RF Oscillator Phase Noise Capture for Digital Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radio frequency circuits, particularly those using variable frequency oscillator systems, suffer from phase noise that degrades radio performance, and existing solutions to mitigate this issue often require expensive and bulky high-specification components.
Innovation Solution
A radio frequency circuit that includes a phase noise capture circuit to digitally process and compensate for phase noise in the output of a variable frequency oscillator system, using a digitiser and optionally a fixed frequency oscillator to generate a digitised signal, allowing for the use of lower quality oscillator systems and subsequent digital correction of phase noise effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high-specification components are used to reduce phase noise, then radio performance is improved, but cost and device size increase
Solution Approach 1:
The patent extracts the phase noise from the main signal path by using a separate capture circuit that mirrors the signal path to isolate and measure phase noise independently. This allows the main variable frequency oscillator to be of lower specification while the captured phase noise is compensated digitally, resolving the contradiction between using high-spec components and reducing device complexity
Solution Approach 2:
The patent replaces the mechanical/analog approach of using high-specification physical components to reduce phase noise with a digital signal processing approach. By capturing phase noise and applying digital compensation algorithms, the system achieves improved radio performance without requiring expensive and bulky high-specification oscillator components
2Object-affected harmful factors
If high-specification components are used to reduce phase noise, then phase noise is reduced, but weight and volume increase
Solution Approach 1:
The patent creates a copy of the signal path through the capture circuit to measure and capture phase noise without affecting the main signal flow. This copied measurement is then used for digital compensation, allowing phase noise reduction without requiring heavy high-specification components in the main path
3Ease of manufacture
If digital processing is used to compensate phase noise, then component cost is reduced, but processing complexity increases
Solution Approach 1:
The patent introduces a capture circuit as an intermediary that bridges the analog signal path and the digital processing domain. This intermediary captures the phase noise characteristics and translates them into a form suitable for digital compensation, managing the complexity transition between analog and digital domains
Data Source
AI summary
A radio frequency circuit for processing a radio frequency signal. The circuit comprises a variable frequency oscillator system and a radio frequency signal processing circuit arranged to process a radio frequency signal using the output of the variable frequency oscillator system. A digitiser is arranged to receive the output of the radio frequency signal processing circuit and generate a digitised signal. A phase noise capture circuit is arranged to capture the phase noise in the output of the variable frequency oscillator system. The radio frequency circuit is arranged to compensate for the effect of the phase noise in the output of the variable frequency oscillator system on the output of the radio frequency signal processing circuit, by digitally processing the digitised signal generated by the digitiser using the output of the phase noise capture circuit.