A receiver circuit for separating a plurality of layers multiplexed in an orthogonal frequency domain multiplexed (OFDM) signal includes: a descrambling sub-circuit configured to descramble a plurality of signals received on non-adjacent subcarriers of the OFDM signal to generate a plurality of descrambled signals; an inverse fast Fourier transform sub-circuit configured to transform the descrambled signals from a frequency domain to a received signal including a plurality of samples in a time domain; and a layer separation sub-circuit configured to separate the layers multiplexed in the received signal by: defining a first time domain sampling window and a second time domain sampling window in accordance with a size of the inverse fast Fourier transform; extracting one or more first layers from the samples in the first time domain sampling window; and extracting one or more second layers from the samples in the second time domain sampling window.

A method of a terminal in a wireless communication system is disclosed. The method includes identifying demodulation reference signal (DMRS) type information and DMRS symbol length information, identifying port number information for receiving a DMRS and receiving the DMRS based on the DMRS type information, the DMRS symbol length information and port number information, wherein the port number information indicates a port number for the terminal in DMRS information including parameters for code division multiplexing (CDM) group information, offset information, frequency-domain orthogonal cover code (OCC) information, and time-domain OCC information corresponding respectively to multiple port numbers, and wherein the DMRS information is defined per DMRS type.

It is possible to provide a radio communication terminal device and a radio transmission method which can improve reception performance of a CQI and a reference signal. A phase table storage unit stores a phase table which correlates the amount of cyclic shift to complex coefficients {w1, w2} to be multiplied on the reference signal. A complex coefficient multiplication unit reads out a complex coefficient corresponding to the amount of cyclic shift indicated by resource allocation information, from the phase table storage unit and multiplies the read-out complex coefficient on the reference signal so as to change the phase relationship between the reference signals in a slot.

An OFDM transmitter spreads original data symbols with a complex-valued spreading matrix derived from a discrete Fourier transform. Spread data symbols are mapped to OFDM subcarriers. Spreading and mapping are configured to produce a transmitted spread-OFDM signal with a low peak-to-average power ratio (PAPR) and orthogonal code spaces. In MIMO systems, the complex-valued spreading matrix can comprise a MIMO precoding matrix, and the code spaces can comprise MIMO subspaces. In Cooperative-MIMO, a combination of low code-space cross correlation and low PAPR can be achieved.

A transmission device includes a first mapper, a second mapper, a converter, a superposer, and a transmitter. The first mapper is configured to map a first bit stream of a first data series to generate a first modulated symbol stream. The second mapper is configured to map a second bit stream of a second data series to generate a second modulated symbol stream. The first modulated symbol stream and the second modulated symbol stream are representable on a complex plane extending in a first direction and a second direction. The converter is configured to convert the second modulated symbol stream in accordance with the first modulated symbol stream only in the first direction on the complex plane. The superposer is configured to superpose the first modulated symbol stream and the second modulated symbol stream converted by the converter, at an amplitude ratio, to generate a multiplexed signal.

Methods and apparatuses are disclosed regarding a wireless field unit, which may receive a plurality of forward link assignment messages for a plurality of time slots for a plurality of forward link transmissions, each message including an indication of a modulation and a code rate associated with a respective forward link transmission. The field unit may receive at least one of the forward link transmissions in at least one time slot at the respective indicated modulation and code rate. The field unit may receive a plurality of reverse link assignment messages for a plurality of time slots for a plurality of reverse link transmissions, each message including an indication of a modulation and a code rate associated with a respective reverse link transmission. The field unit may transmit at least one of the reverse link transmissions in at least one time slot at the respective indicated modulation and code rate.

A transmitter includes: a first transmission block that generates a first radio wave having an information signal modulated thereon and having a plane of polarization that rotates; and a second transmission block that generates a second radio wave having the information signal modulated thereon and having a plane of polarization that is fixed. A receiver includes: a first receive section that demodulates a first radio wave having an information signal modulated thereon and having a plane of polarization that rotates; and a second receive section that demodulates a second radio wave having the information signal modulated thereon and having a plane of polarization that is fixed. The receiver restores the information signal on the basis of the result of reception by the first receive section and the second receive section.

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.

Aspects of the present disclosure provide a scheme for generating a multiple access (MA) signal that include mapping each of at least one stream of bits to generate a set of modulated symbols and transmitting the set of modulated symbols. The spreading signatures that are selected to map the at least one stream of bits are selected, at least in part, based on a set of compatibility rules. The spreading involves mapping each stream of bits using a respective spreading signature from a set of spreading signatures to generate a respective set of modulated symbols, wherein real spreading signature components of the spreading signatures are orthogonal to each other and imaginary spreading signature components of the spreading signatures are orthogonal to each other.

Disclosed are techniques for receiving reference radio frequency (RF) signals for positioning estimation. In an aspect, a receiver device receives, from a transmission point, a reference RF signal on a wireless channel receives, from a positioning entity, an indication that the reference RF signal serves as a source for a quasi-collocation (QCL) type(s) for positioning reference RF signals received by the receiver device from the transmission point on the wireless channel, measures an average delay, a delay spread, or both the average delay and the delay spread of the reference RF signal based on the QCL type(s), receives, from the transmission point, a positioning reference RF signal on the wireless channel, and identifies a time of arrival (ToA) of the positioning reference RF signal based on the measured average delay, the delay spread, or both the average delay and the delay spread of the reference RF signal.