Southeast University

The Research Institute of Telecommunication Transmission, Mii

Huawei Technologies Co., Limited

Electronics and Telecommunications Research Institute

The Research Institute of Telecommunication

The Mitt Research Institute of Telecommunication Transmission

Chengdu T-ray Technology Co., Ltd.

Xiaohu You

Xiqi Gao

Liangcheng Jiang

Shixin Cheng

Wenjin Wang

Jinghong Guo

Chunming Zhao

Tao Li

Yalin Liu

Liang Wu

Dong-Seung Kwon

Jue Wang

Zaichen Zhang

Yuan Zhang

Seung-Jun Lee

Dongming Wang

Bin Jiang

Shi Jin

Guangguo Bi

Mao Wang

Yan Zhang

Haiming Wang

Yongming Huang

Bin Sheng

Ling Wang

Hengjie Hu

Junping Sun

Teer Ba

Jun Zou

Xutao Yu

Junchao Wang

Zhuming Deng

Xianggen Xia

Guochen Ou

Min Hua

Yanxiang Jiang

Zhiwen Pan

Zhangyong Ma

Dixian Zhao

Zhihui Chen

Huiqi Liu

In a method for coding on a time-space two-dimensional channels, the system expresses the coding method with code words, merges the code words to form a space-time two-dimensional codebook, stores the codebook at both ends of the sending terminal and the receiving terminal; the sending terminal selects the coding structure according to the code words, and encodes each data stream according to time-domain coding rates, and forms data blocks of an equal length in the time-domain through the rate matching. The system selects different code word serial numbers, rate matching tables and space time slicing modes according to the requirements of different scenarios for transmission rates, latency and code error rate, as well as channel states and size of data blocks; when a Time Space Concatenated Coding Mode is adopted, the sending terminal performs time-domain coding according to the time-domain slicing mode and the time-domain code words.

Method for coding on time space two dimensional channel

A communication method includes: determining, by a first device, a first synchronization signal, where the first synchronization signal is used by a second device for symbol timing alignment and frequency synchronization; and sending, by the first device, the first synchronization signal on each group of subcarriers of M groups of subcarriers, where M is a positive integer greater than or equal to 2. According to the communication method in this application, the first device sends the first synchronization signal on each group of subcarriers of a plurality of groups of subcarriers, so that the second device can select, based on a reception capability of the second device, an appropriate bandwidth to receive the first synchronization signal.

Communication method and device

A random access method and a device are provided, to enable a device in the Internet of Things to implement random access. The method includes: selecting, by a terminal from at least two frequencies, frequencies used to send a physical random access channel PRACH signal, as frequencies occupied by target PRACH resources, where the at least two frequencies each have a preset bandwidth, and there is no intersection between frequency bands of the at least two frequencies; generating, by the terminal, a target PRACH signal based on the frequencies occupied by the target PRACH resources, a root allocated by a base station, and a cyclic shift corresponding to the root allocated by the base station; and sending, by the terminal, the target PRACH signal to the base station on the target PRACH resources.

Random access method and device

Disclosed is a main synchronization sequence design method for global covering multi-beam satellite LTE, comprising the follow steps: extending a standard Zadoff-Chu sequence to a generalized Zadoff-Chu sequence so as to obtain an initial candidate main synchronization sequence set of more candidate sequences; gradually narrowing down the candidate main synchronization sequence set according to a selection standard of a main synchronization sequence to obtain a final candidate main synchronization sequence set; and obtaining a main synchronization sequence set with optimal eclectic performance and complexity from the final candidate main synchronization sequence set. According to the present invention, a main synchronization sequence with optimal eclectic performance and calculation complexity can be designed for a global covering same-frequency networking multi-beam satellite LTE system.

