Abstract: A radio transmitter adjusts its radio frequency (RF) fingerprint to defeat RF fingerprinting identification without destroying the content of its transmissions. The radio transmitter comprises a frequency-upconverter configured to upconvert a baseband or intermediate-frequency signal to an RF signal, and an amplifier to amplify the RF signal to produce a transmission signal. An RF fingerprint control circuit changes the non-linear behavior of the frequency-upconverter or the amplifier in order to change the RF fingerprint. The transmitter may create RF fingerprint “personalities” to be paired with different radio protocol behaviors and subscriber terminal identification codes (e.g., MAC addresses or SMSIs) for generating different radio identities.

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: 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 includes a bits-to-symbol mapper that produces a plurality of data symbols; and a waveform modulator that receives a first discrete-time waveform and at least a second discrete-time waveform that comprises a cyclic shift of the first discrete-time waveform; modulates a first one of the plurality of data symbols onto the first discrete-time waveform and modulates a second one of the plurality of second data symbol onto the second discrete-time waveform, to produce a plurality of modulated discrete-time waveforms; and sums the plurality of modulated discrete-time waveforms to produce a modulated discrete-time signal to be transmitted in the network. The first discrete-time waveform and at least the second discrete-time waveform are multicarrier signals.

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: 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: 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: 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 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.

Abstract: A wireless user equipment (UE) device is configured to communicate with another UE via device-to-device (D2D) communications. The UE transmits a communication to the other UE, wherein the communication indicates scheduling of a shared spectrum resource. The shared spectrum resource is shared by a first network management operator (NMO) and a second NMO, wherein both the UE and the other UE are associated with the first NMO. The first NMO employs a first set of spatial channels in the shared spectrum resource, and a second set of spatial channels in the shared spectrum resource is made available for use by the second NMO, the second set being different from the first set. The UE communicates with the other UE over the first set of spatial channels.

Abstract: An unmanned aerial vehicle (UAV) uses a first baseband processor to establish a first communication link with a ground station of a wireless network and a second baseband processor that establishes a second communication link with a user device. The second baseband processor for processing a radio transmission from a user equipment. The second baseband processor is communicatively coupled to the first baseband processor such that the radio transmission is communicated to the ground station via the first communication link. Flight-control hardware steers the UAV along a flight trajectory that is determined by a ground-based UAV controller based at least on the radio transmission, such that the UAV or the ground station can locate or track the user equipment.

Abstract: A receiver in a wireless communications network demodulates and decodes received Carrier Interferometry (CI) signals. A demodulator demodulates a received multicarrier signal into demodulated symbols, wherein the plurality of demodulated symbols are CI-coded data symbols. A CI decoder decodes the CI-coded data symbols to produce data symbol estimates. The CI decoder can employ an inverse of a transform, such as a Fourier transform, used by a transmitter to provide the multicarrier signal with a low peak-to-average-power ratio.