The disclosed embodiments provide an absorptive coupled-line bandpass filter. This bandpass filter includes a first port, which is coupled to a first absorptive stub, and a second port, which is coupled to a second absorptive stub. The bandpass filter also includes a coupled-line bandpass section coupled between the first and second ports, wherein the coupled-line bandpass section comprises a set of one or more parallel strip line resonators, which are coupled together in series and are coupled to the first and second ports through overlapping coupled-line sections, wherein at a center frequency of a passband for the absorptive coupled-line bandpass filter, the first and second absorptive stubs appear as open circuits, and outside of the passband, the first and second absorptive stubs appear as matched loads to ground and contribute to absorption of out-of-band signals.

A method for operating a radio frequency communications system includes, while operating a first radio frequency communications device in a calibration mode, for each setting of a plurality of settings of a programmable gain amplifier in a receiver of the first radio frequency communications device configured in a zero-intermediate frequency mode of operation, generating an estimate of a DC offset in each of a plurality of digital samples received from an analog circuit path including the programmable gain amplifier, and storing in a corresponding storage element, a compensation value based on the estimate.

A method for operating a radio frequency communications system includes, while operating a first radio frequency communications device in a calibration mode, for each setting of a plurality of settings of a programmable gain amplifier in a receiver of the first radio frequency communications device configured in a zero-intermediate frequency mode of operation, generating an estimate of a DC offset in each of a plurality of digital samples received from an analog circuit path including the programmable gain amplifier, and storing in a corresponding storage element, a compensation value based on the estimate.

Method for processing a sequence of digital signal samples including a first sub-sequence and a second sub-sequence. Forming a first block of samples comprising the first sub-sequence and a second block of samples comprising header samples followed by the second sub-sequence. Demodulating the first block of samples through a digital demodulator to produce a first block of symbols, and the second block of digital signal samples through a second digital demodulator to produce a second block of symbols. The second demodulator implementing a carrier synchronisation or symbol rate synchronisation starting with the header samples, which comprise samples in a number adapted in such a way that the synchronisation is effective before the second demodulator demodulates the second sub-sequence. Reconstructing a sequence of symbols by concatenating the first symbol block with the second symbol block.

Method for processing a sequence of digital signal samples including a first sub-sequence and a second sub-sequence. Forming a first block of samples comprising the first sub-sequence and a second block of samples comprising header samples followed by the second sub-sequence. Demodulating the first block of samples through a digital demodulator to produce a first block of symbols, and the second block of digital signal samples through a second digital demodulator to produce a second block of symbols. The second demodulator implementing a carrier synchronisation or symbol rate synchronisation starting with the header samples, which comprise samples in a number adapted in such a way that the synchronisation is effective before the second demodulator demodulates the second sub-sequence. Reconstructing a sequence of symbols by concatenating the first symbol block with the second symbol block.

A mixer for mixing a radio frequency signal is described. The mixer includes a local oscillator input, a phase adjustment module, and at least one mixing channel. The local oscillator input is configured to receive a local oscillator signal. The phase adjustment module is configured to control a phase of the local oscillator signal in order to add a desired amount of delay to the local oscillator signal, thereby generating at least one adapted oscillator signal. The at least one adapted oscillator signal has a desired phase difference compared to the local oscillator signal. The at least one mixing channel includes at least one mixer unit having at least one signal input. The at least one mixing channel is configured to receive the at least one adapted oscillator signal. The at least one mixing channel further is configured to forward the adapted oscillator signal to the mixer unit. The at least one signal input is configured to receive an input signal. The at least one signal input further is configured to forward the input signal to the mixer unit. The mixer unit is configured to mix the at least one adapted oscillator signal with the input signal, thereby generating a mixer output signal.

This application discloses a radio frequency receiver and a wireless communication apparatus. The radio frequency receiving apparatus includes: a first receiver, including a first receive channel and a second receive channel; a second receiver, including a third receive channel, where both maximum signal bandwidths supported by the first receive channel and the second receive channel are less than a maximum signal bandwidth supported by the third receive channel; an analog-to-digital converter ADC group, including a plurality of ADCs, where the plurality of ADCs includes a first ADC and a second ADC; and a channel router, configured to allocate an ADC.

Systems and method are provided for canceling unwanted transmitter-to-receiver leakage in a coherent wireless system using a feedforward waveform that overcomes the limitations of purely analog or purely digital cancelation systems and methods. Systems and methods in accordance with embodiments of the present disclosure generate a software-defined waveform that, when fed forward into the receiver, effectively cancels the leakage. Embodiments of the present disclosure can use a defined cancelation waveform (e.g., a software-defined cancelation waveform) that can cancel multiple leakage paths at the same time.

Systems and method are provided for canceling unwanted transmitter-to-receiver leakage in a coherent wireless system using a feedforward waveform that overcomes the limitations of purely analog or purely digital cancelation systems and methods. Systems and methods in accordance with embodiments of the present disclosure generate a software-defined waveform that, when fed forward into the receiver, effectively cancels the leakage. Embodiments of the present disclosure can use a defined cancelation waveform (e.g., a software-defined cancelation waveform) that can cancel multiple leakage paths at the same time.

A semiconductor chip includes a first wireless communication circuit, a local oscillator (LO) buffer, and an auxiliary path. The first wireless communication circuit has a signal path, wherein the signal path has a mixer input port and a signal node distinct from the mixer input port. The auxiliary path is used to electrically connect the LO buffer to the signal node of the signal path. The LO buffer is reused for a loop-back test function through the auxiliary path.