Frequency independent isolation of duplexed ports in distributed antenna systems (DASs) is disclosed. Instead of providing a duplexer in a DAS that provides frequency dependent separation between downlink and uplink communications signals, an isolation circuit is provided. The isolation circuit is coupled to a duplexed port that provides downlink communications signals to the DAS and receives uplink communications signals from the DAS. To isolate uplink communications signals from the downlink communications path, the isolation circuit includes a directional coupler. The directional coupler provides frequency independent isolation between uplink communications signals and a downlink communications path in the DAS. Further, to isolate downlink communications signals from the uplink communications path, the isolation circuit includes at least one circulator isolator. The circulator(s) acts as a one-direction device, allowing uplink communications signals to flow to the directional coupler with minimal attenuation while significantly attenuating downlink communications signals flowing from the directional coupler.

Radio frequency (RF) communication circuitry comprises an RF transceiver and conflict detection circuitry. The RF transceiver includes a first communication path configured to down-convert received RF signals using a first local oscillator (LO) receive frequency; and a second communication path configured to down-convert received RF signals using a second LO receive frequency and to operate simultaneously with the first communication path. The conflict detection circuitry is configured to determine path crosstalk using the first and second LO receive frequencies and using a first LO transmit frequency used by the first RF transceiver or a second RF transceiver to up-convert electrical signals for RF transmission, and initiate a change of the first LO receive frequency by a first frequency shift value and a change of the second LO receive frequency by a second frequency shift value in response to the path crosstalk.

Radio frequency (RF) communication circuitry comprises an RF transceiver and conflict detection circuitry. The RF transceiver includes a first communication path configured to down-convert received RF signals using a first local oscillator (LO) receive frequency; and a second communication path configured to down-convert received RF signals using a second LO receive frequency and to operate simultaneously with the first communication path. The conflict detection circuitry is configured to determine path crosstalk using the first and second LO receive frequencies and using a first LO transmit frequency used by the first RF transceiver or a second RF transceiver to up-convert electrical signals for RF transmission, and initiate a change of the first LO receive frequency by a first frequency shift value and a change of the second LO receive frequency by a second frequency shift value in response to the path crosstalk.

A transmitter device 16 for transmitting data to a plurality of receiver devices 51, 52, 53, each of which is connected to the transmitter device via at least one respective pair of wires 21, 22, 23, each receiver device being operable to receive signals detected as a change over time in the potential difference across the local ends of each respective pair of wires extending between the receiver device and the transmitter device, the transmitter device being operable to transmit signals onto the wires extending between the transmitter device and the plurality of receiver devices in a plurality of different modes, over a plurality of different channels, the different modes including phantom and differential modes and the different channels including a first set of phantom channels, the transmitter comprising a phantom channel selector 1690 for selecting a second set of one or more phantom channels from the first set, the second set being a proper subset of the first set comprising one or more of the phantom channels of the first set, the selection being made in dependence upon the cross-talk coupling between the phantom channels of the first set and the reception of signals at each of the receivers detected as a change over time in the potential difference across the local ends of the respective pair of wires extending between the respective receiver device and the transmitter device; and a connector 1670 for connecting the selected phantom channels to the transmitter such that the transmitter is able to transmit signals from the transmitter onto the phantom channel or channels of the second set of phantom channels.

A method for transmitting data advantageously reduces cross-talk in high-speed data transmission. The method comprises receiving an input data word, encoding the input data word into a code word, and driving the code word on to an interconnect for transmission. The code word is generating using a balanced coding scheme, and the interconnect is a single-ended, twisted-wire interposer interconnect. A receiver circuit decodes the code word to generate an output data word.

A computing device operating according to a frequency division multiplexed protocol in which communication occurs over a signal formed from a plurality of sub-channels selected from anywhere in a frequency spectrum. A computing device may select sub-channels cognitively by using information about sub-channels previously deemed suitable or unsuitable by that computing device or other computing devices. A described technique for determining sub-channel suitability includes analyzing radio frequency energy in the sub-channel to detect signals generated by another computing device or high noise levels. Information may also be used to cognitively select sub-channels to be analyzed, such as by first selecting for analysis previously-used sub-channels.

A computing device operating according to a frequency division multiplexed protocol in which communication occurs over a signal formed from a plurality of sub-channels selected from anywhere in a frequency spectrum. A computing device may select sub-channels cognitively by using information about sub-channels previously deemed suitable or unsuitable by that computing device or other computing devices. A described technique for determining sub-channel suitability includes analyzing radio frequency energy in the sub-channel to detect signals generated by another computing device or high noise levels. Information may also be used to cognitively select sub-channels to be analyzed, such as by first selecting for analysis previously-used sub-channels.

The invention relates to a bus system for transmitting data between data processing units in a network, by means of a bus that consists of two signal lines. The signals at said bus are analog signals which lie within a plurality of non-overlapping frequency bands assigned to the individual data processing units, and these data processing units use a digital communication protocol to communicate with a signal processor unit that comprises a polyphase filter bank, a D/A Converter and a bus-coupling unit being connected downstream of said bank in order to couple the data signal into the bus in a galvanically-isolated manner. The proposed bus system has a simple design with regard to cabling, allows the use of a Standard communication protocol such as Ethernet for the data processing units, and additionally allows data to be transmitted between all network subscribers simultaneously and without restriction.

The invention relates to a bus system for transmitting data between data processing units in a network, by means of a bus that consists of two signal lines. The signals at said bus are analog signals which lie within a plurality of non-overlapping frequency bands assigned to the individual data processing units, and these data processing units use a digital communication protocol to communicate with a signal processor unit that comprises a polyphase filter bank, a D/A Converter and a bus-coupling unit being connected downstream of said bank in order to couple the data signal into the bus in a galvanically-isolated manner. The proposed bus system has a simple design with regard to cabling, allows the use of a Standard communication protocol such as Ethernet for the data processing units, and additionally allows data to be transmitted between all network subscribers simultaneously and without restriction.

This disclosure is directed towards improved methods for identifying one or more base stations for connection with user equipment. The user equipment may establish a connection with a base stations based on an estimated location of the base station. Additionally, the user equipment may receive an indication from the base station to scan for additional base stations at additional estimated locations. Further, the user equipment may determine one or more connection parameters (e.g., distance from communication hub to user equipment, angle of communication hub relative to user equipment, shadowing at the communication hub, and the like) associated with the base stations within the geographical area. The user equipment may establish connection with base stations that are determined to have the best signal strength based on the connection parameters.