A distributed radio frequency communication system facilitates communication between a wireless terminal and a core network. The system includes a remote radio unit (RRU) coupled to at least one antenna to communicate with the wireless terminal. The RRU includes electronic circuitry to perform at least a first portion of a first-level protocol of a radio access network (RAN) for communicating between the wireless terminal and the core network. The system also includes a baseband unit (BBU) coupled to the core network, and configured to perform at least a second-level protocol of the RAN. A fronthaul link is coupled to the BBU and the RRU. The fronthaul link utilizes an adaptive fronthaul protocol for communication between the BBU and the RRU. The adaptive fronthaul protocol has provisions for adapting to conditions of the fronthaul link and radio network by changing the way data is communicated over the fronthaul link.

A distributed radio frequency communication system facilitates communication between a wireless terminal and a core network. The system includes a remote radio unit (RRU) coupled to at least one antenna to communicate with the wireless terminal. The RRU includes electronic circuitry to perform at least a first portion of a first-level protocol of a radio access network (RAN) for communicating between the wireless terminal and the core network. The system also includes a baseband unit (BBU) coupled to the core network, and configured to perform at least a second-level protocol of the RAN. A fronthaul link is coupled to the BBU and the RRU. The fronthaul link utilizes an adaptive fronthaul protocol for communication between the BBU and the RRU. The adaptive fronthaul protocol has provisions for adapting to conditions of the fronthaul link and radio network by changing the way data is communicated over the fronthaul link.

Disclosed is a device (1) for processing an initial audio signal (4), including: a treble detecting block (2) capable of analyzing the initial audio signal to determine a treble level; and a filter block (3) capable of attenuating the initial audio signal in the treble, if the treble level is less than a maximum threshold.

A distributed radio frequency communication system includes a remote radio unit (RRU and a baseband unit (BBU) and facilitates communication between a wireless terminal and a core network. The RRU receives a radio frequency signal from a wireless terminal and convert the radio frequency signal to digital baseband samples using receiver circuitry and an analog-to-digital converter. The RRU then adaptively compresses the digital baseband samples, using adaptive compression circuitry, to create fronthaul uplink information, and sends the fronthaul uplink information over a fronthaul link to the BBU using an adaptive fronthaul protocol. The RRU also receives fronthaul downlink information over a fronthaul link from the BBU using an adaptive fronthaul protocol and generates frequency-domain samples, based on the fronthaul downlink information received. It then creates time-domain baseband samples from the frequency-domain samples and converts the time-domain baseband samples into a radio frequency signal to send to the wireless terminal.

A signal input from a microphone is A-D converted by an A-D converter, is frequency differentiated by a pre-emphasis circuit, and is input to a shift control circuit. The shift control circuit includes a limiter circuit, a phase shifter, and a harmonic suppressor. The limiter circuit performs amplitude limitation so as to limit the amplitude of the input control target signal to be equal to or less than a first threshold. The phase shifter shifts, for the control target signal having the amplitude limited, a phase of a frequency component within the predetermined frequency range. The harmonic suppressor suppresses, for the control target signal phase-shifted by the phase shifter, a frequency component equal to or greater than a second threshold, and outputs an information signal that is the control target signal having the frequency component of equal to or greater than the second threshold suppressed. The modulator performs frequency modulation on a carrier wave in accordance with the information signal. The transmitter produces a transmission signal from the frequency-modulated carrier wave, and transmits the transmission signal via an antenna.

A distributed radio frequency communication system facilitates communication between a wireless terminal and a core network. The system includes a remote radio unit (RRU) coupled to at least one antenna to communicate with the wireless terminal. The RRU includes electronic circuitry to perform at least a first portion of a first-level protocol of a radio access network (RAN) for communicating between the wireless terminal and the core network. The system also includes a baseband unit (BBU) coupled to the core network, and configured to perform at least a second-level protocol of the RAN. A fronthaul link is coupled to the BBU and the RRU. The fronthaul link utilizes an adaptive fronthaul protocol for communication between the BBU and the RRU. The adaptive fronthaul protocol has provisions for adapting to conditions of the fronthaul link and radio network by changing the way data is communicated over the fronthaul link.

An acoustic processing apparatus includes a storage, an estimation unit, and a removal unit. The storage stores therein a reference signal indicating a signal obtained by completing removal of reverberation from a first observation signal included in a first processing section. The estimation unit estimates, on the basis of a model representing an observation signal as a signal obtained by adding a signal obtained by applying a reverberation removal filter to an acoustic signal that is input with a delay and the acoustic signal, a filter coefficient of the reverberation removal filter by using a second observation signal and the reference signal. The removal unit determines an output signal indicating a signal obtained by removing reverberation from the second observation signal by using the second observation signal, the reference signal, and the reverberation removal filter having the estimated filter coefficient.

A distributed radio frequency communication system facilitates communication between a wireless terminal and a core network. The system includes a remote radio unit (RRU) coupled to at least one antenna to communicate with the wireless terminal. The RRU includes electronic circuitry to perform at least a first portion of a first-level protocol of a radio access network (RAN) for communicating between the wireless terminal and the core network. The system also includes a baseband unit (BBU) coupled to the core network, and configured to perform at least a second-level protocol of the RAN. A fronthaul link is coupled to the BBU and the RRU. The fronthaul link utilizes an adaptive fronthaul protocol for communication between the BBU and the RRU. The adaptive fronthaul protocol has provisions for adapting to conditions of the fronthaul link and radio network by changing the way data is communicated over the fronthaul link.

An acoustic processing apparatus includes a storage, an estimation unit, and a removal unit. The storage stores therein a reference signal indicating a signal obtained by completing removal of reverberation from a first observation signal included in a first processing section. The estimation unit estimates, on the basis of a model representing an observation signal as a signal obtained by adding a signal obtained by applying a reverberation removal filter to an acoustic signal that is input with a delay and the acoustic signal, a filter coefficient of the reverberation removal filter by using a second observation signal and the reference signal. The removal unit determines an output signal indicating a signal obtained by removing reverberation from the second observation signal by using the second observation signal, the reference signal, and the reverberation removal filter having the estimated filter coefficient.

A distributed radio frequency communication system includes a remote radio unit (RRU and a baseband unit (BBU) and facilitates communication between a wireless terminal and a core network. The RRU receives a radio frequency signal from a wireless terminal and convert the radio frequency signal to digital baseband samples using receiver circuitry and an analog-to-digital converter. The RRU then adaptively compresses the digital baseband samples, using adaptive compression circuitry, to create fronthaul uplink information, and sends the fronthaul uplink information over a fronthaul link to the BBU using an adaptive fronthaul protocol. The RRU also receives fronthaul downlink information over a fronthaul link from the BBU using an adaptive fronthaul protocol and generates frequency-domain samples, based on the fronthaul downlink information received. It then creates time-domain baseband samples from the frequency-domain samples and converts the time-domain baseband samples into a radio frequency signal to send to the wireless terminal.