Switching Timing Detection in Distributed Antenna Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In distributed antenna systems, accurately detecting the switching timing between uplink (UL) and downlink (DL) signals is challenging, leading to potential interference and degradation of communication quality, especially when using the LTE TDD scheme, as existing methods are complex and prone to errors due to signal variations.
Innovation Solution
A distributed antenna system with a slave station apparatus that includes a rising edge detector, symbol detector, and switching timing detector, which uses correlation calculations and normalization to accurately determine the switching timing between UL and DL signals, allowing for precise timing detection without complicating the apparatus configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the beginning of UL or DL signal is detected based on switching timing estimated from configuration information, then the detection method is simple, but the detection accuracy is insufficient and apparatus becomes complicated due to decoding requirements
Solution Approach 1:
The patent extracts only the necessary timing information from the received signal by detecting the rising edge of the signal envelope, rather than decoding the entire configuration information. This extraction approach achieves accurate timing detection without requiring complex decoding apparatus, thus resolving the contradiction between detection accuracy and apparatus complexity
Solution Approach 2:
The patent introduces a correlation calculation as an intermediary process between signal reception and timing detection. By calculating the correlation between the received signal and a reference signal, the system can accurately identify switching timing without directly decoding configuration information, thereby maintaining simple apparatus while achieving high detection accuracy
2Measurement precision
If the beginning of signal is detected using detector output with several microseconds variation, then the detection method is simple, but the detection accuracy is insufficient
Solution Approach 1:
The patent performs preliminary processing of the received signal by calculating its envelope and detecting the rising edge before final timing determination. This preliminary action prepares the signal in a form that is easier to measure accurately, reducing the detection difficulty while improving precision beyond what raw detector output can achieve
3Reliability
If guard time is extended to prevent UL-DL interference, then communication quality is maintained, but transmission efficiency is reduced
Solution Approach 1:
The patent replaces the mechanical approach of extending guard time with a signal processing approach using correlation calculation and rising edge detection. This substitution enables precise timing detection that allows for shorter guard times while maintaining reliable UL-DL switching, thus improving transmission efficiency without sacrificing communication quality
Data Source
AI summary
According to an embodiment, a communication apparatus includes a switching unit, a reception unit, a rising edge detector, a symbol detector, and a switching timing detector. The switching unit switches a transmission operation of a signal in the communication apparatus between uplink signal transmission and downlink signal transmission. The reception unit receives a signal transmitted in a time division multiplexing scheme. The rising edge detector detects a rising edge of a received signal received by the reception unit. The symbol detector detects a symbol of a signal indicating a guard time in the time division multiplexing scheme from the received signal. The switching timing detector detects a switching timing of the transmission operation from the switching unit on the basis of detection results of the rising edge detector and the symbol detector.