An example of a channelizer includes a plurality of receiver circuits, an individual receiver circuit including a frequency demultiplexer that is configured to demultiplex a plurality of subchannels and a time-division demultiplexer coupled to the frequency demultiplexer, the time-division demultiplexer configured to time-division demultiplex the plurality of subchannels to provide a plurality of time-division outputs, an individual time-division output including portions of data from each of the plurality of subchannels; and a plurality of switch circuits, each configured to receive a different time-division output of the plurality of time-division outputs from the individual receiver.

Methods and systems for reach extension of multi-carrier channels using unequal subcarrier spacing may decrease FWM by grouping the subcarriers into groups of 2 subcarriers, and apply a secondary, unequal spacing between the groups. In this manner, nonlinear interactions may be reduced and the transmission reach of a multi-carrier channel may be extended.

A radio transceiver circuit for FDD communication is disclosed. It comprises a transmitter for FDD signal transmission in a first frequency band, a first receiver for FDD signal reception in a second frequency band, separate from the first frequency band, and a duplexer. An output port of the transmitter is operatively connected to a first port of the duplexer for transmitting, through the duplexer, signals in said first frequency band. An input port of the first receiver is operatively connected to a second port of the duplexer for receiving, through the duplexer, signals in said second frequency band. The radio transceiver circuit comprises a second receiver, separate from the first receiver, for reception in said first frequency band. An input port of the second receiver is operatively connected to said first port of the duplexer for receiving, through the duplexer, signals in said first frequency band. A related radio communication apparatus is also disclosed.

A radio transceiver circuit for FDD communication is disclosed. It comprises a transmitter for FDD signal transmission in a first frequency band, a first receiver for FDD signal reception in a second frequency band, separate from the first frequency band, and a duplexer. An output port of the transmitter is operatively connected to a first port of the duplexer for transmitting, through the duplexer, signals in said first frequency band. An input port of the first receiver is operatively connected to a second port of the duplexer for receiving, through the duplexer, signals in said second frequency band. The radio transceiver circuit comprises a second receiver, separate from the first receiver, for reception in said first frequency band. An input port of the second receiver is operatively connected to said first port of the duplexer for receiving, through the duplexer, signals in said first frequency band. A related radio communication apparatus is also disclosed.

A passive frequency multiplexer includes a beam forming network lens including a plurality of input terminals and a plurality of output terminals; a transmission line for transmitting a signal to the beam forming lens; and a plurality of couplers arranged in series along the transmission line, each of the plurality of couplers comprising an input terminal, an output terminal, and a coupled output terminal, each of the coupled output terminals of the plurality of couplers being coupled to a respective one of the input terminals of the beam forming network lens.

An apparatus and a method. The apparatus includes a channel estimation (CE) module, including a first input for receiving pilot resource element (RE) observations, a second input for receiving data RE observations, a third input for receiving log-likelihood ratios (LLRs), and an output; a detector, including a first input connected to the output of the CE module, a second input for receiving data RE observations, and an output connected to the third input of the CE module; and a decoder, including an input connected to the third input of the CE module, and an output.

An apparatus and a method. The apparatus includes a channel estimation (CE) module, including a first input for receiving pilot resource element (RE) observations, a second input for receiving data RE observations, a third input for receiving log-likelihood ratios (LLRs), and an output; a detector, including a first input connected to the output of the CE module, a second input for receiving data RE observations, and an output connected to the third input of the CE module; and a decoder, including an input connected to the third input of the CE module, and an output.

Embodiments of the present disclosure disclose a method for base station backhaul, a related device and a system for base station backhaul. The method for base station backhaul includes: modulating data carried on at least two channels to corresponding subcarriers respectively, combining and modulating the subcarriers to a first OFDM signal, sending a first broadband OFDM signal to a remote radio unit, sending, by the remote radio unit, the first broadband OFDM signal to an antenna port after splitting and filtering the same; receiving a second broadband OFDM signal sent by the remote radio unit, demodulating subcarriers included in the second broadband OFDM signal, and sending data obtained by demodulating to corresponding channels respectively. By adopting the present disclosure, a utilization rate of a link channel may be improved, and high-capacity base station backhaul may be achieved under a low cost condition.

A method for extracting a plurality of data streams from a time-frequency division multiplexed (TFDM) signal includes determining a plurality of sub-channels of the TFDM signal, where each of the plurality of sub-channels has a respective one of a plurality of frequency ranges. The method also includes down-converting, based on the plurality of frequency ranges, the TFDM signal into a plurality of down-converted signals, where each down-converted signal corresponds to a respective one of the plurality of sub-channels. The method also includes extracting the plurality of data streams from a respective one of the plurality of down-converted signals.

An example system comprises a first antenna and a modem. The first antenna is configured to receive a signal from a transmitting radio frequency unit. The signal includes data and a known sequence. The modem is configured to retrieve the known sequence from the signal, transform the known sequence and the data into a frequency domain, calculate averages of groups of neighboring frequency points in the frequency domain to reduce the effect of nonlinear noise in the signal, the neighboring frequency points corresponding to the preamble in the frequency domain, compare the calculated averages to an expected frequency response in the frequency domain, determine a correction filter to apply to the data based on the comparison, apply the correction filter on the data in the frequency domain to create corrected data, transform the corrected data from the frequency domain to the time domain, and provide the data.