Methods, systems, and devices for wireless communications are described. A first user equipment (UE) may receive, from a second UE, a capability message indicating that the second UE is capable of processing one or more types of modulated waveforms. The first UE may encode a set of orthogonal frequency division multiplexing (OFDM) symbols with a first set of data for an uplink transmission to a network entity via a communication link between the first UE and the network entity, and may modulate the set of encoded OFDM symbols with a second set of data for the second UE according to a type of the one or more types of modulated waveforms capable of being processed by the second UE. The first UE may transmit and the second UE may monitor for the modulated set of encoded OFDM symbols via the communication link.

Various features related to using a multi-port synchronization signal as reference for demodulating a multi-port broadcast channel are described. In an aspect, a synchronization signal, e.g., SSS, may be repurposed to serve as a demodulation reference for a downlink channel, e.g., PBCH, thereby obviating the need for a base station to send an additional reference signal for PBCH demodulation. A base station may select two or more logical antenna ports to transmit a synchronization signal, transmit the synchronization signal from the selected two or more logical antenna ports, and transmit information on the PBCH, from at least the selected two or more logical antenna ports. A UE may receive the synchronization signal from the two or more logical antenna ports at the base station, receive information on the PBCH from the at least the two or more logical antenna ports, and demodulate the information based on the received synchronization signal.

We disclose embodiments of a WDM transmitter having an in-band OTDR capability for at least a subset of the WDM channels thereof. In an example embodiment, an OTDR-enabled WDM channel of the WDM transmitter is implemented using an optical transceiver that comprises an optical transmitter and a coherent optical receiver. The optical transmitter is configured to generate a modulated optical signal by modulating a respective carrier wavelength, transmit the modulated optical signal through an optical link as a component of the corresponding WDM signal, and provide the respective carrier wavelength to the coherent optical receiver for being used therein as an optical local oscillator. The optical receiver is configured to estimate an impulse response of the optical link by coherently detecting and processing a return optical signal produced within the optical link due to distributed reflection and/or backscattering of the modulated optical signal.

A method of communicating, by a first device, with at least one second device in a wireless local area network (WLAN) system includes allocating at least one resource unit (RU) within a bandwidth to a second device; generating at least one subfield defining the at least one RU; generating a trigger frame comprising a user information field comprising the at least one subfield, and transmitting a PPDU including the trigger frame to the at least one second device, wherein the generating comprises setting at least seven bits associated with the at least one RU and setting at least two bits as a value defining a subband that includes the at least one RU when the band width comprises at least four subbands.

Systems, devices, and methods of the present invention enhance data transmission through the use of polynomial symbol waveforms (PSW) and sets of PSWs corresponding to a symbol alphabet is here termed a PSW alphabet. Methods introduced here are based on modifying polynomial alphabet by changing the polynomial coefficients or roots of PSWs and/or shaping of the polynomial alphabet, such as by polynomial convolution, to produce a designed PSW alphabet including waveforms with improved characteristics for data transmission.

A system for noise removal is coupled to a signal unit that provides a digital signal. The noise removal system includes a transformation module to transform the digital signal into an f-digital signal, a threshold filter to generate a noiseless signal from the f-digital signal based on a threshold profile, and a signal synthesizer to provide a gain to the noiseless signal and to transform the noiseless signal into an output signal.

A system for noise removal is coupled to a signal unit that provides a digital signal. The noise removal system includes a transformation module to transform the digital signal into an f-digital signal, a threshold filter to generate a noiseless signal from the f-digital signal based on a threshold profile, and a signal synthesizer to provide a gain to the noiseless signal and to transform the noiseless signal into an output signal.

A system for noise removal is coupled to a signal unit that provides a digital signal. The noise removal system includes a transformation module to transform the digital signal into an f-digital signal, a threshold filter to generate a noiseless signal from the f-digital signal based on a threshold profile, and a signal synthesizer to provide a gain to the noiseless signal and to transform the noiseless signal into an output signal.

A method of communicating, by a first device, with at least one second device in a wireless local area network (WLAN) system includes allocating at least one resource unit (RU) within a bandwidth to a second device; generating at least one subfield defining the at least one RU; generating a trigger frame comprising a user information field comprising the at least one subfield, and transmitting a PPDU including the trigger frame to the at least one second device, wherein the generating comprises setting at least seven bits associated with the at least one RU and setting at least two bits as a value defining a subband that includes the at least one RU when the band width comprises at least four subbands.

An optical transmitter has an optical modulator with a Mach-Zehnder interferometer, a pilot signal generator configured to generate a pilot signal to be superimposed on a drive signal for driving the optical modulator or on a substrate bias voltage applied to the optical modulator, and a controller configured to detect a ratio between a pilot component and a direct current component contained in a light output from the optical modulator and control at least one of an amplitude of the drive signal and a level of the substrate bias voltage such that the ratio becomes a constant value.