Asymmetric Transmission Line Combiner for Equal-Loss MIMO Paths
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Symmetric transmission line power combiners used in MIMO transceivers with a large number of transmit power outputs occupy significant die area and experience high attenuation loss, requiring additional amplifier stages and increased power consumption.
Innovation Solution
Implementing an asymmetric transmission line power combiner with progressive width scaling of switches and controlled activation of transmit power outputs to equalize attenuation loss among multiple paths, reducing die area and overall attenuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a symmetric transmission line power combiner is used to combine multiple transmit power outputs, then all paths have equal attenuation loss, but the die area increases significantly and overall attenuation loss increases
Solution Approach 1:
The patent applies asymmetry by using transmission lines with different physical lengths but designing them to have equal electrical lengths at the operating frequency. The asymmetric physical layout allows compact integration while maintaining equal signal attenuation across all combiner paths through careful impedance and length matching
Solution Approach 2:
The patent implements local quality by adjusting specific parameters (length, width, impedance) of individual transmission line segments to compensate for their different physical paths. Each transmission line is locally optimized so that despite asymmetric routing, all paths present equal electrical characteristics and attenuation at the combining point
2Stability of the object's composition
If a symmetric transmission line power combiner is used to combine multiple transmit power outputs, then all paths have equal attenuation loss, but additional amplifier stages are required increasing power consumption
Solution Approach 1:
The asymmetric design with optimized transmission line lengths reduces the maximum path length required in symmetric designs. This reduction in transmission line length directly decreases overall attenuation loss, allowing the system to operate without additional amplifier stages and thereby reducing power consumption
Solution Approach 2:
The patent changes the physical parameters (length, width, impedance) of transmission lines to optimize the combiner performance. By adjusting these parameters, the design achieves equal attenuation across paths with shorter overall transmission line length, reducing the need for signal boosting and associated power consumption
3Stability of the object's composition
If switches with different impedances are used in asymmetric positions, then attenuation loss is equalized among paths, but impedance matching becomes more complex
Solution Approach 1:
The patent applies local quality by assigning specific impedance values to switches based on their position in the asymmetric combiner. Each switch is locally optimized with an impedance tailored to its specific location, allowing equal attenuation across all paths while managing impedance matching through systematic local adjustments rather than global complexity
Data Source
AI summary
An example device described herein includes a first pad, a second pad, and a transmission line including a first end configured to couple to monitor circuitry, wherein the transmission line includes a second end. The example device also includes a first switch coupled to the first pad, wherein the first switch is coupled to the transmission line between the first end and the second end. The example device further includes a second switch coupled to the second pad and to the second end of the transmission line, wherein an impedance of the first switch is higher than an impedance of the second switch.