Patent ID: 7130364
Filing Date: 2006-10-31
Classification: H04B

Abstract:
1. A receiver circuit for adjusting the headroom for a received signal in a radio receiver, the received signal including a target signal and an interference signal, the circuit comprising: an amplifier coupled with the received signal such that the amplifier outputs an amplified signal, the amplification level of the amplifier being set by an amplifier control signal; an analog-to-digital converter coupled with the amplified signal, the analog-to-digital converter outputting a digital signal wherein the digital signal is a digital representation of the amplified signal; a first digital filter having a first filter input coupled with the digital signal, the first digital filter filters the digital signal at a first interference attenuation factor to produce a first filter output, the first filter output comprising the amplifier control signal, the first filter output being proportional to the magnitude of the interference signal when the interference signal is greater in magnitude than the target signal thereby to cause the amplification level set by the amplifier to be proportional to the magnitude of the interference signal; and a second digital filter having a second filter input coupled with the first filter output, the second digital filter filters the first filter output at a second interference attenuation factor.