A device includes circuitry configured to spread one or more symbols with one or more orthogonal codes into spread signals having a predetermined number of bits. The amplitude of the spread signals is modified via one or more layer coefficients and the spread signals are multiplexed into a layered transmit signal.

In some embodiments of the invention, OFDM symbols are transmitted as a plurality of clusters. A cluster includes a plurality of OFDM sub-carriers in frequency, over a plurality of OFDM symbol durations in time. Each cluster includes data as well as pilot information as a reference signal for channel estimation. In some embodiments, a plurality of clusters collectively occupy the available sub-carrier set in the frequency domain that is used for transmission. In some embodiments of the invention data and/or pilots are spread within each cluster using code division multiplexing (CDM). In some embodiments pilots and data are separated by distributing data on a particular number of the plurality of OFDM symbol durations and pilots on a remainder of the OFDM symbol durations. CDM spreading can be performed in time and/or frequency directions.

A precoding method in a multi-antenna system includes the following steps. A reference device transmits a first reference signal to base station antennas. A base station calculates uplink channel information and transmits it to a coordination server. The base station transmits a second reference signal to the reference device. The reference device calculates downlink channel information and transmits it to the coordination server. The coordination server performs the following steps: calculate carrier frequency offsets (CFO) between base stations according to the uplink channel information; calculate channel calibration coefficients according to the CFO, the uplink channel information, and the downlink channel information; calculate a first downlink channel at a first time point according to a user equipment's first uplink channel and the channel calibration coefficients; use a prediction function to predict a second downlink channel at a second time point; generate a precoder according to the second downlink channel.

Provided is a high speed phase shift keying modulator. The high speed phase shift keying modulator has variable pipeline buffers formed at an input side and an output side of a bandlimiting filter and a compensation filter to ensure timing margins of the bandlimiting filter and the compensation filter, so that a ultra-high speed phase shift keying modulator is provided.

Embodiments of the present application disclose a spreading method, a spreading control method, and apparatuses thereof. The spreading method comprises: determining a first combined spreading code to be used at least according to first information associated with spreading by using combined spreading codes, the first combined spreading code comprising N spreading codes, and N being an integer not less than 2; and spreading N data units by using the first combined spreading code, wherein the N data units comprise at least one first unit and at least one second unit, the at least one first unit comprises data to be sent, and the at least one second unit is configured to recover the at least one first unit. The methods and apparatuses of the embodiments of the present application can effectively solve the problem of insufficient number of orthogonal spreading codes by using combined spreading codes.

Certain aspects of the present disclosure relate to methods and apparatus for phase noise estimation in data symbols for millimeter wave (mmW). A method for wireless communications by a transmitting device is provided. The method generally includes identifying a phase noise metric associated with at least one receiving device; determining a phase noise pilot configuration based, at least in part, on the identified phase noise metric; and providing an indication of the phase noise pilot configuration to the at least one receiving device. A receiving device can receive the phase noise pilots in accordance with the configuration and determine phase noise for a data symbol based on the received phase noise pilots.

Methods, devices, and systems for the transmission of information in a wireless communication system are disclosed. In one embodiment, a method for the transmission of information in a wireless communication system comprises receiving a downlink message, wherein the downlink message includes a first control channel element; determining a first index using the location of the first control channel element; determining a second index; determining a first orthogonal resource using the first index; determining a second orthogonal resource using the second index; spreading an uplink message using the first orthogonal resource to form a first spread signal; spreading the uplink message using a second orthogonal resource to form a second spread signal; transmitting the first spread signal using a first antenna; and transmitting the second spread signal using a second antenna.

Data is scrambled at a transmitter according to one of a number of predetermined scrambling sequences which are associated with a particular one of a number of predetermined transmit antenna diversity schemes (i.e., a specific number of transmit antenna ports). Received data is decoded using one or more of the known transmit antenna diversity schemes and the scrambled data is descrambled according to a corresponding descrambling sequence (related to the scrambling sequence). Based on the descrambled data, the receiver determines which transmit antenna diversity scheme (i.e., the number of antenna ports) is used by the transmitter. In one specific embodiment, CRC parity data is scrambled in the transmitter and the receiver descrambles the recovered CRC parity data according to a descrambling sequence, computes CRC parity data from the received data, and compares the descrambled CRC parity data to the newly computed CRC parity data.

In some embodiments of the invention, OFDM symbols are transmitted as a plurality of clusters. A cluster includes a plurality of OFDM sub-carriers in frequency, over a plurality of OFDM symbol durations in time. Each cluster includes data as well as pilot information as a reference signal for channel estimation. In some embodiments, a plurality of clusters collectively occupy the available sub-carrier set in the frequency domain that is used for transmission. In some embodiments of the invention data and/or pilots are spread within each cluster using code division multiplexing (CDM). In some embodiments pilots and data are separated by distributing data on a particular number of the plurality of OFDM symbol durations and pilots on a remainder of the OFDM symbol durations. CDM spreading can be performed in time and/or frequency directions.

Embodiments of the present application disclose a spreading method, a spreading control method, and apparatuses thereof. The spreading method comprises: determining a first combined spreading code to be used at least according to first information associated with spreading by using combined spreading codes, the first combined spreading code comprising N spreading codes, and N being an integer not less than 2; and spreading N data units by using the first combined spreading code, wherein the N data units comprise at least one first unit and at least one second unit, the at least one first unit comprises data to be sent, and the at least one second unit is configured to recover the at least one first unit. The methods and apparatuses of the embodiments of the present application can effectively solve the problem of an insufficient number of orthogonal spreading codes by using combined spreading codes.