An interface device for communicatively coupling a first communication medium and a second communication medium includes a radio frequency (RF) processor and a frequency shifting subsystem. The RF processor is configured to receive a first data signal from the first communication medium and convert the first data signal to a plurality of first internal RF signals having a common center frequency. The frequency shifting subsystem is configured to shift the plurality of first internal RF signals having the common center frequency to respective first external RF signals having different respective center frequencies, for transmission on the second communication medium. The second communication medium may be a coaxial electrical cable.

There is provided an optical network device (30) comprising separate downstream and upstream signal paths (33, 34) disposed between a wavelength division multiplexing unit (16) and a signal splitting element (32, 44, 50), an optical to electrical signal converter (18) disposed in the downstream path and an electrical to optical signal converter (22) disposed in the upstream path, wherein the signal splitting element (32, 44, 50) is capable of splitting signals independent of signal frequency and is configured with an isolation of 30 to 50 dB thereby to substantially prevent leakage of downstream signals into upstream path (34). The signal splitting element is capable of splitting signals independent of signal frequency and may be a directional coupler, two-way signal splitter or hybrid coupler comprising at least two different types of coupler element.

Provided is a base station signal monitoring system including: a plurality of optical transmission devices configured to transmit a base station signal; a measuring device configured to measure the base station signal according to a preset method; and a switch device, which is connected to the plurality of optical transmission devices and the measuring device, configured to switch connections between a plurality of input ports and a plurality of output ports so that the base station signal is transmitted from one of the plurality of optical transmission devices to the other one of the plurality of optical transmission devices or the measuring device.

An accommodation station transmission unit modulates light to generate an optical signal based on an RF signal and outputs the generated optical signal, a base station transmission unit obtains the optical signal from an input port, demultiplexes the obtained optical signal for each wavelength, outputs the demultiplexed optical signals from output ports of corresponding wavelengths from among a plurality of output ports allocated to each of the wavelengths of the light, and demodulates the RF signal by converting the optical signals output by the output ports into electrical signals, a plurality of transmission antennas emit the demodulated RF signal, and a reflect array or a transmit array receives the RF signal emitted by each of the transmission antennas and forms a transmission beam in a different direction for each position of the transmission antenna that is a transmission source of the RF signal for each RF signal.

A distributed antenna system comprises: one or more access units configured to receive multiple downlink radio frequency signal sets, and further configured to convert the multiple downlink radio frequency signal sets into multiple downlink optical signal sets; a first wavelength division multiplexing unit configured to multiplex the multiple downlink optical signal sets to generate a first wavelength division multiplexing optical signals; a first wavelength division demultiplexing unit configured to demultiplex the first wavelength division multiplexing optical signals to obtain the multiple downlink optical signal sets; a first optical fiber, coupled between the first wavelength division multiplexing unit and the first wavelength division demultiplexing unit, and configured to transmit the first wavelength division multiplexing optical signal; and multiple first remote units coupled to the first wavelength division multiplexing unit, and configured to convert the multiple downlink optical signal sets into the multiple downlink radio frequency signal sets for transmission.

A distributed antenna system comprises a first access unit and a remote unit, wherein the first access unit and the remote unit are coupled via an analog optical fiber, and the first access unit comprises: a first port configured to receive a first downlink analog radio frequency signal; a first analog-to-digital conversion unit configured to perform analog-to-digital conversion on the first downlink analog radio frequency signal to generate a first downlink digital signal; a first digital processing unit configured to perform digital signal processing on the first downlink digital signal to generate a second downlink digital signal; a first digital-to-analog conversion unit configured to perform digital-to-analog conversion on the second downlink digital signal to generate a second downlink analog radio frequency signal; and an analog optical module configured to perform electro-optical conversion on the second downlink analog radio frequency signal to generate a first downlink analog optical signal.

An accommodation station transmission unit modulates light based on an RF signal to generate an optical signal and outputs the generated optical signal, a base station transmission unit demultiplexes the output optical signal for each of wavelengths, outputs the demultiplexed optical signals, converts the demultiplexed optical signals into electrical signals to demodulate the RF signal, outputs the demodulated RF signal, and each of first ports of a matrix operation unit including the plurality of first ports and a plurality of second ports and configured to use each of the first ports as a reference port and perform, on signals obtained by the reference ports, a BFN matrix operation of performing phase changes that are different for each of positions of the reference ports and cause each of phases of signals output from the plurality of second ports to have a linear inclination receives the demodulated RF signal and forms transmission beams in different directions for each of wavelengths by a plurality of transmission antennas emitting the RF signal output by each of the second ports of the matrix operation unit.

Intelligent thermal and power management in a wireless communications device in a wireless communications system (WCS) is disclosed. In a non-limiting example, the wireless communications device can be a base station (e.g., eNB) in the WCS. The wireless communications device includes a number of sensor circuits each configured to perform a sensory measurement (e.g., temperature measurement) in a specific circuit or at a specific location of the wireless communications device. A control circuit is provided in the wireless communications device support intelligent thermal and power management in the wireless communications device. Specifically, the control circuit determines that the sensory measurement is above an abnormal threshold(s) and performs one or more corrective actions accordingly to reduce the sensory measurement to a desirable threshold. By employing intelligent thermal and power management in the wireless communications device, it is possible to improve performance and reduce size of the wireless communications device.

Dynamic radio frequency (RF) beam pattern adaptation in a wireless communications system (WCS) is provided. The WCS typically includes a number of wireless devices, such as remote units and/or base stations, for enabling indoor wireless communications to user devices. The wireless devices are typically mounted on a fixed structure. Notably, a wireless device may be preconfigured to support RF beamforming based on an RF beam pattern that corresponds to a configured orientation. However, the wireless device can be installed with a different orientation from the configured orientation, thus requiring the RF beam pattern to be adapted accordingly. In this regard, a wireless device is configured to dynamically determine an actual orientation of the wireless device and automatically adapt the RF beam pattern based on the determined actual orientation. As a result, it is possible to reduce installation and calibration time associated with deployment of the wireless device in the WCS.

Communication systems and methods over direct current (DC) power conductors to remote subunits may include interrupt windows in a power signal on a DC power conductor for safety reasons. The timing of rising and falling edges of the interrupt window may be modified, thereby changing the duration, period, or position within a period of the interrupt window. In effect, interrupt windows within the DC power signal may be pulse width modulated to send data between a power source and one or more subunits. Pulse width modulation (PWM) of the DC power signal preserves the safety features, but allows data and/or commands to be transferred between the power source and any subunits.