Abstract: The invention relates to a method for operating a secondary station in a communication network including a primary station, the method comprising generating a precoding matrix obtained from the Hadamard product of an alphabet modifying matrix and an original precoding matrix, wherein the original precoding matrix consist of complex coefficients of equal magnitude, transmitting a precoding report representative of the precoding matrix to the primary station.

Abstract: A bi-directional interface circuit includes a transmitter portion, a receiver portion, a current source bias circuit, and a switch. When the interface circuit is transmitting data, the switch steers the bias current generated by the current source bias circuit to the transmitter portion of the interface. When the interface is receiving data, the switch steers the bias current to the receiver portion of the interface. Thus, the current-source bias circuit is kept on regardless of whether the interface is transmitting or receiving data. Because the current-source bias circuit is not turned on and off, the switching noise generated when the interface transitions between transmitting and receiving operations is eliminated or reduced. Consequently, any dead time inserted for such a transition can be minimized, and the effective bandwidth of the interface is increased.

Abstract: A method, device and system for complex carrier modulation are provided in the disclosure, wherein e?i?t or ei?t is used as a carrier frequency to perform carrier modulation on a to-be-carried signal. The modulated signal transmitted in a medium is a rotating complex signal. The method can enable right and left frequency bands to carry independent information. Therefore the spectrum utility ratio is improved. Employing the method for complex carrier modulation provided in the disclosure can use the right and left frequency spectrum resources adequately, and the loss of signal energy is small, therefore the capacity of a channel is improved greatly.

Abstract: The method includes providing a stream of data to be transmitted, and processing the data by means of channel coding with a time-varying code rate, thereby generating a stream of channel coded data. The method further includes forming succeeding transmission time intervals and distributing the channel coded data on the transmission time intervals, and adjusting a transmission power of the signal to be transmitted by timely positioning a transmission power slope between two succeeding transmission time intervals so that the transmission power slope is contained completely within one transmission time interval of the two transmission time intervals, wherein the one transmission time interval comprises a lower nominal code rate or a lower nominal transmission power than the other one of the two transmission time intervals.

Abstract: A method of controlling a power spectrum of a navigation transmission signal in a navigation system is provided. The navigation transmission signal comprising a carrier signal, a navigation ranging signal, a data signal, and at least one subcarrier modulation signal. The method comprising modulating the navigation ranging signal with the at least one subcarrier modulation signal, wherein the at least one subcarrier modulation signal comprises a number, m, of amplitude levels, where m>2, to produce a modulated ranging signal. The amplitude levels having respective magnitudes and durations arranged to influence the power spectrum of the navigation signal in a predetermined manner. Modulating the carrier with the modulated ranging signal and the data signal to generate the navigation signal.

Abstract: According to an aspect of the present invention, a method of transmitting service data may include encoding service data, mapping the encoded service data, MIMO encoding the mapped data using a MIMO matrix, time-interleaving the MIMO encoded data, building a signal frame including and signaling data and the time-interleaved data, frequency interleaving the time-interleaved data in frequency domain, modulating the signal frame including the frequency-interleaved data by OFDM (Orthogonal Frequency Division Multiplex) scheme and transmitting the modulated signal frame.

Abstract: Provided are a transmitter, a receiver and methods of padding and depadding zero bits to an L1-post signaling. The transmitter includes: a zero padder configured to divide an information word into a plurality of groups, pad zero bits to at least one of the plurality of groups by group unit, and pad additional zero bits to at least one of the plurality of groups remaining after the zero bits are padded, thereby constituting the information word for encoding the L1-post signaling; and an encoder configured to perform encoding on the information word for encoding the L1-post signaling, wherein the zero padder pads the additional zero bits according to a predetermined criterion, starting from a front end or a back end of the at least one of the remaining groups.

Abstract: A multi-carrier communication system such as an OFDM or DMT system has nodes which are allowed to dynamically change their receive and transmit symbol rates, and the number of carriers within their signals. Changing of the symbol rate is done by changing the clocking frequency of the nodes' iFFT and FFT processors, as well as their serializers and deserializers. The nodes have several ways of dynamically changing the number of earners used. The selection of symbol rate and number of earners can be optimized for a given channel based on explicit channel measurements, a priori knowledge of the channel, or past experience. Provision is made for accommodating legacy nodes that may have constraints in symbol rate or the number of carriers they can support.

