Difference Bitmap Signal Detection in Spectrum Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional test and measurement instruments, such as real-time spectrum analyzers, face difficulties in detecting very small density variations in the presence of high density signals, making it challenging to observe small interference signals within the same frequency range.
Innovation Solution
A test and measurement instrument that converts digital data into bitmaps and subtracts one bitmap from another to produce a difference bitmap, revealing small density variations by isolating density differences, which can be displayed or used to generate a trigger signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional DPX spectrum display is used to show high density signals, then the display can show the presence of signals, but very small density variations (low density signals) cannot be discerned in the presence of large density values
Solution Approach 1:
The patent extracts only the density differences between two bitmaps by subtracting one bitmap from another. This extraction operation isolates the small density variations from the large density values, removing the masking effect and allowing low density signals to be detected independently of high density signals.
Solution Approach 2:
The patent changes the parameter being displayed from absolute density values to density differences. By computing the difference between two bitmaps (representing different time periods or conditions), the display shows only changes in density, making small variations detectable even in the presence of large absolute density values.
2Measurement precision
If the difference bitmap is computed by subtracting one bitmap from another, then small density variations can be detected, but the computational complexity and processing time increase
Solution Approach 1:
The patent uses bitmaps as simplified copies or representations of the signal data. Instead of processing the full complex signal waveforms, it creates bitmap representations that capture only the essential density information. This copying approach reduces computational complexity while maintaining the ability to detect density variations.
Solution Approach 2:
The patent segments the signal analysis into discrete bitmap representations divided into manageable units. By working with segmented bitmap data rather than continuous complex signals, the computational burden is reduced while still enabling detection of density differences through simple subtraction operations.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A test and measurement instrument converts digital data that represents an input signal into a plurality of bitmaps, and then subtracts one of the bitmaps from another one of the bitmaps to produce a difference bitmap. The difference bitmap does not contain density values that are common to the two bitmaps, but instead only contains the density differences between the two, thereby revealing very small density variations in the presence of large density values. In some embodiments, the difference bitmap is displayed on a display device. In other embodiments, the difference bitmap is used to generate a trigger signal.