Abstract: A microwave backhaul system having quadruple capacity. In one embodiment, an outdoor communication unit in a microwave backhaul system is provided, which includes a first and second dual channel processing modules that are each configured to process two transmission/reception channels. The outdoor communication unit also includes two transmitter modules that are each configured to upconvert two channels for transmission at vertical polarization and a horizontal polarization.

Abstract: A system and method for sampling an RF signal uses a plurality of capacitors, a plurality of resistors, and a sampling circuit. A first port of each capacitor of the plurality of capacitors is coupled to the RF signal. A first port of each resistor of the plurality of resistors is coupled to one of a plurality of reference levels. A second port of each resistor of the plurality of resistors is coupled to a second port of a corresponding capacitor of the plurality of capacitors. The sampling circuit produces a plurality of digital outputs by sampling the second port of each resistor of the plurality of resistors.

Abstract: In the subject system, a receiver includes a feed forward circuit, a phase recovery circuit, and a feedback circuit. The feed forward circuit compensates for near reflections and provides an input to the phase recovery circuit and the feedback circuit. The phase recovery circuit performs phase recovery and provides phase recovery information to the feedback circuit. The feedback circuit adjusts and/or corrects a received symbol based at least in part on the received phase recovery information.

Abstract: An advanced split microwave architecture is provided. The advanced split microwave architecture includes a smart outdoor communication unit including a digital N-Plexer configured to multiplex and/or demultiplex a received data signal in the digital domain, a processor unit configured to carry out instructions to control operation of the digital N-Plexer, and a converter module configured to convert the received data signal between the digital domain and the analog domain. The smart outdoor communication unit further includes an RF module, having digital capabilities, configured to correct errors within the received data signal in the digital domain, perform a conversion of the received data signal, to amplify a power of the received data signal, and to perform automatic gain control in the digital domain.

Abstract: Methods and systems are provided for calibrating voltage-controlled oscillators (VCOs). frequency control information, relating to output frequency of a VCO, which varies based on changes in operational conditions, may be determined. The frequency control information enables indicating the output frequency within a range of allowable values for control inputs and a range of expected values based on the operational conditions. For each control input setting, calibration control information for a calibration voltage associated with a control input, may be determined, based on the frequency control information, with respect to the operational conditions, to generate a constant output frequency. The operational conditions may be assessed, and a calibration voltage corresponding to the assessed operational conditions may be determined.

Abstract: The continuous demand for capacity and the limited available spectrum in wireless and wired communication has led to reliance on advanced modulation techniques to dramatically increase the number of bits per hertz per second. This demand in capacity and using the higher order constellations shorten the link range, and as a result, system gain becomes an important characteristic. The modulation techniques described here improve the system gain by, e.g., as much as 2.5 dB in high order modulations such as 4096-QAM. The modulation techniques include reducing the peak to average ratio and adding shaping gain. These techniques dramatically improve the system capacity, system gain, power consumption and system cost.

Abstract: Methods and systems are provided for gain control in circuits. Gain applied in a circuit may be set to a baseline set gain. A first baseline parameter, associated with a first feature of a particular pattern of a signal at said baseline set gain, and a second baseline parameter, associated with a second feature of said particular pattern of the signal at said baseline set gain, may be determined. The gain is then set a current set gain, and a gain compression ratio may be determined based on one or more of said first baseline parameter, said second baseline parameter, a first current parameter associated with said first feature of at said current set gain, and a second current parameter associated with said second feature at said current set gain. Said current set gain may then be adjusted until said gain compression ratio reaches a predefined limit.

Abstract: A 5G base station transmitter at least partially precodes data for beam forming, and generates digital precoded baseband signals. Cross product circuitry coupled to the digital precoder, generates digital cross products of the digital precoded baseband signals. Both the baseband signals and the cross products are put through digital-to-analog converters (DACs), then provided to an analog non-linear precoder. The analog non-linear precoder combines the analog baseband signals, the cross products, with pre-distortion and precoder coefficients to generate a signal that is pre-compensated for power amplifier non-linearity. The pre-compensated signal is amplified by the power amplifier and transmitted via a phased antenna array. The number of extra DACs required for inserting pre-distortion when a hybrid digital/analog precoder is used can be limited to approximately N RF ? ( N RF - 1 ) 2 , where NRF is the number of outputs of the digital precoder.

Abstract: A communication system includes a conversion module configured to convert a signal between a radio frequency baseband (RF-BB) and an intermediate frequency (IF). At least one RF front-end module converts the signal between the IF and a radio frequency (RF). The RF front-end module is configured as an RF phased array and includes a coaxial interconnect configured to connect the conversion module with the RF front-end module. The signal is transmitted between the conversion module and the RF-front end module via the coaxial interconnect. At least one RF front-end module includes an active front-end (AFE) configured to allow the signal to be transmitted via the coaxial interconnect while minimizing any deterioration of the signal.

Abstract: Methods and systems are provided for converting wideband signals. In an example system, a wideband signal that includes one or more narrowband signals may be received and handled, with the handling may include selecting a subset of signal processing circuits, from a plurality of signal processing circuits in the system, with the number of selected signal processing circuits being less than the total number of signal processing circuits in the system. Only the selected signal processing circuits are then enabled, such that all remaining signal processing circuits are not enabled. Signal processing adjustment may then be applied, via the subset of signal processing circuits, only to the one or more narrowband signals, such that a remainder of the wideband signal is not adjusted. The handling of the received wideband signal may include separating the one or more narrowband signals from the wideband signal.