Abstract: A method and apparatus for transmitting an orthogonal frequency division multiplexing (OFDM) signal including converting a distribution of a signal in which inverse Fourier transform is performed in an OFDM system and a method of receiving an OFDM signal including expanding a received signal are provided, and by changing a magnitude distribution of a signal that is output from an OFDM modulator to a bimodal Gaussian distribution, an influence of noise in a receiving terminal can be reduced, and by limiting a signal that is output from an OFDM modulator to an appropriate magnitude, a phase in the receiving terminal can be prevented being wrongly demodulated.

Abstract: A receive node device includes a processor coupled to a memory. The processor is configured to report a first sub-index and to report at least one additional second sub-index for each one of one or more matrices. Each one of the one or more matrices is indexed by the first sub-index and the second sub-index. The first sub-index and the second sub-index have different time-frequency reporting granularity.

Abstract: In a process variable transmitter, a sensor signal is sampled, using a clock signal, at a sensor sampling frequency. Interference is also sampled at the sensor sampling frequency. A comparison is made to determine whether the interference at the sensor sampling frequency or harmonics of the sensor sampling frequency exceed a threshold level. If so, the clock signal is changed to adjust the sensor sampling frequency away from the frequency of the interference.

Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus receives a first message from a first wireless communication device and a second message from a second wireless communication device, obtains information associated with a first processing delay with respect to the first message and a second processing delay with respect to the second message, and transmits a third message comprising an indication of the information associated with the first and second processing delays.

Abstract: Successive pairs of OFDM symbols are transmitted by an OFDM transmitter and received by an OFDM receiver. The successive pairs include a first pair of OFDM symbols. First and second OFDM symbols of the first pair both include pilot symbols on two subcarriers that are symmetric about a center carrier frequency. The two subcarriers are the same for the first and second OFDM symbols. The pilot symbols on the two subcarriers for the first and second OFDM symbols compose an orthogonal matrix. The OFDM receiver estimates frequency responses at frequencies including the frequencies of the two subcarriers and compensates for signal impairment based at least in part on the estimated frequency responses.

Abstract: Various embodiments provide for systems and methods for wireless communications that implement transmitter protection schemes using spatial combining. The protection scheme implemented by some embodiments provides for a number of benefits, including without limitation: hitless protection; constant power monitoring for each wireless channel being utilized; extra gain to wireless signals transmitted; beam steering, beam hopping, and beam alignment capabilities; and varying levels of transmission path protection (e.g., 1+1 protection, or 1+N protection). Additionally, the features of some embodiments may be applied to a variety of wireless communications systems including, for example, microwave wireless systems, cellular phone systems and WiFi systems.

Abstract: A transmitting apparatus is provided for transmitting signals in a multi carrier system, in which pilot signals and data mapped on frequency carriers are transmitted in a transmission bandwidth, wherein a part of the transmission bandwidth is not used to transmit signals. The apparatus includes a pilot signal mapper for mapping pilot signals onto selected frequency carriers according to a pilot pattern that is adapted for a channel estimation in a corresponding receiving apparatus, the pilot pattern enabling a channel estimation for frequency carriers next to the part of the transmission bandwidth that is not used to transmit signals.

Abstract: In a method of transmitting a data stream from a transmitter in a multiple-input-multiple-output (MIMO) wireless communication system, where the transmitter comprises a plurality of transmit antennas, a discrete Fourier transform (DFT) is applied to the data stream to generate a plurality of symbol sequences; symbols of a first symbol sequence from the plurality of symbol sequences are paired with symbols of a second symbol sequence from the plurality of symbol sequences to generate a plurality of symbol pairs, wherein the pairing results in an orphan symbol; a space-time block code (STBC) is applied to the symbol pairs to generate a plurality of sets of STBC symbols, each set of STBC symbols being associated with a corresponding one of the plurality of antennas; a cyclic delay diversity (CDD) operation is applied to the orphan symbol to generate a plurality of CDD symbols, each CDD symbol being associated with a corresponding one of the plurality of antennas; and each one of the antennas transmits the corres

Abstract: A method for optimising a coded modulation scheme with a given spectral efficiency for communication over a fading channel represented/identified by B fading gains, where B is an integer number expressing the ratio between a code word duration and the duration over which the fading remains constant. The fading gains belong to a B-dimensional space of fading gains.

Abstract: In one aspect, a method for mitigating an effect of an interfering radio signal at a multiple antenna receiver includes forming an estimate of a relationship of the interfering signal among signals received from the multiple antennas. In general, the interfering signal does not share the same communication technology as a desired signal. The signals received from the multiple antennas filtered and combined according to the estimate of the relationship of the interfering channels to reduce an effect of the interfering signal. Desired data present in the desired signal represented in the filtered and combined signals is decoded and the estimate of the relationship of the interfering signals is updated according to the decoding of the desired signal.

