RF Receive Circuit With Coupled Gain Paths for Wide-Range Switching
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Solution Overview
Problem
Existing radio frequency receive circuits are limited in their application scope due to the inability to perform wide-range gain switching between high and low gains, which affects signal-to-noise ratio and linearity performance.
Innovation Solution
A radio frequency receive circuit incorporating a coupling circuit, gain adjustment circuit, and dual balanced frequency mixer to selectively amplify or attenuate gains, enabling wide-range switching and improving signal-to-noise ratio and linearity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If only an amplification unit is used to amplify the radio frequency signal, then the circuit structure is simple, but the circuit cannot implement wide-range switching between high gain and low gain
Solution Approach 1:
The coupling circuit divides the input radio frequency signal into multiple signal paths (e.g., direct path and coupled path). Each path can be independently processed with different gain levels, enabling wide-range gain switching while maintaining manageable circuit complexity through modular segmentation.
Solution Approach 2:
The coupling circuit serves multiple functions: it acts as a signal splitter, provides different gain levels through selective coupling, and enables both high-gain and low-gain modes. This multi-functionality achieves wide-range adaptability without proportionally increasing circuit complexity.
2Measurement precision
If the radio frequency receive circuit uses fixed gain amplification, then the circuit structure is simple, but the signal-to-noise ratio cannot be optimized for varying signal energy levels
Solution Approach 1:
The coupling circuit provides dynamic gain adjustment by selectively activating different coupling paths based on the input signal energy level. This dynamic adaptation optimizes the signal-to-noise ratio for varying signal conditions without requiring complex programmable gain amplifier structures.
Solution Approach 2:
The circuit changes the gain parameter by selecting between different coupling paths with inherent different gain levels. This parameter change approach enables signal-to-noise ratio optimization across varying signal energy levels while avoiding the complexity of continuously adjustable gain mechanisms.
3Adaptability or versatility
If a single amplification mode is used, then the circuit design is simple, but the application scope is limited due to inability to handle different signal energy ranges
Solution Approach 1:
The coupling circuit segments the signal processing into multiple paths with different gain characteristics. This segmentation enables the circuit to handle different signal energy ranges by selecting appropriate paths, expanding application scope while keeping each segment relatively simple.
Solution Approach 2:
The coupling circuit acts as an intermediary that mediates between the input signal and the subsequent processing stages. It provides intermediate gain adjustment capabilities that expand the circuit's application scope without requiring complex direct control mechanisms between the signal source and processing units.
Data Source
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AI summary
This application provides a radio frequency receive circuit, a receiver, and an electronic device, to reduce interference of noise to a first voltage signal, improve a signal-to-noise ratio of the first voltage signal, and implement wide-range switching between a high gain and a low gain of a second radio frequency signal through a gain adjustment circuit, thereby expanding an application scope of the radio frequency receive circuit. The radio frequency receive circuit may include a coupling circuit, the gain adjustment circuit, and a dual balanced frequency mixer. The coupling circuit may be configured to: convert a first radio frequency signal into at least two second radio frequency signals, and output the at least two second radio frequency signals to the gain adjustment circuit. The gain adjustment circuit may be configured to: selectively amplify or attenuate a gain of each second radio frequency signal, and output at least two third radio frequency signals to the dual balanced frequency mixer. The dual balanced frequency mixer may be configured to mix the at least two third radio frequency signals based on a local oscillation signal.