Dual-Stream Dual Carrier Modulation With Cross-Stream Frequency Diversity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing communication technologies, such as Dual Carrier Modulation (DCM), are limited to single spatial stream transmissions, leading to reduced communication range and transmission reliability when extended to multiple spatial streams.
Innovation Solution
Implementing an enhanced frequency diversity scheme across multiple spatial streams, including mapping of modulation symbols to multiple subcarriers and data rate adjustments, indicated by specific information in the signal preamble, to support multiple stream transmissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If Dual Carrier Modulation is extended to multiple spatial streams, then spatial diversity is added to transmission, but communication range and transmission reliability are reduced
Solution Approach 1:
The patent applies parameter changes by modifying the modulation scheme parameters when multiple spatial streams are detected. Specifically, when multiple spatial streams are identified, the system switches from standard DCM to enhanced frequency diversity scheme with mapping of modulation symbols to multiple subcarriers, and adjusts data rate parameters to maintain reliability while utilizing the additional spatial diversity.
2Reliability
If mapping of modulation symbols to multiple subcarriers is applied across multiple spatial streams, then frequency diversity is improved, but device complexity increases
Solution Approach 1:
The patent implements dynamics by making the modulation scheme adaptive based on detected spatial streams. The system dynamically switches between different modulation schemes (standard DCM vs. enhanced frequency diversity) depending on whether one or multiple spatial streams are detected, thereby applying complexity only when needed while maintaining simplicity for single-stream transmissions.
Solution Approach 2:
The patent applies preliminary action by detecting the number of spatial streams before executing the modulation mapping. This preliminary detection allows the system to pre-determine whether to use the enhanced frequency diversity scheme with multiple subcarrier mapping or the simpler standard DCM, avoiding unnecessary complexity processing when single spatial stream transmission is detected.
Data Source
AI summary
The present disclosure provides a communication apparatus and a communication method for dual stream dual carrier modulation DCM), the communication apparatus comprising: circuitry, which, in operation, is configured to set first information indicating whether a mapping of two or more modulation symbols modulated from an information bit of a signal to two or more subcarriers is applied across two or more spatial streams of an orthogonal frequency division multiplexing (OFDM) symbol and second information indicating whether a data rate adjustment is applied to the signal; and a transmitter, which, in operation, transmits the signal with the mapping of the two or more modulation symbols across the two or more spatial streams and/or the data rate adjustment, the signal comprising the first information and the second information.