Abstract: A cognitive radio communication system using a multiple input multiple output (MIMO) communication technology is provided. A cognitive radio base station includes a plurality of antennas, a group setting unit to set at least one sensing terminal group that includes at least one sensing terminal among a plurality of terminals, and a signal generator to generate a transmission signal to transmit the transmission signal using channels formed between the plurality antennas and the plurality of terminals, so that the at least one sensing terminal is accorded a sensing time.

Abstract: In a device or system, a total tone count is determined or selected for modulating a data payload. Two or more code words are interleaved into the data payload, and the data payload is transmitted on a channel of the device or system.

Abstract: Systems and methods for establishing transmission format parameters between communication devices are provided. In some aspects, a method includes identifying, by a first base station, a first communication session with a first user equipment. A master set of transmission format parameters is shared between the first base station and the first user equipment. The method also includes assigning a first subset of the master set of transmission format parameters to the first communication session. The first subset is specifically assigned to the first communication session and specifies which of the master set of transmission format parameters is allocated for use in the first communication session. The method also includes transmitting an indicator of the first subset to the first user equipment.

Abstract: An apparatus and a method for operating a memory compensation Digital Pre-Distortion (DPD) are provided. In the method for operating a memory compensation DPD system, an input signal is received. An input average power of the input signal is determined. When the input average power of the input signal belongs to a non-linear section of the input average power, DPD is performed on a previous signal corresponding to a memory degree set depending on at least one non-linear section of the input average power.

Abstract: Wireless communication wherein channel estimation accuracy is improved while keeping the position of each bit in a frame, even when a modulation system having a large modulation multiple value is used for a data symbol. An encoding operation encodes and outputs transmitting data (bit string) and a bit converting operation converts at least one bit of a plurality of bits constituting a data symbol to be used for channel estimation, among the encoded bit strings, into or ‘0’ or ‘0’. A modulating operation modulates the bit string inputted from the bit converting operation by using a single modulation mapper and a plurality of data symbols are generated.

Abstract: A binary allocation in a hierarchical coding/decoding comprising a coding/decoding of a digital signal enhancement layer. The signal comprises a succession of L samples, each sample being represented by a mantissa and an exponent. The method comprises the allocation of a predetermined number Nb of enhancement bits to a part at least of the L samples of highest exponent values. In particular, the method comprises the steps: a) enumerating the exponents of the L samples each having a given value, b) calculating at least one aggregate of enumerations of exponents by decreasing values of exponent until the predetermined number Nb is approximated from above, for c) determining a threshold value of largest exponent iexp0 of sample for which no more enhancement bit is available, and allocating the Nb enhancement bits, according to chosen rules, to the samples whose exponent is greater than the aforesaid threshold value iexpo.

Abstract: This invention is for a method for transforming a seismic trace into a compressed domain. The seismic source wavelet is transformed into a zero degree phase wavelet and a shifted 90 degree phase wavelet, and the two wavelets span a 2-dimensional sub-space. A dictionary is created by collecting the wavelets in the sub-space. In practice this dictionary is usually combined with conventional existing wavelet dictionaries. The seismic trace is projected onto the dictionary (sub-space alone or combined) to find the best matching projection, with a residual determined after each projection, wherein the sum of the residuals determines the fidelity of the data compression.

Abstract: An apparatus comprising a digital subscriber line (DSL) transmitter configured to transmit a discrete multi-tone (DMT) superframe comprising a sync frame and a data frame, wherein a time duration of the superframe is equal to at least a sum of a time duration of the sync frame and twice a time duration of the data frame, and turn off at least a portion of the DSL transmitter for a portion of the time duration of the superframe, wherein the portion of the time duration is no shorter than the duration of the data frame.

Abstract: A method of processing data of an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a transmitter and a receiver processing the OFDM symbol are provided. The method performed by the transmitter includes: mapping first data and second data to an OFDM symbol and transmitting a frame including the OFDM symbol. The mapping includes additionally mapping at least a portion of the second data to cells of the OFDM symbol which remain after the first data and the second data are mapped to the OFDM symbol.

