A radio communication apparatus includes: a first radio frequency subunit, configured to modulate a third analog baseband signal into a third carrier signal, and send the third carrier signal to a first switch; a second radio frequency subunit, configured to modulate a fourth analog baseband signal into a fourth carrier signal, and send the fourth carrier signal to a second switch; the first switch; the second switch; and the first duplexer shared by a first switch and a second switch, configured to receive the third carrier signal from the first switch, receive the fourth carrier signal from the second switch, filter the third carrier signal and the fourth carrier signal to combine the third carrier signal and the fourth carrier signal to obtain a second carrier aggregation signal, and input the second carrier aggregation signal to a first antenna.

The disclosure relates to arrangements for antenna interfaces configurable to efficiently support different communication modes. This is achieved by an antenna connection circuit 10 for a communication device 1 wherein the antenna connection circuit 10 is configurable for communication modes. The antenna connection circuit comprises a first quarter-wave transformer qw1 coupled between an antenna port A and an transmitter port Tx, and a second quarter-wave transformer qw2 coupled between the antenna port A and a receiver port Rx. The antenna connection circuit further comprises a first ground switch s1 coupled between the receiver port Rx and a first ground connection g1, and a second ground switch s2 is coupled between the transmitter port Tx and a second ground connection g2. The antenna connection circuit further comprises a resistor R and a resistor switch s3 coupled in series between the receiver port Rx and the transmitter port Tx, and an inverting amplifier switch s4 coupled between the receiver port Rx and an input port I1 of an inverting amplifier Amp1, and an output port O1 of the inverting amplifier Amp1 is coupled to the transmitter port Tx.

Technology for a low-noise signal chain is disclosed. The low-noise signal chain can include a signal path configured to carry a signal. The low-noise signal chain can include a bypassable amplifier communicatively coupled to the signal path. The low-noise signal chain can include a switchable band pass filter communicatively coupled to the signal path. The low-noise signal chain can include an amplifier bypass path communicatively coupled to the signal path. The signal can be configured to be directed to the amplifier bypass path to bypass the bypassable amplifier. The low-noise signal chain can include a band pass filter bypass path communicatively coupled to the signal path. The signal can be configured to be directed to the band pass filter bypass path to bypass the switchable band pass filter.

Technology for a low-noise signal chain is disclosed. The low-noise signal chain can include a signal path configured to carry a signal. The low-noise signal chain can include a bypassable amplifier communicatively coupled to the signal path. The low-noise signal chain can include a switchable band pass filter communicatively coupled to the signal path. The low-noise signal chain can include an amplifier bypass path communicatively coupled to the signal path. The signal can be configured to be directed to the amplifier bypass path to bypass the bypassable amplifier. The low-noise signal chain can include a band pass filter bypass path communicatively coupled to the signal path. The signal can be configured to be directed to the band pass filter bypass path to bypass the switchable band pass filter.

TX/RX switch circuits include an input, a first circulator having a first port coupled to the input, a circuit element having a first port coupled to a second port of the first circulator, a second circulator having a first port coupled to a second port of the circuit element, an output coupled to a second port of the second circulator, a low noise amplifier coupled between a third port of the second circulator and a third port of the first circulator, a bias circuit that is configured to set an impedance at a third port of the circuit element at a first impedance level when operating in transmit mode and to set the impedance at the third port of the circuit element to have a second impedance level when operating in receive mode, and a first PIN diode coupled between an output of the low noise amplifier and electrical ground.

TX/RX switch circuits include an input, a first circulator having a first port coupled to the input, a circuit element having a first port coupled to a second port of the first circulator, a second circulator having a first port coupled to a second port of the circuit element, an output coupled to a second port of the second circulator, a low noise amplifier coupled between a third port of the second circulator and a third port of the first circulator, a bias circuit that is configured to set an impedance at a third port of the circuit element at a first impedance level when operating in transmit mode and to set the impedance at the third port of the circuit element to have a second impedance level when operating in receive mode, and a first PIN diode coupled between an output of the low noise amplifier and electrical ground.

A transmission filter includes a transmission filter circuit and an additional circuit. The transmission filter circuit defines a first signal path connecting a first terminal and a second terminal. The additional circuit is connected to a first node located between the first terminal and the transmission filter circuit on the first signal path and a second node located between the second terminal and the transmission filter circuit on the first signal path and defines a second signal path connecting the first node and the second node. The additional circuit includes, on the second signal path, a resonator group, a capacitive element, and an inductance element. The inductance element is electromagnetically coupled to the transmission filter circuit.

A base station grants communications of a plurality of wireless communication terminals with the base station without allocating wireless resources upon occurrence of requests for the communications. The base station receives radio signals incoming from the wireless communication terminals and having encoded data, executes a first process of obtaining, from the received radio signals, first signals with at least ones of amplitudes and phases being adjusted, the first signals being incoming from a first wireless communication terminal among the plural wireless communication terminals, a second process of generating replicas of the radio signals incoming from the first wireless communication terminal before at least ones of the amplitudes and the phases are adjusted, a third process of extracting signals given by removing the replicas of the incoming radio signals from the received radio signals, and a process of iterating the first through third processes successively.

A base station grants communications of a plurality of wireless communication terminals with the base station without allocating wireless resources upon occurrence of requests for the communications. The base station receives radio signals incoming from the wireless communication terminals and having encoded data, executes a first process of obtaining, from the received radio signals, first signals with at least ones of amplitudes and phases being adjusted, the first signals being incoming from a first wireless communication terminal among the plural wireless communication terminals, a second process of generating replicas of the radio signals incoming from the first wireless communication terminal before at least ones of the amplitudes and the phases are adjusted, a third process of extracting signals given by removing the replicas of the incoming radio signals from the received radio signals, and a process of iterating the first through third processes successively.

The present disclosure relates to a transceiver comprising a transmitter with transformation circuitry configured to transform a frequency-domain transmit symbol from frequency domain to time domain to generate a time-domain transmit signal, a receiver with inverse transformation circuitry configured to transform a time-domain receive signal from time domain to frequency domain to generate a frequency-domain receive symbol, and self-interference cancellation circuitry configured to modify the frequency-domain receive symbol based on at least one frequency-domain transmit symbol and a frequency-domain crosstalk channel estimate of a crosstalk channel between the transmitter and the receiver.