Abstract: A digital pre-distortion system can inversely model a power amplifier of a system to linearize the transmitter. A complex baseband model for digital pre-distortion based on a narrowband signal assumption is unworkable for an ultra wide band Cable television application. Predistortion can use a true wide band model including real-valued basis terms, obtained from a real-valued signal. When raised to a power, both even and odd harmonics or both odd or even other non-linear terms are represented and negative frequency fold-over can be accounted for. A Hilbert transform can be applied. Compressed sensing can be used to reduce the number of basis terms in the true real wide band model to generate a sparse model. Sparse equalization can be added to improve the stability of the digital pre-distortion system.

Abstract: A digital pre-distortion system can inversely model a power amplifier of a system to linearize the transmitter. A complex baseband model for digital pre-distortion based on a narrowband signal assumption is unworkable for an ultra wide band Cable television application. Predistortion can use a true wide band model including real-valued basis terms, obtained from a real-valued signal. When raised to a power, both even and odd harmonics or both odd or even other non-linear terms are represented and negative frequency fold-over can be accounted for. A Hilbert transform can be applied. Compressed sensing can be used to reduce the number of basis terms in the true real wide band model to generate a sparse model. Sparse equalization can be added to improve the stability of the digital pre-distortion system.

Abstract: Aspects of this disclosure relate to protecting a circuit, such as an amplifier, from transient overdrive events and/or average overdrive events. In one embodiment, an indication of average power, such as root mean squared (RMS) power of a radio frequency (RF) signal, can be compared to a first threshold and an indication of a peak RF power can be compared to a second threshold. When the indication of average power exceeds the first threshold, an average overdrive event can be detected. When the indication of peak power exceeds the second threshold, a peak overdrive event can be detected. If either a transient overdrive event or an average overdrive event is detected, a circuit, such as an amplifier, can be protected.

Abstract: Aspects of this disclosure relate to protecting a circuit, such as an amplifier, from transient overdrive events and/or average overdrive events. In one embodiment, an indication of average power, such as root mean squared (RMS) power of a radio frequency (RF) signal, can be compared to a first threshold and an indication of a peak RF power can be compared to a second threshold. When the indication of average power exceeds the first threshold, an average overdrive event can be detected. When the indication of peak power exceeds the second threshold, a peak overdrive event can be detected. If either a transient overdrive event or an average overdrive event is detected, a circuit, such as an amplifier, can be protected.