Broadcom Corporation

Qualcomm Incorporated

C Paul Lee

Arya Behzad

Michael Kappes

Adedayo Ojo

A radio frequency (RF) transmission correction module includes an RF transmission error detection module and a correction module. The error detection module includes an RF envelope detector, a signal conversion module, and an error detection module. The RF envelope detector is operably coupled to produce an envelope signal from a transmit RF signal, wherein the envelope signal represents at least one of local oscillation leakage and in-phase (I) and quadrature (Q) imbalance. The signal conversion module is operably coupled to convert the envelope signal into an error signal in accordance with baseband processing of the transmit RF signal. The error detection module is operably coupled to determine at least one of a local oscillation leakage value and an I and Q imbalance value from the error signal. The correction module is operably coupled to produce at least one of a local oscillation leakage correction signal and an I and Q imbalance correction signal based on the at least one of the local oscillation leakage value and the I and Q imbalance value, respectively.

RF transmission error detection and correction module

A RF differential gain stage has cross-coupled capacitors between input and output nodes of the amplifier stage to boost gain. The gain boost allows cancellation of the series resistance of an inductive load of the amplifier stage.

Gain boosting RF gain stage with cross-coupled capacitors

An scheme to provide local oscillator feedthrough offset cancellation to remove baseband and radio frequency coupled offsets. Two separate offset cancellation currents are injected at a driver which drives a baseband signal into a mixer to mix with a local oscillator signal. One offset cancellation current cancels a baseband local oscillator feedthrough offset, while the other offset cancellation current cancels a radio frequency local oscillator feedthrough offset.

Local oscillator feedthrough cancellation scheme to remove RF and baseband offsets

An offset cancellation scheme in which offset cancellation current is sourced into one differential branch of a driver circuit and sinked from the opposite differential branch. The source/sink arrangement allows for offset cancellation current to be introduced into the circuit, but the overall total average current remains substantially unchanged. When used in an I and Q mixer circuits, the offsets may be canceled without generating an I/Q imbalance in the I and Q mixers.

Mixer offset cancellation without generating I/Q imbalance

An integrated circuit radio transceiver and method therefor comprises circuitry that is operable to up-convert an outgoing continuous waveform signal to RF and that is further operable to down-convert and ingoing RF signal to one of a baseband or intermediate frequency in a manner that provides a linearized output current having an amplified current magnitude for mixing with a local oscillation in a mixer block. Specifically, a circuit portion is operable to produce a linearized current based upon an input signal. The linearized current is then produced to a current mirror block that produces a scaled and amplified output current. The scaled and amplified output current is then produced to a mixer block for mixing with a local oscillation to create the outgoing RF signal or the ingoing baseband or intermediate frequency signal.

Mixer transconductance in RF transceiver

An apparatus and method to use a gain control network across source terminals of cascode transistors that drive a differential current to control gain. The drains of the cascode transistors are coupled to a load such as a mixer. The cascode arrangement provides high impedance coupling to the load and the proximity of the gain control network allows offsets to be gain tracked to signal gain.

Mixer gain control with gain tracking offsets

An apparatus and method to use a shunt network across source terminals of cascode transistors that drive a differential current to control gain. When the gates of the cascode transistors and transistors of the shunt network are activated by a same bias voltage, the gain control is substantially independent of process, voltage and temperature variations.

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San Diego, CA, United States of America

C Paul Lee