Described is an apparatus which comprises: a first capacitor coupled to a first input pad; a second capacitor coupled to second input pad; a first resistor coupled to the second capacitor; a third capacitor coupled in series with the first resistor; a second resistor coupled in series with the third capacitor and also coupled to the first capacitor; and a differential amplifier coupled to the first and second capacitors and to the first and second resistors.

Described is an apparatus which comprises: a first capacitor coupled to a first input pad; a second capacitor coupled to second input pad; a first resistor coupled to the second capacitor; a third capacitor coupled in series with the first resistor; a second resistor coupled in series with the third capacitor and also coupled to the first capacitor; and a differential amplifier coupled to the first and second capacitors and to the first and second resistors.

In an RF transmitter, a digital predistortion circuit receives a sequence of input sample blocks, and performs a digital predistortion process to produce a predistorted output signal. The digital predistortion process includes selecting a set of predistortion coefficients for an input sample block from a plurality of different sets of predistortion coefficients. Each of the plurality of different sets of predistortion coefficients is associated with a different combination of one of a plurality of time slices within a radio frame and one of a plurality of power ranges. The selected set of predistortion coefficients is associated with a time slice within which the input sample block is positioned and a power range calculated for the input sample block based on block power statistics of the sample block. The process also includes applying the selected set of predistortion coefficients to the input sample block to produce the predistorted output signal.

In an RF transmitter, a digital predistortion circuit receives a sequence of input sample blocks, and performs a digital predistortion process to produce a predistorted output signal. The digital predistortion process includes selecting a set of predistortion coefficients for an input sample block from a plurality of different sets of predistortion coefficients. Each of the plurality of different sets of predistortion coefficients is associated with a different combination of one of a plurality of time slices within a radio frame and one of a plurality of power ranges. The selected set of predistortion coefficients is associated with a time slice within which the input sample block is positioned and a power range calculated for the input sample block based on block power statistics of the sample block. The process also includes applying the selected set of predistortion coefficients to the input sample block to produce the predistorted output signal.

In an RF transmitter, a digital predistortion circuit receives a sequence of input sample blocks, and performs a digital predistortion process to produce a predistorted output signal. The digital predistortion process includes selecting a set of predistortion coefficients for an input sample block from a plurality of different sets of predistortion coefficients. Each of the plurality of different sets of predistortion coefficients is associated with a different combination of one of a plurality of time slices within a radio frame and one of a plurality of power ranges. The selected set of predistortion coefficients is associated with a time slice within which the input sample block is positioned and a power range calculated for the input sample block based on block power statistics of the sample block. The process also includes applying the selected set of predistortion coefficients to the input sample block to produce the predistorted output signal.

In an RF transmitter, a digital predistortion circuit receives a sequence of input sample blocks, and performs a digital predistortion process to produce a predistorted output signal. The digital predistortion process includes selecting a set of predistortion coefficients for an input sample block from a plurality of different sets of predistortion coefficients. Each of the plurality of different sets of predistortion coefficients is associated with a different combination of one of a plurality of time slices within a radio frame and one of a plurality of power ranges. The selected set of predistortion coefficients is associated with a time slice within which the input sample block is positioned and a power range calculated for the input sample block based on block power statistics of the sample block. The process also includes applying the selected set of predistortion coefficients to the input sample block to produce the predistorted output signal.

Disclosed is a method and apparatus for reducing outbound interference in a broadband powerline communication system. Data is modulated on first and second carrier frequencies and is transmitted via respective first and second lines of the powerline system. A characteristic of at least one of the carrier signals (e.g., phase or amplitude) is adjusted in order to improve the electrical balance of the lines of the transmission system. This improvement in electrical balance reduces the radiated interference of the powerline system. Also disclosed is the use of a line balancing element on or more lines of the powerline system for altering the characteristics of at least one of the power lines in order to compensate for a known imbalance of the transmission system.

The present invention relates to a method and an apparatus for direct current offset calibration of a direct conversion receiver, a Direct Current (DC) offset calibration apparatus of a direct conversion receiver includes a plurality of variable gain amplifiers for amplifying an input signal based on a gain control value, a DC offset monitoring unit for monitoring a DC offset for an output signal of the plurality of variable gain amplifiers, a plurality of variable Digital to Analog Converters (DACs) for controlling a current applied to each of the plurality of variable gain amplifiers according to a current control code, and a DC offset cancellation unit for determining a current control code set which minimizes the DC offset value per preset gain control value, and thus the DC offset can be precisely cancelled without being affected by external factors such as a signal modulation method and heat and performance degradation of the receiver can be prevented.

A compensation circuit is configured to compensate for a loss of low-frequency signal content of an input signal at a receiver input. The compensation circuit includes a switching circuit and a summing circuit coupled to the switching circuit. The switching circuit is configured to receive a first plurality of digitized values sampled from a receiver output signal. The summing circuit is configured to generate a summation signal based on a combination of a first plurality of input values selected by the switching circuit. The selecting is based on the first plurality of digitized values. The compensation circuit is configured to provide to the receiver input a compensation signal to compensate for the loss of the low-frequency signal content from the input signal. The compensation signal is based on the summation signal and is a function of at least one gain value.

A compensation circuit is configured to compensate for a loss of low-frequency signal content of an input signal at a receiver input. The compensation circuit includes a switching circuit and a summing circuit coupled to the switching circuit. The switching circuit is configured to receive a first plurality of digitized values sampled from a receiver output signal. The summing circuit is configured to generate a summation signal based on a combination of a first plurality of input values selected by the switching circuit. The selecting is based on the first plurality of digitized values. The compensation circuit is configured to provide to the receiver input a compensation signal to compensate for the loss of the low-frequency signal content from the input signal. The compensation signal is based on the summation signal and is a function of at least one gain value.