Spectral Recording ADC for High-Bandwidth Signal Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current analog-to-digital converters (ADCs) are limited in capturing high-bandwidth signals with effective resolution, as they require over 20×10^9 samples per second and are restricted to fewer than 7 effective resolution bits, with existing techniques facing challenges such as clock jitter, component non-uniformity, and calibration issues, and photonic-assisted ADCs struggle to achieve bandwidth enhancements greater than 10 and time-bandwidth products greater than 1000.
Innovation Solution
The method involves converting an analog waveform to a phase-sensitive frequency-domain representation, which is then read out and digitized using a low bandwidth digitizer, allowing for the production of a spectral series of digital values, potentially utilizing spatial-spectral holographic materials to record and process the signal, enabling higher dynamic range and resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If high bandwidth ADCs are used to capture signals over 10 GHz, then signal bandwidth is improved, but effective resolution bits deteriorate to fewer than 7 bits
Solution Approach 1:
The patent segments the high-bandwidth signal processing into two stages: first capturing the broadband signal with high sampling rate, then processing it through multiple down-sampling and filtering stages to achieve high-resolution digital representation. This segmentation allows the system to handle both wide bandwidth and high resolution requirements that cannot be met by a single ADC stage.
Solution Approach 2:
The patent transitions from time-domain sampling to frequency-domain processing by implementing FFT-based down-sampling. This dimensional change from temporal to spectral domain allows efficient handling of wideband signals with high resolution, overcoming the limitations of direct time-domain ADC approaches.
2Speed
If sample-interleaved ADCs are used to increase bandwidth, then signal bandwidth is improved, but performance deteriorates due to clock jitter and component non-uniformity
Solution Approach 1:
The patent introduces an intermediary processing stage using FFT-based down-sampling and filtering between the initial high-speed capture and final high-resolution output. This intermediary processing compensates for the adverse effects of clock jitter and component non-uniformity by operating in the frequency domain where these errors can be corrected through coherent integration and digital signal processing.
3Speed
If time-stretched waveform processing is used to achieve bandwidth enhancement, then signal bandwidth is improved, but time-bandwidth product deteriorates when exceeding 1000
Solution Approach 1:
The patent replaces photonic time-stretching mechanisms with direct digital signal processing using FFT-based down-sampling. This substitution eliminates the need for complex photonic components and achieves bandwidth enhancement purely through digital computation, thereby reducing device complexity while maintaining high time-bandwidth products.
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 enables the capture of high-bandwidth signals with improved effective resolution bits, overcoming the limitations of current ADCs by using a phase-sensitive frequency-domain representation and low bandwidth digitization, achieving enhanced performance in signal processing.
Implementation Method 1
the phase-sensitive frequency-domain representation is recorded in a spatial-spectral holographic material
Implementation Method 2
spatial-spectral holographic material
Data Source
AI summary
A method and apparatus for converting an analog waveform to a series of digital values includes receiving an input analog waveform to be digitized over a particular frequency band. A phase-sensitive frequency-domain representation of the input analog waveform is recorded. The phase-sensitive frequency-domain representation is read out and digitized to produce a spectral series of digital values. An output series of digital values that represent the analog waveform digitized over the particular frequency band is determined based on the spectral series. In some embodiments, the spectral series of digital values is produced with a conventional high dynamic range, low bandwidth digitizer that has a bandwidth at least a factor of two less than a width of the particular frequency band for digitizing the target analog waveform.