The disclosure relates to a radio receiver module for receiving a signal having a lower side band and an upper side band, the module comprising: a noise detector configured to identify a noise frequency associated with an unwanted noise signal within the lower or upper side band; a filter configured to attenuate the noise frequency and increase gain at a mirror frequency within the signal in order to provide a filtered signal, wherein the mirror frequency is within the sideband that is unaffected by the unwanted noise signal and the mirror frequency corresponds to the noise frequency.

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 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.

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.

In one example, an apparatus includes: a delay unit to delay a demodulated signal obtained from an input radio frequency (RF) frequency modulation (FM) signal; a filter to filter the demodulated signal and output a filtered demodulated signal; an impulse detection circuit to receive the filtered demodulated signal and detect presence of an impulse in the demodulated signal; and an impulse removal circuit to remove the detected impulse from the demodulated signal.