Filter characteristics of a first filter are improved while suppressing degradation in filter characteristics of a second filter. A multiplexer includes a first terminal, a second terminal, a first filter, a second filter, and a capacitive element. The first filter and the second filter are connected to an antenna via the first terminal. The first filter includes a plurality of series arm resonators, a plurality of parallel arm resonators, and an inductor. The inductor is provided between the parallel arm resonator and ground. A first end portion of the capacitive element is connected to a first path at a position in between the series arm resonator that is the closest to the first terminal and the second terminal. A second end portion of the capacitive element is connected between the parallel arm resonator and the inductor.

A method for receiving a modulated signal, includes the steps of receiving a signal modulated by a pulse position modulation (PPM) or a pulse width modulation (PWM) or a pulse amplitude modulation (PAM) or an on-off keying (OOK) amplitude modulation, corresponding to the transmission of a sequence of one or more consecutive digital symbols, squaring the received signal, projecting the square of the received signal onto multiple components of an analogue signal basis in order to obtain an analogue vector of dimension equal to the number of projection components, the components of the analogue signal basis being non-constant functions, digitizing the analogue vector into a digital vector, jointly demodulating the components of the digital vector by way of a maximum likelihood algorithm in order to estimate the transmitted sequence of one or more consecutive digital symbols.

A decentralized communication device is provided that facilitates optimal positioning and orientation of one or more antennas for wireless communication with external devices. The decentralized communication device includes one or more master components and one or more slave components. The master and the slave components are physically separate and communicate wirelessly. In some embodiments the slave acts as a carrier frequency translator between the master and an external wireless device, where it communicates with the external device using a first frequency and communicates with the master using a second frequency which is different from the first frequency. In another embodiment the slave has most or all the physical layer to do the digital coding, digital modulation, data framing, data formatting and data packetization for communicating with an external device, in which case digital coding and digital modulation is distributed between the master and the slave.

A method for tuning an analog front end response is provided. The method includes determining a peaking control value for an analog front end (AFE) of a receiver, determining an attribute corresponding to the peaking control value, selecting the peaking control value as the operating peaking control value for the AFE based on the attribute being determined to be higher than a previous attribute, and performing a receiver adaptation using the peaking control for a one or more transmitter configurations.

An apparatus for processing an input signal from a memory includes an attenuator circuit and an analog front end (AFE) circuit. The attenuator circuit attenuates the input signal from the memory to produce an attenuated signal. The AFE circuit includes a first amplification stage and a second amplification stage. The first amplification stage has an n-type metal-oxide semiconductor (NMOS) transistor. The NMOS transistor has a gate that receives the attenuated signal from the attenuator circuit. The second amplification stage has a p-type metal-oxide semiconductor (PMOS) transistor. The PMOS transistor has a gate that receives the attenuated signal from the attenuator circuit. Outputs of the first amplification stage and the second amplification stage are electrically coupled to a common output of the AFE circuit.

A data link (101) for a MIMO communication system (100) comprises a first transceiver device (106A) comprising a body (109A) having a transducer mounting surface near or at which is mounted a plurality of first transducers (107A-107D) configured to, in use, receive and convert a plurality of electrical waveforms to a respective plurality of acoustic signals. A first bonding layer (120A) bonds a barrier mounting surface of the body of the first transceiver device to a barrier (103). The data link further comprises a second transceiver device (106B) comprising a body (109B) and a plurality of second transducers (107′A-107′D) configured to receive and convert the plurality of acoustic signals transmitted through the barrier to a respective plurality of electrical waveforms. A second bonding layer (120B) bonds a barrier mounting surface of the body of the second transceiver to the barrier.

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 cellular radio architecture that includes a multiplexer coupled to an antenna structure and including multiple signal paths, where each signal path includes a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the multiplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The delta-sigma modulator includes an LC filter having a plurality of LC resonator circuits, a plurality of transconductance amplifiers and a plurality of integrator circuits, where a combination of one resonator circuit, transconductance amplifier and integrator circuit represents a two-order stage of the LC filter.

In one aspect, a method includes: determining a power mode of a device; setting a first reference voltage level and a second reference voltage level based at least in part on the power mode; and using at least one of the first reference voltage level and the second reference voltage level for comparison against incoming data.

A wireless transceiver contains a receiver and a transmitter. The receiver is operable in single-input single-output (SISO) mode as well as multiple-input multiple-output (MIMO) mode, and contains a pair of in-phase and quadrature signal processing chains and a baseband processor. In SISO mode, each of the processing chains in the pair is connected to receive a same modulated signal as input, and generates respective baseband outputs. The baseband processor processes the baseband outputs to demodulate the modulated signal. In MIMO mode, the signal processing chains in the pair receive different modulated signals and generate corresponding down-converted signals. The baseband processor processes the down-converted signals to demodulate the respective modulated signals received by the receiver. Corresponding techniques to provide MIMO in addition to SISO capabilities are implemented in the transmitter also. MIMO capability is thereby achieved in the wireless transceiver with minimal additional implementation area.