to propose a construction and encoding scheme of a BCH code. A code length and a code rate of an obtained BCH code are flexible, to satisfy a requirement of flexible channel encoding in wireless communication. The method includes determining a first encoding parameter based on a first BCH code, where the first BCH code is a to-be-coded BCH code, the first encoding parameter is a first code or a generator matrix of a first code, the first code has a code length of n and an information bit length of k, n is greater than o, and k is greater than o, and performing BCH encoding based on the first encoding parameter.

Abstract: The present disclosure provides for methods and systems for improved channel information gathering mechanism. An aspect of the disclosure provides a method. The method includes sending, to one or more stations (STAs), a request for channel information. The channel information being related to one or more channels between an access point (AP) and the one or more STAs. The method further includes receiving, from the one or more (STA), one or more physical layer (PHY) protocol data units (PPDUs). The PPDUs includes channel feature information (CFI) associated with the one or more channels. In some embodiments, the request includes a beamforming report poll (BFRP) trigger frame having a user information field. The user information subfield indicating one or more thresholds associated with one or more parameters of the channel feature information.

Abstract: Embodiments disclose an encoding method and a communications device. The method includes: obtaining and encoding a to-be-encoded information bit sequence based on a binary vector P1 of a first code, to obtain and output an encoded bit sequence, where P1 is determined based on a binary vector P2 of a second code and a binary vector P3 of a third code, P1, P2, and P3 indicate an information bit and a frozen bit of the first code, the second code and the third code respectively, a code length of the first code, the second code and the third code is n1, n2 and n3 respectively, a quantity of information bits of the first code, the second code and the third code is k1, k2 and k3 respectively, n1=n2*n3, and k1=k2*k3. Therefore, parallel decoding can be performed, helping reduce a decoding delay.

Abstract: This application provides a coding method and apparatus.