There is provided a test apparatus that measures transmission characteristics or reception characteristics of a DUT having an antenna under test, and includes an anechoic box, a posture changeable mechanism 56, a first test antenna 6a and a second test antenna 6b, for measuring the transmission characteristics or the reception characteristics of the DUT, a reflector that reflects a radio signal radiated by the first test antenna and converts the radio signal into a plane wave radio signal, and a movable antenna mechanism 60 that moves a position of the second test antenna such that the radio signal is transmitted to or received from the DUT installed in a far field at a plurality of angles of arrival, with reference to a radio-wave arrival direction from the first test antenna.

Mismatch detection using periodic structures is provided. Embodiments described herein can measure and detect mismatch between two loads in a radio frequency (RF) system without the need for external calibration by referencing their measurements into a small set of parameters that are intrinsic to the RF system design. This approach can be used to compare impedances of two loads and measure their impedances relative to each other without requiring any external calibration (e.g., the approach does not assume any prior known physical quantities in the system, such as a reference impedance). This approach can be used to compare the two loads to each other, as well as to quantify the amount of mismatch between these loads by calculating reflection coefficient between the loads. Loads can be passive devices, such as antennas, or they can be active devices, such as amplifiers.

An optical sender is disclosed, which alone makes it possible to reliably decide whether modulation timing is correct or incorrect and to adjust the modulation timing. The optical sender includes: a first modulator that outputs a first optical pulse train subjected to intensity modulation; an asymmetric interferometer that outputs a second optical pulse train of double pulses; a second modulator (104) that outputs a third optical pulse train subjected to send-data modulation for each pulse pair; nd an optical intensity measuring device that measures an optical intensity of the third optical pulse train, a controller, when changing either of a first optical pulse train according to intensity modulation pattern and a second optical pulse train according to send-data modulation pattern, decides whether the modulation timing is correct or incorrect, based on optical intensity of the third optical pulse train.

A method and a controller for controlling a transmitting node in a wireless telecommunications network, the wireless telecommunications network including a receiving node, wherein the transmitting node includes a plurality of antenna ports, the method including determining a count of antenna ports, being one or more of the transmitting node's plurality of antenna ports, to use in communications with the receiving node based on: a balance between a first performance metric related to a coherence interval and having a positive relationship with the count of antenna ports and a second performance metric related to the coherence interval and having a negative relationship with the count of antenna ports, and/or a measure of the coherence interval in communications with the receiving node; and causing the transmitting node to use the count of antenna ports in communications with the receiving node.

Apparatus and methods are provided for determining AR filter coefficient and numbers of synchronization. In one novel aspect, the AR filter coefficient and times of synchronization are determined based on the temperatures of the oscillator. In one embodiment, the UE determines a temperature drift rate by collecting sets of temperatures before and after the UE in the sleep mode of the CDRX, generates one or more threshold look-up tables and performs an optimization selection based on the temperature drift rate and the one or more threshold of look-up tables, wherein the optimization selection comprising selecting an alpha coefficient and a number of subframes for synchronization. In another embodiment, the optimization selection is further determined based on a subcarrier spacing, and a channel type of being a static channel type and a fading channel type. The UE further performs an on-the-fly oscillator S-curve calibration based on the set of temperatures.

A measurement device is provided. Said measurement device comprises a plurality of ports for receiving and/or transmitting radio frequency signals, a plurality of measurement units with one measurement unit for each of the plurality of ports, each measurement unit being configured to measure the corresponding forward and/or reverse radio frequency signal, and a subset of additional measurement units, preferably one additional measurement unit, configured to be connected to a subset, preferably one, of the ports in addition to or instead of the respective at least one of the plurality of measurement units.

Apparatus comprising: one or more processors, and memory storing instructions that, when executed by the one or more processors, cause the apparatus to perform: monitoring whether a terminal suffers a performance issue due to an artificial intelligence/machine learning operation performed by the terminal; performing an action related to the artificial intelligence/machine learning operation to remove or reduce the performance issue if the terminal suffers the performance issue due to the artificial intelligence/machine learning operation.

A method for determining a nonlinearity characteristic of a receiver path includes generating a set of N?M digital samples by repeating N times selecting an scaling factor from a set of N scaling factors, generating a version of a test signal, the version of the test signal corresponding to a test signal scaled by the respective scaling factor, processing the respective version of the test signal in at least a part of the receiver path to generate a respective processed signal, and storing M digital samples corresponding to the respective processed signal. Fourier-transformed data are generated using at least a portion of the set of N?M digital samples and a nonlinearity characteristic of the receiver path is determined based on the Fourier-transformed data.

The invention relates to a measurement system, including a signal analyzer or monitoring receiver, for measuring and analyzing modulated signals. The system includes a signal acquisition device having input port(s), wherein the signal acquisition device is configured to capture modulated signal(s) applied to the input ports, wherein each captured modulated signal can be represented as an I/Q signal; wherein the signal acquisition device generates at least two digital I/Q data streams based on the one or more modulated signals, wherein the at least two digital I/Q data streams are generated in parallel. The measurement system includes a selection device to select at least one target frequency bandwidth in each of the at least two digital I/Q data streams; and a signal processing device configured to analyze the at least two digital I/Q data streams in the selected target frequency bandwidths.

Mismatch detection using periodic structures is provided. Embodiments described herein can measure and detect mismatch between two loads in a radio frequency (RF) system without the need for external calibration by referencing their measurements into a small set of parameters that are intrinsic to the RF system design. This approach can be used to compare impedances of two loads and measure their impedances relative to each other without requiring any external calibration (e.g., the approach does not assume any prior known physical quantities in the system, such as a reference impedance). This approach can be used to compare the two loads to each other, as well as to quantify the amount of mismatch between these loads by calculating reflection coefficient between the loads. Loads can be passive devices, such as antennas, or they can be active devices, such as amplifiers.