Tensor-Modulated Random Access for Reliable Mixed Demodulation
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Solution Overview
Problem
Conventional random-access communication methods suffer from inadequate communication reliability and limited support for the number of transmitters or users due to sub-optimal spectral efficiency and channel utilization, especially in systems using pilot-based methods.
Innovation Solution
A transmitting device employs tensor-based modulation combined with coherent modulation, splitting the input message into two parts and encoding them differently to generate rank-1 tensor structures, using Kronecker products and precoding matrices for improved spectral efficiency and channel estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If coherent demodulation is used for the first message part, then demodulation accuracy is improved, but receiver complexity increases due to requiring local oscillator synchronization
Solution Approach 1:
The message is divided into two parts: first message part using coherent demodulation for high accuracy, and second message part using non-coherent demodulation for simplicity. This segmentation allows each part to use the most appropriate demodulation method for its requirements.
Solution Approach 2:
Different demodulation methods are applied to different parts of the message based on local requirements. The first part (critical information) uses coherent demodulation with local oscillator synchronization for high accuracy, while the second part (less critical information) uses simpler non-coherent demodulation.
2Device complexity
If non-coherent demodulation is used for the first message part, then receiver complexity is reduced, but demodulation accuracy deteriorates
Solution Approach 1:
The message is divided into two parts: first message part using coherent demodulation for high accuracy, and second message part using non-coherent demodulation for simplicity. This segmentation allows each part to use the most appropriate demodulation method for its requirements.
Solution Approach 2:
Different demodulation methods are applied to different parts of the message based on local requirements. The first part (critical information) uses coherent demodulation with local oscillator synchronization for high accuracy, while the second part (less critical information) uses simpler non-coherent demodulation.
3Productivity
If tensor based modulation is applied to the first message part, then spectral efficiency is improved, but signal detection complexity increases
Solution Approach 1:
The message is divided into two parts: first message part using coherent demodulation for high accuracy, and second message part using non-coherent demodulation for simplicity. This segmentation allows each part to use the most appropriate demodulation method for its requirements.
Solution Approach 2:
Different demodulation methods are applied to different parts of the message based on local requirements. The first part (critical information) uses coherent demodulation with local oscillator synchronization for high accuracy, while the second part (less critical information) uses simpler non-coherent demodulation.
4Productivity
If higher order modulation schemes are used, then data rate is improved, but error rate increases due to reduced noise margin
Solution Approach 1:
The message is divided into two parts: first message part using coherent demodulation for high accuracy, and second message part using non-coherent demodulation for simplicity. This segmentation allows each part to use the most appropriate demodulation method for its requirements.
Solution Approach 2:
Different demodulation methods are applied to different parts of the message based on local requirements. The first part (critical information) uses coherent demodulation with local oscillator synchronization for high accuracy, while the second part (less critical information) uses simpler non-coherent demodulation.
Data Source
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AI summary
A transmitting device for random access communication, includes an encoding circuit configured to encode an input message into a first sequence of bits and a second sequence of bits, split the first sequence of bits into d blocks of bits and determine d vectors. The transmitting device includes a first mapping circuit configured to construct a first symbol vector by computing a Kronecker product of the d vectors and a second mapping circuit configured tomap the second sequence of bits to a second symbol vector. The transmitting device includes a concatenation circuit configured to concatenate the first symbol vector and the second symbol vector into a baseband symbol vector, a modulation circuit configured to modulate the baseband symbol vector to generate a modulated symbol vector comprising modulated symbols, and an antenna configured to transmit each modulated symbols of the modulated symbol vector in a radio frequency signal to a receiving device. The transmitting device combines tensor-based modulation with coherent modulation and hence, manifests an enhanced communication reliability and spectral efficiency.