Remote Radio Head Predistortion for Efficient Multi-Band Amplification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Remote Radio Head Units (RRUs) are power inefficient, costly, and inflexible, limiting their ability to support evolving wireless communication standards and increasing data traffic demands, particularly in managing high data-traffic growth and multi-frequency band operations.
Innovation Solution
The implementation of an adaptive digital predistortion algorithm in a hybrid system combining digital and analog modules to linearize RF power amplifiers, enhance power efficiency, and support multi-frequency bands, multi-modulation schemes, and multi-channels, with features like crest factor reduction and self-adaptation algorithms for field reconfigurability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional RF power amplifiers are used in RRUs, then the RRU can provide basic wireless communication functions, but the power efficiency is poor and the DC to RF power conversion is low
Solution Approach 1:
The patent applies digital predistortion techniques that pre-compensate for non-linearities in the power amplifier before the signal is amplified. This preliminary digital processing allows the analog power amplifier to operate more efficiently by reducing the need for excessive back-off, thereby improving DC to RF power conversion efficiency while maintaining signal quality
Solution Approach 2:
The patent replaces traditional analog linearization methods with digital signal processing techniques. By using digital predistortion and adaptive algorithms, the system achieves better power efficiency without relying on complex analog circuitry, thus substituting mechanical/analog approaches with digital ones
2Adaptability or versatility
If traditional RRU architecture is used, then the system can support current wireless standards, but it lacks flexibility for software upgradability and field reconfiguration
Solution Approach 1:
The patent divides the RRU into distinct functional modules including digital signal processing units, analog RF units, and control interfaces. This segmentation allows independent upgrading of digital components through software while keeping the analog RF section unchanged, thereby improving adaptability without proportionally increasing overall system complexity
Solution Approach 2:
The patent designs a universal RRU platform that can support multiple wireless standards and frequency bands through software configuration rather than hardware changes. This multi-functionality approach enables a single RRU device to adapt to evolving standards, improving versatility while avoiding the complexity of maintaining multiple specialized devices
3Adaptability or versatility
If multiple RRUs are deployed to support different frequency bands and standards, then coverage and functionality are improved, but the cost and system complexity increase
Solution Approach 1:
The patent implements a universal RRU design that can operate across multiple frequency bands and support different wireless standards through software reconfiguration. This allows a single RRU device to replace what would traditionally require multiple specialized RRUs, thereby reducing the number of devices needed while maintaining comprehensive frequency band support
Solution Approach 2:
The patent incorporates dynamically reconfigurable components that can change their operating parameters through software control. This dynamic capability allows the RRU to adapt its frequency bands, modulation schemes, and other parameters in real-time, enabling multi-frequency band support with a single device rather than requiring static, dedicated hardware for each band
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
This approach results in higher efficiency and linearity for wideband communication systems, enabling cost-effective and flexible RRU deployments that can adapt to various wireless standards, reducing the need for multiple RRUs and lowering operational costs while improving performance and scalability.
Implementation Method 1
The present invention is a novel RRU system that utilizes an adaptive digital predistortion algorithm. The hybrid system of digital and analog modules both linearize the spectral regrowth and enhance the power efficiency of the PA
Implementation Method 2
The present invention utilizes an adaptive digital predistortion algorithm implemented in a hybrid system of digital and analog modules... at least one feedback sensor associated with each power amplifier for providing a feedback signal
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A multiple-channel remote radio head unit for wireless communications is disclosed, comprising: a plurality of power amplifiers, each receiving an input signal and each providing as an output an amplified representation of the received input signal; a plurality of feedback paths, wherein each feedback path in the plurality of feedback paths provides a feedback signal that includes a representation of a characteristic of a power amplifier of the plurality of power amplifiers; digital logic for processing signals; a feedback switch for selecting one of the feedback signals for connection to the digital logic to generate predistortion compensation signals for each of the plurality of power amplifiers; a plurality of circulators, each coupled to the output of a power amplifier of the plurality of power amplifiers; a duplexer coupled to the plurality of circulators; and a plurality of receiver switches, each coupled to a circulator of the plurality of circulators, that selectively couples a respective circulator to the digital logic to reduce insertion loss between the plurality of power amplifiers and the duplexer.