Available Bandwidth Sensing Using Tunable Analog Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wideband spectrum sensing methods for dynamic spectrum access are either slow and costly due to sequential scanning or power-intensive due to wideband scanning, making them unsuitable for mobile devices.
Innovation Solution
A method and apparatus using a tunable analog filter and energy detectors to determine available bandwidth by selectively filtering and detecting energy in received signals, allowing for incremental interval sizing to efficiently identify available channels without the need for high-speed, power-consuming ADCs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If sequential scan is used to determine available channels, then device cost is reduced, but sensing time increases significantly
Solution Approach 1:
The wideband spectrum is segmented into multiple sub-bands, which are then further divided into channels. The sensing process is segmented into two phases: first sensing sub-bands to identify available regions, then sensing only the channels within those available sub-bands. This segmentation reduces the total sensing time while using simple sequential scan hardware.
Solution Approach 2:
The patent performs partial sensing by first sensing only sub-bands rather than all individual channels. This partial action identifies promising regions where full channel sensing is then performed only in those areas, avoiding unnecessary sensing in occupied sub-bands and reducing overall sensing time.
2Productivity
If wideband scan is used to determine available channels, then sensing speed is improved, but power consumption and device cost increase
Solution Approach 1:
The wideband spectrum is divided into sub-bands and channels, allowing the system to use a low-speed ADC to sense sub-bands sequentially rather than requiring a high-speed ADC for simultaneous wideband sensing. This segmentation enables fast sensing performance using power-efficient, low-speed conversion.
Solution Approach 2:
The patent replaces the need for high-speed ADCs and complex wideband radio hardware with a combination of analog filtering, low-speed ADC, and intelligent sensing strategies. This substitution achieves wideband sensing capability using simpler, more power-efficient components.
3Productivity
If wideband scan is used to determine available channels, then sensing speed is improved, but device cost increases
Solution Approach 1:
By segmenting the spectrum into sub-bands and channels, the system achieves wideband sensing capability using a low-speed ADC and simple analog filters rather than expensive wideband radio hardware and high-speed ADCs, reducing device cost while maintaining sensing speed.
Solution Approach 2:
The patent uses inexpensive analog filters and low-speed ADCs instead of expensive wideband radio components. The system achieves wideband sensing functionality through software-controlled analog filtering and intelligent sensing sequences, replacing costly hardware with cheaper alternatives.
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
This approach significantly reduces the time and cost of determining available spectrum by using inexpensive and power-efficient analog filters and detectors, adapting to spectrum sparsity without requiring a priori knowledge, and is suitable for mobile devices.
Implementation Method 1
a tunable analog filter configured to selectively filter a received signal
Implementation Method 2
a detector configured to detect energy in output from the filter
Data Source
AI summary
In one embodiment, the method includes determining if a next interval of a bandwidth is available if an interval of the bandwidth preceding the next interval was determined to be available such that the next interval is larger than the preceding interval.