Symbol packet detecting method of OFDM (Orthogonal Frequency Division Multiplexing) carrier communication module for automatic meter reading systems

The invention discloses a symbol packet detecting method of an OFDM (Orthogonal Frequency Division Multiplexing) carrier communication module for automatic meter reading systems. According to the method, aiming at the noise and interference characteristics of a power line channel and the characteristics of an OFDM power line carrier communication module signal, the main characteristic energy and the main characteristic vector of the receipt signal of an OFDM carrier communication module receiver are sequentially estimated by adopting a recursive least-squares algorithm on the basis of eigen-space decomposition; the symbol packet is detected by utilizing the difference of the main characteristic energy with or without the OFDM signal; and therefore, on the premise of not increasing the frame redundancy of the OFDM signal, the symbol detecting accuracy is increased, the operation complexity is reduced and the method is easy to realize and apply.