Abstract: Embodiments of the disclosure relate to reducing out-of-channel noise in a wireless distribution system (WDS). A digital filter in a remote unit is configured to suppress out-of-channel noise in a downlink digital communications signal based on at least one filter configuration parameter received from a control circuit. The control circuit is configured to determine the filter configuration parameter based on physical characteristics of the downlink digital communications signal. By suppressing the out-of-channel noise of the downlink digital communications signal, it is possible to provide a downlink RF communications signal communicated from the remote unit that complies with a spectrum emission mask (SEM).

Abstract: Embodiments of the disclosure relate to calibrating a power amplifier. The power amplifier calibration circuit is configured to provide a plurality of bias signal combinations each including a respective first bias signal and a respective second bias signal to the power amplifier. Power amplifier performance parameters for each of the bias signal combinations can be measured and provided to a control circuit in the power amplifier calibration circuit. The control circuit is configured to rank the measured power amplifier performance parameters based on predefined ranking criteria and determines a selected bias signal combination that can optimize the power amplifier performance parameters of the power amplifier. As such, it is possible to calibrate the power amplifier to operate at a balanced performance level, thus helping to improve radio frequency (RF) coverage and performance of the remote unit in a wireless distribution system (WDS).

Abstract: Embodiments of the disclosure relate to a high-directivity directional coupler, and related methods and systems. The high-directivity directional coupler includes a first microstrip and a second microstrip disposed parallel to the first microstrip. The high-directivity directional coupler inherently generates an even mode current and an odd mode current in the second microstrip. The second microstrip provides a linear forward path for conveying the even mode current and a non-linear return path for conveying the odd mode current. The non-linear return path is longer than the linear forward path to compensate for phase velocity difference between the even mode current and the odd mode current. As a result, the odd mode current and the even mode current in the second microstrip can destructively cancel out each other, thus rendering high-directivity without compromising other performance aspects of the high-directivity directional coupler.

Abstract: Embodiments of the disclosure relate to calibrating a power amplifier. The power amplifier calibration circuit is configured to provide a plurality of bias signal combinations each including a respective first bias signal and a respective second bias signal to the power amplifier. Power amplifier performance parameters for each of the bias signal combinations can be measured and provided to a control circuit in the power amplifier calibration circuit. The control circuit is configured to rank the measured power amplifier performance parameters based on predefined ranking criteria and determines a selected bias signal combination that can optimize the power amplifier performance parameters of the power amplifier. As such, it is possible to calibrate the power amplifier to operate at a balanced performance level, thus helping to improve radio frequency (RF) coverage and performance of the remote unit in a wireless distribution system (WDS).

Abstract: Embodiments of the disclosure relate to a high-directivity directional coupler, and related methods and systems. The high-directivity directional coupler includes a first microstrip and a second microstrip disposed parallel to the first microstrip. The high-directivity directional coupler inherently generates an even mode current and an odd mode current in the second microstrip. The second microstrip provides a linear forward path for conveying the even mode current and a non-linear return path for conveying the odd mode current. The non-linear return path is longer than the linear forward path to compensate for phase velocity difference between the even mode current and the odd mode current. As a result, the odd mode current and the even mode current in the second microstrip can destructively cancel out each other, thus rendering high-directivity without compromising other performance aspects of the high-directivity directional coupler.

Abstract: A radio frequency (RF) equalizer includes a coupler including an input port, an output port, a coupling port, and an isolation port; a combination circuit including; a coupling node electrically coupled to the coupling port; a first digitally controlled capacitor (DTC) connected between the coupling node and ground; a resistor connected between the coupling node and ground for controlling a quality factor (Q) of resonance of the equalizer; an isolation node coupled to the isolation port; and a second DTC connected between the isolation node and ground. A system and a method of operation are provided.

Abstract: Embodiments of the disclosure relate to antenna array beamforming in a remote unit(s) in a wireless distribution system (WDS). In this regard, a remote unit in a WDS includes an antenna array having a plurality of radio frequency (RF) antennas. The RF antennas transmit a plurality of modified downlink RF signals in a plurality of phases. A control circuit in the remote unit determines the phases to cause the RF antennas to transmit a formed radiation beam(s) in a radiation direction(s). The control circuit controls a plurality of phase shifters to generate the modified downlink RF signals in the phases. By supporting antenna array beamforming in the remote unit, it is possible to steer the formed radiation beam(s) according to a specific floor layout(s) to provide enhanced indoor RF coverage in the WDS. As a result, it may be possible to reduce deployment and/or installation costs of the WDS.

Abstract: Embodiments of the disclosure relate to reducing out-of-channel noise in a wireless distribution system (WDS). A digital filter in a remote unit is configured to suppress out-of-channel noise in a downlink digital communications signal based on at least one filter configuration parameter received from a control circuit. The control circuit is configured to determine the filter configuration parameter based on physical characteristics of the downlink digital communications signal. By suppressing the out-of-channel noise of the downlink digital communications signal, it is possible to provide a downlink RF communications signal communicated from the remote unit that complies with a spectrum emission mask (SEM).

Abstract: A radio frequency (RF) equalizer includes a coupler including an input port, an output port, a coupling port, and an isolation port; a combination circuit including; a coupling node electrically coupled to the coupling port; a first digitally controlled capacitor (DTC) connected between the coupling node and ground; a resistor connected between the coupling node and ground for controlling a quality factor (Q) of resonance of the equalizer; an isolation node coupled to the isolation port; and a second DTC connected between the isolation node and ground. A system and a method of operation are provided.

Abstract: A radio frequency (RF) equalizer includes a coupler including an input port, an output port, a coupling port, and an isolation port; a combination circuit including; a coupling node electrically coupled to the coupling port; a first digitally controlled capacitor (DTC) connected between the coupling node and ground; a resistor connected between the coupling node and ground for controlling a quality factor (Q) of resonance of the equalizer; an isolation node coupled to the isolation port; and a second DTC connected between the isolation node and ground. A system and a method of operation are provided.

Abstract: A radio frequency (RF) equalizer includes a coupler including an input port, an output port, a coupling port, and an isolation port; a combination circuit including; a coupling node electrically coupled to the coupling port; a first digitally controlled capacitor (DTC) connected between the coupling node and ground; a resistor connected between the coupling node and ground for controlling a quality factor (Q) of resonance of the equalizer; an isolation node coupled to the isolation port; and a second DTC connected between the isolation node and ground. A system and a method of operation are provided.