Abstract: A power amplifier using N-way Doherty structure with adaptive bias supply power tracking for extending the efficiency region over the high peak-to-average power ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.

Abstract: A method of determining a carrier power in a communications system including a processor includes a) setting a power differential between a reference carrier and one or more carriers, b) measuring a number of satisfied users at the power differential, and c) measuring a capacity for the satisfied users at the power differential. The method also includes d) increasing the power differential by a predetermined amount and e) determining, using the processor, that the number of satisfied users at the increased power differential is greater than or equal to the number of satisfied users at the power differential. The method further includes f) repeating a)-c) and g) setting the carrier power at an iterated power level.

Abstract: A method for routing and switching operator RF signals includes providing one or more Digital Remote Units (DRUs) and providing at least one Digital Access Unit (DAU) configured to communicate with at least one of the one or more DRUs. A first DRU is operable to communicate using a first set of frequencies characterized by a first frequency band over a first geographic footprint and a second set of frequencies characterized by a second frequency band different from the first frequency band over a second geographic footprint including and surrounding the first geographic footprint. A second DRU is operable to communicate using the first set of frequencies over a third geographical footprint and a third set of frequencies characterized by a third frequency band different from the first frequency band and the second frequency band over a fourth geographic footprint including and surrounding the third geographic footprint.

Abstract: The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. The present disclosure enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as flexible simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous/assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc.

Abstract: Methods and apparatuses are presented for balancing non-uniformly distributed network traffic in a wireless communications system having a plurality of digital remote units (DRUs). In some embodiments, a method comprises partitioning the plurality of DRUs into a plurality of DRU sectors, and dynamically repartitioning the plurality of DRU sectors depending on traffic conditions in at least one of the DRU sectors, such that the repartitioning satisfies at least one of a soft capacity constraint or a hard capacity constraint. The dynamic repartitioning may be based on at least one optimization algorithm.

Abstract: A digital predistortion linearization method is provided for increasing the instantaneous or operational bandwidth for RF power amplifiers employed in wideband communication systems. Embodiments of the present invention provide a method of increasing DPD linearization bandwidth using a feedback filter integrated into existing digital platforms for multi-channel wideband wireless transmitters. An embodiment of the present invention utilizes a DPD feedback signal in conjunction with a low power band-pass filter in the DPD feedback path.

Abstract: An efficient baseband predistortion linearization method for reducing the spectral regrowth and compensating memory effects in wideband communication systems using effective multiplexing modulation technique such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. The present invention is based on the method of piecewise pre-equalized lookup table based predistortion, which is a cascade of a lookup table predistortion and piecewise pre-equalizers.

Abstract: The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. The present invention enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as Flexible Simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous/assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc. As a result, a DAS in accordance with the present invention can increase the efficiency and traffic capacity of the operators' wireless network.

Abstract: A method for transporting communications signals includes receiving an analog IF signal at a first unit. The analog IF signal includes a first carrier having a first frequency and a first bandwidth and a second carrier having a second frequency different from the first frequency and a second bandwidth. The analog IF signal is converted to a digitally sampled IF signal having the first carrier located in a first Nyquist zone, the second carrier located in a second Nyquist zone, an image of the first carrier located in a third Nyquist zone, and an image of the second carrier located in the third Nyquist zone. The image of the first carrier and the image of the second carrier is transmitted from the first unit to a second unit, where the image of the first carrier and the image of the second carrier is then converted to the analog IF signal.

Abstract: Embodiments may allow remote base transceiver stations (BTSs) physically located away from a local source of users to be able to provide local service as if the remote BTSs were at or near the local source of users. Some embodiments may include a plurality of BTSs, each having one or more sectors, and one or more digital access units (DAUs). Embodiments may also include a plurality of repeater digital units (RDUs), where each RDU may be configured to communicate to at least one of the plurality of BTSs and may be operable to route signals optically to the one or more DAUs. Embodiments may also include a plurality of digital remote units (DRUs) located at a location remote to the one or more DAUs, wherein the plurality of remote DRUs may be operable to transport signals to the one or more DAUs.

Abstract: A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and/or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.

Abstract: A remote radio head unit (RRU) system is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier inside the RRU. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by a wideband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, embodiments of the present invention can compensate for the nonlinearities as well as memory effects of the power amplifier systems and also improve performance, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers, multi-frequency bands and multi-channels.

