Abstract: A direct conversion receiver (200) is capable of recovering a filtered baseband signal (295) from a radio signal (201) modulated with a baseband signal (202). The direct conversion receiver (200) comprises a radio frequency mixer (205) for converting the radio signal (201) to the baseband signal (202), a lowpass amplifier (210) DC coupled to the radio frequency mixer (205), that amplifies the baseband signal (202) and substantially attenuates components of the baseband signal above a high corner frequency, and a DC offset compensation section (225) DC coupled to the lowpass amplifier (210), that provides a DC offset compensation and a controlled highpass filtering of the baseband signal. A low corner frequency of the DC offset compensation section is smoothly varied from a predetermined maximum value to a predetermined minimum value during a low frequency, low energy portion of the signaling protocol.

Abstract: A selective call receiver (100) includes a radio frequency amplifier (202) having an output power level that is controllable. A radio frequency level sensor (500) generates a sensor output signal in response to an input signal level received at the radio frequency amplifier (202). The receiver also includes a RSSI signal (208) that indicates a relative strength of an on-channel signal received at the radio frequency amplifier and recovered by the selective call receiver.

Abstract: A selective call receiver (100) includes a radio frequency amplifier (202) having an output power level that is controllable. A radio frequency level sensor (500) generates a sensor output signal in response to an input signal level received at the radio frequency amplifier (202). The sensor output signal is conditioned by a filter (401, 402) to generate a control signal representing an effective value of the input signal level received at the radio frequency amplifier (202). The control signal is then coupled to an amplifier output power level adjustment circuit (403) that operates to adjust a power gain of the radio frequency amplifier (202) in an unconditionally stable feed-forward manner such that the output power level remains substantially constant when the input signal level sensed by the radio frequency level sensor (500) substantially reaches or exceeds a predetermined signal overload level.

Abstract: A selective call receiver (100) includes a radio frequency amplifier (202) having an output power level that is controllable in an unconditionally stable manner. The selective call receiver (100) includes a loading diode (403) coupled to an output of the radio frequency amplifier (202) and a feed-forward load control (201) coupled to an input of the radio frequency amplifier (202). The feed-forward load control (201) detects an input signal strength and regulates conduction of a current through the loading diode (403). In response to the input signal strength substantially reaching or exceeding a predetermined activation threshold corresponding with a predetermined input signal strength and a maximum output power level, the feed-forward load control (201) adjusts the current causing an impedance of the loading diode (403) to vary in a manner that causes the output power level to remain substantially constant.