Timi Technologies Co., Ltd.

Dong Bai

Wen Qing Chen

Qihong Ge

Tao Tao

Qinghua Yang

Qun Li

Hongbing Shen

Huishi Song

Qiusheng Wang

Yibin Liang

Junwei Wang

Binbin Liu

Lian Wang

Xiaowei Cao

Ruirui Ye

Fajun Yan

Guanbin Xing

Ju Ma

A mobile multimedia broadcast transmission system is provided, which comprises: a Reed-Solomon (RS) coding and byte interleaving unit, a Low Density Parity Check (LDPC) coder, a bit interleaver, a constellation mapping unit, a frequency domain symbol generator, a scrambler, an Inverse Fast Fourier Transform (IFFT) unit, a time domain framing unit, and a transmitter. According to the technical solutions provided in the present invention, the system can provide high-quality mobile multimedia services for users in a 6 MHz operation bandwidth. Furthermore, an optimized selection is performed on RS coding according to the operation bandwidth of the system, thereby selecting an appropriate coding mode according to different channel conditions. Accordingly, the byte interleaver is optimized, such that suitable interleaving parameters can be used to perform byte interleaving. With the technical solutions provided in the present invention, the continuous pilots, the discrete pilots and the digital sub-carriers of the system can be suitably configured and allocated according to the actual bandwidth of the system, thereby suitably configuring the system overhead of the mobile multimedia broadcast transmission system to efficiently utilize spectral resources for data transmission.

Mobile multimedia broadcast transmission system

The present invention discloses a multi-carrier digital multimedia broadcast system and the digital information transmission method thereof. After RS encoding and byte interleaving, LDPC encoding, bit interleaving and constellation mapping to an upper layer of data streams in turn, the obtained data symbol is multiplexed with scattered pilots and continual pilots which include the system information to form an OFDM frequency domain symbol and scrambled; an OFDM time domain symbol is generated by IFFT transforming, and after inserted with the frame head to build a time slot, it is connected to form a signal frame of the physical layer; the signal frame of the physical layer is transmitted after being low-pass filtered and orthogonal upconverted. The system and method thereof provide wireless broadcast with high quality such as audio, video and multimedia data and the like for mobile, fixed and portable receivers, and can use the satellite transmission and terrestrial transmission method for transmitting. The method utilizes the LDPC OFDM scheme, and the system applies the microwave and large scale integrated circuit technologies while fulfills the needs for low cast and high performance.

Multi-carrier digital mobile multimedia broadcast system and the digital information transmission method thereof

The present invention provides a method for transmitting/receiving a continuous pilot code in a multi-carrier system. The method for transmitting comprises: performing a time-frequency domain two dimensional encoding on an information bit stream to be transmitted; mapping the encoded bit stream to obtain a continuous pilot carrying encoding information; multiplexing a load, a discrete pilot and the mapped continuous pilot carrying the encoding information based on distribution of the load, the discrete pilot and the continuous pilot on a sub-carrier, to generate a frequency domain signal; and performing a frequency-time domain transforming on the generated frequency domain signal, to obtain a time domain sample. The method for receiving comprises: extracting the continuous pilot from an active carrier of a multi-carrier signal; and performing a time-frequency domain decoding on the extracted continuous pilots to obtain the decision of transmitted information bits. The invention ensures reliable transmission of the information without using additional bandwidth resource by carrying information in the continuous pilots using an encoding scheme.

Method and apparatus for transmitting/receiving a continuous pilot code in a multi-carrier system

The present invention relates to a method for constructing LPDC code check matrix and encoding and decoding devices using the same. The present invention constructs the LDPC code check matrix using an algebraic structure, obtaining the LDPC code with stable performance.

Method for constructing checking matrix of LDPC code and coding amd decoding apparatus utilizing the method

An efficient general QC-LDPC code decoder includes a general-purpose processor for distributing the storage storage space of the data memory block, and establishing an index for data addressing; a data memory block for storing the information used during decoding; a hardware accelerator for conducting part or all of the information processing operations including parity check, check node updating and variable node updating. A corresponding QC-LDPC code decoding method includes initializing the variable node information and performing parity check on the check matrix row block by row block; updating the check node row block by row block and updating the variable node column block by column block if any check equation is not met.

QC-LDPC code decoder and corresponding decoding method

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.

System and method for generating and detecting the identifier sequence of the bandwidth-limited transmitter

A method for transmitting control information to indicate a receiver, comprising following steps: the control information is formed at transmitting side and is encoded based on the working status of the transmitting side of the system; after the encoded control information is mapped, it is multiplexed with other pilot symbol and service load, then an OFDM symbol is generated; the OFDM symbol is transformed from frequency domain to time domain, then a time domain sampling signal is obtained and transmitted to the receiving side of the system; at the receiving side, the time domain sampling signal transmitted by the transmitting side is received and transformed from time domain to frequency domain to form OFDM symbol; the control information is obtained from the valid sub carrier of the OFDM symbol, and the control information is decoded; each work information is extracted form the decoded control information, and the receiving terminal is indicated to execute respective receive process based on the extracted work information. The method can ensure the receiving terminal to receive data based on its own expectation, then reduces the work power consumption of the receiving terminal, and saves the run cost of the digital broadcast system.

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Beijing, China

Dong Bai