Abstract: A receiver receives a multicarrier signal from a wireless communication network and determines subcarrier values of the multicarrier signal. A decoder decodes the subcarrier values to produce a set of data symbols. The multicarrier signal is characterized by a set of modulated pulse waveforms, which results from a sum of the subcarriers. Each of the modulated pulse waveforms has a different time offset. The decoder employs a set of codes for decoding the baseband signal, wherein each code comprises a different linearly increasing phase. Each of the linearly increasing phases corresponds to one of the different time offsets.

Abstract: Applications of CI processing to ad-hoc and peer-to-peer networking significantly improve throughput, network capacity, range, power efficiency, and spectral efficiency. CI-based subscriber units perform network-control functions to optimize network performance relative to channel conditions, network loads, and subscriber services. CI codes are used to identify and address network transmissions. Channel characteristics of communication links are employed to encode, address, and authenticate network transmissions. CI transceivers used as relays and routers employ unique characteristics of transmission paths to code and decode network transmissions. A central processor is adapted to perform array processing with signals received from, and transmitted by, a plurality of subscriber units in a wireless network.

Abstract: An apparatus for communication in a wireless communication network comprises a coder that encodes a set of data symbols to produce a set of coded symbols; a modulator that modulates the coded symbols onto a set of subcarrier frequencies to generate a time-domain signal comprising a sum of a set of modulated pulse waveforms; and a transmitter configured for transmitting the time-domain signal in the wireless communication network. The coder employs a matrix of spreading codes, wherein each column of the matrix multiplies a different one of the data symbols, which causes the modulator to produce a corresponding one of the set of modulated pulse waveforms. Each column of the matrix of spreading codes comprises a set of linearly increasing phases, which provides a time offset to the corresponding modulated pulse waveforms.

Abstract: An apparatus for communication in a wireless communication network comprises a coder that encodes a set of data symbols to produce a set of coded symbols; a modulator that modulates the coded symbols onto a set of subcarrier frequencies to generate a time-domain signal comprising a sum of a set of modulated pulse waveforms; and a transmitter configured for transmitting the time-domain signal in the wireless communication network. The coder employs a matrix of spreading codes, wherein each column of the matrix multiplies a different one of the data symbols, which causes the modulator to produce a corresponding one of the set of modulated pulse waveforms. Each column of the matrix of spreading codes comprises a set of linearly increasing phases, which provides a time offset to the corresponding modulated pulse waveforms.

Abstract: An apparatus that communicates in a mobile radio communications network, comprises signal-processing circuitry for provisioning a consecutive series of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers for uplink or downlink communications; provisioning a plurality of different selectable subcarrier spacings for the consecutive series of OFDM subcarriers; performing discrete Fourier transform (DFT) coding on a plurality of data symbols to produce DFT coded symbols; and performing an inverse-DFT on the coded symbols to produce a single-carrier frequency division multiple access signal that comprises a sum of the consecutive series of OFDM subcarriers. The single-carrier frequency division multiple access signal is provided with a particular one of a set of different symbol periods by selecting one of the plurality of different selectable subcarrier spacings.

Abstract: A user equipment (UE) in a wireless network employs orthogonal polyphase codes for encoding data symbols to generate a set of coded data symbols, which are modulated onto Orthogonal Frequency Division Multiplex (OFDM) subcarrier frequencies assigned for use by the UE, and the resulting OFDM signal is transmitted to a base station in the wireless network. The orthogonal polyphase codes include pairs of orthogonal polyphase codes that are complex conjugates of each other.

Abstract: A transmitter in a wireless communication network comprises a Carrier Interferometry (CI) coder and a multicarrier modulator communicatively coupled to the CI coder. The CI coder encodes a plurality of data symbols with a plurality of CI codes to produce a plurality of CI symbol values, wherein each of the plurality of CI symbol values equals a sum of information-modulated CI code chips. Each information-modulated CI code chip equals a CI code chip multiplied by one of the plurality of data symbols. The modulator modulates each CI symbol value onto a different subcarrier frequency to produce a multicarrier signal.

Abstract: In a multiuser (MU) multiple antenna system (MAS), a central processing unit is communicatively coupled to multiple distributed wireless terminals (WTs) via a network. The central processing unit processes channel measurements indicative of channel conditions between the multiple distributed WTs and a plurality of user devices and selects a plurality of WTs from the multiple distributed WTs to enhance channel space diversity within the MU-MAS. The central processing unit calculates (Multiple Input, Multiple Output) MIMO weights from the channel measurements for precoding a plurality of data streams that are transmitted concurrently from the plurality of WTs to the plurality of users, wherein the MIMO weights provide for a plurality of independent MIMO channels.

Abstract: A method for receiving an Orthogonal Frequency Division Multiplexing (OFDM) signal transmitted by a user device in a wireless network comprises determining which subcarrier frequencies are allocated to the user device; converting the OFDM signal to a frequency-domain values corresponding to the subcarrier frequencies; and decoding the frequency-domain values to recover data symbols encoded by the user device on the subcarrier frequencies. The decoding employs codes that are inverse to, complex-conjugate of, or complementary to a set of complex-valued codes employed by the user device to shape the OFDM signal into a superposition of cyclic-shifted pulse waveforms, wherein each of the pulse waveforms has one of the data symbols modulated thereon.

