RF Mixer Transconductance Linearization With Scaled Output Current
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radio front end circuitry faces challenges in linearizing the voltage-to-current relationship, which compromises output current magnitude, making it difficult to meet requirements in applications needing higher current while maintaining linearity.
Innovation Solution
The proposed solution involves a mixer circuit with a transconductance block that includes degeneration resistors and feedback circuit paths with active components to linearize the voltage-to-current relationship, producing a scaled and amplified current that satisfies both linearity and current magnitude requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If linearization techniques are applied to the transconductance block, then the voltage-to-current linearity is improved, but the output current magnitude is reduced
Solution Approach 1:
The transconductance block is divided into multiple parallel transconductance paths, each with its own degeneration resistor. This segmentation allows the circuit to achieve linearization through the combined effect of multiple paths while maintaining higher output current capacity compared to a single linearized path.
Solution Approach 2:
The invention changes the parameter configuration by using multiple degeneration resistors with different resistance values in parallel paths. This parameter variation allows optimization of both linearity (through the degeneration effect) and current magnitude (through parallel paths with lower individual resistance values), resolving the traditional tradeoff.
2Quantity of substance
If multiple parallel transconductance paths with different degeneration resistors are used, then output current capacity is increased, but circuit complexity increases
Solution Approach 1:
Multiple transconductance paths are merged into a single integrated circuit block with shared components such as the current source and output node. This merging approach increases current capacity through parallel paths while minimizing the increase in overall circuit complexity by sharing common elements.
Solution Approach 2:
The multiple transconductance paths serve multiple functions simultaneously: they provide current amplification, voltage-to-current conversion, and linearization. The degeneration resistors in each path contribute to both current control and linearity improvement, making the circuit elements multi-functional and reducing the need for separate dedicated components.
Data Source
AI summary
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.