Methods and apparatuses disclosed herein enable the use of Demodulation Reference Signal, DMRS, sequences that are numbered relative to an overall system bandwidth, while simultaneously enabling wireless communication devices to determine the DRMS sequence elements mapped to their scheduled bandwidths within the system bandwidth. Advantageously, the wireless communication devices need not know the system bandwidth, or even be aware of where their scheduled bandwidths reside within the system bandwidth.

As may be used in connection with frequency-modulated (FM) radio systems and receivers processing FM broadcast transmissions, exemplary aspects are directed to a method may be performed by the receiver circuitry to receive FM broadcast signaling within a particular bandwidth for which a plurality of target channels are to have a specified channel spacing. The method may include: assessing detected energy for a first adjacent channel having the specified channel spacing and having a frequency immediately adjacent to a targeted one of the plurality of target channels; and discerning whether the detected energy is associated with ultra-sonic energy in detected modulation energy (e.g., ultra-sonic noise in an MPX signal), and/or is associated with modulation energy (e.g., due to over-modulation) from a second adjacent channel also having such specified channel spacing.

A digital transmission system includes a transmitter configured to transmit an orthogonal frequency division multiplexing (OFDM) signal along a signal path, a receiver for receiving the OFDM signal from the transmitter and extracting OFDM symbols from the received OFDM signal, and a diagnostic unit configured to (i) demodulate the received OFDM signal to create an ideal signal, (ii) compare the received OFDM signal with the ideal signal to calculate an error signal, (iii) cross-correlate the error signal with the ideal signal, and (iv) determine a level nonlinear distortion from one of the transmitter and the signal path based on the correlation of the error signal with the ideal signal.

A system that incorporates aspects of the subject disclosure may perform operations including, for example, receiving, via an antenna, a signal generated by a communication device, detecting passive intermodulation interference in the signal, the interference generated by one or more transmitters unassociated with the communication device, and the interference determined from signal characteristics associated with a signaling protocol used by the one or more transmitters. Other embodiments are disclosed.

A central challenge in next-generation 5G/6G networks is achieving high message reliability despite very dense usage and unavoidable signal fading at high frequencies. To provide enhanced fault detection, localization, and mitigation, the disclosed procedures can enable an AI model (or an algorithm derived from it) to discriminate between faulted and unfaulted message elements according to signal quality, modulation parameters, and other inputs. The AI model can estimate the likelihood that each message element is faulted, and predict the most probable corrected value, among other outputs. The AI model can also consider the quality of a demodulation reference used to demodulate the message, and the quality of the associated error-detection code. The AI model can also consider previously received messages to the same receiver, or messages of a similar type. Fault mitigation by the receiver can save substantial time and resources by avoiding a retransmission. Many other aspects are disclosed.

A system that incorporates aspects of the subject disclosure may perform operations including, for example, receiving, via an antenna, a signal generated by a communication device, detecting passive intermodulation interference in the signal, the interference generated by one or more transmitters unassociated with the communication device, and the interference determined from signal characteristics associated with a signaling protocol used by the one or more transmitters. Other embodiments are disclosed.

Systems and methods for mitigation of cross channel interference are disclosed in which the TDD configuration of a potential cross channel interference source is detected by received signals within the network with which the source interferes. The TDD configuration is then used to synchronize the transmissions from the network with which the source interferes to reduce the interference. In addition, interference is mitigated by providing adaptive guard bands based on results of a radio frequency environmental survey and/or coaxing an interfering user to another channel. Sub-channels can be assigned based on the results of the radio frequency environmental survey and Quality of Service requirements for traffic flows.

Apparatus and methods for providing interference management and load balancing in a wireless network. In one embodiment, the method and apparatus utilize quasi-licensed CBRS (Citizens Broadband Radio Service) wireless spectrum in conjunction with enhanced SAS (Spectrum Access System) and base station (e.g., CBSD) components to enable creation and management of virtual clusters of bases stations connected to the network, so as to enable inter-cluster interference mitigation, while also supporting load balancing between the base stations using coverage area overlap. In one implementation, the SAS reduces the coverage area (transmit power) of one or more base stations on a cluster edge to mitigate inter-cluster interference, and increases or adjusts the coverage of one or more base stations inside of the cluster to enable load balancing.

A plurality of multicarrier signals is generated. Each of the plurality of multicarrier signals includes a pilot symbol sequence at a same temporal point in each multicarrier signal. Each pilot symbol sequence includes a plurality of pilot symbols with non-zero amplitude. The pilot symbol sequences are orthogonal to each other at the same temporal point. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of multicarrier signals to be transmitted. The plurality of multicarrier signals are transmitted in an identical frequency band from a plurality of antennas. The plurality of antennas includes two, three, or four antennas.

Provided are a data modulation method and apparatus, a device, and a storage medium. The data modulation method includes that: a modulation manner is configured, where a constellation point modulation symbol of the modulation manner is formed by combining a first group of constellation point modulation symbols and a second group of constellation point modulation symbols; and data is modulated by using the modulation manner, where the data includes a first data block and a second data block, the first data block is modulated by the first group of constellation point modulation symbols, and the second data block is modulated by the second group of constellation point modulation symbols.