A method is for processing an analog channel signal from a transmission channel. The method may include converting of the analog channel signal to a digital channel signal, and performing a channel estimation digital processing of the digital channel signal. The channel estimation digital processing may include for at least one frame, generating transfer functions of the transmission channel, the transfer functions respectively associated with reference symbols of the frame, and averaging processing of the transfer functions to generate an average transfer function. The method may include decoding of symbols of the frame following the reference symbols using the average transfer function.

A broadband powerline communication system makes use of knowledge of the spectrum characteristics of a local radio environment in order to improve system performance. A determination is made of the spectrum characteristics of a radio environment in the vicinity of the broadband powerline communication system that is transmitting data on modulated carrier frequencies. In order to avoid interference, certain ones of the carrier frequencies otherwise used by the broadband powerline communication system may be selectively masked based on the determination. The spectrum characteristics may be determined 1) in advance and used to compile a configuration database comprising frequency masking parameters; 2) by monitoring the local radio environment using the transmitter/receiver nodes of the system; or 3) based upon receipt of an indication from a conflicting user that the user is experiencing interference. Various combinations of these spectrum characteristic determination techniques may also be used.

Transmission over a communication channel using carrier sense multiple access collision avoidance (CSMA/CA) may be performed by determining for each frame if the communication channel is busy after a backoff time proportional to a randomly generated number within a contention window (CW). When the channel is not busy, a frame of data may be transmitted. When the channel is busy, the device may periodically determine if the communication channel is busy after subsequent backoff times. The value of CW is adjusted for each subsequent backoff time using a fairness protocol, in which the value of CW is increased until the value of CW reaches a maximum CW value; and then the value of CW is held until a fairness number of backoff repetitions reaches a fairness threshold; then the value of CW is reduced incrementally until the value of CW reaches a minimum CW value.

A method includes digital/analog conversion of a digital signal modulated by information to provide a modulated initial analog signal having a crest factor greater than one, and amplification of the initial analog signal to provide an amplified modulated signal. A modulated channel analog signal derived from the modulated amplified analog signal is transmitted over a communications channel, with impedance of the communications channel varying during the transmission. The method further includes at least one determination during the transmission of a peak-clipping rate of the amplified analog signal over at least one time interval, and an adjustment of a level of the initial analog signal as a function of the determined peak-clipping rate.

A device for power line communication is provided, including a transmitter adapted to transmit signals on at least two of a plurality of power line transmission paths of a power line network; a sensor adapted to determine one or a plurality of reflection parameters of one of the plurality of power line transmission paths; and a transmission impedance matching unit adapted to match the output impedance of at least two output ports of the device which each couple to one of the plurality of transmission paths to the impedance of the at least two of the power line transmission paths based on the one or the plurality of reflection parameters. Further, a device including a corresponding reception impedance matching unit is provided and corresponding methods for transmitting and receiving signals.

The present invention relates to tackifier compounds and methods of using the same. In various embodiments, the present invention provides a tackifier compound including independently substituted or unsubstituted fused rings A and B each independently chosen from (C.sub.5-C.sub.10)cycloalkyl and (C.sub.2-C.sub.10)heterocyclyl. Fused ring A is substituted with (R.sup.1).sub.1-8 and fused ring B is substituted with (OC(O)RC(O)R.sup.2).sub.1-8. At each occurrence R is independently chosen from (C.sub.2-C.sub.10)alkanylene, (C.sub.2-C.sub.10)alkenylene, (C.sub.2-C.sub.10)alkynylene, (C.sub.5-C.sub.20(arylene), and (C.sub.1-C.sub.20)heteroarylene, wherein R is unsubstituted or substituted. At each occurrence R is independently selected from OH, OR.sup.3, and OC(O)RC(O)R.sup.2. At each occurrence R.sup.2 is independently chosen from OH, OR.sup.3, NH.sub.2, NHR.sup.3, and NR.sup.3.sub.2. At each occurrence R.sup.3 is independently chosen from (C.sub.1-C.sub.10)alkanyl, (C.sub.2-C.sub.10)alkenyl, (C.sub.2-C.sub.10)alkynyl, C.sub.5-C.sub.20(aryl), and (C.sub.1-C.sub.20)heteroaryl, wherein R.sup.3 is unsubstituted or substituted.

A slave control device receives a communication signal from a master control device, and controls loads according to the received communication signal. A modulator superimposes the communication signal from the master control device on power source lines, and a demodulator demodulates the communication signal superimposed on the power source lines and supplies the demodulated communication signal to the slave control device. The modulator is provided on power source lines on a battery side, and the demodulator is provided on the power source lines on a load side. The modulator superimposes the communication signal on the power source lines which are on a side closer to the loads with respect to the modulator among the power source lines.

A method includes digital/analog conversion of a digital signal modulated by information to provide a modulated initial analog signal having a crest factor greater than one, and amplification of the initial analog signal to provide an amplified modulated signal. A modulated channel analog signal derived from the modulated amplified analog signal is transmitted over a communications channel, with impedance of the communications channel varying during the transmission. The method further includes at least one determination during the transmission of a peak-clipping rate of the amplified analog signal over at least one time interval, and an adjustment of a level of the initial analog signal as a function of the determined peak-clipping rate.

The present invention relates to tackifier compounds and methods of using the same. In various embodiments, the present invention provides a tackifier compound including independently substituted or unsubstituted fused rings A and B each independently chosen from (C.sub.5-C.sub.10)cycloalkyl and (C.sub.2-C.sub.10)heterocyclyl. Fused ring A is substituted with (R.sup.1).sub.1-8 and fused ring B is substituted with (OC(O)RC(O)R.sup.2).sub.1-8. At each occurrence R is independently chosen from (C.sub.2-C.sub.10)alkanylene, (C.sub.2-C.sub.10)alkenylene, (C.sub.2-C.sub.10)alkynylene, C.sub.5-C.sub.20(arylene), and (C.sub.1-C.sub.20)heteroarylene, wherein R is unsubstituted or substituted. At each occurrence R.sup.1 is independently selected from OH, OR.sup.3, and OC(O)RC(O)R.sup.2. At each occurrence R.sup.2 is independently chosen from OH, OR.sup.3, NH.sub.2, NHR.sup.3, and NR.sup.3.sub.2. At each occurrence R.sup.3 is independently chosen from (C.sub.1-C.sub.10)alkanyl, (C.sub.2-C.sub.10)alkenyl, (C.sub.2-C.sub.10)alkynyl, C.sub.5-C.sub.20(aryl), and (C.sub.1-C.sub.20)heteroaryl, wherein R.sup.3 is unsubstituted or substituted.

A method is for processing an analog channel signal from a transmission channel. The method may include converting of the analog channel signal to a digital channel signal, and performing a channel estimation digital processing of the digital channel signal. The channel estimation digital processing may include for at least one frame, generating transfer functions of the transmission channel, the transfer functions respectively associated with reference symbols of the frame, and averaging processing of the transfer functions to generate an average transfer function. The method may include decoding of symbols of the frame following the reference symbols using the average transfer function.