Main synchronization sequence design method for global covering multi-beam satellite LTE

The present invention provides an Offset Modulation Orthogonal Frequency Division Multiplexing (OFDM) and multi-access transmission method with a Cyclic Prefix (CP), including a generating method of the sent signal in the sending terminal and a processing method of the received signal in the receiving terminal, the method includes: in the sending terminal, performing generalized discrete Fourier Transform on real-value digital baseband modulated symbols and obtaining the frequency-domain signal; performing conjugate symmetric extension, frequency-domain filtering, sub-carrier mapping on the frequency-domain signal; performing Inverse Fast Fourier Transform on the frequency-domain signal after sub-carrier mapping; inserting a CP and obtaining the time-domain sent signal; in the receiving terminal, including: removing the CP, performing Fast Fourier Transform on CP removed symbols and obtaining the frequency-domain received signal; and based on multiple user joint frequency-domain equalization performing iterative detection decoding on the frequency-domain received signal. The present invention can obtain the low-signal envelope volatility in the condition of remaining spectrum efficiency, and adopting iterative received signal processing method based on multiple user joint frequency-domain equalization ensures the transmission reliability with low-complexity.

Offset modulation orthogonal frequency division multiplexing (OFDM) and multi-access transmission method with cyclic prefix (CP)

A Space Division Multiple Access transmission method based on a statistical characteristic pattern including configuring multiple receiving and transmitting antennae at a base station side into one or more antenna arrays; comparing a diagonalization performance among the unitary matrixes for a correlation matrix of subscriber channels, with a long-time statistical correlation matrix of the subscriber channels at the base station side; calculating an optimal diagonalized correlation matrix, and then performing characteristic pattern clustering for the subscribers in a cell with the space resource divisions of the subscribers; grouping the subscribers that belong to a same characteristic pattern cluster into space division subscriber groups; carrying out SDMA transmission, by the subscribers in a same space division subscriber group, with their space resource divisions; dynamically performing subscriber characteristic pattern clustering and space division subscriber grouping described above to generate updated characteristic pattern clusters for the subscribers and updated space division subscriber groups.

Space division multiple access transmission method of statistical characteristic mode

A pilot and channel estimation method for SDMA MIMO transmission downlink is provided in the present invention, and the method provides possibility for saving the orthogonal pilot resources; the pilot signals of different users in the transmitting antenna domain can occupy the same time-frequency resources, and thereby the pilot overhead of system resources can be reduced greatly; the method includes: for the MIMO transmission downlink that employs pre-coding for SDMA, taking the quantity of orthogonal pilot resources occupied by the users in the pre-coding domain as the number of data streams that can be transmitted or the number of spatial dimensions occupied first, at the transmitting end of the base station; then, performing SDMA transmission pre-coding for the orthogonal pilots in the pre-coding domain in the same way as the data signals, to obtain the pilot signals of the users in the transmitting antenna domain; wherein, the pilots of the users in the pre-coding domain can be orthogonal in the frequency domain or code domain, and the pilots of different users in the pre-coding domain can be identical or not identical to each other; the pilot signals of different users in the transmitting antenna domain can occupy the same time-frequency resources.

Pilot and channel estimation method for SDMA MIMO transmission downlink

A synchronization method for impulse system ultra-wideband takes frame as basic unit for data transmission, each frame is divided into a preamble symbol part and a data part, wherein the preamble symbol part sends a known impulse sequence for channel estimation and synchronization; the data part takes the information to be transmitted; the preamble symbol part is divided into two parts of a positive and negative impulse sequence, which includes odd impulses with alternant positive and negative polarities, and a same direction impulse sequence, which is composed of impulses with same polarity and is the same as the polarity of the last impulse in the positive and negative impulse sequence. The method provides such advantages as high synchronization precision, small storage space, and capability of immediately finding out the synchronization position etc., and provides an important value for the development of the impulse system ultra-wideband wireless communication technique.

Synchronization method for impulse system ultra-wideband

For a demand of high speed, low cost and low power loss short distance wireless communication, a high-speed sampling and low-precision quantification pulse ultra-wideband wireless communication method is provided. A baseband narrow pulse sequence is generated at a transmission end using the digital technology by the method, and is transmitted after modulating amplifying and filtering and amplifying at a reception end, after the digital-signal processing of synchronizing, channel estimating, related detecting, and channel decoding, tec, is performed for the quantified data, the transmission information is retrieved. Comparing with the present carrier mechanism UWB wireless communication technology, the method does not need the complex radio frequency processing of orthogonal modulation/demodulation and frequency spectrum moving, etc, the quantification precision of analog-to-digital conversion is also decreased greatly, so the cost and power loss are greatly decreased; comparing with the present pulse mechanism UWB wireless communication technology, the method provided by the present invention greatly increase the data transmission rate, and increases the stability, reliability and integration.

