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.

Aspects of the present disclosure describe a system and method for synchronizing time, frequency, and phase among a plurality of devices.

Aspects of the present disclosure describe a system and method for synchronizing time, frequency, and phase among a plurality of devices.

Aspects of the present disclosure describe a system and method for synchronizing time, frequency, and phase among a plurality of devices.

Aspects of the present disclosure describe a system and method for synchronizing time, frequency, and phase among a plurality of devices.

Disclosed herein are system, apparatus, article of manufacture, method and/or computer program product embodiments, and/or combinations and sub-combinations thereof, for synchronizing playback of audiovisual content with a dumb speaker. In some embodiments, a display device transmits a spread spectrum signal to a dumb speaker over a data channel using a spread spectrum code. The display device then receives the spread spectrum signal from the dumb speaker over an audio data channel. The display device despreads the spread spectrum signal based on the spreading code. The display device determines a time of receipt of the spread spectrum signal. The display device calculates an audiovisual output path delay for the dumb speaker based on the time of receipt and a time of transmission. The display device then synchronizes the playback of the audiovisual content at the dumb speaker and a smart speaker based on the audiovisual output path delay.

Disclosed herein are system, apparatus, article of manufacture, method and/or computer program product embodiments, and/or combinations and sub-combinations thereof, for synchronizing playback of audiovisual content with a dumb speaker. In some embodiments, a display device transmits a spread spectrum signal to a dumb speaker over a data channel using a spread spectrum code. The display device then receives the spread spectrum signal from the dumb speaker over an audio data channel. The display device despreads the spread spectrum signal based on the spreading code. The display device determines a time of receipt of the spread spectrum signal. The display device calculates an audiovisual output path delay for the dumb speaker based on the time of receipt and a time of transmission. The display device then synchronizes the playback of the audiovisual content at the dumb speaker and a smart speaker based on the audiovisual output path delay.

A method for piloting from bypass in a network with open wireless channels is disclosed. The method includes: 1) selecting a terminal station as a reference in open wireless channels, and sending a pilot signal, in which all or some frequency bands of open wireless channels occupied by the pilot signal are pilot frequency bands, and the proportion of power of the pilot signal to the total power of the pilot frequency bands is 0.1‰-5%; 2) spreading the pilot signal with a spread spectrum code when it is transmitted, and then superimposing on a communication signal in the pilot frequency bands in a low power spectrum signal mode similar with noise; and 3) providing pilot, carrier wave and clock synchronization, standard timing and indication information for network construction and mutual communication of multiple types of terminal stations in channels by the pilot signal.

The present disclosure may be embodied as a transmitter for multiuser multicarrier-chirp-division-multiplexing (“MU-MCDM”) communications. The present disclosure may be embodied as a receive for MU-MCDM communications. The present disclosure may also be embodied as a method for transmitting an MU-MCDM communication signal. The present disclosure may also be embodied as a method for receiving an MU-MCDM communication signal.

The present disclosure may be embodied as a transmitter for multiuser multicarrier-chirp-division-multiplexing (“MU-MCDM”) communications. The present disclosure may be embodied as a receive for MU-MCDM communications. The present disclosure may also be embodied as a method for transmitting an MU-MCDM communication signal. The present disclosure may also be embodied as a method for receiving an MU-MCDM communication signal.