An EMC test system (1) and an EMC test method performed in the EMC test system (1) for testing a DUT (6), wherein the EMC test system (1) comprises an EMC test chamber (2), wherein the DUT (6) is positioned in the EMC test chamber (2), at least one measurement equipment (4) positioned in the EMC test chamber (2) and communication means (3) using LiFi for transmitting and receiving measurement data and/or control data by the measurement equipment (4).

An underwater communication method includes creating an air column in a water body using a device including a device body, an air column-generating component, and a transceiver, thereby forming an air column to a surface of the water body. A signal is transmitted, received, or a combination of transmitted and received using the transceiver through the air column to the surface of the water body.

When a frequency deviation compensation amount is compensated for by use of frequency shift, a phase offset occurs between adjacent input blocks included in a plurality of input blocks as divided, with the result that an error occurs in a reconstructed bit sequence. A frequency deviation compensation system of the invention is characterized by comprising: a frequency deviation compensation means for compensating for a frequency deviation occurring in a signal by use of frequency shift; and a phase offset compensation means for compensating for a phase offset occurring, in the signal, due to the frequency shift.

Examples of a three-dimensional (3D) optical sensing system for a vehicle include a modular architecture. Light can be transmitted to an optical signal processing module, which can include a photonic integrated circuit (PIC) that can create one or more signals with tailored amplitude, phase, and spectral characteristics. The plurality of optical signals processed by the optical signal processing module can be sent to beam steering units distributed around the vehicle. The steering units can direct a plurality of optical beams towards targets. The return optical signal can be detected by a receiver PIC including an array of sensors and using a direct intensity detection technique or a coherent detection technique. The return optical signal can be converted into an electrical signal by the array of sensors, which can then be processed by the electronic signal processing unit, and information about the location and speed of the targets can be quantified.

Signal distribution arrangements are assembled by selecting a terminal body and a tap module combination that provides the desired signal strength at the intended position in an optical network. Each terminal body includes an input connection interface, a pass-through connection interface, a module connection interface, and multiple drop connection interfaces. Each tap module houses an optical tap having an asymmetric split ratio. Most of the optical signal power received at the signal distribution arrangement passes to the pass-through connection interface. A portion of the optical signal power is routed to the drop connection interfaces (e.g., via a symmetrical optical power splitter). The tap module and terminal body combination are selected based on the desired number of drop connection interfaces and to balance the asymmetric split ratio with the symmetric split ratio.

Various embodiments of a monolithic transceiver are described, which may be fabricated on a semiconductor substrate. The monolithic transceiver includes a coherent receiver module (CRM), a coherent transmitter module (CTM), and a local oscillation splitter to feed a local oscillation to the CRM and the CTM with a tunable power ratio. The monolithic transceiver provides tunable responsivity by employing photodiodes for opto-electrical conversion. The monolithic transceiver also employs a polarization beam rotator-splitter (PBRS) and a polarization beam rotator-combiner (PBRC) for supporting modulation schemes including polarization multiplexed quadrature amplitude modulation (PM-QAM) and polarization multiplexed quadrature phase shift keying (PM-QPSK).

The present disclosure describes active optical cable assemblies. A cable assembly includes a fixed active optical connector having a transceiver, a ruggedized optical fiber cable integrated with the fixed active optical connector, a main cable assembly comprising one or more optical fiber cables, wherein the ruggedized cable is spliced to the main cable assembly; and a removable shroud configured to surround at least a portion of the fixed active optical connector plugged into a remote radio unit and to be secured to a remote radio unit. Active optical cable and remote radio unit systems are also described.

Cyclic prefix (CP) detection and removal in a wireless communications system (WCS) is disclosed. More specifically, embodiments disclosed herein relate to removing a CP(s) from a random-access symbol(s) in an open radio access network (O-RAN) communications system in the WCS. The random-access symbol(s) includes the CP followed by a random-access sequence. As such, the CP must be removed before the random-access sequence can be detected and processed. In this regard, in embodiments disclosed herein, the O-RAN communications system is configured to determine a group delay associated with the random-access symbol(s) to thereby accurately determine a start of the CP in the random-access symbol(s). Accordingly, the O-RAN communications system can detect and remove the CP from the random-access symbol(s) based on the determined start of the CP. As a result, it is possible to preserve integrity of the random-access symbol(s) to thereby reduce random-access latency in the WCS.

A quantum key distribution device is provided with an encoding unit which encodes an optical pulse train; an intensity modulating unit which subjects the encoded optical pulse train to N (where N is an integer at least equal to 3) types of intensity modulation having mutually different intensities, with different timings; and a first key distillation processing unit which generates an encryption key on the basis of a data sequence obtained by removing data obtained from an optical pulse having a specific modulation pattern from a data sequence used by the encoding unit and the intensity modulating unit.

The invention presents an equalizing device, a corresponding method and an optical signal with a frame structure for enabling the method. The equalizing device includes a first 2×2 MIMO equalizer configured to perform a first equalization on the digital signal, supported by a 2×2 MIMO channel estimation of the channel based on the digital signal. Further, the device includes a second 2×2 MIMO equalizer, arranged after the first equalizer and configured to perform a second equalization on the digital signal, supported by a State of Polarization (SOP) estimation of the optical signal based on the digital signal.