Acoustic Transformer Integration for RF Out-of-Band Rejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transmitter chains in mobile communication devices face challenges in achieving proper amplification and filtering of RF signals, particularly in managing impedance mismatch and providing strong out-of-band rejection without increasing in-band insertion losses and current consumption.
Innovation Solution
Incorporating an acoustic transformer and a tunable ferroelectric network element into the transmitter chain, which integrates the transformer into the same circuitry as the acoustic filter, allowing for impedance matching and out-of-band signal cancellation through ferroelectric tuning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If traditional electromagnetic transformers are used for impedance matching and signal conversion, then the transmitter chain achieves proper signal transformation, but the device complexity and die area increase
Solution Approach 1:
The patent combines the transformer function with the acoustic filter into a single integrated acoustic device. The acoustic transformer uses mechanical acoustic impedance transformation rather than electromagnetic coupling, allowing the transformer and filter to be fabricated together on the same die using identical acoustic processes, thereby reducing device complexity and die area while maintaining impedance matching capability
Solution Approach 2:
The patent replaces the electromagnetic transformer (electromagnetic system) with an acoustic transformer (mechanical system). The acoustic transformer uses acoustic impedance transformation through mechanical means (acoustic transmission lines, resonators, or transformers) to achieve the same impedance matching and signal conversion function, enabling integration with acoustic filters and reducing overall system complexity
2Object-affected harmful factors
If out-of-band rejection is improved through additional filtering stages, then signal purity increases, but in-band insertion losses and current consumption increase
Solution Approach 1:
The patent merges the transformer and filter functions into a single acoustic device, allowing out-of-band rejection to be achieved through the integrated acoustic structure rather than separate filtering stages. This reduces the need for additional active components and power consumption while maintaining signal purity through passive acoustic filtering
Solution Approach 2:
The patent uses tunable ferroelectric capacitors to dynamically adjust the resonant frequencies and impedance characteristics of the acoustic transformer and filter. This allows optimization of out-of-band rejection for different frequency bands without requiring multiple fixed filters, reducing power consumption by avoiding the need for multiple active filtering stages
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances out-of-band rejection and simplifies the construction of the filter by integrating acoustic components, providing flexible design and reducing power consumption.
Implementation Method 1
a second acoustic transformer that provides a single-ended output signal for use by an acoustic filter
Implementation Method 2
the acoustic transformer may be tuned if ferroelectric resonators are used, which provides strong out-of-band signal cancelation
Data Source
AI summary
An acoustic transformer in a transmitter chain is disclosed. In one aspect, a differential power amplifier may produce a differential signal that is provided to a first transformer. A differential output of this first transformer is provided to an acoustic transformer that provides a single-ended output signal for use by an acoustic filter. By making the second transformer an acoustic transformer, the second transformer may be integrated into the same circuitry that forms the acoustic filter, thereby simplifying the die. Further, the acoustic transformer may be tuned if ferroelectric resonators are used, which provides strong out-of-band signal cancelation.