A radio frequency, RF, transmitter, comprises a digitally controlled oscillator, DCO, configured to generate an RF signal; and digital modulation circuitry connected to the DCO for modulation of the RF signal, and driven by an RF clock signal derived from the RF signal, wherein the digital modulation circuitry comprises a module configured to apply a compensation for modulation jitter due to the modulation circuitry being driven by the RF clock signal and a compensation for DCO non-linearity.

A method for providing digital communication over an acoustic channel is disclosed. The method includes dividing an operating frequency band of the acoustic channel into multiple adjacent non-overlapping subbands of an equal bandwidth, selecting subbands based on a symbol to be transmitted, generating a signal with linear frequency modulation in each of the selected subbands, combining the signals with linear frequency modulation, and transmitting the combined signals to the acoustic channel through an acoustic system, wherein slopes of linear frequency modulation for the signals with linear frequency modulation are equal.

A receiving device includes an equalization processor including multiple delay equalizers. The equalization processor is configured to: obtain a first error between an output of one specific tap in the multiple delay equalizers and a predetermined reference value, and calculate a first weight with which the first error is minimized; cause a calculation result of the first weight to be reflected in all taps in the multiple delay equalizers except the specific tap, obtain a second error between outputs of all taps in the multiple delay equalizers and the predetermined reference value, and calculate a second weight with which the second error is minimized; and update coefficients of all taps in the multiple delay equalizers at the same timing using the calculation result of the first weight and a calculation result of the second weight, and calculate an output of the equalization processor.

An apparatus is disclosed, comprising means for identifying a plurality of user equipment (UE), each transmitting one or more uplink packets for decoding at a base station associated with a given cell of a radio network. The apparatus further comprises means for clustering the identified user equipment into joint processing groups, each joint processing group comprising the identities of two or more user equipment as clustered and means for performing, in a first processing stage, joint processing of the uplink data streams for identified user equipment within common joint processing groups using one or more first processing algorithms to produce corresponding first processed uplink data streams. The apparatus further discloses means for performing one or more subsequent processing stages on the first processed uplink data streams, subsequent to the joint processing, to produce decoded uplink data streams, the one or more subsequent processing stages using one or more second processing algorithms, different from the first processing algorithm.

An apparatus is disclosed, comprising means for identifying a plurality of user equipment (UE), each transmitting one or more uplink packets for decoding at a base station associated with a given cell of a radio network. The apparatus further comprises means for clustering the identified user equipment into joint processing groups, each joint processing group comprising the identities of two or more user equipment as clustered and means for performing, in a first processing stage, joint processing of the uplink data streams for identified user equipment within common joint processing groups using one or more first processing algorithms to produce corresponding first processed uplink data streams. The apparatus further discloses means for performing one or more subsequent processing stages on the first processed uplink data streams, subsequent to the joint processing, to produce decoded uplink data streams, the one or more subsequent processing stages using one or more second processing algorithms, different from the first processing algorithm.

A communication system in which a hub station and multiple terminal stations communicate at the same time using the same channel The hub station generates a transmission signal, generates a cancellation signal combines the transmission signal regarding the transmission signal and the cancellation signal, transmits the combined signal, and calculates an adaptive filter minimizing a power of an error signal with respect to the known signal. The terminal station calculates the error signal, generates the known signal for a terminal station causing interference in the interference signal, calculates a correction amount of a filter coefficient in the adaptive filter, and transmits the correction amount. The hub station calculates an adaptive filter calculates the filter coefficient based on the correction amount, and generates the cancellation signal by performing a filtering process using the adaptive filter on the signal to be transmitted to the other of the terminal stations.

A method for providing digital communication over an acoustic channel is disclosed. The method includes dividing an operating frequency band of the acoustic channel into multiple adjacent non-overlapping subbands of an equal bandwidth, selecting subbands based on a symbol to be transmitted, generating a signal with linear frequency modulation in each of the selected subbands, combining the signals with linear frequency modulation, and transmitting the combined signals to the acoustic channel through an acoustic system, wherein slopes of linear frequency modulation for the signals with linear frequency modulation are equal.

An apparatus is disclosed, comprising means for identifying a plurality of user equipment (UE), each transmitting one or more uplink packets for decoding at a base station associated with a given cell of a radio network. The apparatus further comprises means for clustering the identified user equipment into joint processing groups, each joint processing group comprising the identities of two or more user equipment as clustered and means for performing, in a first processing stage, joint processing of the uplink data streams for identified user equipment within common joint processing groups using one or more first processing algorithms to produce corresponding first processed uplink data streams. The apparatus further discloses means for performing one or more subsequent processing stages on the first processed uplink data streams, subsequent to the joint processing, to produce decoded uplink data streams, the one or more subsequent processing stages using one or more second processing algorithms, different from the first processing algorithm.

An apparatus is disclosed, comprising means for identifying a plurality of user equipment (UE), each transmitting one or more uplink packets for decoding at a base station associated with a given cell of a radio network. The apparatus further comprises means for clustering the identified user equipment into joint processing groups, each joint processing group comprising the identities of two or more user equipment as clustered and means for performing, in a first processing stage, joint processing of the uplink data streams for identified user equipment within common joint processing groups using one or more first processing algorithms to produce corresponding first processed uplink data streams. The apparatus further discloses means for performing one or more subsequent processing stages on the first processed uplink data streams, subsequent to the joint processing, to produce decoded uplink data streams, the one or more subsequent processing stages using one or more second processing algorithms, different from the first processing algorithm.

A method for providing digital communication over an acoustic channel is disclosed. The method includes dividing an operating frequency band of the acoustic channel into multiple adjacent non-overlapping subbands of an equal bandwidth, selecting subbands based on a symbol to be transmitted, generating a signal with linear frequency modulation in each of the selected subbands, combining the signals with linear frequency modulation, and transmitting the combined signals to the acoustic channel through an acoustic system, wherein slopes of linear frequency modulation for the signals with linear frequency modulation are equal.