Abstract: A switch for the switching of communications system signals, with m input ports and n output ports, comprising two or more parallel switch matrices, each of size m×n, combined so that each switch matrix contributes to the available output power at each output port. The failure of one of the switch matrices, or one of the transmission paths therein, will therefore result only in a small reduction in the output power at the relevant output port, rather than complete power loss as would be the case for a conventional switch This fault condition can be detected using a power imbalance detection circuit in the switch matrix combiner. Additionally, the fault condition, having been detected by the power imbalance detection circuit, may be temporarily compensated by an automatic level control system.

Abstract: A signal distribution system for distributing signals, such as for outdoor wireless networks, comprises a number of remote hubs, each of which can direct wireless signals to a number of antennas. The antennas are used to provide wireless service to the service users, such as mobile units, within their geographic coverage area. The remote hubs are connected to main hubs, which are usually located centrally. Each main hub can support a number of remote hubs. The main hubs are connected to a number of base stations (again usually located centrally) in a flexible and re-configurable manner using a switch matrix. Some remote hubs may also include switched matrices for a further level of signal routing.

Abstract: The present invention relates to an electrical space switch matrix having m input ports and n output ports, the switch matrix comprising (m.n)/(i.j) switch blocks, each having i input ports and j output ports, where i is less than m and j is less than n; and a plurality of input elements and a plurality of output elements, the plurality of input elements and plurality of output elements being arranged so as to connect the switch blocks to the input and output ports of the switch matrix. In an embodiment of the invention, the input and output elements can be power splitters and power combiners respectively and are arranged so as to include crossover connection paths therebetween, with the result that crossover of connection paths is distributed between the power dividing/combining function and the switching function.

Abstract: A communications system connects one or more BTS hotels with several remote access nodes on a transmission ring. Each operator has one or more separate optical wavelengths. Signal flow around the ring can either be uni-directional or bi-directional. Each optical wavelength (or wavelength pair) contains the wireless signal traffic for all remote nodes in the ring for the operator using that particular wavelength in digital form. At each node, the incoming signals are electrically demultiplexed and appropriate signals for that node are extracted for conversion to RF. These signals are copied rather than cut so that they are also available at following remote antenna nodes, thereby enabling simulcast operation.

Abstract: The present invention allows remote antenna units for radio frequency signal transmission and receipt to operate without the requirement for remote electrical power supplies or for connecting cables that incorporate electrical conductors. According to an aspect of the present invention, an optical communications system employing radio frequency signals comprises a central unit; at least one remote unit having at least one optoelectronic transducer for converting optical data signals to radio frequency signals and converting radio signals to optical signals and at least one antenna to receive and send radio frequency signals; at least one optical fiber data link between the central unit and the remote unit for transmitting optical data signals therebetween; and at least one optical fiber power link between the central unit and the remote unit for providing electrical power at the remote unit.

Abstract: An optical communications network includes a terminal which can simultaneously receive and modulate an optical signal. The terminal includes an optical modulator which is controlled by varying the bias voltage applied to it.

Abstract: An optical communications network includes a terminal which can simultaneously receive and modulate an optical signal. The terminal includes an optical modulator which is controlled by varying the bias voltage applied to it.