High-speed sampling and low-precision quantification pulse ultra-wideband wireless communication method

An adaptive transmission scheme of the channel environment in the multi-antenna wireless transmission system can raise the spectrum use rate and power efficiency of the communication system. Compared with traditional single antenna input and single antenna output, the channel environment in MIMO wireless communication system is more complex. When the terminal is moving, the different types of channels between terminal and base station can be gone through and then its capacity can be changed more largely. Embodiments of the disclosure are directed to systems that transmit high speed data by way of a plurality of transmitting and/or receiving antennae, and particularly to a transmission scheme in different channel environments in a multi-antenna wireless transmission system.

Self-adapting transmission scheme of the channel environment in the multi-antenna wireless transmission system

A space domain filter detecting method in a multi-antennas wireless communication system, which processes time and space domain interference differently. The space domain filter detecting method comprises the following steps: firstly, the received signals are matched-combined in time domain and space domain; secondly, using the combined signals as an observation value, the space domain filtering is performed; thirdly, an estimated value is subtracted from the filtered signals, and the result is taken as a detection output, which is sent to a determiner in a non-error control coding system to get a hard determination output or is sent to a determiner in an error control coding system to get a soft determination output that is finally sent to a coder. The method promotes the transmission rate and the anti-interference ability and advances the spectrum efficiency.

Space domain filter detecting method in a multi-antenna wireless communication system

A detection method of space domain maximum posteriori probability (MAP) in a wireless communication system is a kind of detection technique of space domain MAP in a multi-aerial wireless communication system, which makes the detection of iteration soft interference elimination for the interference signals in the other moments, and makes the MAP detection or the simplified MAP detection for the all signals in current time and space domain. It includes the steps of: taking a fading block as a unit; the received signals are matched and combined in time domain and space domain, and calculating an equivalent channel matrix; making the sequence detection, calculating estimation and variance of the signals before the ending of detecting internal iteration; when the internal iteration detection finishes, the result is outputted, or is outputted after hard decision.

Detection method of space domain maximum posteriori probability in a wireless communication system

The present invention relates to a method and an apparatus for adjusting an average interval of channel estimation dynamically based on Doppler-shift. The method comprises the steps of estimating Doppler-shift by using level cross rate (LCR) according to differently moving speeds of mobile terminals, determining the optimal average interval of channel estimation based on the relationship between the existing Doppler-shift and the optimal average interval of channel estimation, dynamically adjusting the average interval of channel estimation according to the determined the optimal average interval of channel estimation to make the coherent receiver obtain the optimal estimation performance at different moving speeds. The apparatus of the present invention comprises a channel estimation module, a valid/strongest finger selection module, a RAKE demodulation and combining module, a RAKE output decision module, an LCR detection and Doppler-shift estimation module, a Gaussian noise power estimation module, a strongest path signal power estimation module, and an optimal average interval calculation module.

Method and equipment for regulating dynamically an average area of a channel estimation

The present invention discloses a method for pilot channel tracking based on multipath channel barycenter tracking loop, comprises steps of evaluating multipath fading channel parameters, calculating the barycenter of a multipath energy window, and loop filtering and adjusting the phase of spread spectrum sequence codes. The method of the invention does not need to individually track each delay path, thereby improving the tracking performance and timing recovery stability of a spread spectrum receiver. Only a multipath channel evaluator and a multipath energy window barycenter calculating means are used to track PN signals from a plurality of signal sources, thereby reducing hardware. Thus, a novelty coherent spread spectrum receiver can be constituted by cooperating with other parts.

Pilot channel tracking method based on multipath barycenter tracking loop

The present invention discloses an apparatus for initial synchronization and cell search in a CDMA system based on multipath energy window. The apparatus perform initial synchronization and adjacent cell search by using multipath energy window based on the processing method of multipath energy window. The apparatus can be implemented based on a parallel correlator bank. This invention also provides the application of the apparatus to a coherent spreading receiver.

Means for initiative synchronization and cell searching based on the CDMA system of multipath energy window

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Nanjing, China

Xiaohu You