Uplink Downlink Discrimination Using Orthogonal Preambles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing unmanned mobile device systems face challenges in reliably distinguishing between uplink and downlink communications, leading to potential interference and increased computational costs due to the need for demodulation to determine communication types.
Innovation Solution
Implementing a method using time division multiple access (TDMA) with orthogonal preambles for uplink and downlink communications, allowing receivers to determine communication type through convolution with reference preambles without demodulation, thereby reducing computational complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If demodulation is performed to determine communication type, then communication type identification accuracy is improved, but computational cost increases
Solution Approach 1:
The patent extracts the communication type identification function from the demodulation process. Instead of performing full demodulation to determine communication type, the system uses a simplified correlation-based detection method that operates on the received signal directly, separating the identification function from the complex demodulation process and reducing computational requirements
Solution Approach 2:
The patent applies preliminary action by performing correlation detection with reference preambles before committing to full demodulation. The system pre-stores uplink and downlink preamble sequences and performs quick correlation checks to identify communication type in advance, allowing the receiver to prepare appropriate processing parameters before actual data demodulation begins
2Quantity of substance
If uplink and downlink communications share the same frequency band, then spectrum efficiency is improved, but interference between uplink and downlink increases
Solution Approach 1:
The patent segments the communication protocol structure into distinct fields, including separate preamble sequences for uplink and downlink transmissions. By dividing the communication frame into identifiable segments with unique characteristics, the system allows frequency-division duplexing while maintaining clear distinction between uplink and downlink signals through structured protocol design
Solution Approach 2:
The patent introduces preamble sequences as intermediary elements that mediate between uplink and downlink communications sharing the same frequency band. These preambles serve as recognizable markers that allow receivers to identify signal direction and apply appropriate processing, enabling full-duplex operation while managing interference through structured signal design
3Productivity
If multiple unmanned mobile devices communicate simultaneously, then system productivity is improved, but difficulty of detecting and measuring communication type increases
Solution Approach 1:
The patent applies local quality by assigning distinct preamble characteristics to different communication directions (uplink vs. downlink) and potentially different device groups. Each communication type has locally optimized signal properties that make it easily distinguishable, allowing multiple devices to communicate simultaneously while maintaining clear identification of each signal's purpose through localized signal design
Data Source
Figure 1~2
Figure 3~4B
Figure 5~7
AI summary
Method implemented in a system comprising a control station and at least one drone. Each communication of data in said system between the control station and a drone being made in the form of packets, each packet comprising a preamble and being transmitted in a modulated form according to a predefined modulation. The method comprises: using, in each packet communication from the control station to a drone, a preamble, known as the uplink preamble, orthogonal to the preamble, known as downlink preamble, used in each packet communication from a drone to the control station; and, upon receiving a modulated packet, determining whether said modulated packet has been transmitted as a result of uplink or downlink communication in accordance with a result of a convolution between said modulated packet with a reference preamble modulated according to the predefined modulation, said reference preamble corresponding to the uplink preamble or the downlink preamble.