摘要:
The present invention relates to a catalyst for the synthesis of organic carbonates, the preparation of the catalyst and the application of this catalyst in the synthesis of organic carbonates from reacting urea and hydroxyl group containing compounds. The catalyst provided in this invention is a calcinate of hydrous salt containing rare earth element at a moderate calcining temperature.
摘要:
A system and method for generating and detecting identifier sequence of a bandwidth-limited transmitter are disclosed, comprising an identifier sequence generating portion and a detection portion. The identifier sequence generating portion comprises: generating a frequency-domain random sequence; generating a frequency-domain orthogonal sequence; performing frequency-domain truncation; performing frequency-time transformation; and performing cycle extension. The identifier sequence receiving portion comprises: truncating the time-domain for the received signal; performing time-frequency domain transformation to obtain a frequency-domain signal; generating frequency-domain random sequence; generating a frequency-domain orthogonal sequence; correlating the frequency-domain orthogonal sequence with the frequency-domain signal de-scrambled by the frequency-domain random sequence; and detecting an output from a frequency-domain correlator by a threshold detecting device and determining the transmitter identifier sequence. The random sequence bandwidth generated by the system and the method of the present invention can be configured flexibly according to transmission bandwidth requirement, and the sequence may be arbitrarily allocated at the power of each frequency point inside the bandwidth. The present invention may be widely applied to multimedia broadcasting, terrestrial radio broadcasting, cable broadcasting and the like.
摘要:
The present invention relates to a catalyst for the synthesis of organic carbonates, the preparation of the catalyst and the application of this catalyst in the synthesis of organic carbonates from reacting urea and hydroxyl group containing compounds. The catalyst provided in this invention is a calcinate of hydrous salt containing rare earth element at a moderate calcining temperature.
摘要:
A method for multiplexing a broadcast service channel and a non-broadcast service channel includes: reserving TF resources for carrying non-broadcast service data on a sub-frame for carrying broadcast service data, and multiplexing the broadcast service data and the non-broadcast service data to the sub-frame for carrying the broadcast service data. Correspondingly, a device for multiplexing a broadcast service channel and a non-broadcast service channel is disclosed. Hence, the system signaling overhead occupied during a TDM process between broadcast service and Unicast service is reduced, and the transmission delay of Unicast service is reduced.
摘要:
The present invention relates to the field of communication technology. A channel estimation device for an Orthogonal Frequency Division Multiplexing (OFDM) system is provided for performing channel estimation on data based on synchronization signal and pilot, which comprises: a synchronization signal based initial channel estimation module for performing initial channel estimation based on a synchronization signal in the data; a pilot channel tracking module for performing pilot channel tracking on the result of the initial channel estimation; a noise reduction module for performing noise reduction on the result of the pilot channel tracking; and an effective sub-carrier extraction module for extracting channel estimation values of effective sub-carriers from the result of the noise reduction. With the channel estimation method and device for OFDM system according to the present invention, the channel estimation is carried out jointly based on the synchronization signal and the pilot, such that the accuracy of channel estimation can be significantly improved and the performance requirements of the system can be satisfied without increasing the density of pilots and thus reducing the amount of system payload. Moreover, the synchronization signal can still be used for its original purpose of carrier and timing synchronization.
摘要:
The embodiments of the present invention provide a method of constructing parity-check matrix of LDPC code. The method comprises the following steps of: constructing a MB×NB base matrix B for an LDPC code with code rate R and code length N, wherein MB=M/K, NB=N/K, M=N (1−R), K is the expansion factor of the base matrix, Kεφ, and φ is the set of the common factors of M and N; and replacing the elements of the base matrix B with a K×K matrix, and expanding the base matrix B into a parity-check matrix H with size of M×N for the encoding or decoding of the LDPC code. An encoding method and apparatus of LDPC code are also provided by the embodiments of the present invention. The technical solutions provided by the embodiments of the present invention can construct LDPC codes with good performance, solve the storage problem of the parity-check matrix, and effectively reduce the implementation complexity of the encoding apparatus.
摘要翻译:本发明的实施例提供了一种构造LDPC码奇偶校验矩阵的方法。 该方法包括以下步骤:为码率为R和码长N的LDPC码构建MB×NB基本矩阵B,其中MB = M / K,NB = N / K,M = N(1-R) ,K是基本矩阵的扩展因子,K&egr&&phgr;和&phgr; 是M和N的共同因素的集合; 并且用K×K矩阵代替基本矩阵B的元素,并且将基本矩阵B扩展成具有M×N大小的奇偶校验矩阵H以进行LDPC码的编码或解码。 本发明的实施例也提供了LDPC码的编码方法和装置。 本发明实施例提供的技术方案可以构建具有良好性能的LDPC码,解决奇偶校验矩阵的存储问题,有效降低编码装置的实现复杂度。
摘要:
A method and device for service time division multiplexing as well as a method and a device for transmitting service are disclosed. The method for service time division multiplexing includes: selecting a part or all of radio frames in one time unit as specific radio frames; and selecting a part or all of subframes in the specific radio frames as specific subframes for sending a specific service. The specific service is a multimedia broadcast multicast service, or a unicast service, or one or more than one kind of services transmitted in broadcast or multicast mode.
摘要:
A method and device for service time division multiplexing as well as a method and a device for transmitting service are disclosed. The method for service time division multiplexing includes: selecting a part or all of radio frames in one time unit as specific radio frames; and selecting a part or all of subframes in the specific radio frames as specific subframes for sending a specific service. The specific service is a multimedia broadcast multicast service, or a unicast service, or one or more than one kind of services transmitted in broadcast or multicast mode.
摘要:
A method and device for service time division multiplexing as well as a method and a device for transmitting service are disclosed. The method for service time division multiplexing includes: selecting a part or all of radio frames in one time unit as specific radio frames; and selecting a part or all of subframes in the specific radio frames as specific subframes for sending a specific service. The specific service is a multimedia broadcast multicast service, or a unicast service, or one or more than one kind of service transmitted in broadcast or multicast mode.
摘要:
A method and device for service time division multiplexing as well as a method and a device for transmitting service are disclosed. The method for service time division multiplexing includes: selecting a part or all of radio frames in one time unit as specific radio frames; and selecting a part or all of subframes in the specific radio frames as specific subframes for sending a specific service. The specific service is a multimedia broadcast multicast service, or a unicast service, or one or more than one kind of service transmitted in broadcast or multicast mode.