The Detection Of DSSS Of Cyclic Spectrum Based On Multichannel Maximum Entropy Spectrum Estimation

This subject is derived from national fund program: The main work of this subject is to research the detection of DSSS and estimate of parameter partially. As communication in battle is the integration of various technologies, one of the purpose of the subject is that we can detect the existence of signal from background noise, another purpose is we can imply the estimation of parameter and interfere every load wave point in different circumstances, for example in the situation DS-FH and even TH. That means we need a more effective and efficiency method of detection and parameter estimation to detect the existence of signal, even in the situation of short sampling sequencies. This writing expound the technology of cyclic spectrum which detect DSSS. According to survey, the universal method is periodic diagram method which is apply for detect DSSS. As we know that, the advantage of periodic diagram is we can receive effective detection result which based on the assumption of enough data and hardware memory. However, the inherent defect can not be ignored. For example, if the data is not enough or too short, the estimated spectrum will be more warped and specrtum resolution will become lower. Thus, in order to achieve exact calculation, enormous samplings are prerequisite in practice. Obviously, this method can not be used in effective and efficiency manner.In response to this defect, this writing put forward modern estimation method--,multichannel BURG estimation to estimate cyclic spectrum. As a sort of AR specrtum estimation, BURG avoid the disadvantage of brought by FOURIER transform. Moreover, compare to Levenson, BURG can calculate the parameter of AR Model directly from signal observation Data, Auto-Relation function become not necessary in this new method. Avoiding the calculation of Auto-Relation function, the estimation of the merit of BURG for short sampling data sequence is more accurate than Levenson. This character of BURG is very suitable in practice which provides possibility of communication counterwork in battlefield. Although the specrtum peak would be split under estimation of sine wave. Althouth a suitable theory is needed to reponse to sovle the related disadvantages.