NLTL Miniature Reflectometer Scalable Tether Heat Dissipation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current network analyzer measurements at mm-wave frequencies are hindered by bulky, heavy, and expensive equipment with excessive heat dissipation and limited physical reach, making it challenging for applications like on-wafer measurements due to the waveguide nature of components and precision machining.
Innovation Solution
A nonlinear transmission line (NLTL)-based miniature reflectometer system with a scalable tether length, which reduces heat dissipation and allows for longer tether lengths by locating heat-generating components in a thermally managed control box, enabling more compact and stable mm-wave measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If precision-machined waveguide components are used for mm-wave measurements, then measurement precision is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent replaces precision-machined mechanical waveguide components with a software-defined reflectometer system that uses standard coaxial cables and digital signal processing. The measurement function is migrated from mechanical precision components to software-based signal analysis, eliminating the need for precision machining while maintaining measurement accuracy through digital processing of reflected signals.
Solution Approach 2:
The system uses universal standard coaxial connectors and cables that can be used across multiple applications and frequency ranges, replacing specialized waveguide components that are limited to specific frequencies. This multi-functional approach allows the same hardware to serve various measurement needs without requiring precision-machined waveguide assemblies for each application.
2Measurement precision
If waveguide components are used, then measurement precision is improved, but weight and bulk increase
Solution Approach 1:
The patent substitutes heavy waveguide components with lightweight coaxial cable assemblies and a compact software-controlled reflectometer. The measurement functionality is maintained through software processing rather than mechanical waveguide structures, dramatically reducing the weight and bulk of the measurement system while preserving precision through digital signal analysis.
3Length of stationary object
If long test-port extenders are used to reach DUT, then physical reach is improved, but system performance deteriorates due to heat dissipation
Solution Approach 1:
The patent extracts the heat-generating components (power amplifiers and signal generators) from the remote test-port extender and relocates them to a thermally managed control box. This allows the extender to be made arbitrarily long without carrying heat-generating elements, eliminating the trade-off between tether length and heat dissipation. The extender becomes a simple passive transmission line rather than an active heat-generating assembly.
Solution Approach 2:
The patent introduces a thermally managed control box as an intermediary that houses the heat-generating components separately from the test-port extender. This intermediary structure allows thermal management of amplifiers and signal generators while enabling long tether lengths to the DUT, as the heat-generating components remain in the controlled box rather than along the extender length.
4Measurement precision
If modules are positioned close to DUT for on-wafer measurements, then measurement precision is improved, but ease of operation decreases due to limited physical reach
Solution Approach 1:
The patent makes the tether length dynamic and scalable, allowing the test-port extender to be adjusted to any required length to reach the DUT. This dynamic configuration enables the module to be positioned optimally for measurement precision while maintaining ease of operation through flexible tether extension, eliminating the fixed-position limitation of traditional waveguide systems.
Data Source
AI summary
A system for measuring an electrical response of a device under test (DUT) includes a reflectometer with reduced heat dissipation used with a vector network analyzer (VNA). The reflectometer is tethered to the VNA using a tether of scalable length which carries low frequencies. The reflectometer has a distributed harmonic generator including a non-linear transmission line (NLTL) for multiplying a frequency of an RF signal received from the VNA to generate a test signal having a frequency in the millimeter wave range at a test port connected to the DUT. A sampler in the reflectometer receives a local oscillator (LO) signal from the VNA and includes another NLTL for receiving the LO signal and generating pulses at a frequency in the millimeter wave range. When the test signal is transmitted to the DUT, the sampler outputs intermediate frequency signals which are transmitted to the VNA for characterization of the DUT.