A High-Order PSK Signaling (HOPS) communications system which adapts sequence-based spread spectrum signaling techniques to the needs of low-power commercial standards. A HOPS signal generation apparatus incudes a seed calculator configured to calculate a series of seed vectors in response to a plurality of time-evolving key values wherein each of the seed vectors includes a plurality of index values calculated based upon the current key values. A sequence generator is configured to generate a series of time-evolving spreading sequences using the series of seed vectors. A modulator is operative to generate the communications signal by spreading the data signal using the spreading sequences. A transmitter transmits an analog version of the communications signal.

Methods, systems, and devices for wireless communications are described. In some wireless systems, different wireless devices may communicate using different radio access technologies (RATs) in a shared radio frequency spectrum. Prior to communicating on a channel in the shared radio frequency spectrum, a wireless device may transmit a training field as part of a preamble in a transmission on the channel to reserve the channel for the transmission. As described herein, a training field transmitted by a wireless device using one RAT may be transmitted with an autocorrelation property associated with training fields of another RAT. As such, a wireless device configured to communicate using the other RAT may be able to receive and identify the training field (e.g., based on the autocorrelation property), and the wireless device may use the additional techniques described herein to determine an availability of the channel based on the training field.

Certain disclosed methods, apparatus, and systems enable improved communication on a multiphase communication link through improved encoding techniques and protocol. A data communication apparatus has a plurality of line drivers configured to couple the apparatus to a 3-wire link, and a data encoder configured to encode at least 3 bits of binary data in each transition between two symbols that are consecutively transmitted by the plurality of line drivers over the 3-wire link such that each pair of consecutively-transmitted symbols comprises two different symbols. Each symbol defines signaling states of the 3-wire link during an associated symbol transmission interval such that each wire of the 3-wire link is in a different signaling state from the other wires of the 3-wire link during the associated symbol transmission interval. Data may be encoded using a combination of 3-phase and pulse amplitude modulation.

System and method for processing an analog signal. For example, a demodulator for processing an analog signal includes one or more analog-to-digital converters configured to receive an analog signal and generate a digital signal based at least in part on the analog signal, and a correlator coupled to the one or more analog-to-digital converters and configured to generate a stream of correlation results including a first plurality of correlation results, a second plurality of correlation results, and a third plurality of correlation results. The first plurality of correlation results is different from the second plurality of correlation results by at least one correlation result, and the second plurality of correlation results is different from the third plurality of correlation results by at least another correlation result.

Embodiments of the present application provide a method for acquiring information of access resources, a terminal device, and a base station. A terminal device detects a synchronization signal of a cell to be accessed by the terminal device. The terminal device further receives a broadcast channel of the cell on a broadcast channel resource. The terminal device then determines a resource on which the cell is located according to resource indication information carried in the broadcast channel. The broadcast channel resource corresponds to an actual access resource, and the synchronization signal is detected on the actual access resource. The actual access resource is one of a plurality of candidate access resources of the cell. The resource indication information indicates a location relationship between the actual access resource and the resource on which the cell is located.

The present disclosure provides a method for compensating an imbalance between an I path and a Q path of a receiver. The method includes: sending a cosine signal and a sine signal through a signal generator, transmitting the cosine signal and the sine signal in the I path and Q path respectively; calculating autocorrelation values of the I path and the Q path in the signal receiving direction; determining a comparison result of amplitudes of the cosine signal received by the I path and the sine signal received by the Q path according to the autocorrelation values; calculating an adjustment compensation value of an analog domain gain amplifier, and an amplitude value and a phase value in a digital domain according to the comparison result of amplitudes; and compensating and adjusting the signal according to the adjustment compensation value, the amplitude value and the phase value.

Aspects of the subject disclosure may include, for example, a system for modulating a first electrical signal to generate first modulated electromagnetic waves, and transmitting the first modulated electromagnetic waves on a waveguide located in proximity to a transmission medium. In one embodiment, the first electromagnetic waves can induce second electromagnetic waves that propagate on an outer surface of the transmission medium. The second electromagnetic waves can have a first spectral range that is divided into, contains or otherwise includes a first control channel and a first plurality of bands. Other embodiments are disclosed.

A synchronizer generates cross-products of In-phase (I) and Quadrature (Q) samples and stores the sign bits for the sine and cosine cross-products. The sign bits are compared to a local reference of a frame-start bit-sequence and the compare results accumulated as I and Q correlations for symbol and half-symbol sampling. Linear combinations of the accumulated I and Q correlations for the symbol and half-symbol sampling generate linear combination results for frequency bins that peak at a different implied Carrier Frequency Offset (CFO) settings. The maximum of the linear combination results is selected and the implied CFO setting for that frequency bin is applied to a demodulator to adjust the receiver's CFO setting and bit synchronization. Computational complexity is reduced since only the sign bit of each cross-product is retained for correlation with the frame-start bit-sequence. Linear combinations can support a wide CFO range.

A signal receiver for receiving a HOPS-based communications signal includes a seed calculator configured to produce a series of seed vectors generated from a corresponding series of sets of key values. A sequence generator provides a series of internally generated sequences using the series of seed vectors. A fallthrough correlator produces a series of correlation values by correlating samples of a received signal and samples of the internally generated sequences. The spreading sequences are used by a transmitter to generate a transmit signal subsequently received as the received signal. A peak detector is configured to generate a trigger signal upon determining that at least one of the correlation values exceeds a threshold value. At least one of a plurality of demodulator chains is selected in response to the trigger signal and used to demodulate the received signal in order to recover data values carried by the received signal.

Example communication systems and methods are described. In one implementation, a method receives a first chaotic sequence of a first temporal length, and a second chaotic sequence of a second temporal length. The method also receives a data symbol for communication to a destination. Based on the data symbol, the second chaotic sequence is temporally shifted and combined with the first chaotic sequence to generate a composite chaotic sequence. The first chaotic sequence functions as a reference chaotic sequence while the second chaotic sequence functions as a data-carrying auxiliary chaotic sequence.