Nokia Telecommunications Oy

Nokia Networks Oy

Nokia Corporation

Jukka-Pekka Neitiniemi

Chia-sam Wey

Kim Anh Tran

Steven J Laureanti

Russ Michaud

Kari Saukko

A transmitter circuit and method for transmitting a data signal at a desired transmitter power level. The transmitter circuit includes an attenuator for attenuating the data signal by an attenuation factor. An external amplifier receives the attenuated signal and amplifies the signal to an amplified signal voltage. A storage unit containing a set of calibrated power levels associated to a set of amplifier voltages provides a calibrated power level based on the amplified signal voltage. A controller is configured to modify the attenuation factor of the attenuator in response to the difference between the calibrated power level and the desired transmitter power level.

Distributed power level control system of transmitter for cellular communication

A compensated RF power detector utilized in power control circuits for preventing power amplifier saturation. A power amplifier uses a power control circuit to maintain the power amplifier as efficiently and linearly as possible without distortion. The operating point of the power amplifier is defined as close to the 1 dB gain compression point as possible for maximum efficiency and linearity with minimum distortion. However, extreme temperature conditions affect the 1 dB gain compression point causing the power amplifier to operate too close to saturation resulting in distortion or spectral growth. In an embodiment, the compensated RF power detector comprises a RF power detector and a variable RC circuit. The RF power detector has a RF input for receiving RF power, a detector output for supplying a compensated detected voltage and, a detecting diode for generating a detected voltage in response to the received RF power. The detecting diode has an anode coupled to the RF input and a cathode coupled to the detector output. The variable RC circuit comprises a capacitor and a control circuit. The capacitor has a first lead coupled to the cathode of the detecting diode and a second lead coupled to the control circuit. The control circuit has a control output containing a varying resistance coupled to the second lead of the capacitor. The variations in the varying resistance result in the compensation of the detected voltage.

Compensated RF power detector

A temperature compensated variable attenuator comprising a variable attenuator having at least one diode with temperature variations across the at least one diode producing a temperature offset signal. A bias source coupled to the variable attenuator supplies a biasing signal to the at least one diode through a temperature compensation source. The temperature compensation source is coupled between the bias source and the variable attenuator with the temperature compensation source comprising at least one diode capable of producing a temperature offset signal approximately equivalent to the temperature offset signal produced by the first at least one diode. The approximate temperature offset signal subtracted from the biasing signal produces a temperature compensated bias signal that is supplied to the variable attenuator.

Temperature compensated variable attenuator

A precision-controlled logarithmic amplifier having reduced interference parameters. In an embodiment, the invention comprises a logarithmic amplifier having an output signal providing a logarithmic representation of an input signal. A precision-control circuit is coupled to the logarithmic amplifier. The precision-control circuit produces a bias and a saturation current that act to reduce the effects of bias and saturation currents that are produced in the logarithmic amplifier and affect the output signal of the logarithmic amplifier.

Precision-controlled logarithmic amplifier

A controlled detector circuit for generating a detector current to the input of a selected circuit. An unwanted operational voltage is generated on the input of the selected circuit affecting the precision of the detector circuit. The controlled detector circuit comprises a detector circuit having an RF input for detecting a RF signal and a detector output for providing the detector current. Operation of the detector circuit generates a voltage drop affecting the precision of the detector current. A control circuit having a control output connected to the detector output generates a control voltage for reducing the unwanted parameters affecting the precision of the detector current.

Precision controlled RF power detector circuit

Apparatus, and an associated method, shields separate component portions of an electronic device housed at a housing from electromagnetic interference generated during operation of the electronic device. Assembly of the apparatus which shields such component portions from one another is effectuated by lowering the component portions in a single in-line direction thereby to facilitate automated assembly.

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Irving, TX, United States of America

Jukka-Pekka Neitiniemi