Reconfigurable IF Filter Tuning for Multi-Format Signal Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional signal receiving devices face challenges in adapting to multiple modulation rates and methods without increasing chip area, as they require multiple IF filtering circuits, which lead to increased chip area and errors due to production variations, and adjusting filter passband or center frequency affects noise levels and optimal filter settings.
Innovation Solution
A signal receiving device and method that utilize a mixer to generate an intermediate frequency signal, an IF filter with adjustable frequency band and center frequency, and a controlling part to adjust these parameters dynamically, allowing for optimal filtering without increasing chip area by using a single IF filter with adjustable condenser and resistance values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple IF filtering circuits are installed to receive different RF signal formats, then the device can adapt to multiple modulation rates and methods, but the chip area increases
Solution Approach 1:
The patent implements a single IF filtering circuit that can be dynamically reconfigured to perform multiple filtering functions for different RF signal formats. The controlling part adjusts the filter constants (resistance and capacity values) based on the detected signal format, enabling one circuit to replace multiple dedicated circuits, thereby reducing chip area while maintaining adaptability to various modulation rates and methods
Solution Approach 2:
The patent employs dynamic adjustment of filter constants (resistance and capacity values) in the IF filtering circuit based on the detected RF signal format. This dynamic reconfiguration allows the same hardware circuit to adapt its characteristics for different signal types, eliminating the need for multiple static filtering circuits and reducing overall chip area
2Reliability
If the filter passband is designed to be large in advance to handle production variations, then the design target value can be dealt with even if there is deviation, but noise is increased
Solution Approach 1:
The patent adjusts the filter constants (resistance and capacity values) dynamically based on the detected signal format and actual production variations. This allows the filter passband to be optimized for each specific signal type rather than designed conservatively large, thereby maintaining reliability across production variations while minimizing noise for each operating condition
3Manufacturing precision
If the filter passband is adjusted by changing resistance or capacity value, then the filter characteristics can be optimized, but the center frequency changes simultaneously causing separation from original IF frequency
Solution Approach 1:
The patent separates the control of filter passband and center frequency by using different circuit elements: resistance values are adjusted to optimize the filter passband, while capacity values are adjusted to correct center frequency deviations. This segmentation of control functions allows independent optimization of passband characteristics and center frequency accuracy without mutual interference
Solution Approach 2:
The patent implements a feedback mechanism where the controlling part detects the actual center frequency and passband characteristics, compares them with target values, and adjusts the resistance and capacity values accordingly. This closed-loop control ensures that filter optimization maintains accurate center frequency alignment with the original IF frequency
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
Enables the device to pass desired frequency components of the intermediate frequency signal without increasing chip area, compensating for production variations and achieving optimal filter characteristics by adjusting frequency band and center frequency, thereby reducing noise and improving performance.
Implementation Method 1
an IF filtering circuit is equipped to receive an RF signal, and generate an IF signal of an intermediate frequency by mixing the RF signal and a local oscillating signal
Data Source
AI summary
A signal receiving device and signal receiving method to pass a desired frequency component of an intermediate frequency signal by using an IF filter without increasing a chip area. The signal receiving device comprises: a mixer to mix a received frequency signal with a local oscillation frequency signal to generate an intermediate frequency signal; an IF filter to pass a predetermined frequency component of the intermediate frequency signal; a controlling part which adjusts, according to a frequency band of the intermediate frequency signal, the frequency band of the IF filter, and adjust, according to a center frequency set in the IF filter that fluctuates with the adjustment, a center frequency of the intermediate frequency signal to be inputted in the IF filter; and a demodulating part to demodulate a frequency component of the intermediate frequency signal outputted after passing through the IF filter.