RF Cable Stub Multipath Channel Emulator
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Solution Overview
Problem
Traditional MIMO channel emulators are cost-prohibitive and computationally intensive due to the exponential increase in complexity and hardware requirements with the number of ports, making it challenging to implement higher-order MIMO systems effectively.
Innovation Solution
An RF-based channel emulator using off-the-shelf RF coaxial cables, splitters, and attenuators to model multipath reflections without the need for computationally intensive Digital Signal Processing Subsystems (DSPS), leveraging RF cable stubs and programmable attenuators to emulate distance and motion, thereby reducing costs and complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional DSPS-based MIMO channel emulators are used, then accurate multipath channel emulation is achieved, but system cost and complexity increase exponentially with the number of ports
Solution Approach 1:
The patent replaces the digital signal processing subsystem (DSPS) with an analog RF-based system using passive components. Instead of using complex digital computations to model multipath channels, the invention uses physical RF cable stubs, splitters, and attenuators to create the multipath effects directly in the RF domain, thereby reducing computational complexity while maintaining emulation accuracy
Solution Approach 2:
The patent employs inexpensive off-the-shelf RF components such as cable stubs, splitters, and attenuators to achieve channel emulation functionality. These simple, low-cost components replace the expensive and complex DSPS hardware, reducing the overall system cost by up to a tenth while maintaining the ability to emulate multipath channels accurately
2Reliability
If traditional DSPS-based MIMO channel emulators are used, then accurate multipath channel emulation is achieved, but hardware requirements and cost increase exponentially with the number of ports
Solution Approach 1:
The patent uses inexpensive off-the-shelf RF components including cable stubs, splitters, and attenuators to build the channel emulator. These simple, low-cost components replace the expensive DSPS hardware, reducing the overall system cost by up to a tenth while maintaining the ability to emulate multipath channels accurately across different MIMO configurations
Solution Approach 2:
The invention substitutes the complex digital signal processing hardware with a simpler analog RF-based implementation using passive components. This replacement reduces the hardware requirements and manufacturing cost while achieving the same channel emulation functionality through physical RF signal manipulation rather than computational processing
3Productivity
If higher-order MIMO systems are implemented, then data throughput and operating range improve, but emulator complexity and hardware requirements increase exponentially
Solution Approach 1:
The patent replaces the digital signal processing approach with an analog RF-based system that uses physical cable stubs and splitters to create multipath effects. This substitution avoids the exponential complexity increase that occurs with traditional DSPS-based emulators when handling higher-order MIMO systems, enabling accurate emulation of 4x4, 8x8, and other high-order MIMO configurations with manageable hardware requirements
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
The RF-based channel emulator significantly reduces costs by up to a tenth of traditional DSPS-based systems, enabling efficient emulation of multipath channels with simplified RF circuitry and eliminating the need for expensive computational logic, thus making it feasible to implement higher-order MIMO systems.
Implementation Method 1
causing multiple reflections between said impedance discontinuity and an open end of said RF cable stub so as to emulate a multipath channel
Data Source
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AI summary
A multipath channel emulation system and method are disclosed. In some aspects, the system and method allow for analog emulation of a multipath MIMO wireless channel. Such multipath channel emulation system is used for testing the ability of wireless communication devices to operate in an airlink channel characterized by multipath. In a particular aspect, an impedance mismatch or discontinuity is provided in an open-ended coaxial cable so as to cause multiple back and forth reflections between an impedance discontinuity and an open coaxial cable stub and, optionally, including a delay element to emulate a multi-cluster multipath environment. A plurality of such stub subsystems may be combined as sub-paths in a multipath channel emulator.