Spatial Modulation Power Allocation for Diversity Gain
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Solution Overview
Problem
Existing multiple input multiple output (MIMO) and multiple input single output (MISO) wireless communication systems using Spatial Modulation (SM) face limitations in achieving optimal transmit-diversity gains and error probability due to uniform power allocation and antenna activation strategies, which restrict their applicability to low-complexity and low-cost settings, and are not fully exploiting the potential of multiple antennas.
Innovation Solution
A method and system that dynamically allocate power between transmitter elements based on optimized power allocation models, considering channel state information and fading conditions, to enhance the error probability and spectral efficiency, while maintaining the simplicity of Spatial Modulation by identifying the active transmitter element and conveying data through both its index and modulated signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If uniform power allocation is used among transmit antennas, then the system maintains simplicity and ease of operation, but the transmit-diversity gains and error probability performance are suboptimal
Solution Approach 1:
The patent changes the power allocation parameter from uniform to non-uniform distribution among transmit antennas. By optimizing the power allocation vector based on channel state information, the system achieves better error probability performance while maintaining manageable complexity through systematic optimization approaches.
Solution Approach 2:
The patent introduces dynamic power allocation that adapts to varying channel conditions. The power allocation strategy is adjusted based on real-time channel state information, allowing the system to optimize performance for different fading scenarios and spatial correlation conditions.
2Reliability
If antenna activation/de-activation strategies are used, then the spatial constellation pattern can be optimized, but the transmit-diversity gains are limited and the system cannot fully exploit multiple antennas
Solution Approach 1:
The patent changes from binary antenna activation to continuous power allocation across all antennas. By optimizing the power distribution vector, the system achieves higher transmit-diversity gains while maintaining spectral efficiency through improved utilization of all available transmit elements.
Solution Approach 2:
The patent applies different power levels to different transmit antennas based on their individual channel conditions. This localized optimization allows each antenna to contribute optimally to the overall system performance, maximizing transmit-diversity gains while maintaining high spectral efficiency.
3Device complexity
If only one transmit antenna is activated at a time, then the system complexity is reduced, but the diversity order remains equal to one even with multiple transmit antennas
Solution Approach 1:
The patent changes from single-antenna activation to multi-antenna simultaneous transmission with optimized power allocation. By allowing multiple antennas to transmit with different power levels and using advanced detection algorithms, the system achieves higher diversity order while keeping detector complexity manageable through systematic approaches.
Solution Approach 2:
The patent extends the spatial modulation concept from single-antenna selection to multi-antenna power distribution. By adding the power allocation dimension to the spatial domain, the system achieves higher diversity order while maintaining the fundamental spatial modulation detection approach.
4Productivity
If spatial modulation is used to convey information through antenna index, then spectral efficiency is improved, but the system does not fully exploit the potential of multiple antennas for transmit-diversity
Solution Approach 1:
The patent merges spatial modulation with optimized power allocation strategies. By combining the antenna index information conveyance with power-based spatial signature optimization, the system simultaneously achieves high spectral efficiency and enhanced transmit-diversity capabilities.
Solution Approach 2:
The patent optimizes the power allocation parameters to enhance both spectral efficiency and transmit-diversity. By carefully designing the power distribution vector, the system maximizes the information conveyed through antenna selection while simultaneously exploiting multiple antennas for diversity gains.
Data Source
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AI summary
A method of spatial modulation and associated transmission apparatus, receiver apparatus, computer program product and system for identifying a transmitter element within a transmission array of at least two transmitter elements, wherein a signal is transmitted by one active transmitter element at a time over a channel to a receiver. Power is allocated to the transmitter elements, wherein the power is allocated differently between at least two transmitter elements. The transmitted data is received at the receiver. The location of the active transmitter element is detected using knowledge of the power allocated to the transmitter elements.