Abstract: An Interleaved Radio Frequency Digital-to-Analog Converter (RF DAC) suitable for use in cellular base stations and optimized to give both a wide RF tuning range and a wide RF bandwidth is disclosed. The RF DAC uses two levels of interleaving, the first providing a direct conversion path from Base Band (BB) to RF, and the second providing a variable interleaving factor through the use of summation to optimize the output bandwidth as a function of the RF center frequency. Digital Interpolation, including an arbitrary sample rate conversion filter, allows the RF DAC to operate from a wide range of possible BB sample rates and the DAC sample rate is a fixed ratio of the RF center frequency. As a result, the spurious outputs from the RF DAC are in known locations that are relatively easy to filter out, minimizing the frequency planning tasks required for a complete RF system design.

Abstract: Methods and systems are provided for adaptively configuring voltage-controlled oscillator (VCO) arrays, such as to reduce mismatches among the VCOs. A plurality of voltage-controlled oscillators (VCOs), connected in parallel to a common control input, and with each VCO outputting an oscillating signal based on the common control input and an adjustment input, may be configured to reduce mismatches among the VCOs. The plurality of VCO may be configured by adjusting at least one operational parameter applicable to interconnection paths connecting outputs of the plurality of VCOs; measuring a mismatch between signals at the outputs of the plurality of VCOs with respect to a first signal parameter; and adjusting a first operational parameter applicable to one or more of the plurality of VCOs to reduce mismatch between signals at the outputs of the plurality of VCOs with respect to a first signal parameter.

Abstract: The present disclosure is directed to a modular and scalable front-end architecture for a massive MIMO communication device, such as a base station. The front-end architecture can allow for the number of antennas at the communication device to be increased or decreased in a simple and cost efficient manner. The front-end architecture can also allow for the number of data streams that can be transmitted and/or received by the communication device to be increased or decreased in a simple and cost efficient manner.

Abstract: A transmit (TX) signal path circuit in a multiple-input, multiple-output (MIMO) transceiver responsive to a digital front end (DFE) for generating receive (RX) path phase alignment signals is disclosed. A digital up-conversion block uses a first numerically-controlled oscillator (NCO) for generating digital intermediate frequency (IF) signals for ordinary TX signal generation, and a different, second NCO for generating digital IF signals for RX phase alignment signal generation. An RF up-conversion block uses a TX local oscillator (LO) for generating analog RF signals for ordinary TX signal generation, and a different feedback (FB) LO for generating analog RF signals for RX phase alignment signal generation. Thus, phase alignment of the circuitry used for ordinary TX signal generation is left undisturbed by RX phase alignment signal generation.

Abstract: Systems and methods enable a plurality of modems in a microwave network receive a plurality of frames from a previous one of the plurality of modems and detect an error frame within the plurality of frames. The plurality of modems can be further configured to send a retransmission request to the previous modem upon detection of the error frame and transmit a dummy frame in place of the error frame to a next one of the plurality of modems.

Abstract: A system and method for frequency reuse for wireless point-to-point backhaul. Frequency reuse is enabled through the cancellation of interfering signals generated by interference sources. In one embodiment, a conventional dish antenna is complemented with one or more additional auxiliary antennas (e.g., isotropic). The one or more additional auxiliary antennas enable cancellation of interfering signals whose direction of arrival (DOA) is off the dish antenna's bore-sight.

Abstract: To provide for higher data rates, a wireless back haul network for connecting small cell base stations to a core network can be implemented using full-duplex over single channel communications. The difficulty with full-duplex over single channel communications, and the reason why it has not become common place in wireless and mobile communication standards to date, is the significant interference that the receiver of a full-duplex communication device will generally experience from the full-duplex communication device's own transmitter transmitting over the same channel that the receiver is to receive signals. This interference is referred to as self-interference because the interference experienced by the receiver originates from its own paired transmitter. The present disclosure describes embodiments of an apparatus and method that provide sufficient self-interference cancellation in a compact and power efficient manner for a small cell wireless backhaul network.

Abstract: A point-to-point (PtP) communication system includes a near end antenna device configured to transmit a narrow antenna beam over a wireless link, and includes a far end antenna device configured receive the narrow antenna beam over the wireless link. The near end antenna device including a directive element configured to focus an electrical field into the narrow antenna beam, and including a beam steering element (e.g., a phased array feeder (PAF) assembly) configured to generate the electrical field and to track the far end antenna, and further including a communication interface unit (e.g., an outdoor unit) configured to perform operations on a transmitted signal and a received signal.

Abstract: The continuous demand for capacity and the limited available spectrum in wireless and wired communication has led to reliance on advanced modulation techniques to dramatically increase the number of bits per hertz per second. This demand in capacity and using the higher order constellations shorten the link range, and as a result, system gain becomes an important characteristic. The modulation techniques described here improve the system gain by, e.g., as much as 2.5 dB in high order modulations such as 4096-QAM. The modulation techniques include reducing the peak to average ratio and adding shaping gain. These techniques dramatically improve the system capacity, system gain, power consumption and system cost.

Abstract: The continuous demand for capacity and the limited available spectrum in wireless and wired communication has led to reliance on advanced modulation techniques to dramatically increase the number of bits per hertz per second. This demand in capacity and using the higher order constellations shorten the link range, and as a result, system gain becomes an important characteristic. The modulation techniques described here improve the system gain by, e.g., as much as 2.5 dB in high order modulations such as 4096-QAM. The modulation techniques include reducing the peak to average ratio and adding shaping gain. These techniques dramatically improve the system capacity, system gain, power consumption and system cost.