Base Station Beamforming Calibration Error Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in achieving accurate calibration of phase and amplitude at antennas in base stations, leading to performance issues such as incorrect beamforming and reduced coverage in high-frequency bands like those used in 5G networks.
Innovation Solution
The proposed solution involves mechanisms to mitigate phase and amplitude calibration errors by modifying the antenna array size, transmission power levels, and beam codebooks at the base station side, utilizing feedback from user equipment to adjust these parameters dynamically.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If more antennas are used in the same physical aperture to take advantage of higher frequencies, then beamforming gain is improved, but calibration accuracy deteriorates due to increased phase and amplitude mismatches
Solution Approach 1:
The system performs preliminary calibration procedures to establish baseline phase and amplitude relationships between antennas before beamforming operations. Calibration reference signals are transmitted and received to pre-determine correction factors that compensate for hardware mismatches, enabling accurate beamforming with multiple antennas
Solution Approach 2:
The system implements feedback mechanisms where calibration performance is continuously monitored and correction factors are adjusted based on measured phase and amplitude deviations. UE feedback regarding beamforming quality enables iterative refinement of calibration parameters across the antenna array
2Measurement precision
If calibration procedures are performed to correct phase and amplitude mismatches, then beamforming accuracy is improved, but system complexity and processing overhead increase
Solution Approach 1:
The calibration function is extracted as a separate, dedicated procedure distinct from normal beamforming operations. Calibration reference signals and correction calculations are performed independently, allowing the main beamforming system to reuse calibrated parameters without real-time complexity
Solution Approach 2:
The system changes calibration parameters (phase shifts, amplitude weights) based on pre-determined correction factors rather than continuously adjusting them. This parameter-based approach simplifies the calibration system by converting complex real-time adjustments into lookup-table-style parameter applications
3Area of stationary object
If transmit power is increased to compensate for calibration errors, then coverage is improved, but energy consumption and interference increase
Solution Approach 1:
The system changes the calibration parameters (phase and amplitude weights) applied to each antenna element to correct mismatches rather than uniformly increasing transmit power. This maintains coverage area through constructive interference at target locations while avoiding excessive energy consumption and interference
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Wireless communications systems and methods related to mitigation of calibration errors are provided. A base station (BS) transmits, via an antenna array including a plurality of antenna elements, a first communication signal using a first number of the plurality of antenna elements and a first transmission power level to a user equipment (UE). The BS receives from at least one UE, a measurement report based on the first communication signal. The BS transmitting a second communication signal using a second number of the plurality of antenna elements and a second transmission power level based on the one or more measurement reports. At least one of the first number of the plurality of antenna elements is different from the second number of the plurality of antenna elements, or the first transmission power level is different from the second transmission power level. Other aspects and features are also claimed and described.