Phase Synchronization via Amplitude-Based Code Word Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In CDMA systems, phase synchronization between the code word used by a receiving device and the received spread spectrum signal is challenging, leading to channel crosstalk and reduced signal-to-noise ratios, as existing methods fail to effectively determine and adjust phase differences to synchronize the two.
Innovation Solution
A method utilizing a specific code word with a linear relationship between its phase value and the amplitude of the despread signal, where phase synchronization is achieved by determining the phase difference based on amplitude variations of despread signals, allowing for synchronization processing to align the code word phase with the spread spectrum signal phase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If phase synchronization is not achieved between code word and spread spectrum signal, then channel crosstalk is generated and signal-to-noise ratio is reduced, but phase synchronization is difficult to determine and adjust
Solution Approach 1:
The patent replaces complex iterative phase adjustment mechanisms with a direct calculation method based on amplitude measurements. By substituting the mechanical/iterative synchronization process with a mathematical calculation using amplitude values and code word phases, the system achieves phase synchronization without complex feedback loops or trial-and-adjustment mechanisms.
Solution Approach 2:
The patent introduces an intermediary calculation method that uses amplitude values of despread signals as a mediator to determine phase differences. Instead of directly measuring or iteratively adjusting phase, the system uses amplitude measurements combined with known code word phases to calculate the required phase adjustment, simplifying the synchronization process.
2Reliability
If existing phase synchronization methods are used, then synchronization processing is complex and time-consuming, but phase alignment is required to avoid crosstalk
Solution Approach 1:
The patent applies preliminary action by pre-storing code word phases and using them directly in the phase difference calculation. Instead of iteratively searching for the correct phase alignment, the system uses known code word phase information in advance to directly calculate the required adjustment, significantly reducing synchronization time while maintaining accuracy.
Solution Approach 2:
The patent replaces time-consuming iterative phase adjustment mechanisms with a direct calculation method. By substituting the mechanical/iterative synchronization process with a mathematical calculation using amplitude values and pre-stored code word phases, the system achieves rapid phase synchronization without complex feedback loops.
3Measurement precision
If phase difference is not accurately determined, then synchronization processing cannot be performed effectively, but accurate phase measurement is challenging
Solution Approach 1:
The patent introduces an intermediary calculation method that uses amplitude values as a mediator to indirectly determine phase differences. Instead of directly measuring phase (which is difficult), the system measures amplitude (which is easier) and combines it with known code word phases to calculate the phase difference, achieving accurate measurement while reducing detection difficulty.
Solution Approach 2:
The patent replaces difficult direct phase measurement with a calculation-based approach. By substituting direct phase detection with a mathematical calculation using amplitude measurements and code word phase information, the system achieves accurate phase difference determination without the complexity of direct phase measurement.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method and an apparatus for phase synchronization are disclosed. The method includes: receiving, by a receiving device, a spread spectrum signal transmitted by a transmitting device (31); despreading, by the receiving device, the received spread spectrum signal by using a specific code word, to obtain a first despread signal, where an amplitude value of the first despread signal is a first amplitude value (32); adjusting, by the receiving device, a phase value of the specific code word, and despreading the received spread spectrum signal by using the phase-adjusted specific code word, to obtain a second despread signal, where an amplitude value of the second despread signal is a second amplitude value (33); determining, by the receiving device, a first phase difference according to a difference between the first amplitude value and the second amplitude value (34); and performing, by the receiving device, synchronization processing between a phase value of the phase-adjusted specific code word and a phase value of the received spread spectrum signal by using the first phase difference (35).