In an embodiment, a remote antenna unit includes a transmitter, a receiver, an antenna array, and first and second interference circuits. The transmitter is configured to generate at least one transmit signal, and the receiver is configured to process at least one receive signal. The antenna array includes one or more antennas, each of at least one of the one or more antennas coupled to the transmitter and configured to radiate a respective downlink signal in response to a respective one of the at least one transmit signal, and each of at least one of the one or more antennas coupled to the receiver and configured to generate a respective one of the at least one receive signal in response to an uplink signal. And the first and second interference circuits are each coupled to the transmitter and to the receiver and are each configured to reduce interference in each of the at least one receive signal.

Systems, methods, and devices perform channel interference detection for wireless devices. Methods include receiving a signal at a wireless device, the signal including at least one data subcarrier and one or more guard subcarriers. Methods also include determining, using processing logic, that one or more guard subcarriers are available for adjacent channel interference (ACI) detection, measuring, using the processing logic, a power of each of the one or more guard subcarriers and a total power of the one or more guard subcarriers, and determining, using the processing logic, an ACI is present based, at least in part, on the measurements of the one or more guard subcarriers. Methods further include performing, using the processing logic, one or more deweighing operations based on one or more identified features of the ACI.

Systems and method are described for improving electrical isolation between a transmission signal and receiver circuitry of a transceiver communicating over one or more wireless networks via one or more shared antennas. The transceiver may include isolation circuitry to facilitate isolation of the transmission signal from the receiver circuitry. However, a leakage current of the transmission signal and noise signals may appear at the receiver circuitry. Presence of the leakage current or the noise signals in the receiver circuitry may cause interference with the reception signal. As such, the isolation circuitry may benefit from additional isolation between the transmission signal and the receiver circuitry to reduce an effect of the leakage current and the noise signals on the reception signal.

A method for leakage detection in an aeronautical band for a high split HFC network includes: providing a vehicle borne leak detector configured to perform substantially simultaneous upstream and downstream leakage detection; and while traversing a hub containing any quantity of high split nodes, performing a substantially simultaneous upstream leakage detection and a downstream leakage detection at about a same frequency. A system for leakage detection in an aeronautical band for a high split HFC network is also described.

A method for leakage detection in an aeronautical band for a high split HFC network includes: providing a vehicle borne leak detector configured to perform substantially simultaneous upstream and downstream leakage detection; and while traversing a hub containing any quantity of high split nodes, performing a substantially simultaneous upstream leakage detection and a downstream leakage detection at about a same frequency. A system for leakage detection in an aeronautical band for a high split HFC network is also described.

The present application provides a method for calibrating a transmitter. The transmitter includes an oscillator, a first signal path, and a second signal path. The first signal path and the second signal path include a first calibration unit preceding a first low pass filter and a second low pass filter, and a second calibration unit succeeding the first low pass filter and the second low pass filter. The calibration method includes: by configuring the first calibration unit and the second calibration unit and sending a transmission signal, and performing frequency analysis upon the transmission signal to obtain a frequency analysis result, to generate an optimized first compensation value for the first calibration unit and an optimized second compensation value for the second calibration unit.

The present disclosure provides a method and a system to estimate LO leakage and quadrature error parameters for a transmitter RF front end, such as a direct up-conversion transmitter RF front end, in a joint fashion. The proposed method utilizes a PN sequence inserted at the transmitter baseband. At the observation receiver side, an RX accumulator is implemented to sum receiver signals to take advantage of a despreading gain using the same PN sequence from transmitter side. Through the despreading process, the receiver-transmitter channel may be estimated and used to extract the quadrature error parameters. The estimated channel may also be used to eliminate user data interference presented within the RX accumulator output, which may further be used to compute the LO leakage.

The present disclosure provides a method and a system to estimate LO leakage and quadrature error parameters for a transmitter RF front end, such as a direct up-conversion transmitter RF front end, in a joint fashion. The proposed method utilizes a PN sequence inserted at the transmitter baseband. At the observation receiver side, an RX accumulator is implemented to sum receiver signals to take advantage of a despreading gain using the same PN sequence from transmitter side. Through the despreading process, the receiver-transmitter channel may be estimated and used to extract the quadrature error parameters. The estimated channel may also be used to eliminate user data interference presented within the RX accumulator output, which may further be used to compute the LO leakage.

Signals used to test for upstream signal leaks in a hybrid fiber-coaxial (HFC) network may be interleaved with client data and strategically timed to be received by a leak detection device with a one-hundred percent probability of intercept. A method includes receiving an indication that a user device is in proximity to a computing device. The method includes determining, based on the indication that the user device is in proximity to the computing device, signal information. The method includes causing, based on the signal information, the user device to output a signal. The method includes determining, based on an indication that the signal was received by the computing device, a location of a network leak.

Systems and methods for detecting leakage in a cable network system are disclosed. In at least some illustrative embodiments, a system may include a digital tagger operable to generate a digital tag including a chirp signal configured to be placed on a downstream signal path of the cable network system, and a cable network test instrument configured detect the digital tag in wireless signal data received from the cable network system when a point of ingress is presented in the cable network system. The network test instrument may be operable to provide a user-perceptible indication when the digital tag is detected to inform a technician or other user that a flaw in the cable network system is nearby.