HS-DSCH Code Multiplexing for 64QAM HARQ Bit Combination
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Solution Overview
Problem
The existing High Speed Downlink Shared Channel (HS-DSCH) technology, based on Code Division Multiple Access (CDMA), faces challenges in meeting increasing demands for broader transmission bandwidth and higher speeds due to limitations in multi-path interference, and cannot effectively support higher-order modulations like 64QAM.
Innovation Solution
The proposed solution involves a method and system for coding and multiplexing in HS-DSCH that allows for 64QAM by rearranging data in a memory space as 6 rows for HARQ bit combination, using specific Redundancy Version parameters, and dividing bit sequences for interleaving through interleavers, along with constellation rearrangement to balance bit reliability and improve transmission quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If CDMA-based HS-DSCH technology is used, then high spectral efficiency and downlink transmission speed are achieved, but the system cannot meet broader transmission bandwidth and higher transmission speed demands due to multi-path interference limitations
Solution Approach 1:
The patent changes the fundamental modulation parameter from CDMA to OFDM, enabling the system to support broader bandwidth (up to 20MHz) and higher transmission speeds (100-200Mbps) by eliminating multi-path interference limitations through orthogonal frequency division multiplexing technology
2Reliability
If existing HS-DSCH coding and multiplexing is used, then 2m TTI bears at most one data block with standard channel coding, but the system cannot support higher-order modulations like 64QAM
Solution Approach 1:
The patent introduces dynamic adaptability by enabling the system to switch between different modulation orders (QPSK, 16QAM, 64QAM) based on channel conditions, and implements dynamic rate matching and HARQ parameters adjustment to support higher-order modulations while maintaining transmission reliability
Solution Approach 2:
The patent changes the channel coding rate and HARQ parameters dynamically according to the selected modulation order, allowing the system to optimize transmission parameters for 64QAM mode with higher coding rates and adjusted redundancy versions to maintain reliability while supporting higher spectral efficiency
3Device complexity
If standard interleaving and physical channel mapping is used, then existing channel structure is maintained, but transmission performance cannot be enhanced for 64QAM mode
Solution Approach 1:
The patent segments the bit sequence into multiple sequences for separate interleaving processing, and divides the physical channel into multiple resource blocks with different mapping patterns optimized for 64QAM, thereby improving spectral efficiency and peak rates while managing complexity through structured segmentation
Solution Approach 2:
The patent introduces constellation rearrangement in the signal domain as an additional processing dimension beyond traditional time-domain interleaving, optimizing the spatial arrangement of constellation points for 64QAM to enhance transmission performance through multi-dimensional signal processing
Data Source
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AI summary
The present invention provides a method for coding and multiplexing in high speed downlink shared channel, comprising: writing data to be combined in a memory space that is arranged as 6 rows by column in turn when implementing 64 Quadrature Amplitude Modulation (QAM) Hybrid Automatic Repeat Request (HARQ) bit combination; and reading out the data from the memory space by column; wherein the data of each column are read out in a particular order. The technical scheme provided in the present invention can use 64 QAM based on the HS-DSCH code multiplexing technology, therefore, the transmission performance for HS-DSCH is improved.