The invention is directed to systems and methods for quadrature spatial modulation in the transmission of over a wireless network. A plurality of transmit antennas are configured in a spaced apart configuration, with each antenna representative of a spatial constellation symbol comprising an in-phase component and a quadrature component. A transmission unit is configured to map source data to the spatial constellation symbol of the transmit antennas, and to transmit a carrier signal comprising the in-phase and quadrature components out of phase. At least one receiving antenna is configured to receive the carrier signal, and at least one receiving unit is configured to demodulate the carrier signal to generate the source data.

Embodiments are provided for guard band utilization for synchronous and asynchronous communications in wireless networks. A user equipment (UE) or a network component transmits symbols on data bands assigned for primary communications. The data bands are separated by a guard band having smaller bandwidth than the data bands. The UE or network component further modulates symbols for secondary communications with a spectrally contained wave form, which has a smaller bandwidth than the guard band. The spectrally contained wave form is achieved with orthogonal frequency-division multiplexing (OFDM) modulation or with joint OFDM and Offset Quadrature Amplitude Modulation (OQAM) modulation. The modulated symbols for the secondary communications are transmitted within the guard band.

A communication device includes a modulator, a first encoder and a second encoder, and generates a modulated signal with quadrature amplitude modulation. The modulator generates a modulated signal by mapping each symbol in a data frame that includes data, a first code, and a second code to a signal point among signal points of the quadrature amplitude modulation. The first encoder encodes the data by using a first coding scheme to generate the first code. The second encoder encodes, by using a second coding scheme, a bit string formed from a specified bit in a plurality of bits allocated to each symbol in the data frame to generate the second code. The modulator performs mapping such that each pair of adjacent signal points are different from each other in terms of a value of the specified bit in the plurality of bits.

A base station is configured to communicate with at least a first user equipment (UE) and a second UE, wherein the base station is configured to communicate with the first UE using a first modulation scheme, and with the second UE using a second, different, modulation scheme, wherein communications with the first and second UEs are arranged to be substantially orthogonal to each other. A method of allocating resources in a communication network comprising a base station operable to communicate with a first user equipment (UE) and a second UE, the method comprising using a first modulation scheme for communication with the first UE, and using a second, different, modulation scheme for communication with the second UE, wherein communications with the first and second UEs are configured to be substantially orthogonal to each other.

Aspects of the present disclosure describe scrambling of information for wireless communications to prevent deciphering or altering by unintended recipients. An example method may include generating, by a first device, a scrambling key based on at least one of a freshness parameter or a private key. The private key is known by the first device and a second device. The method also includes scrambling a payload based on the scrambling key at a physical layer. A packet includes the payload for wireless transmission from the first device to the second device via a shared channel.

A transmitter for transmitting payload data and emergency information using data symbols in a single-carrier or multi-carrier broadcast system includes a modulator configured to modulate one or more transmission symbols with signaling data for use in detecting and recovering the payload data at a receiver and to modulate one or more transmission symbols with the payload data. An emergency information receiver receives emergency information carrying information of an actual emergency. An emergency information embedder embeds emergency information into one or more transmission symbols, wherein the emergency information is embedded within a predetermined time period after its reception by using a resource used for carrying signaling data and/or payload data if no emergency information shall be transmitted. A transmission unit transmits the transmission symbols.

Analysis channelizers are provided. In one embodiment, the channelizer includes an M-path filter receiving an input signal; a circular buffer in communication with the M-path filter; and an M-point inverse fast Fourier transform (IFFT) circuit in communication with the circular buffer, such that the channelizer aligns spectra of the input signal with spectral responses an odd length, non-maximally decimated filter bank by alternating sign heterodyne of the input signal. The channelizer applies an equivalency theorem to the non-maximally decimated filter bank formed by an odd length polyphaser filter. Advantageously, the M-path filter does not require on-line signal processing to obtain odd-indexed filter centers. In another embodiment, the channelizer alternates a sign heterodyne of a filter coefficient weight.

In a transmitter apparatus, a known reference signal is superimposed on top of a data signal that is typically not known a priori to a receiver and the combined signal is transmitted. At a receiver, an iterative channel estimation and equalization technique is used to recover the reference signal and the unknown data signal. In the initial iteration, the known reference signal is recovered by treating the data signal as noise. Subsequent iterations are used to improve estimation of received reference signal and the unknown data signal.

Methods, systems, and devices for wireless communication are described. A communication device, such as, a base station and a UE may support transmitting and receiving information bits according to one or more index modulation schemes. For example, the communication device may support conveying information bits using a reference signal index modulation scheme, which uses reference signals transmissions using particular resources or reference signal sequences, or both, to convey the information bits. The communication device may improve reference signal resource usage by supporting a multi-mode reference signal index modulation scheme, which utilizes all reference signal resources to convey the information bits. By using the multi-mode reference signal index modulation scheme, the communication device may, as a result, include features for improvements to conveying information bits, among other benefits.

A data communication method in which input digital data is received and encoded into an encoded waveform having zero crossings representative of the input digital data. The encoding includes generating the encoded waveform based upon a continuous piecewise function having sinusoidal components. The continuous piecewise function may be used in generating a plurality of symbol waveforms, each of which occupies a period of the encoded waveform and represents bits of the input digital data. The plurality of symbol waveforms are defined so that a value of a phase offset used in the continuous piecewise function is different for each of the plurality of symbol waveforms, thereby resulting in each symbol waveform having a different zero crossing. An encoded analog waveform is generated from a representation of the encoded waveform and transmitted to a receiver.