Research And Implementation Of Wideband Vector Signal Analysis Technology

Wideband vector signal analysis(VSA) techno logy, which plays a significant role in some industry areas, has beco me a hot research with the rapid development o f broadband wireless digital communication. In recent years, the transmissio n rate and bandwidth o f signal improve cont inuously, which result in the difficult y of wideband vector signal analysis. Nowadays, the do mest ic research in wideband vector signal analysis techno logy is st ill immature, and related instruments rely mainly on expensive imports. Therefore, the study on wideband vector signal analysis techno logy is extremely important.In order to realize the wideband VSA system for MPSK, three key techno logies such as timing synchronizat ion, carrier synchronizat ion and blind equalizat ion, are studied in the dissertat ion respect ively. First ly, the equivalent baseband mathematical model is established, which lays the foundat ion for the research. Secondly, the t iming synchronization techniques are discussed. Considering the requirements o f stabilit y and est imat ion precisio n in wideband VSA, four nonlinear-transformat ion error-est imat ion algorithms and three interpolat ion-filtering error-correction algorithms are studied. The SLN est imat ion algorithm with the best stabilit y as well as highest accuracy, and the cubic interpolat ion filter with the least BER are used in the wideband VSA based on the result. Thirdly, the carrier synchronization techniques are discussed. To so lve the problem of large frequency-o ffset est imat ion-range and realize high precisio n, an improved jo int frequency synchronizat ion algorithm is put forward. Meanwhile, the M-Power phase-offset estimation algorithm is analyzed. The research shows that the proposed algorithm can achieve large est imat ion-range as well as high accuracy simultaneously, and the accuracy o f M-Power algorithm is very high. Forthly, three blind equalizat ion algorithms are studied. Aiming at the stringent requirements of convergence properties and phase correct ion abilit y in wideband VSA, the opt imal MMA algorithm is selected to apply in the system. Finally, this paper builds a complete wideband VSA system for MPSK based on the research above, which is tested by the actual data. The results show that the system presented in this paper meets the requirements, and the performance is equivalent to Agilent 89600 VSA under the same condit ion s.