Abstract: A receiver of a signal frame such as T2 frame used in a DVB-T2 system is provided. The receiver includes: a receiving unit configured to receive a frame including a preamble symbol in which a pseudo random noise (PN) sequence is inserted; a PN sequence detector configured to detect the PN sequence from the received frame; a controller configured to measure a start point of the preamble symbol and frequency offset of the PN sequence inserted in the preamble symbol, based on the detected PN sequence; and a preamble symbol detector configured to detect the preamble symbol according to the measured start point of the preamble symbol and the measured frequency offset of the PN sequence. Therefore, the receiver accurately measures the start point of the preamble symbol and the frequency offset and estimates a channel based on the PN sequence inserted in the preamble symbol.

Abstract: A transmitter includes a frame generator which generates a plurality of frames each of which includes a preamble symbol and a data symbol, a pilot inserter which inserts a plurality of first pilots in the preamble symbol according to a predetermined first arrangement pattern and inserts a plurality of second pilots in a data symbol according to a second arrangement pattern, and a transmitting unit which transmits the plurality of frames in which the first and second pilots are inserted. Accordingly, a memory needed to store pilots may be reduced and precise synchronization may be performed based on an extended number of pilots.

Abstract: A method for transmitting and receiving a signal and an apparatus for transmitting and receiving a signal are disclosed. The method for receiving the signal includes receiving (S210) the signal in a first frequency band, identifying (S220) a first pilot signal including, a cyclic prefix obtained by frequency-shifting a first portion of an useful portion of the first pilot signal and a cyclic suffix obtained by frequency-shifting a second portion of the useful portion of the first pilot signal from the received signal, demodulating (S220) a signal frame including a physical layer pipe (PLP) to which a service stream is converted, by an orthogonal frequency division multiplexing (OFDM) scheme, using information set in the first pilot signal, parsing (S230) the signal frame and obtaining the PLP and obtaining (S240) the service stream from the PLP.

Abstract: A method operates to transmit a data signal by a transmission unit of a wireless multiple-input/multiple-output (MIMO) communication system. The communication system includes the transmission unit and a reception unit, the transmission unit having a plurality of transmission antennas and the reception unit having a plurality of reception antennas. The method includes performing a first transmission of a data signal, the first transmission including transmitting the data signal by each one of the plurality of transmission antennas, and performing a second transmission of the data signal at a time later than the first transmission, the second transmission including transmitting at least one spectrally modified signal variant of the data signal by at least one antenna of the plurality of transmission antennas.

Abstract: In an method for generating a data unit for transmission via a communication channel, a data portion of the data unit is generated. Orthogonal frequency division multiplexing (OFDM) symbols of the data portion are generated using one of (i) a normal guard interval, (ii) a short guard interval and (iii) a long guard interval. A preamble of the data unit is generated. The preamble indicates whether at least OFDM symbols of the data portion are generated using the normal guard interval, the short guard interval, or the long guard interval. The data unit is then generated to include the preamble and the data portion.

Abstract: An apparatus and method reduce power consumption in a broadband wireless communication system. A transmitting end apparatus that includes a plurality of transmit (Tx) antennas includes a control block, a Processor (DSP) block, a modem block, and at least one power controller. The control block determines a traffic amount based on an amount of used resources. The Digital Signal Processor (DSP) block performs scheduling by using a subset of Tx antennas and a subset of resources on a frequency axis if the traffic amount is less than a threshold. The modem block applies boosting to a signal transmitted using the subset of resources. And at least one controller turns off an operation of at least one power amplifier that corresponds to at least one Tx antenna that is not included in the subset of Tx antennas.

Abstract: A transmitting apparatus, a receiving apparatus and a method of controlling these apparatus are provided. The transmitting apparatus includes: a frame generator configured to generate a plurality of frames which include one or more kinds of data; a preamble symbol inserter configured to insert at least one preamble symbol in each of the plurality of frames, and insert, in a preamble symbol of a frame, location information about at least one frame, among the plurality of frames, which includes a same kind of data as a kind of data included in the frame; and a transmitter configured to transmit the plurality of frames in each of which the preamble symbol is inserted.

Abstract: The system and method of the present disclosure exploit the fact that an undesired phase offset between signals up-converted and transmitted by transmitters of at least two transceivers is correlative with a phase offset between signals received and down-converted by receivers of the at least two transceivers. Such correlation occurs when the transmitter and receiver in each of the at least two transceivers share the same local oscillator and thus experience the same or very similar random phase noise. Using this fact, the system and method of the present disclosure are configured to measure the phase offset between signals received and down-converted by the receivers of the at least two transceivers and then use the measured phase offset to compensate for the phase offset between the signals up-converted by the transmitters of the at least two transceivers. This compensation allows MIMO communication, such as spatial multiplexing, to be better performed.

