Abstract: Provided is an improved beam control method of an array antenna based on frequency diversity. The method includes: signals from a transmitter are received by a receiving array which includes a first sub-array and a second sub-array, wherein the first sub-array includes M uniformly arranged array elements, the second sub-array includes N uniformly arranged array elements, M and N are coprime integers, and N?0; a signal received by each array element in the receiving array is input into a constructed model, and a covariance matrix is output after processing the signal via the model; a virtual array is constructed at a receiver, wherein a virtual array element in the virtual array is a second-order statistic calculated according to the covariance matrix; and a frequency is randomly selected for each virtual array element from a frequency set of the virtual array, so as to form a beam pattern.

Abstract: The present disclosure relates to a method for coding on a time-space two-dimensional channels, in which the data bits to be transmitted are coded from the time-domain and the space-domain, respectively, to form time-space two-dimensional coding. the proposed coding operation in the space-domain and the time-domain can adopt different coding structures, coding rates and modulation constellations; subsequently, the system expresses each 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; next, the sending terminal selects the coding structure according to the code words of the time-domain, and encodes each data stream according to time-domain coding rates, and eventually forms data blocks of an equal length in the time-domain through the rate matching.

Abstract: 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.

Abstract: 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.

Abstract: This application provides a communication method and device. The 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. In this way, a device with wideband reception performance and a device with narrowband reception performance can be supported.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 iterat

Abstract: 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

Abstract: 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 frequenc

Abstract: 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.

Abstract: 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.

Abstract: 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 iterat

Abstract: 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.

Abstract: 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 and a same direction impulse sequence, the front is the positive and negative impulse sequence, which includes odd impulses with alternant positive and negative polarities; the rear is the same direction impulse sequence, which is composed of impulses with same polarity, and the polarity of impulse in the same direction impulse sequence is same as the polarity of the last impulse in the positive and negative impulse sequence.

Abstract: 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.

Abstract: 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 frequenc

Abstract: A space division multiple access transmission method of a statistical characteristic mode is provided by the present invention.

Abstract: 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.