Beamforming Failure Detection in 5G mmWave Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G wireless networks, especially those utilizing massive MIMO, there is a challenge in efficiently detecting and recovering from beamforming failures, which can lead to unreliable communication due to the complexity of managing multiple communication beams and the need for effective spectrum utilization in both licensed and unlicensed frequency ranges.
Innovation Solution
The implementation of an access node (AN) that schedules multiple reference signals over downlink communication beams, employing a Listen Before Talk (LBT) procedure to identify free spectrum channels and adaptively transmit these signals, while ignoring scheduled transmissions during occupied periods, ensuring reliable beamforming by monitoring block error rates and initiating beam failure recovery procedures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple reference signals are scheduled over multiple downlink communication beams, then beamforming reliability is improved through failure detection and recovery, but device complexity increases due to the need to manage multiple beams and implement LBT procedures
Solution Approach 1:
The patent segments the beam management process into distinct phases: reference signal transmission, LBT procedure execution, failure detection, and beam recovery. This segmentation allows the complex task of managing multiple beams to be handled through systematic, manageable steps, reducing the cognitive load on the system while maintaining reliability
Solution Approach 2:
The patent implements feedback mechanisms where the access node monitors beam quality and block error rates, and the UE reports beam failure conditions. This feedback loop enables dynamic adjustment of beam selection and transmission scheduling, improving reliability through continuous optimization while providing structured information flow that manages complexity
2Productivity
If LBT procedure is performed to monitor spectrum availability, then spectrum utilization efficiency is improved, but transmission time is reduced when spectrum is occupied by other transmissions
Solution Approach 1:
The patent applies preliminary action by having the access node perform LBT procedure before scheduling reference signal transmissions. This advance spectrum checking ensures that transmission opportunities are identified in advance, allowing the system to maximize spectrum utilization efficiency while preparing transmission timing to minimize losses when spectrum becomes available
Solution Approach 2:
The patent implements periodic LBT procedures and scheduled transmission opportunities. By using periodic checking and structured transmission windows, the system balances spectrum monitoring overhead with transmission time requirements, allowing efficient spectrum sharing while maintaining reliable communication within the allocated time frames
3Productivity
If multiple transmissions are scheduled over multiple beams, then communication capacity is improved, but reliability deteriorates when LBT fails and transmissions must be ignored
Solution Approach 1:
The patent applies dynamics by making the transmission schedule adaptable rather than fixed. When LBT fails, the system dynamically adjusts by ignoring affected transmissions and re-scheduling for subsequent opportunities. This dynamic approach allows the system to maintain high communication capacity through multiple beam opportunities while ensuring reliability by only transmitting when spectrum conditions permit
4Reliability
If beam failure detection and recovery procedures are implemented, then communication reliability is improved, but processing time increases due to additional detection and recovery operations
Solution Approach 1:
The patent applies preliminary action by continuously monitoring beam quality metrics and preparing recovery procedures in advance. The access node pre-configures multiple reference signal transmissions and beam options, so when failure is detected, the recovery process can begin immediately without significant processing delay, thus improving reliability while minimizing time loss
Solution Approach 2:
The patent ensures continuity of useful action by maintaining ongoing beam monitoring and keeping multiple backup beams ready. The detection and recovery operations are integrated into the continuous transmission process rather than being separate interruptions, allowing the system to maintain communication reliability while minimizing processing time through seamless failure recovery
Data Source
AI summary
Beam determination refers to a set of procedures for an access node (AN) and a user equipment (UE) to select from among downlink communication beams and/or uplink communication beams for downlink and/or uplink communications, respectively. Often times, the downlink communication beams can include one or more downlink control channels, for example, a Physical Downlink Control Channel (PDCCH) and/or a Physical Downlink Shared Channel (PDSCH), to provide downlink reference signals, such as channel-state information reference signals (CSI-RSs), to the UE. The AN can execute various exemplary downlink beam scheduling procedures to control the transmission of the downlink reference signals, such as the CSI-RSs to provide an example, over the downlink communication beams. In some embodiments, the UE can utilize the CSI-RSs to perform beamforming failure detection (BFD) and beamforming failure recovery (BFR) in the wireless networks.