Abstract: A flexible channel bandwidth for mobile radio communications is provided by provisioning a set of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers for mobile radio communications; encoding data symbols with polyphase codes derived from a discrete Fourier transform to produce encoded data symbols; and modulating the encoded data symbols onto the OFDM subcarriers to produce a superposition signal that resembles a single-carrier signal and has one of a plurality of different symbol durations. The provisioning comprises selecting one of a plurality of different selectable subcarrier spacings, to provide for the one of the plurality of different symbol durations.

Abstract: A user device communicates in a wireless network by encoding a set of data symbols with a set of complex-valued codes to produce a set of subcarrier values. The subcarrier values are modulated onto a set of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers assigned to the user device to produce a time-domain waveform that comprises a superposition of modulated subcarriers, and the time-domain waveform is transmitted in the wireless network. The set of subcarrier values comprises a first polyphase code that encodes a first of the set of data symbols and at least a second polyphase code that encodes at least a second of the set of data symbols.

Abstract: Disclosed techniques for improving computational efficiency can be applied to synthesis and analysis in digital signal processing. A base discrete-time Orthogonal Frequency Division Multiplexing (OFDM) signal is generated by performing at least one linear transform, including an inverse discrete Fourier transform (IDFT), on a first matrix of data symbols. A sparse data matrix is provided as an update to the first matrix of data symbols. The at least one linear transform is performed on the sparse data matrix to generate an update discrete-time OFDM signal. The update discrete-time OFDM signal and the base discrete-time OFDM signal are summed to produce an updated discrete-time OFDM signal.

Abstract: A transmitter in a wireless communication network comprises a Carrier Interferometry (CI) coder and a multicarrier modulator communicatively coupled to the CI coder. The CI coder encodes a plurality of data symbols with a plurality of CI codes to produce a plurality of CI symbol values, wherein each of the plurality of CI symbol values equals a sum of information-modulated CI code chips. Each information-modulated CI code chip equals a CI code chip multiplied by one of the plurality of data symbols. The modulator modulates each CI symbol value onto a different subcarrier frequency to produce a multicarrier signal.

Abstract: A transmitter in a wireless communication network encodes data bits of a first layer to produce a set of coded symbols; spreads the coded symbols using discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM); and modulates the spread symbols onto a set of OFDM subcarrier frequencies to produce a discrete-time OFDM signal. Spreading is configured to map the coded symbols to a first sparse DFT-s-OFDM code space in a DFT-s-OFDM symbol, wherein the first sparse DFT-s-OFDM code space is different from a second sparse DFT-s-OFDM code space in the DFT-s-OFDM symbol, the second sparse DFT-s-OFDM code space being employed by a second layer.

Abstract: 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.

Abstract: 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.

Abstract: The disclosure relates in some aspects to providing a flexible channel bandwidth in a mobile radio communications network. For example, wherein a consecutive series of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers may be provisioned for uplink or downlink communications, a flexible frame structure may be provided by provisioning different subcarrier spacings for the consecutive series of OFDM subcarriers. The different subcarrier spacings may be used for transmitting and/or receiving OFDM signals.

Abstract: Systems, methods, and apparatuses for analyzing and synthesizing wireless communication signals are provided. A receiver might transform a received signal into a basis in which the transformed signal is sparse, which can reduce the complexity of joint detection by facilitating message passing algorithm (MPA) decoding. A transmitter might employ dense codewords in a first basis, which may facilitate certain signal-processing operations and may provide a transmission with a low peak-to-average-power ratio. The codewords can be designed to be sparse when transformed to a second basis. The codewords may be configured for non-orthogonal multiple access.

Abstract: A cooperative multi-user multiple input, multiple output (MIMO) antenna array comprises a MIMO subspace processing system communicatively coupled by a fronthaul network to a set of antennas residing on multiple ones of a plurality of geographically distributed wireless terminals in a Radio Access Network. The MIMO subspace processing system can comprise a distributed computing system. The MIMO antenna array is adapted by updating the set of antennas to produce a second set of antennas; reconfiguring the fronthaul network; selecting an updated set of distributed computing resources to perform MIMO subspace processing; and reconfiguring the MIMO subspace processing to employ channel state information of the second set to enable multiple non-interfering subspace channels occupying a common frequency.

Abstract: Disclosed techniques for improving computational efficiency can be applied to synthesis and analysis in digital signal processing. A base discrete-time Orthogonal Frequency Division Multiplexing (OFDM) signal is generated by performing at least one linear transform, including an inverse discrete Fourier transform (IDFT), on a first matrix of data symbols. A sparse data matrix is provided as an update to the first matrix of data symbols. The at least one linear transform is performed on the sparse data matrix to generate an update discrete-time OFDM signal. The update discrete-time OFDM signal and the base discrete-time OFDM signal are summed to produce an updated discrete-time OFDM signal.