Abstract:
A method for processing a plurality of signals may include amplifying an input signal and generating a wideband signal from the amplified input signal. The method may further include bandpass filtering the generated wideband signal to generate a narrowband signal, and adjusting amplification of the input signal based on a narrowband received signal strength indication of the generated narrowband signal, and/or a wideband received signal strength indication of the generated wideband signal. The amplified input signal may be downconverted to generate the wideband signal. The amplified input signal may be downconverted to an intermediate frequency (IF) and/or to a baseband signal to generate the wideband signal. At least one blocker signal may be bandpass filtered from the amplified input signal.
Abstract:
In a receiving circuit, an antenna 11 receives a high-frequency signal at a predetermined frequency band, a level changing section 13 changes a signal level of the high-frequency signal received by the antenna, a subsequent-stage circuit 14 performs predetermined signal processing for the high-frequency signal whose signal level is changed at the level changing section 13, a detecting section 32 detects a signal level of the high-frequency signal for which the signal processing is performed by the subsequent-stage circuit 14, and a control section 33 sets a rate of change of the high-frequency signal by the level changing section 13, based on the signal level of the high-frequency signal detected by the detecting section 32, so that the signal level of the high-frequency signal detected by the detecting section 32 does not exceed a predetermined value.
Abstract:
Either linear operating mode or saturation operating mode is set as the operating mode of a high-frequency power amplifier on the basis of an operating mode set signal. The gain of a variable gain amplifier provided in front of the high-frequency power amplifier and values of output voltage and bias current supplied from a supply voltage/bias current control circuit to the high-frequency power amplifier are switched. The gain of the variable gain amplifier in the saturation operating mode is formed so as to be higher by a predetermined value than that in the linear operating mode. Accordingly, the high-frequency power amplifier operates in the designated operating mode, so that the output transmission power range can be widened.
Abstract:
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, this invention enables preventing waveform distortion near the peak output power level by allowing sufficient idle currents to flow through the transistors for amplification, while enhancing the power efficiency in a low output power region. The power amplifier includes a detection circuit comprising a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage conversion means which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detection and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.
Abstract:
A transmitting method and a transmitter apparatus, which need no manual adjustment, are disclosed. A delay amount is automatically adjusted such that an out-of-band distortion component of a transmission signal is minimized, and a correct timing is produced by the method and the apparatus. In this transmitter apparatus, a first delay adjusts a control timing over a voltage that controls a power amplifier, and a distributor distributes an output from the power amplifier in order to feedback parts of the output. A distortion adjusting units calculating a distortion component of the transmission signal by using the signal fed back by the distributor, and adjusts automatically a delay amount of the first delay so as to minimize the distortion component. This structure allows eliminating manual adjustment, and obtaining high power-efficiency with fewer distortions.
Abstract:
Methods and systems for processing a plurality of signals are disclosed herein. Aspects of the method may comprise amplifying an input signal. The amplified input signal may be bandpass filtered. Amplification of the input signal may be adjusted based on only narrowband received signal strength indication of the bandpass filtered amplified input signal. The amplified input signal may be downconverted and a blocker signal may be bandpass filtered from the amplified input signal. Signal strength of a desired signal from the amplified input signal may be measured. The amplification of the input signal may be adjusted utilizing a triple well (TW) NMOS transistor. A control signal may be generated based on the narrowband received signal strength indication of the bandpass filtered amplified input signal. The amplification of the input signal may be adjusted based on at least one of the generated control signals.
Abstract:
A Variable Gain Amplifier (VGA) amplifies an input signal according to a gain, to produce an amplified signal. A detector module detects a power indicative of a power of the amplified signal. A comparator module compares the detected power to a high threshold, a low threshold and a target threshold intermediate the high and low thresholds. A controller module changes the gain of the VGA so as to drive the detected power in a direction toward the middle threshold when the comparator module indicates the detected power is not between the high and low thresholds.
Abstract:
The present invention provides an amplifying apparatus including, two amplifiers for receiving input signals in common and for outputting their respective amplified signals, a combiner for combining the output signals of the two amplifiers and for outputting a combined signal, the amplifying apparatus which inhibit the distortion component in the output of amplifiers in the transition state. This amplifying apparatus comprises, a predistortion unit for determining a distortion compensation component based on the output of the combiner and for predistorting the input based on the determined distortion compensation component, and a gain control unit for attenuating the inputs to set lower than in the steady state by reducing the gain in the transition from two amplifier operation to one amplifier operation, or in the transition from one amplifier operation to two amplifier operation, or at the time of removal or attachment the amplifiers.
Abstract:
A Variable Gain Amplifier (VGA) amplifies an input signal according to a gain, to produce an amplified signal. A detector module detects a power indicative of a power of the amplified signal. A comparator module compares the detected power to a high threshold, a low threshold and a target threshold intermediate the high and low thresholds. A controller module changes the gain of the VGA so as to drive the detected power in a direction toward the middle threshold when the comparator module indicates the detected power is not between the high and low thresholds.
Abstract:
Methods and systems for processing a plurality of signals are disclosed herein. Aspects of the method may comprise amplifying an input signal. The amplified input signal may be bandpass filtered. Amplification of the input signal may be adjusted based on only narrowband received signal strength indication of the bandpass filtered amplified input signal. The amplified input signal may be downconverted and a blocker signal may be bandpass filtered from the amplified input signal. Signal strength of a desired signal from the amplified input signal may be measured. The amplification of the input signal may be adjusted utilizing a triple well (TW) NMOS transistor. A control signal may be generated based on the narrowband received signal strength indication of the bandpass filtered amplified input signal. The amplification of the input signal may be adjusted based on at least one of the generated control signals.