Distributed Antenna Equalization for Broad and Narrow Band Gain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Distributed antenna systems face challenges in maintaining consistent gain over a wide range of frequencies, leading to variations in signal quality and requiring tedious and costly manual adjustments in installations, which affects the Quality of Service (QoS) and Quality of Experience (QoE) for users.
Innovation Solution
The system employs a distributed antenna system with a base station interface, signal generators, a master controller, and equalizers to generate test signals and adjust frequency response and gain, using digitally controlled attenuators for final adjustments, enabling automated calibration of both broad and narrow band channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If manual adjustment of power for each DAS element is performed to compensate for inadequate frequency response, then gain consistency over the frequency range is improved, but installation time and cost increase significantly
Solution Approach 1:
The system performs self-calibration by automatically measuring its own frequency response characteristics and adjusting the power of DAS elements without requiring manual intervention. The calibration unit generates test signals, measures the frequency response, and controls power adjustments autonomously, eliminating the need for tedious manual field adjustments while achieving gain consistency across the frequency range.
Solution Approach 2:
The system performs frequency response calibration during the manufacturing or setup phase before actual operation begins. By pre-adjusting the power of each DAS element based on measured frequency response characteristics, the system eliminates the need for subsequent manual adjustments during installation and operation, saving significant time while ensuring gain consistency.
2Ease of manufacture
If factory adjustment of DAS elements is performed to set pre-determined average gain and flat frequency response, then manufacturing complexity is reduced, but field performance adequacy deteriorates
Solution Approach 1:
The system transitions from static factory-set fixed gain values to dynamic, adaptive power adjustment. The calibration unit continuously or periodically measures the actual frequency response and adjusts the power of each DAS element accordingly, allowing the system to adapt to variations in installation conditions, component tolerances, and environmental factors that cannot be accounted for in factory settings alone.
Solution Approach 2:
The system implements a feedback loop where the frequency response is measured, compared against target specifications, and used to control power adjustments to DAS elements. The calibration unit generates test signals, measures the actual frequency response, and uses this feedback information to automatically adjust element powers, ensuring field performance meets requirements regardless of factory adjustment limitations.
3Reliability
If maximum output power is set at frequencies with maximal gain to stay within transmission power regulations, then compliance with power regulations is ensured, but QoS and QoE performance deteriorate at frequencies with lower gain
Solution Approach 1:
The system changes the power parameter of individual DAS elements based on their frequency response characteristics. By identifying elements with lower gain at specific frequencies and increasing their output power accordingly, the system compensates for frequency-dependent variations while maintaining overall compliance with transmission power regulations. This ensures consistent QoS across the frequency range rather than optimizing for peak frequencies only.
Data Source
AI summary
A wireless communications system having at least one RIM associated with a remote unit. The RIMs and the remote units (RU) are configured for transmitting and receiving test signal over at least one narrow band of frequencies. The system includes a plurality of signal generators associated with a signal path, each signal generator configured for generating a test signal over the at least one narrow band of frequencies; a controller configured to generate a test signal for the signal path; and, an equalizer for adjusting gain for the signal path according to at least one of the narrow band of frequencies.