Time-Interpolated ADC Architecture for Direct RF Sampling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Analog-to-digital converters for direct radio-frequency sampling receivers face challenges in operating at high speeds without the need for mixers or local oscillators, requiring innovative solutions to efficiently convert high-frequency analog signals into digital codes.
Innovation Solution
The proposed solution involves an analog-to-digital converter with first and second comparators and an interpolation comparator, which receive input signals and comparison signals to generate outputs based on relative timing, allowing for high-speed operation without a mixer, using differential comparators and time-based interpolations integrated into an integrated circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If traditional mixers and local oscillators are used in direct radio-frequency sampling receivers, then signal conversion can be achieved, but device complexity and power consumption increase
Solution Approach 1:
The patent removes the mixer and local oscillator from the direct radio-frequency sampling receiver architecture. By extracting these traditional components, the system achieves signal conversion directly through the analog-to-digital converter using time-interpolation techniques, thereby reducing device complexity while maintaining conversion capability
Solution Approach 2:
The patent replaces the mechanical/mixed-signal approach of traditional mixers with a digital time-interpolation method. The analog input signal is directly sampled and converted to digital codes through a series of comparators and time-interpolation logic, substituting the traditional mixer-based frequency conversion mechanism
2Use of energy by stationary object
If traditional mixers and local oscillators are used, then signal conversion is achieved, but power consumption increases
Solution Approach 1:
The patent extracts and removes the power-hungry mixer and local oscillator components from the receiver architecture. The remaining system achieves signal conversion through low-power comparators and digital logic implementing time-interpolation, significantly reducing overall power consumption while maintaining conversion functionality
Solution Approach 2:
The patent employs simple, low-power comparators and digital logic elements instead of complex, power-intensive mixer circuits. These simpler components consume less power and can be implemented efficiently in integrated circuit form, reducing the power budget while achieving the same conversion function
3Productivity
If high-speed operation is required without mixers, then hardware is reduced, but measurement precision of timing must be increased
Solution Approach 1:
The patent segments the timing measurement process into multiple coarse time bins using parallel comparators with different reference signals. By dividing the time domain into discrete intervals and using multiple comparators to detect which interval the input signal falls into, the system achieves high timing precision through segmentation rather than requiring a single high-precision measurement
Solution Approach 2:
The patent transforms the timing measurement problem from a single-dimensional continuous measurement into a multi-dimensional discrete classification problem. By using multiple comparators with different reference levels and combining their outputs through time-interpolation logic, the system measures time position in multiple dimensions, achieving high precision through dimensional expansion
Data Source
AI summary
An analog-to-digital converter has first and second comparators and an interpolation comparator. The first comparator receives an input signal and a comparison signal, and generates an output as a function of the input signal and the comparison signal. The second comparator receives the input signal and a second comparison signal (different from the first comparison signal), and generates a second output as a function of the input signal and the second comparison signal. The interpolation comparator, operatively connected to the first and second comparators, receives the first and second outputs, and generates a third output based on relative timing of the first and second outputs.