Frequency Band Channel Location via Segmented Scanning
Solution Overview
Problem
Locating all viewable television channels in a given frequency band is a time-consuming task, as existing methods require exhaustive scanning without efficient filtering for signal detection.
Innovation Solution
A method and apparatus that set initial and secondary frequency steps to detect horizontal signals, record entrance points, and fine-tune to determine channel existence, using a tuner, video processor, audio processor, and auto frequency control to efficiently search the frequency band.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If exhaustive scanning of the frequency band is performed to locate all viewable channels, then complete channel location is achieved, but the time required increases significantly
Solution Approach 1:
The frequency band scanning process is segmented into two distinct phases: a coarse scanning phase using a first frequency step to identify potential channel regions, and a fine scanning phase using a second frequency step to precisely locate channels. This segmentation allows the system to achieve complete channel location while reducing overall search time by eliminating unnecessary fine scanning in regions confirmed to be channel-free during coarse scanning.
Solution Approach 2:
The coarse scanning phase performs preliminary action by quickly identifying regions containing horizontal synchronization signals before initiating the time-consuming fine scanning process. This preliminary identification allows the system to skip extensive searching in regions without channels, thereby reducing total search time while maintaining location completeness.
2Measurement precision
If continuous detection of horizontal signals is performed to distinguish valid channels from noise, then detection accuracy is improved, but the time required increases
Solution Approach 1:
The signal detection process is segmented into coarse detection (using first frequency step) and fine detection (using second frequency step). During coarse detection, the system quickly identifies potential signals without requiring continuous verification. Only in the fine detection phase, where precision is critical, does the system perform continuous horizontal signal detection. This segmentation reduces overall detection time while maintaining accuracy in critical regions.
Solution Approach 2:
The system applies partial action by performing continuous horizontal signal detection only in regions identified as potential channels during coarse scanning, rather than continuously monitoring the entire frequency band. This partial application of rigorous detection criteria maintains high accuracy for valid channel identification while significantly reducing the total time required compared to exhaustive continuous detection.
Data Source
AI summary
A method for searching a frequency band to locate a channel. The method includes the steps of setting an initial frequency and a first frequency step; determining a frequency point based on the initial frequency and the first frequency step; determining whether the frequency point satisfies a first condition, which is continuously detecting a horizontal signal a predetermined number of times. When the first condition is satisfied, the frequency point is recorded as an entrance point. A second frequency step based on the entrance point determines a second frequency point, wherein the second frequency step is less than the first frequency step. It is then determined if a channel exists at the second frequency point. The entrance point is recorded as the updated initial frequency for the next search. The described steps are repeated for the entire frequency band.