RET Oscilloscope Spectrum Reconstruction Without RF Mixers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing test and measurement instruments struggle to efficiently measure high-frequency RF signals and baseband signals required for 5G and 6G wireless communications, as they require wideband capabilities and are limited by the complexity and calibration needs of traditional mixers.
Innovation Solution
A real-equivalent-time (RET) oscilloscope equipped with bandpass filters and multiple channels, capable of functioning as a wideband real-time spectrum analyzer (WSA), which reduces hardware components and complexity while enabling simultaneous measurement of RF and baseband signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional mixers are used to down-convert high RF band to lower intermediate frequency band, then the signal can be converted to sampled digital signal, but the hardware complexity and calibration needs increase
Solution Approach 1:
The patent removes the traditional mixer component from the signal path entirely. Instead of using a mixer to down-convert RF signals to intermediate frequency, the invention directly samples high-frequency RF signals using high-speed ADCs, extracting only the necessary frequency conversion function through digital processing rather than analog mixing hardware.
Solution Approach 2:
The patent replaces the mechanical/analog mixer system with a digital sampling and processing system. High-speed ADCs directly sample RF signals, and digital signal processing performs the frequency conversion that was traditionally done by analog mixers, eliminating the need for complex analog mixing hardware and its associated calibration requirements.
2Adaptability or versatility
If wideband capabilities are implemented to measure 5G and 6G wireless signals, then the instantaneous bandwidth can be increased, but the instrument complexity increases
Solution Approach 1:
The patent divides the wideband measurement capability into multiple parallel channels, each handling a specific frequency range. Multiple ADCs sample different RF bands simultaneously, and digital processing reconstructs the complete wideband spectrum, achieving wideband capability through segmented parallel processing rather than a single complex wideband path.
Solution Approach 2:
The patent creates a universal measurement platform that can handle both wired backhaul signals and wireless fronthaul signals with the same hardware architecture. The system uses identical high-speed sampling and digital processing for different signal types and frequency ranges, eliminating the need for separate specialized hardware for different measurement functions.
3Adaptability or versatility
If multiple ADCs are used to sample different RF bands simultaneously, then the measurement coverage is improved, but the spectrum reconstruction complexity increases
Solution Approach 1:
The patent uses feedback mechanisms in the spectrum reconstruction process where the system continuously adjusts the combined spectrum based on overlap and gap analysis. The digital processing monitors the output from multiple ADCs and dynamically adjusts the reconstruction algorithm to account for frequency band overlaps and gaps, ensuring accurate continuous spectrum reconstruction.
Solution Approach 2:
The patent transitions from analyzing signals in the time domain separately for each ADC channel to combining them in the frequency domain. By transforming the problem to another dimension (frequency domain), the system can easily merge spectra from multiple ADCs using FFT-based processing, simplifying the reconstruction of wideband signals compared to time-domain methods.
Data Source
AI summary
A test and measurement instrument includes one or more channels to receive a signal under test, each channel comprising an input port, a filter, and a sampler, at least one analog-to-digital converter (ADC), the at least one ADC having two pipes connected to the sampler of one of the one or more channels, the at least one ADC to produce digital samples of the signal at a sample rate, and one or more processors configured to execute code that causes the one more processors to acquire a spectrum of the digital samples for each pipe in the at least one ADC, and use the spectrums of the digital samples for each pipe in the at least one ADC to reconstruct the spectrum of the signal under test. A method of operating a test and measurement instrument, and a method a method of calibrating a test and measurement instrument is included.