Abstract: A distributed antenna system includes a master unit including a downlink RF input operable to receive an RF input signal from a downlink port of a base station, a first optical port, and a second optical port. The distributed antenna system also includes a first remote unit coupled to the first optical port. The first remote unit comprises a downlink antenna port and a first uplink antenna port and a second remote unit coupled to the second optical port of the master unit. The second remote unit comprises a downlink antenna port and a second uplink antenna port. The master unit is operable to transmit a first RF signal associated with the first RF uplink signal to a first uplink port of the base station and transmit a second RF signal associated with the second RF uplink signal to a second uplink port of the base station.

Abstract: A method for routing and switching operator RF signals includes providing one or more Digital Remote Units (DRUs) and providing at least one Digital Access Unit (DAU) configured to communicate with at least one of the one or more DRUs. A first DRU is operable to communicate using a first set of frequencies characterized by a first frequency band over a first geographic footprint and a second set of frequencies characterized by a second frequency band different from the first frequency band over a second geographic footprint including and surrounding the first geographic footprint. A second DRU is operable to communicate using the first set of frequencies over a third geographical footprint and a third set of frequencies characterized by a third frequency band different from the first frequency band and the second frequency band over a fourth geographic footprint including and surrounding the third geographic footprint.

Abstract: A digital predistortion linearization method is provided for increasing the instantaneous or operational bandwidth for RF power amplifiers employed in wideband communication systems. Embodiments of the present invention provide a method of increasing DPD linearization bandwidth using a feedback filter integrated into existing digital platforms for multi-channel wideband wireless transmitters. An embodiment of the present invention utilizes a DPD feedback signal in conjunction with a low power band-pass filter in the DPD feedback path.

Abstract: A system for routing signals in a Distributed Antenna System includes a plurality of local Digital Access Units (DAUs) located at a Local location. Each of the plurality of local DAUs is coupled to each other and operable to route signals between the plurality of local DAUs. Each of the plurality of local DAUs includes one or more Base Transceiver Station (BTS) RF connections. Each of the plurality of BTS RF connections is operable to be coupled to one of one or more sectors of a BTS. The system also includes a plurality of remote DAUs located at a Remote location. The plurality of remote DAUs are coupled to each other and operable to transport signals between the plurality of remote DAUs.

Abstract: A power amplifier using N-way Doherty structure with adaptive bias supply power tracking for extending the efficiency region over the high peak-to-average power:ratio of the multiplexing modulated signals such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. In an embodiment, present invention uses a dual-feed distributed structure to an N-way Doherty amplifier to improve the isolation between at least one main amplifier and at least one peaking amplifier and, and also to improve both gain and efficiency performance at high output back-off power. Hybrid couplers can be used at either or both of the input and output. In at least some implementations, circuit space is also conserved due to the integration of amplification, power splitting and combining.

Abstract: A system for routing signals in a Distributed Antenna System (DAS) includes one or more Base Band Units (BBUs). Each of the one or more BBUs has one or more digital outputs. The system also includes a plurality of Digital Multiplexer Units (DMUs) coupled to each other and operable to route signals between the plurality of DMUs. Each of the plurality of DMUs is operable to receive one or more digital inputs from the one or more BBUs. The system further includes a plurality of Digital Remote Units (DRUs) coupled to the plurality of DMUs and operable to transport signals between the plurality of DRUs and one or more of the plurality of DMUs.

Abstract: A system for transporting IP data in a Distributed Antenna System includes at least one Digital Access Units (DAU) having a plurality of optical input/output ports and at least one Ethernet port and a plurality of Digital Remote Units (DRUs) coupled to the at least one DAU. Each of the plurality of DRUs has a plurality of optical input/output ports and at least one Ethernet port. The at least one DAU includes a Framer/Deframer operable to separate cellular payload data from IP data and a network switch operable to buffer the cellular payload data and the IP data and to route the IP data received from the plurality of DRUs to the at least one Ethernet port of the DAU.

Abstract: A method for operating a DAS includes providing a set of digital remote units (remotes) operable to send and receive wireless radio signals. Each of the set of remotes is associated with a geographic area. The method also includes providing a digital access unit (host) operable to communicate with the set of remotes, receiving uplink signals at one or more of the set of remotes, and monitoring train activity in the geographic areas. The method further includes increasing a gain coefficient associated with one of the set of remotes in response to determining an increase in monitored train activity, decreasing a gain coefficient associated with another of the set of remotes in response to determining a decrease in monitored train activity, and transmitting, to the host, scaled uplink signals associated with the one of the set of remotes and the another of the set of remotes.