Abstract: According to one embodiment, an adjacent-channel interference reject filter comprises a short-pulse inverter which includes a short-pulse sensor configured to detect a pulse in an intermediate frequency signal supplied to the device. The short-pulse sensor detects pulses having a pulse width less than or equal to some predetermined width. The short-pulse inverter also includes a pulse inverter configured to invert the pulse detected by the short-pulse sensor. The adjacent-channel interference reject filter may also include an inversion controller to control the inverting of detected short pulses. An adjacent-channel interference reject filter may be included in various devices such as wireless communication devices.

Abstract: Methods and apparatus are provided for transmitting/receiving data in consideration of carrier frequency in the mobile communication system using multiple transmission antennas for increasing data rate and system throughput. A number of antennas and a plurality of symbols are determined via an in-phase domain and a quadrature-phase domain. The symbols are mapped according to the number of antennas and the in-phase domain and the quadrature-phase domain. The mapped symbols are transmitted through corresponding antennas.

Abstract: In one aspect, a method includes performing a mapping on bits to form a complex data symbol, applying a frequency rotation mask to the complex data symbol based on a polynomial phase, performing an inverse discrete Fourier transform (IDFT) after applying the frequency rotation mask, applying a time domain window after performing the IDFT, converting digital data to analog data after applying the time window and transmitting the analog data as an analog signal.

Abstract: A wireless communication apparatus and a wireless communication method wherein even when the permissible delay amount of data is small, the permissible delay thereof can be satisfied. A data type determining part determines whether the delay of transport data or control information should be allowed or not. A pilot signal insertion control part decides, based on pilot insertion interval information and allowable delay information, that a pilot signal is placed adjacently to data that is not allowed to delay. A multiplexing part multiplexes encoded and modulated transport data with the pilot signal generated by a pilot signal generating part in such a manner that realizes the placement decided by the pilot signal insertion control part.

Abstract: A precoding weight generation method involves generating a channel matrix having channel state information transmitted as feedback from mobile stations undergoing spatial multiplexing for each cell that base stations manage, and generating precoding weights. When data transmission is targeted for a first mobile station that transmits the channel state information as feedback as well as transmits the channel state information to a weight generation target cell that is a target for generation of precoding weights, precoding weights are generated so as not to suppress interference on a second mobile station that transmits the channel state information as feedback as well as transmits the channel state information to the weight generation target cell, while suppressing interference on a third mobile station that does not transmit the channel state information as feedback except to the weight generation target cell.

Abstract: Techniques for controlling a power spectrum of a navigation transmission signal in a navigation system are disclosed. In one particular embodiment, the techniques may be realized as a method of controlling a power spectrum of a navigation transmission signal in a navigation system, the navigation transmission signal comprising a carrier signal, a ranging code, a data signal, and at least one stepped subcarrier modulation signal. The method may comprise modulating the canier signal by the at least one stepped subcarrier modulation signal, the data signal, and the ranging code to generate the navigation transmission ranging signal, wherein the at least one stepped subcarrier modulation signal may comprise a number, m, of amplitude levels, where m>2. The amplitude levels may be arranged to constrain the power spectrum of the navigation transmission signal in a predetermined manner.

Abstract: An amplification system and an integrated circuit include a bandpass filter and an amplifier. The bandpass filter filters an input digital bitstream or an amplified signal to provide a filtered signal. The bandpass filter exhibits constant input impedance over a passband associated with the input digital bitstream, and a stopband associated with shaped-noise energy, thereby increasing signal-to-noise ratio and/or signal-to-distortion ratio associated with the filtered signal. The amplifier amplifies at least one of the filtered signal and the input digital bitstream to provide the amplified signal. A method of providing amplification includes bandpass filtering an input digital bitstream or an amplified signal to provide a filtered signal, providing constant input impedance over a passband and a stopband by the bandpass filtering, and amplifying at least one of the filtered signal and the input digital bitstream to provide the amplified signal.

Abstract: A system and method for generating a low probability of detection (LPD) waveform is presented. The method modulates pre-modulated symbols using pulse-position modulation (PPM) to produce PPM modulated signals with a modulated in-phase (I) component and a modulated quadrature (Q) component. Next, frequency hopping is used to transmit the modulated I component at a randomized start time within a time slot and to transmit the modulated Q component at the randomized start time within the same slot. The modulated Q component does not overlap with the modulated I component. The method can also overlay transmission security (TRANSEC) pseudorandom (PN) overlay on the modulated Q component and the modulated I component before the modulated Q component and the modulated I component are transmitted.

