CPRI IQ Data Mapping for Multi-Standard Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CPRI protocol methods face challenges in efficiently supporting multi-standard IQ signal transmission and switching due to differences in sampling frequencies and bit widths, leading to complex resource requirements and significant delays in aligning IQ data frames across various standards in a mixed-mode application scenario.
Innovation Solution
A method and apparatus that map IQ data of multiple standards onto a CPRI radio frame with aligned multi-frames, where each multi-frame consists of K basic frames and identical IQ sub-container bit widths, allowing for efficient switching and transmission by using a uniform K-chip period and Naxc bit width, independent of the standard, and incorporating filling fields for non-integer frequency ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple standards with different sampling frequencies and bit widths are transmitted using existing CPRI methods, then multi-standard transmission capability is achieved, but device complexity and resource requirements increase significantly
Solution Approach 1:
The patent applies homogeneity by mapping IQ data from multiple standards with different sampling frequencies and bit widths into a unified CPRI frame structure. All standards use the same frame format, same bit width Naxc for IQ sub-containers, and same positioning rules, eliminating the need for standard-specific processing complexity in intermediate nodes.
Solution Approach 2:
The patent creates a universal mapping method that can handle WCDMA, WIMAX, CDMA, and other standards through a single CPRI frame structure. The AxC container block can accommodate IQ data from any standard by adjusting the mapping parameters (K, Naxc, positioning) while maintaining the same underlying transmission mechanism, making the system multi-functional without requiring separate handling for each standard.
2Reliability
If IQ data frames of different standards are aligned using existing methods, then timing synchronization is achieved, but transmission delays increase significantly
Solution Approach 1:
The patent applies preliminary action by pre-defining the positions of IQ sub-containers for multiple standards within the CPRI frame structure before transmission. The mapping relationships between different standards and their positions in the frame are established in advance through parameters K and Naxc, allowing intermediate nodes to perform simple switching without complex real-time alignment operations, thus reducing delays.
Solution Approach 2:
The patent uses parameter changes to adapt the mapping for different standards. By adjusting parameters such as K (number of basic frames per AxC container block), Naxc (bit width of IQ sub-containers), and positioning offsets, the system can accommodate different sampling frequencies and bit widths while maintaining synchronized frame structures, avoiding the need for time-consuming runtime alignment.
3Reliability
If standard-specific IQ mapping methods are used for each standard, then optimal performance for each standard is achieved, but ease of operation and switching capability deteriorate
Solution Approach 1:
The patent segments the IQ data from different standards into separate AxC container blocks within the unified CPRI frame structure. Each standard's IQ data is mapped to specific containers with defined positions, allowing the receiving end to extract and process each standard independently while the intermediate nodes can perform simple switching based on container positions, thus maintaining both optimization and ease of operation.
Data Source
AI summary
The invention provides a method for IQ data mapping, including the following steps of: mapping IQ data of one or more standards to a CPRI radio frame, wherein, the CPRI radio frame includes multiple multi-frames, and boundaries of the multi-frames are aligned with the header of the CPRI radio frame, and each multi-frame includes K basic frames, and each basic frame includes a plurality of IQ sub-containers, and one IQ sub-container constitutes one time slot, and the number K of the basic frames and bit widths Naxc of the IQ sub-containers included in each multi-frame are identical for different standards, and the length of the CPRI radio frame is 10ms. The invention also provides an IQ data mapping apparatus.