A method for wirelessly calibrating/testing RF and digital components of a multi-antenna device under test includes the step of wirelessly transmitting a first signaling information between the device under test and a device tester, the first signaling information indicating a calibration request, wherein the first signaling information is transmitted by the device under test or the device tester. Further, the method includes the step of estimating, in response to the first signaling information, channel transfer function matrices between active antenna ports/RF ports of the device under test and antenna ports of the device tester using reference signals wirelessly transmitted between the device tester and the device under test or vice versa.

Flame-resistant paper for radio wave absorber members includes 40 to 70% by mass of pulp; 5 to 50% by mass of aluminum hydroxide powder; and 3 to 15% by mass of a flame retardant consisting of a polyborate, wherein the flame retardant consisting of a polyborate is contained in an amount of 7 to 25% by mass relative to the amount of the pulp.

Various embodiments are presented of a system including an alignment fixture for testing (e.g., rapidly and cheaply) phased array antennas and other devices configured for radio frequency (RF) transmission and/or reception. A device to be tested (e.g., the device under test (DUT)) may be positioned in a testing position by the alignment fixture. The alignment fixture may provide a configurable level of friction to retain the DUT in the testing position. The alignment fixture may provide isolation from electromagnetic interference for the DUT while in the testing position.

An electromagnetic wave measurement system may include: a reference receiving device; a plurality of auxiliary receiving devices; and a control device connected to the reference receiving device and the plurality of auxiliary receiving devices, wherein the reference receiving device has a wider dynamic range than the plurality of auxiliary receiving devices, the control device collects a frequency-specific measurement value from each of the reference receiving device and the plurality of auxiliary receiving devices, and the frequency-specific measurement value of each of the auxiliary receiving devices is calibrated based on the frequency-specific measurement value of the reference receiving device.

The present invention discloses a test method and arrangement for testing GNSS signals within a test chamber. The test chamber inner walls are supplied with transmitting antennas supplying simulated satellite signals, originating from a signal generator. Dynamic satellite movements are simulated by interpolating several transmitted signals in order to create a single true satellite transmission signal. All visible satellites are taken into account in order to create simulated GPS signals across the whole virtual sky. Phantom objects may be used near the device under test and the phantom object may be moved or rotated in preset patterns within the test chamber. Radio channel information can be modelled according to several different real-life environments, and also reflections from any surfaces and different multipath options are taken into account in the modeling, and also in the transmission antenna angles towards the device under test. Main application areas of the invention comprise sports watches, health related or any other monitoring devices, or any devices benefiting from the positioning information, also relating to animal applications. The device may be carried or worn by the human user or any other living creature, as a wearable positioning device.

A waterproof structure includes a housing and a waterproof button. The housing has a first surface, a first side surface, and a second surface. The first side surface is recessed in the first surface to define a first opening, the first side surface is connected between the first surface and the second surface, and the second surface is exposed from the first opening. The waterproof button is disposed in the first opening and includes at least one first water blocking structure, and the first water blocking structure is pressed and deformed to abut against the first side surface.

Embodiments of the present disclosure provide an antenna assembly for a test system. The antenna assembly includes a feedthrough part, two waveguide inputs, a single waveguide output as well as a multiplexing part that is interconnected between the two waveguide inputs and the single waveguide output. The multiplexing part is integrated within the feedthrough part at least partially. Moreover, embodiments of the present disclosure provide a test system and a method of establishing a test system for testing a device under test.

An over-the-air (OTA) measurement system for testing a device under test, with a plurality of feed antennas, a test location for the device under test, and a reflector array with a main reflector and a sub-reflector. The plurality of feed antennas face the sub-reflector. The reflector array is located such that a signal path is established between the plurality of feed antennas and the test location via the sub-reflector and the main reflector. The sub-reflector has at least one focal point. The plurality of feed antennas include a first feed antenna and at least one second feed antenna. The first feed antenna is associated with the focal point of the sub-reflector. The at least one second feed antenna is located offset from the focal point of the sub-reflector. Further, a method of testing a device under test over-the-air is described.

An electromagnetic wave measurement system may include: a reference receiving device; a plurality of auxiliary receiving devices; and a control device connected to the reference receiving device and the plurality of auxiliary receiving devices, wherein the reference receiving device has a wider dynamic range than the plurality of auxiliary receiving devices, the control device collects a frequency-specific measurement value from each of the reference receiving device and the plurality of auxiliary receiving devices, and the frequency-specific measurement value of each of the auxiliary receiving devices is calibrated based on the frequency-specific measurement value of the reference receiving device.

A measurement system for testing a device under test includes a signal generation and/or analysis equipment, several antennas, several reflectors and a test location for the device under test. The antennas are connected with the signal generation and/or analysis equipment in a signal-transmitting manner Each of the antennas is configured to transmit and/or receive an electromagnetic signal so that a beam path is provided between the respective antenna and the test location. The electromagnetic signal is reflected by the respective reflector so that the electromagnetic signal corresponds to a planar wave. Each antenna and the corresponding reflector together are configured to provide a corresponding quiet zone at the test location. At least one of the quiet zones provided is larger than the at least one other quiet zone and/or at least one of the antennas is configured to operate at a different frequency compared to the at least one other antenna. Further, a method of performing an over-the-air test of a device under test is described.