Abstract: A phase shift keying transmitter circuit that includes: a variable frequency conversion stage adapted to receive a first data signal, wherein the variable frequency conversion stage comprises a plurality of frequency modulating elements, wherein the first data signal controls the number of the plurality of frequency modulating elements that are operated so as to control an operating frequency of the variable frequency conversion stage; and an output stage configured to switch between one of two possible outputs, the signals provided by one of the two possible outputs having an opposite polarity to the other, wherein the output stage is configured to receive a second data signal to control the switching between the two possible outputs, wherein the output stage is coupled to the variable frequency conversion stage and wherein the switching between the two possible outputs changes the phase of a signal from the variable frequency conversion stage by 180°.

Abstract: A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals comprises an encoder for encoding service data corresponding to each of a plurality of transmission unit, wherein the each of a plurality of transmission unit carries at least one service component, a frame builder for building at least one signal frame including the encoded service data, a phase distortion unit for performing a phase distortion on data in the built at least one signal frame, a modulator for modulating data in the built at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme and a transmitter for transmitting the broadcast signals including the modulated data.

Abstract: Systems that allow for DFE functionality to be eliminated from the receiver side of a communication system and for a DFE-like functionality to be implemented instead at the transmitter side of the communication system are provided. By removing the DFE functionality from the receiver side, error propagation can be eliminated at the receiver and receiver complexity can be reduced drastically. At the transmitter side, the DFE-like functionality provides the same DFE benefits, and with the transmitter environment being noise-free, no errors can occur due noise boosting, for example. The DFE-like functionality at the transmitter side can be implemented using non-linear (recursive or feed-forward) pre-coders or a combination of non-linear pre-coders and linear filters, which can be configured to invert a net communication channel between the transmitter and the receiver. Embodiments particularly suitable for fiber optic channels and server backplane channels are also provided.

Abstract: A transmitting apparatus, a receiving apparatus and methods of transmission and reception are provided. The transmitting apparatus includes: a frame generator configured to map data contained in an input stream to at least one signal processing path to generate a frame; an information inserter configured to insert signaling information in a signaling region of the frame; and a transmitter configured to transmit the frame in which the signaling information is inserted, wherein the signaling information comprises information on an input type of each of the at least one input stream and information on a type of data which is mapped to the at least one signal processing path.

Abstract: A coordinate transmitter, a coordinate receiver and a coordinate transceiver are provided. The coordinate transmitter includes a global positioning system (GPS) module, a processing unit and a communication module. The global positioning system module receives a global positioning system signal set. The processing unit captures a coordinate data string from the GPS signal set. The processing unit replaces at least one English letter data and at least one punctuation mark data in the coordinate data string. The processing unit converts the replaced coordinate data string into a dual tone multi frequency (DTMF) signal set. The communication module transmits the DTMF signal set.

Abstract: A transmitter includes first generator to generate pilot source signal by modulating pilot sequence, second generator to generate data source signal with time length longer than that of pilot source signal by modulating data sequence, first cyclic shifter to perform cyclic shift of first shift amount to pilot source signal to generate first pilot signal, second cyclic shifter to performs cyclic shift of second shift amount to data source signal to generate first data signal, third cyclic shifter to perform cyclic shift of third shift amount to pilot source signal to generate second pilot signal, fourth cyclic shifter to perform cyclic shift of fourth shift amount to data source signal to generate second data signal, first transmit antenna to transmit first pilot signal and first data signal, and second transmit antenna to transmit second pilot signal and second data signal.

Abstract: A method for generating a codebook and a method and an apparatus for data transmission are provided. The method includes: receiving a label of a codeword sent by a User Equipment (UE); selecting the codeword identified by the label from the codebook for eight-antenna; and coding data to be sent by using the codeword. The codebook for eight-antenna includes at least one rank-8 codeword for eight-antenna. The rank-8 codeword for eight-antenna is generated by multiplying an inverse matrix of a rotation matrix for eight-antenna with an eight-dimensional matrix formed by rank-4 codewords for four-antenna; or generated by extending rank-4 codewords for eight-antenna, where the rank-4 codeword for eight-antenna is generated according to codewords for four-antenna. Therefore, the codeword in the codebook for eight-antenna is applicable to scenarios including dual-polarization strong correlation, dual-polarization weak correlation, single-polarization strong correlation, and single-polarization weak correlation, etc.