Super Resolution Time Delay Estimation Based On Narrowband AM Signal

Time-delay estimation (TDE) has wide application in radar, sonar, medical treatment, communication and other fields. It is an active important research area in digital signal processing. TDE problems can be divided into TDEs of single path environment and multipath environment, while the later has practical application background and is a difficult one in TDE problems. TDE in multipath environment also can be divided into basic resolution TDE and super resolution TDE. This thesis focuses on the super resolution TDE in multipath environment.Firstly, we briefly review the development and applications of TDE methods and introduce several TDE methods, such as, the typical method, The generalized correlation method and so on. We focus on the correlation method in this thesis.AM broadcast signal is a narrowband signal, because of the carrier frequency is far higer than the interval frequency. AM signal is not only a 1th order cyclostationary signal but also a 2th order cyclostationary signal.Nonlinear least square method (NLS) has widely used in digital signal processing. WRELAX method works in frequency domain. We have a new method which words in time domain. We simulate their performance in Gaussian noise. The simulation results show that the proposed method works faster than WRELAX.Through the work of this thesis, we systematically analyze some existing algorithms and make these TDE algorithms suitable for application. It also makes these algorithms easy to be used in the HF channel detecting system.