Multi-Cascode LNA With Switched Band-Specific Impedance Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing amplifiers struggle to efficiently match impedance across multiple frequency bands, leading to signal reflection and power loss, particularly in wireless devices operating in different frequency bands like n77 and n79.
Innovation Solution
A wireless device with a low-noise amplifier (LNA) incorporating a cascode amplifier structure and multiple impedance-matching circuits, each tailored to specific frequency bands, allowing dynamic selection based on input signal frequency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single impedance-matching circuit is used in existing amplifiers, then the device complexity is reduced, but the impedance matching performance deteriorates across multiple frequency bands, leading to signal reflection and power loss
Solution Approach 1:
The patent divides the single impedance-matching circuit into multiple separate impedance-matching circuits, each optimized for a specific frequency band (e.g., n77 and n79 bands). This segmentation allows each circuit to provide optimal impedance matching for its designated band, resolving the contradiction between matching performance and device complexity by sacrificing some complexity for significant performance improvement across multiple bands.
Solution Approach 2:
The patent implements dynamic switching between multiple impedance-matching circuits based on the operating frequency band. A control mechanism selects and activates the appropriate impedance-matching circuit corresponding to the current frequency band, enabling the amplifier to adapt its impedance matching characteristics dynamically. This resolves the contradiction by providing optimal matching for each band without requiring all circuits to be simultaneously active, thus managing complexity.
2Loss of energy
If multiple impedance-matching circuits are implemented for different frequency bands, then signal quality and power efficiency are improved, but the device complexity and circuit design difficulty increase
Solution Approach 1:
Each impedance-matching circuit is designed with local quality optimized for its specific frequency band, with component values (inductors, capacitors, resistors) tailored to the characteristics of that band. This local optimization ensures minimal power loss and maximal efficiency for signals in the designated band, resolving the contradiction by accepting increased overall circuit complexity in exchange for reduced power loss in each operating mode.
Solution Approach 2:
The amplifier system achieves multi-functionality by incorporating multiple impedance-matching circuits that can be selectively activated based on the operating frequency band. This universal design allows a single amplifier to efficiently handle multiple bands (n77, n79, and others) without requiring separate amplifiers for each band, resolving the contradiction by managing circuit complexity through intelligent multi-functionality rather than proliferation of independent systems.
Data Source
AI summary
Aspects of the disclosure include a wireless device comprising a module input to receive an input signal, a module output to provide an amplified output signal, a low-noise amplifier including an input amplification stage coupled to the input, and a plurality of output amplification stages switchably coupled to the input amplification stage, and a plurality of impedance-matching circuits, each impedance-matching circuit of the plurality of impedance-matching circuits having an input coupled to a respective output amplification stage and an output coupled to the module output.