FBMC Transmit Diversity Using Frequency-Domain Precoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Combining Filter Bank-based Multi Carrier (FBMC) technology with Alamouti encoding is challenging due to the impact of imaginary part interference, which cannot be effectively addressed without using a guard interval, leading to low system efficiency.
Innovation Solution
A specific data encoding method is employed, where data matrices are processed and mapped onto antennas in a manner that eliminates imaginary part interference without a guard interval, using precoding matrices and Alamouti encoding to generate FBMC signals for transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a guard interval is added in the time domain to eliminate imaginary part interference in FBMC combined with Alamouti encoding, then the reliability of transmission is improved, but the system efficiency deteriorates due to the large guard interval required
Solution Approach 1:
The patent transitions from time-domain guard interval insertion to frequency-domain precoding matrix application. By applying the precoding matrix W in the frequency domain before FBMC modulation, the system eliminates imaginary part interference without requiring time-domain guard intervals, thus maintaining system efficiency while improving transmission reliability
Solution Approach 2:
The patent changes the approach from temporal parameter (guard interval duration) to frequency-domain parameter (precoding matrix coefficients). The precoding matrix W transforms the data matrices in the frequency domain, fundamentally changing how interference is managed and enabling elimination of imaginary part interference without time-domain extensions
2Reliability
If FBMC is combined with Alamouti encoding to achieve transmit diversity, then the reliability is improved, but the device complexity increases due to the difficulty of combining FBMC with Alamouti encoding
Solution Approach 1:
The patent segments the encoding process into distinct frequency-domain matrix operations. The data is divided into matrices X0 and X1, which are then processed separately through the precoding matrix W before being combined for FBMC modulation. This segmentation simplifies the overall complexity by breaking down the challenging FBMC-Alamouti combination into manageable frequency-domain steps
Solution Approach 2:
The patent replaces the traditional time-domain Alamouti encoding mechanism with a frequency-domain precoding mechanism. Instead of manipulating signals in the time domain as in classic Alamouti, the system uses frequency-domain matrix multiplication with precoding matrix W, which is better suited to FBMC's frequency-domain nature and reduces implementation complexity
Data Source
AI summary
The present invention provides an FBMC transmit diversity transmission method and apparatus. The method includes: obtaining a to-be-transmitted data sequence, where the to-be-transmitted data sequence includes 2*M*N pieces of data; performing transmit diversity processing on the to-be-transmitted data sequence to obtain FBMC signals of a first antenna and a second antenna, where a precoding matrix is (I) or (II), a matrix that includes the FBMC signals of the first antenna and the second antenna is (III), a matrix that includes the to-be-transmitted data sequence is (IV), 0≤i≤M−1, 0≤j≤N−1, Y=WX, the 2*M*N pieces of data of the to-be-transmitted data sequence are denoted by x(0)(k,l) and x(1)(k,l), 0≤k≤M−1, 0≤l≤N−1, FBMC signals of the first antenna and the second antenna on an rth subcarrier and an sth symbol are denoted by y(0)(r,s) and y(1)(r,s), 0≤r≤2M−1, and 0≤s≤N−1; and transmitting the FBMC signals of the first antenna and the second antenna.