A unified mud-pulse (MP)-electromagnetic (EM) telemetry assembly and a downhole telemetry tool are provided including a downhole EM telemetry transmitter apparatus. The EM telemetry transmitter apparatus comprises a modulator configured to transmit at least one EM signal through transmission medium. The modulator comprises a first reactive circuit and a second reactive circuit, and a plurality of switches controlled by a controller to alternatingly switch the modulator between a first configuration and a second configuration. The EM signals are transmitted by passing one of the reactive circuits and bypassing the other reactive circuit.

Disclosed is a relay method including: receiving, as input, respective reception signals by two receive antennas, the reception signals each including a reception signal resulting from multiplexing respective transmission signals transmitted by two transmission antennas in a first frequency band; performing frequency conversion on the reception signal received by one of the receive antennas so as to obtain a signal of a third frequency band; and performing frequency multiplexing on the signal having the third frequency band and the reception signal received by the other of the receive antennas.

Disclosed is a relay method including: receiving, as input, respective reception signals by two receive antennas, the reception signals each including a reception signal resulting from multiplexing respective transmission signals transmitted by two transmission antennas in a first frequency band; performing frequency conversion on the reception signal received by one of the receive antennas so as to obtain a signal of a third frequency band; and performing frequency multiplexing on the signal having the third frequency band and the reception signal received by the other of the receive antennas.

A polar encoder comprises an input, an output and a processor operatively connected to the input and to the output. The input either receives first, second and third codewords, or receives information bits used by the processor for generating first, second and third probabilistic constellation shaping codewords. The processor combines the first and second codewords, to produce a first modulation symbol bit, combines the first and third codewords to produce a second modulation symbol bit, and combines the first, second and third codewords to produce a third modulation symbol bit. The output forwards the modulation symbol bits to a bit to symbol mapper. The polar encoder may be included in a transmitter that further comprises the bit to symbol mapper receiving the modulation symbol bits and generating modulation symbols, and a modulator modulating a carrier using the modulation symbols.

A polar encoder comprises an input, an output and a processor operatively connected to the input and to the output. The input either receives first, second and third codewords, or receives information bits used by the processor for generating first, second and third probabilistic constellation shaping codewords. The processor combines the first and second codewords, to produce a first modulation symbol bit, combines the first and third codewords to produce a second modulation symbol bit, and combines the first, second and third codewords to produce a third modulation symbol bit. The output forwards the modulation symbol bits to a bit to symbol mapper. The polar encoder may be included in a transmitter that further comprises the bit to symbol mapper receiving the modulation symbol bits and generating modulation symbols, and a modulator modulating a carrier using the modulation symbols.

A transmitting apparatus is disclosed. The transmitting apparatus includes an encoder to perform channel encoding with respect to bits and generate a codeword, an interleaver to interleave the codeword, and a modulator to map the interleaved codeword onto a non-uniform constellation according to a modulation scheme, and the constellation may include constellation points defined based on various tables according to the modulation scheme.

Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

Among other things, a communication system comprising at least one remote unit and controller is described. The at least one remote unit wirelessly exchanges radio frequency (RF) signals with mobile devices. Each RF signal comprises information destined for, or originating from, at least one of the mobile devices. The at least two remote units and the controller communicate baseband data corresponding to the information across an intermediate network. The at least two remote units each implement at least some physical layer processing for an air interface used to wirelessly communicate with the subscriber devices. The controller is configured to perform at least some receive signal processing using combined data resulting from combining at least some of the baseband data communicated from more than one of the at least two remote units.

Among other things, a communication system comprising at least one remote unit and controller is described. The at least one remote unit wirelessly exchanges radio frequency (RF) signals with mobile devices. Each RF signal comprises information destined for, or originating from, at least one of the mobile devices. The at least two remote units and the controller communicate baseband data corresponding to the information across an intermediate network. The at least two remote units each implement at least some physical layer processing for an air interface used to wirelessly communicate with the subscriber devices. The controller is configured to perform at least some receive signal processing using combined data resulting from combining at least some of the baseband data communicated from more than one of the at least two remote units.

A baseband chip may include a transmitter configured to transmit a first signal. The baseband chip may also include a receiver configured to receive a second signal that includes a receive signal portion and a harmonic interference portion leaked from the transmitter. The baseband chip may further include a harmonic model block configured to multiply a first output from a first harmonic model associated with an amplitude modulation phase modulation (AMPM) look-up table (LUT) and a second output of a second harmonic model associated with an AMAM LUT to generate a third output. The harmonic model block may be further configured to estimate the harmonic interference portion based at least in part on the third output. The baseband chip may also include an interference cancellation block configured to cancel the harmonic interference portion from the second signal to obtain the receive signal portion.