The present disclosure provides, for example, methods for measuring interference to a cable modem (CM), and corresponding example apparatuses and systems. One example method includes sending, by a cable modem termination system (CMTS), a broadcast message to all CMs connected to the CMTS, where the broadcast message includes information designating one of the CMs to send a probing signal by using a spectrum S in a timeslot T. The CMTS can then broadcast a pseudo random binary sequence (PRBS) by using the spectrum S in a downlink direction in the timeslot T, and can obtaining modulation error ratio (MER) information recorded in the timeslot T by other CMs. A difference between MER information in the timeslot T and MER information in a normal data timeslot can be used, for each of the other CMs, as intensity of interference to the corresponding CM.

A communication apparatus has a receiver that is capable of receiving an alternating phase signal and a tuned circuit whose input is adjusted to be capable of receiving the alternating phase signal. The communication apparatus can be used with both wireless and wired communication links and provide enable faster data rates, greater immunity to noise, increased bandwidth/spectrum efficiency and/or other benefits. Applications include but are not limited to: cell phones, smartphones (e.g., iPhone, BlackBerry, etc.), wireless Internet, local area networks (e.g., WiFi type applications), wide area networks (e.g., WiMAX type applications), personal digital assistants, computers, Internet service providers and communications satellites.

A communication apparatus has a receiver that is capable of receiving an alternating phase signal and a tuned circuit whose input is adjusted to be capable of receiving the alternating phase signal. The communication apparatus can be used with both wireless and wired communication links and provide enable faster data rates, greater immunity to noise, increased bandwidth/spectrum efficiency and/or other benefits. Applications include but are not limited to: cell phones, smartphones (e.g., iPhone, BlackBerry, etc.), wireless Internet, local area networks (e.g., WiFi type applications), wide area networks (e.g., WiMAX type applications), personal digital assistants, computers, Internet service providers and communications satellites.

In a method in which a compensation coefficient calculating portion (6) calculates a compensation coefficient of a compensation portion (5) which compensates transmission characteristics of a signal, a known signal is extracted from the signal. Next, a pseudo-random number is added to the extracted known signal. Next, the compensation coefficient is calculated by comparing a true value of the known signal with the known signal to which the pseudo-random number is added.

In a method in which a compensation coefficient calculating portion (6) calculates a compensation coefficient of a compensation portion (5) which compensates transmission characteristics of a signal, a known signal is extracted from the signal. Next, a pseudo-random number is added to the extracted known signal. Next, the compensation coefficient is calculated by comparing a true value of the known signal with the known signal to which the pseudo-random number is added.

The present disclosure provides, for example, methods for measuring interference to a cable modem (CM), and corresponding example apparatuses and systems. One example method includes sending, by a cable modem termination system (CMTS), a broadcast message to all CMs connected to the CMTS, where the broadcast message includes information designating one of the CMs to send a probing signal by using a spectrum S in a timeslot T. The CMTS can then broadcast a pseudo random binary sequence (PRBS) by using the spectrum S in a downlink direction in the timeslot T, and can obtaining modulation error ratio (MER) information recorded in the timeslot T by other CMs. A difference between MER information in the timeslot T and MER information in a normal data timeslot can be used, for each of the other CMs, as intensity of interference to the corresponding CM.

Method, apparatus and system for crosstalk suppression of power line communication are provided. The method includes: receiving a joining request message; judging a matching state of the communication terminal based on a history matching record and communication terminal identifier, if matching state of the communication terminal is unmatched: sending a joining response message to the communication terminal; receiving an acknowledgment request message sent by the communication terminal after switch of the communication terminal is turned on; detecting voltage on power line between the communication terminal and an inverter corresponding to the power line communication transmitter, if voltage is within preset voltage range, sending an acknowledgment response message to the communication terminal; storing communication terminal identifier in history matching record and storing matching state of the communication terminal as successfully-matched. The method, apparatus and system can avoid malfunction of switch of the communication terminal during communication crosstalk.

Method, apparatus and system for crosstalk suppression of power line communication are provided. The method includes: receiving a joining request message; judging a matching state of the communication terminal based on a history matching record and communication terminal identifier, if matching state of the communication terminal is unmatched: sending a joining response message to the communication terminal; receiving an acknowledgment request message sent by the communication terminal after switch of the communication terminal is turned on; detecting voltage on power line between the communication terminal and an inverter corresponding to the power line communication transmitter, if voltage is within preset voltage range, sending an acknowledgment response message to the communication terminal; storing communication terminal identifier in history matching record and storing matching state of the communication terminal as successfully-matched. The method, apparatus and system can avoid malfunction of switch of the communication terminal during communication crosstalk.

Apparatus and methods for signal booster systems with compensation for cable loss are provided herein. In certain configurations, a signal booster system includes two or more antennas for wirelessly communicating RF signals and a signal booster including booster circuitry for providing amplification to at least a portion of the RF signals. At least one of the antennas is connected to the signal booster via a cable. Additionally, the signal booster includes a cable loss compensation circuit that adjusts a gain of the booster circuitry to compensate for a loss of the cable.

Apparatus and methods for signal booster systems with compensation for cable loss are provided herein. In certain configurations, a signal booster system includes two or more antennas for wirelessly communicating RF signals and a signal booster including booster circuitry for providing amplification to at least a portion of the RF signals. At least one of the antennas is connected to the signal booster via a cable. Additionally, the signal booster includes a cable loss compensation circuit that adjusts a gain of the booster circuitry to compensate for a loss of the cable.