Butler Matrix End-Fire Array for 60-GHz Chip-to-Chip Beam Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multicore multichip computing systems face challenges in achieving efficient and reconfigurable interchip communication due to wiring complexity, with existing antenna arrays lacking seamless connectivity and high radiation efficiency, especially at mmW frequencies where beamforming using solid-state phase shifters is impractical.
Innovation Solution
A compact antenna module with a Butler matrix and circular patch antenna elements for 360° end-fire scanning, integrated with a chip-to-chip 60-GHz 2×2 circular patch planar antenna array, enabling seamless reconfigurable interchip communication through a hybrid space-surface wave link, utilizing a 2-D Butler matrix in microstrip form for efficient beam switching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If traditional wired interconnects are used for chip-to-chip communication, then wiring complexity is reduced, but power dissipation and signal delay increase significantly
Solution Approach 1:
The patent replaces traditional mechanical/wired interconnects with wireless mmW antenna arrays integrated on CMOS chips. This substitution eliminates physical wiring between chips, reducing wiring complexity while simultaneously lowering power dissipation and signal delay through electromagnetic wave transmission in the 57-65 GHz band
2Adaptability or versatility
If solid-state phase shifters are used for beamforming at mmW frequencies, then beam switching capability is achieved, but device complexity and power consumption increase
Solution Approach 1:
The patent segments the beamforming function into simple on-chip RF switches that select between multiple fixed beam patterns generated by the antenna array. Instead of using complex solid-state phase shifters for continuous beam control, the system divides the beamforming task into discrete selectable patterns, reducing device complexity while maintaining adaptability for interchip communication
Solution Approach 2:
The patent implements dynamic beam switching through RF switches that can rapidly change the active beam pattern based on communication requirements. This dynamic reconfiguration capability allows the system to adapt to different spatial channels and maintain optimal communication links without the complexity of continuous phase adjustment mechanisms
3Loss of energy
If antenna arrays are integrated on-chip for wireless interconnection, then power dissipation and delay are reduced, but radiation efficiency and bandwidth are limited
Solution Approach 1:
The patent optimizes antenna array parameters including element geometry, spacing, and feeding networks to achieve broadband operation in the 57-65 GHz band. By carefully controlling these parameters, the system achieves both low power dissipation through integrated on-chip implementation and high radiation efficiency through optimized electromagnetic radiation characteristics of the antenna elements
4Device complexity
If wireless interchip communication is implemented, then wiring complexity is reduced, but connectivity and integration with transceivers must be seamless
Solution Approach 1:
The patent merges the antenna array and transceiver circuits into a single integrated on-chip system. The antenna elements are directly connected to the transceiver through on-chip feeding networks, creating a seamless integrated unit that simplifies manufacturing and ensures reliable connectivity without requiring separate assembly steps or external connections
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 solution provides a compact, efficient, and reconfigurable interchip communication system with improved power coupling and reduced latency, achieving good agreement between simulated and measured transmission coefficients, and enabling dynamic reconfiguration of interchip links in multicore computing systems.
Implementation Method 1
an antenna element array and a Butler matrix. The antenna element array includes an array of n circular patch antenna elements for 360° end-fire scanning
Implementation Method 2
The Butler matrix has n/4 submatrices. Each of the submatrices include two input 90° hybrids that each have two outputs and two inputs for selectively receiving signals from a transceiver
Data Source
AI summary
A multichip system includes a plurality of processor chips each having one or more cores and a plurality of antenna module for establishing interchip wireless communication. Each antenna module is disposed on a chip. At least one antenna module includes an antenna element array and a Butler matrix. The antenna element array includes n circular patch antenna elements for 360° end-fire scanning, where n is equal to 4 or a multiple thereof. The Butler matrix has n/4 submatrices. Each submatrix include two input 90° hybrids each having two outputs and two inputs for selectively receiving signals from a transceiver. The Butler matrix also includes two output 90° hybrids each having two outputs and two inputs. The two inputs of each output 90° hybrid are coupled to an output of different ones of the input 90° hybrids. Each output of the output 90° hybrids are coupled to a different antenna element.