Technologies for provided for a radio frequency input/output (RFIO) combiner/splitter. An example combiner/splitter can include an RFIO circuit including a receive path including first and second low noise amplifiers (LNAs), first switches, resistors, and capacitors, each of the first switches being in series with a respective one of the first capacitors and first resistors;

a transmit path including a first power amplifier (PA) including second switches coupled to second resistors and third switches coupled to third resistors, and a second PA including fourth switches coupled to fourth resistors and fifth switches coupled to fifth resistors, each of the second switches, the third switches, the fourth switches, and the fifth switches being in series with one or more respective ones of the second resistors, the third resistors, the fourth resistors, and the fifth resistors; and a balun that couples the Rx and Tx path to an RFIO terminal.

An apparatus, method and computer program product is disclosed. The apparatus may comprise means for transmitting and receiving radio frequency signals using a radio system coupled to an external antenna via an additional combiner or diplexer, means for receiving one or more reference signals usable for measurement of passive intermodulation from one or more nodes provided in a signal path external to the radio system, a first one of said nodes being associated with a signal path between the additional combiner or diplexer and the external antenna, and means for performing passive intermodulation cancellation based on the received one or more reference signals, including a first reference signal from the first node.

Provided is an OFDM reception apparatus that can reduce, even in an environment where the influence of noises is strong, this influence of the noises, thereby improving the precision of detecting a carrier frequency error. In this apparatus, a filtering unit (151) receives received signals each including a short preamble (STF) in which a plurality of pilot subcarriers are intermittently arranged in the frequency domain and repeatedly arranged in the time domain, and the filtering unit (151) attenuates the frequency components between respective two adjacent ones of the plurality of pilot subcarriers in the frequency domain. A correction unit (154) corrects a carrier frequency error of the received signal on the basis of the signals of the plurality of pilot subcarriers having passed through the filtering unit (151).

A method and an apparatus relating to an OFDM data communications system where the sub-carriers are modulated using differential quadrature phase-shift keying (DQPSK). The multi-carrier transmitted signal is directly generated by means of summation of pre-computed sample points. As part of the multi-carrier signal generation, a signal for the guard interval is established. In an acoustic application of this approach, direct radiation of the sub-carrier approach is facilitated. Symbol synchronization in the receiver is based on signal correlation with the missed sub-carrier. Separation of the sub-carriers in the receiver by means of correlation of the received signal and reference signals that are derived from a table of pre-computed values. Optimal non-coherent processing of the sub-carriers without any phase tracking procedures is achieved.

Embodiments of the present disclosure provide a multipath time delay estimation apparatus and method and a receiver. Time delay is divided into at least two subzones according to cross-correlation values of the transmission signal and the received signal, and time delay estimation is performed on each path in each subzone respectively, thereby efficiently improving resolution of the time delay estimation. And in performing time delay estimation on each path in each subzone, cross-correlation values of other subzones are set to be predefined values, so as to lower influence of strong paths of other subzones on the time delay estimation on each path in the current subzone, thereby efficiently improving accuracy of time delay estimation of weak paths.

A circuit includes a radio frequency (RF) channel including an input node and an output node and being configured to receive an RF oscillator signal at the input node and to provide an RF output signal at the output node; a mixer configured to mix an RF reference signal and an RF test signal representative of the RF output signal to generate a mixer output signal; an analog-to-digital converter configured to sample the mixer output signal in order to provide a sequence of sampled values; and a control circuit configured to provide a sequence of phase offsets by phase-shifting at least one of the RF test signal and the RF reference signal using one or more phase shifters, calculate a spectral value from the sequence of sampled values; and calculate estimated phase information indicating a phase of the RF output signal based on the spectral value.

A PIM cancellation apparatus includes: a first obtaining unit, configured to obtain digital signals of N transmit channels; a second obtaining unit, configured to obtain receive signals; and a PIM simulation unit, configured to obtain N PIM cancellation signals based on the digital signals of the N transmit channels, where the PIM simulation unit includes a first linear module performing first filtering and first linear superposition on the digital signals of the N transmit channels to obtain a first linear superposition result, a non-linear module performing non-linear processing on the first linear superposition result to obtain a non-linear processing result, and each filter in a second linear module performing linear processing on each corresponding non-linear processing result to determine one PIM cancellation signal, to obtain the N PIM cancellation signals; and a cancellation unit, configured to obtain N cancellation result signals.

An electronic device may be provided with wireless circuitry. The wireless circuitry may include one or more antennas. The antennas may include phased antenna arrays each of which includes multiple antenna elements. Phased antenna arrays may be mounted along edges of a housing for the electronic device, behind a dielectric window such as a dielectric logo window in the housing, in alignment with dielectric housing portions at corners of the housing, or elsewhere in the electronic device. A phased antenna array may include arrays of patch antenna elements on dielectric layers separated by a ground layer. A baseband processor may distribute wireless signals to the phased antenna arrays at intermediate frequencies over intermediate frequency signal paths. Transceiver circuits at the phased antenna arrays may include upconverters and downconverters coupled to the intermediate frequency signal paths.

A data processing device includes a restoration unit that performs a conversion operation on an input signal to convert the input signal into a signal having no distortion caused by an external factor, and a selection unit that selects and outputs either an unrestored signal, which is the input signal, or a restored signal, which is a signal obtained by the restoration unit by performing the conversion operation, based on a feature quantity of the unrestored signal and on a feature quantity of the restored signal.

A network access device placed between one or more distribution devices and multiple premises may remotely or wirelessly monitor and/or analyze signal characteristics at the network access device and or of equipment at the multiple premises. The network access device may adjust switchably-filtered signal paths between the distribution device(s) and the multiple premises to remove or mitigate signal interference.