Research On Adaptive Digital Beamforming And Apply On Radar

Adaptive array (AA) technique is one of the branches in array signal processing. It has played important roles in both military and commercial application fields, such as radar, communication, sonar, navigation, acoustics and speech signal processing, and so on. Especially, it has become a key technique in adaptive active phased array multifunction radars and smart antennas for mobile communication systems. With about half a century's development, numbers of scholars have made great progress in AA techniques. Nowadays, AA has become applied in real systems. However, the research in this field is far from perfect. The array signal adaptive digital beamforming is studied in this thesis. The common DBF algorithms and error model are summarized in the article and the method of suppressing the main-beam disturb and stationary interferers is investigated. This thesis analyses the application of virtual transformation in array signal and the adaptive pattern control is studied. This article has mainly studied the secondary lobe cancellation system in radar anti-active jamming application. First was brief has outlined the auto-adapted numeral beam forming elementary knowledge and the radar under disturbance environment performance analysis. Explained the principle which the auto-adapted secondary lobe cancels.Next studied one kind to be suitable specially for the secondary lobe cancellation system auto-adapted channel compensating process. In view of the channel frequency band characteristic nonuniformity to the auto-adapted array performance influence, the multianalysis tradition auto-adapted channel compensating process shortcoming, proposed one kind based on the band width division free time auto-adapted channel compensating process. This method through the band width division, causes each innertube the unbalance ripple number to drop greatly, thus can real-time and realizes the auto-adapted channel compensation well in channel unbalance ripple number many situations. And disappears for the free time two-dimensional auto-adapted secondary lobe the system design provides the theory basis.Finally studies the phased-array radar technology an important constituent -auto-adapted side lobe to disappear, in view of the conventional radar which carries on is installing the auto-adapted secondary lobe to disappear the (ASLC) system topic, has given the free time two-dimensional auto-adapted secondary lobe disappears the system design, and has designed one based on the monolithic TMS320C6711 chip auto-adapted processor, this processor design enable the system to obtain the big simplification. A kind of algorithm and architecture are described which have specific application to high performance, digital, adaptive beamforming. Adaptive sidelobe cancellation is a important part of phase array radar. To realize low sidelobe and suppressing the interferer the antenna technique and signal process are combined.