Hierarchical Modulation Constellation for Single-Carrier Channels
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Solution Overview
Problem
Existing wireless communication systems face challenges in simultaneously transmitting multiple communication channels with disparate error rate requirements using single-carrier waveform formats, as existing approaches like joint coding and time-division multiplexing do not provide complete solutions for effective simultaneous multiple channel transmission.
Innovation Solution
The system employs hierarchical modulation by coding multiple channels individually and combining them into a single-carrier waveform, using a hierarchical modulation constellation with configurable energy ratios to determine the resilience of bits, allowing for simultaneous transmission of channels with different error rate requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple communication channels with disparate error rate requirements are transmitted simultaneously using single-carrier waveform format, then channel transmission efficiency is improved, but transmission reliability deteriorates due to conflicting error rate requirements
Solution Approach 1:
The patent segments the transmission of multiple channels by assigning different modulation constellations to different channels based on their error rate requirements. Each channel is encoded and modulated independently using appropriate constellation diagrams (e.g., QPSK for high reliability, 16QAM for efficiency), allowing simultaneous transmission while maintaining reliability through differentiated protection levels.
Solution Approach 2:
The patent applies local quality by tailoring the modulation characteristics to specific channel requirements. Different channels receive different modulation schemes according to their individual error rate needs, rather than using a uniform approach. This allows each channel to be optimized for its specific reliability requirements while coexisting in the same time-frequency resource.
2Reliability
If hierarchical modulation with configurable energy ratios is used, then transmission reliability is improved through redundancy, but device complexity increases
Solution Approach 1:
The patent implements nested doll by organizing multiple modulation constellations within a hierarchical structure. The hierarchical modulation scheme nests different constellation diagrams (QPSK, 16QAM, 64QAM) within a unified framework where inner and outer codes are layered. This nested structure provides redundancy and improved reliability while managing complexity through systematic organization of the modulation layers.
Solution Approach 2:
The patent applies parameter changes by using configurable energy ratios to adjust the relative power allocation between different modulation layers. By varying the energy distribution parameter, the system can optimize the balance between reliability and complexity, allowing flexible adaptation to different channel conditions without requiring complete redesign of the modulation scheme.
3Reliability
If individual coding with multiple Zadoff-Chu sequences is used, then transmission reliability is improved, but ease of operation deteriorates
Solution Approach 1:
The patent applies universality by creating a single hierarchical modulation framework that can handle multiple channels with different error rate requirements using a unified approach. Instead of requiring separate coding schemes for each channel type, the system uses a universal hierarchical structure that accommodates various modulation modes (QPSK, 16QAM, 64QAM) within one consistent framework, simplifying the multiplexing operation.
Data Source
AI summary
System(s) and method(s) are provided to transmit simultaneously a first and a second communication channel in a single-carrier waveform format with disparate error rate requirements. First channel and second channel are coded individually to form an alphabet for a first and second constellation. Prior to transmission, bits of information of the first and second channels are modulated with a hierarchical modulation constellation is generated through a combination of a first a second constellation; each constellation is assigned a configurable weight (e.g., a “hierarchic weight”) that is expressed in terms of a configurable energy ratio. The energy ratio determines the resilience of bits associated with the first and second channel. Bit mapping within the first and second constellation provides redundancy to mitigate error rate within each quadrant of the hierarchical constellation. Hierarchical modulation of more than two channel can be accomplished through the same principal of individual coding and constellation composition.