RF Receiver Signal Paths for Linearity Across Gain Levels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless radio frequency circuits face limitations in linearity due to off-state attenuation circuits, particularly when receiving middle gain signals, which affects signal processing and linearity, especially in receiver circuits.
Innovation Solution
A radio frequency transceiver device is designed with an auxiliary circuit comprising transformer coils and multiple matching circuits to form different signal reception channels, allowing for flexible operation and increased linearity by bypassing off-state switching elements for middle-low gain signals, and optimizing transformer turns ratios to reduce noise figure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple gain attenuation circuits are designed to cover a wide power range, then the receiver circuit can handle various signal power levels, but the linearity of the receiver circuit decreases due to off-state attenuation circuits affecting the signal path
Solution Approach 1:
The receiver circuit is divided into multiple signal paths with different gain configurations. Each path is optimized for specific signal power ranges, allowing the system to select the appropriate path based on input signal strength. This segmentation prevents off-state attenuation circuits from interfering with the active signal path, thereby maintaining linearity while covering a wide power range.
Solution Approach 2:
The system dynamically switches between different signal paths and gain configurations based on the detected signal power level. By adaptively selecting the appropriate path for middle-low gain signals versus high gain signals, the receiver maintains optimal linearity across varying input conditions while preserving versatility in power range coverage.
2Ease of operation
If off-state attenuation circuits are used in the signal path, then gain control is achieved, but signal linearity decreases due to signal swings affecting the off-state circuits
Solution Approach 1:
The harmful effect of off-state attenuation circuits on signal linearity is eliminated by extracting the signal from the conventional single path that contains off-state circuits. Instead, the signal is routed through dedicated paths where attenuation circuits remain in their ideal off-state or are completely bypassed for middle-low gain signals, thus maintaining signal linearity while preserving gain control capability.
Solution Approach 2:
An auxiliary circuit acts as an intermediary between the antenna and the main receiver circuit. This auxiliary circuit provides an alternative signal path for middle-low gain signals that bypasses the off-state attenuation circuits of the main receiver, thereby maintaining signal linearity while still enabling gain control through the auxiliary circuit's own attenuation mechanisms.
3Device complexity
If a single signal reception channel is used, then the device structure is simple, but the flexibility and linearity for different signal gain levels are limited
Solution Approach 1:
The auxiliary circuit is designed to serve multiple functions: it acts as a signal reception path for middle-low gain signals, provides an alternative route to maintain linearity, and can be integrated with the main receiver circuit for high gain signals. This multi-functionality increases adaptability without proportionally increasing device complexity.
Solution Approach 2:
The auxiliary circuit is nested within the overall receiver structure, sharing common components such as the antenna, mixer unit, and certain matching circuits with the main receiver. This nesting approach allows the system to have multiple signal paths for different gain levels while minimizing the additional complexity introduced by the auxiliary circuit.
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
The solution enhances the linearity of receiver circuits and reduces noise figure by dynamically adjusting signal paths based on signal gain, improving the overall flexibility and performance of the radio frequency transceiver device.
Implementation Method 1
The auxiliary circuit comprises a first transformer coil and a second transformer coil, where the first transformer coil is coupled between the second matching circuit and the transmitter circuit, and the second transformer coil is coupled to the mixer unit
Data Source
AI summary
A radio frequency transceiver device includes an antenna unit, a first matching circuit, a receiver circuit, a second matching circuit, a transmitter circuit, and an auxiliary circuit. The receiver circuit includes a mixer unit. The auxiliary circuit includes a first transformer coil and a second transformer coil. The first matching circuit and the receiver circuit are configured to form a first signal reception channel to receive, process, and transmit the first radio frequency signal to the mixer unit when the first radio frequency signal is a high gain radio frequency signal. The second matching circuit and the auxiliary circuit are configured to form a second signal reception channel to receive, process, and transmit the first radio frequency signal to the mixer unit when the first radio frequency signal is a middle-low gain radio frequency signal. Another radio frequency signal transceiver device further includes a third matching circuit.