Modulation Recognition And Parameter Estimation Of Mpsk Signals

The automatic classification and identification of communication signals is an important issue in communication field and has been widely used in both military and civilian systems, such electronic warfare, Intelligence reconnaissance, radio resource management, disaster prevention, etc. Digital communication signals have many advantages, for example, anti-interference, high security, etc. Phase shift keying signal as one of the most important digital modulated signal is applied to many fields. The blind parameter estimation and automatic identification of several commonly-used phase modulated signals is discussed in this dissertation.This dissertation begins with the introduction of the signal parameter estimation and modulation recognition research background and significance, briefly introduces the related theories and algorithms.This dissertation gives the modulation process of MPSK signals and analyses the basic features of BPSK, QPSK, OQPSK, UQPSK and8PSK signals with the help of constellation graph specifically, especially the QPSK, OQPSK and UQPSK signals. For the estimation of snr, power spectrum estimation method, two order moment four order moment estimation method are discussed in short. This dissertation discusses the autocorrelation matrix singular value decomposition algorithm in detail and presents an improved scheme.This dissertation introduces several automatic identification methods and their limitations, including constellation diagram method, phase histogram method, etc. At the end of the dissertation, based on the higher order cumulant theory, we designed a recognition scheme, simulation results show that the scheme has good performance.