OFDM Symbol Timing for Precise Ranging and Positioning
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Solution Overview
Problem
Existing OFDM-based wireless communication systems face challenges in achieving precise ranging, angle measurement, and positioning due to synchronization phase errors, leading to inaccuracies in measurement results.
Innovation Solution
Implementing fixed intervals between signal transmission and reception start points for OFDM symbols to reduce synchronization errors, allowing for precise channel estimation and correction of measurement results, thereby improving the accuracy of ranging, angle measurement, and positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If OFDM signal processing is used for wireless communication, then communication speed and data transmission capability are improved, but synchronization phase errors are introduced leading to poor measurement precision
Solution Approach 1:
The patent applies preliminary action by pre-calculating and setting fixed time intervals (first preset duration and second preset duration) between signal transmission and reception. This predetermined timing arrangement allows the receiving device to accurately determine when to sample the incoming OFDM signal, compensating for synchronization phase errors before they degrade measurement precision. The fixed intervals are established in advance to align the receiving window with the actual signal arrival time.
Solution Approach 2:
The patent changes the time parameter by introducing fixed duration intervals between transmission and reception operations. Instead of using arbitrary or dynamically adjusted timing, the system employs predetermined time offsets (first preset duration for transmitter, second preset duration for receiver) that are carefully selected to compensate for known synchronization delays in OFDM processing, thereby improving measurement accuracy.
2Ease of operation
If any point in the cyclic prefix of an OFDM symbol is used as the receiving start point, then operation flexibility is improved, but synchronization errors increase leading to large measurement errors
Solution Approach 1:
The patent applies local quality by designating a specific, optimized receiving start point within the cyclic prefix region rather than allowing arbitrary selection. The fixed second preset duration is calculated to position the receiving window at the optimal location where synchronization phase errors are minimized. This localized optimization of the receiving start point maintains operational simplicity while significantly improving measurement precision.
Solution Approach 2:
The patent uses preliminary action by pre-calculating the optimal receiving start point position (second preset duration) before signal transmission. This predetermined timing offset is established based on expected synchronization delays, allowing the receiving device to be pre-configured with the correct sampling window position, thereby eliminating the need for dynamic adjustment while achieving high precision.
3Measurement precision
If fixed intervals are implemented between transmission and reception time points, then synchronization error is reduced improving measurement precision, but system complexity increases due to precise timing control requirements
Solution Approach 1:
The patent changes the timing parameters by introducing fixed duration intervals (first preset duration and second preset duration) that are carefully calculated to compensate for synchronization delays. These parameter changes transform the timing control from a complex dynamic adjustment system into a simpler fixed-offset system, reducing the computational burden while maintaining high measurement precision.
Solution Approach 2:
The patent applies self-service by having each device (transmitter and receiver) independently apply its own fixed time offset (first preset duration for transmitter, second preset duration for receiver) to its operations. This decentralized approach eliminates the need for complex centralized timing coordination, allowing each device to autonomously compensate for synchronization errors using predetermined values, thereby reducing overall system complexity.
Data Source
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AI summary
A communication system, a communication processing method, and a related apparatus are provided. The communication system includes a first node and a second node. The first node is configured to send a first OFDM symbol to the second node, where a sending start time point of the first OFDM symbol is a first time point. The second node is configured to receive the first OFDM symbol, where a receiving start time point of the first OFDM symbol is a second time point. The second node is configured to start to send a second OFDM symbol to the first node at a third time point, where there is an interval of first preset duration between the third time point and the second time point. The first node is configured to start to receive the second OFDM symbol at a fourth time point, where the fourth time point serves as a receiving start time point at which the first node receives the second OFDM symbol, and there is an interval of second preset duration between the fourth time point and the first time point. The first OFDM symbol and the second OFDM symbol are used for ranging, angle measurement, or positioning. According to embodiments of this application, measurement precision can be improved.