Apparatus for improving intermodulation distortion characteristics in a CDMA mobile terminal
AssigneeSamsung Electronics Co., Ltd.
InventorHo-Soo Seo
Life of this patent
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Abstract
Disclosed is an apparatus for improving an intermodulation distortion characteristic by controlling a gain of an attenuator in a CDMA mobile terminal. The apparatus includes a converter for passing input signal components except an IF signal component, amplifying the passed input signal to a specific level, converting the amplified signal to a DC signal, comparing the DC signal with first and second thresholds, and generating a control signal for controlling an operating point of the attenuator by synthesizing the compared result signals.
Claims7
An apparatus for improving an intermodulation distortion characteristic by controlling a gain of an attenuator in a CDMA (Code Division Multiple Access) mobile terminal, comprising:
- a converter for passing input signal components except an IF (Intermediate Frequency) signal component, amplifying the passed input signal to a specific level, converting the amplified signal to a DC (Direct Current) signal, comparing the DC signal with first and second thresholds, and generating a control signal for controlling an operating point of the attenuator by synthesizing the compared result signals.
In a CDMA (Code Division Multiple Access) mobile terminal having an attenuator to control an intermodulation distortion characteristic, and a duplexer to feed a received signal to the attenuator which in turn feeds an attenuated signal to a low noise amplifier, the output of which is filtered in an RF filter and the output voltage level of which is controlled by a mixer, the improvement comprising:
- a converter, connected to the output of the mixer, for passing input signal components except an IF (Intermediate Frequency) signal component, amplifying the passed input signal to a specific level, converting the amplified signal to a DC (Direct Current) signal, comparing the DC signal with first and second thresholds, and generating a control signal for controlling an operating point of the attenuator by synthesizing the compared result signals.
In a CDMA (Code Division Multiple Access) mobile terminal having an attenuator to control an intermodulation distortion characteristic, and a duplexer to feed a received signal to the attenuator which in turn feeds an attenuated signal to a low noise amplifier, the output of which is filtered in an RF filter and the output voltage level of which is controlled by a mixer, the improvement comprising:
- a filter, connected to the output of the mixer, for passing the input signal components except the IF signal component;
- an IF amplifier for amplifying a signal output from the filter to the specific level;
- an integrator for converting a signal output from the IF amplifier to a DC signal;
- first and second comparators for comparing a signal output from the integrator with the first and second thresholds, respectively;
- and
- a synthesizer for synthesizing signals output from the first and second comparators.
Dependencies are inferred from the claim text.