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In this paper, a new distributed receiving technology based on time-delay control was proposed. It towards the problem of broad band signal distributed receiving, which are difficult to be realized by phase shifter. Further more, the relation of distributed receiving SNR (signal to noise ratio) and channel number was deduced. And the influence of channel error to distributed receiving performance also was analyzed. Some important simulations were done, which reveal that the theoretical results correspond with simulation results, and main influence factors of distributed receiving are channel number and time-delay error.

To the EW system, the conventional radar signal description is based on radar parameters and their features, which is hard to describe the modern complex radar. A new conception of Pulse Sequence Pattern (PSP), which uses a representative pulse sequence with multi-dimension parameters as the radar signal description, is proposed in this paper firstly. And the PSP of typical radar is described in detail. At last, the fast signal processing algorithm based on the PSP is given. The experiments and computer simulations show that the description of PSP is practicable and the recognition algorithm is more effective than the conventional method.

In order to settle the problem of emitter recognition, the method of feature weights setting which applies variable precision rough set model is researched in this paper. Because this weight setting method is completely decided by data itself, it is more impersonal and practical. The description of object classpsila condition attribute in conception positive region can be used to get the plenary condition of this conception. The weights of feature parameters in emitter recognition can be gained by the dependences between knowledge; at the same time, the fuzzy theory is combined to form an emitter fuzzy recognition method based on feature weight by variable precision rough set model. At last, this mixed method is applied in radar emitter type recognition, simulation and the results show it is effective and feasible.

Adaptive nulling methods with multiple constraints for transmitting digital beamforming (DBF) of uniform linear arrays (ULA) are proposed in the following three circs, with main lobe constraint only, with main and side lobes constraints, with main and side lobes constraints and given nulls constraint. And the optimum weight vector of transmitting DBF is derived by Lagrange multiplier approach and calculated with sample matrix inversion algorithm. The computer simulations show that the proposed methods are practicable and effective.

The millimeter-wave radar can overcome the limit of cloud, fog, dust and observation at night and so on; in addition it has many characteristics such as better resolving power and resolving precision and so on, so the technique of the millimeter-wave radar is being developed recently. It is important to track the maneuvering targets correctly in time, to probe rightly, track, capture in the air, on the sea or on the ground, EKF (extended Kalman filter) arithmetic is feasible in the application of target tracking in 3-dimension space or 2-dimension space, and then simulated, which shows the arithmetic has better robustness and precision, and the tracking effect is better than other tracking methods.

Fractal feature can describe the complexity of radar emitter signal. Wavelet transform cannot only observe signal general framework and detail, but also reduce influence of noise. Hence wavelet transform can combine with the fractal theory to study the fractal feature of radar emitter signal. First, signal is decomposed by wavelet transform, and then fractal dimension is computed in different decomposition levels, so the signals with different complexity have different fractal dimensions. In the end the simulation experiments validate that this method is effective to distinguish radar emitter signal.

There exists many complex targets in battlefield, it is important to track the maneuvering targets correctly on their flight path in time, to probe rightly, track, capture the maneuvering target. EKF arithmetic is applied in 3D space and simulated in computer, in addition the arithmetic is fully verified with better robustness and accuracy, and it can satisfy the modern war demand.

The key techniques of multiple maneuvering targets passive tracking by single observer are discussed. Firstly, a new adaptive passive tracking initiation algorithm based on information fusion is proposed. Secondly, a new data association algorithm is proposed. Based on the information fusion of multiple features, the decision of synthetic data association is made. Finally, with the help of computer simulations, the proposed algorithms are proven to be correct and effective

This work studies the LAN lost-call, having a roundabout route, by the Monte Carlo simulation approach, and simulates it in the computer. Then it comes to a conclusion: when a roundabout route exists, the number of lost-calls decreases enormously, as a consequence, which enhances the counter-destroying performance in a LAN.

Tracking initiation and data association are key techniques of multi-target passive tracking by a single observer. A new adaptive passive tracking initiation algorithm based on information fusion is proposed In this work. First, according to multiple features of the target, a multidimensional dynamically variable tracking gate is built for adaptive detection. Further, the sequential probability ratio test (SPRT) rule is used to confirm the track. And also, a new data association algorithm based on information fusion is proposed. Based on the information fusion of multiple features of a single valid observation, the decision of synthetic data association of all the targets is made. With the help of computer simulations, the tracking initiation algorithm is proven to be correct and effective, and the data association algorithm is proven to be superior to the NN method.

EEG (electroencephalogram) is usually used to analyze brain activity in clinical medicine; it can distinguish the abnormal circadian state from the normal circadian state. The paper presents some chaos time series analysis methods for analyzing the circadian state by the doctor/researcher. The validity of the methods is verified by some related graphs produced by computer simulation, and all these methods hold water in medical application and research.

With the fast development of digital signal processing, network and multimedia techniques, the digital watermark technique is applied extensively in the domains of data information identification and data product authentication. The wavelet transform technique can process the data of speech signal etc., the signal can be decomposed into the low frequency and high frequency part of multi-levels, which can be encrypted by the processing of the digital watermark technique, and will attain the encryption or concealment goal of the speech signal. The paper introduces the wavelet transform and its technical application in digital watermarking in speech signals, and the signals of non-encrypted speech before or encrypted speech after are played and compared.

Under the circumstance of intensive interferences, the detection probability of weak signals and the precision for their DOA estimation would be decreased seriously. A combined algorithm both for anti-jamming and DOA estimation is achieved based on the least mean-square error criterion in this paper. Finally, the results are analyzed theoretically. Computer simulations show its efficiency.

The millimeter wave radar can overcome the limit of cloud, fog, dust and observation at night and so on, in addition it has many characteristics such as better resolving power and resolving precision and so on, so the technique of the millimeter-wave radar is being developed. The millimeter wave radar fills and levels up the gap between the optics and microwave. The millimeter-wave radar has the tradeoff advantages of optics and microwave. So, its characteristics are introduced in the paper, and the performance of the millimeter-wave radar is simulated and studied.

Based on the time difference of arrival (TDOA) and the direction of arrival (DOA) of the non-cooperative illuminators, the interacting multiple-model (IMM) algorithm for passive location of maneuvering target by single fixed station is proposed in this paper. The maneuvering model and the measurement equation are built and the location principle with IMM algorithm is discussed. With the help of computer simulation, the proposed method is proven to be practicable and effective.

A new data association algorithm based on information fusion of multi-feature and multi-target in passive tracking is proposed in this paper. It uses more features of the target such as the frequency, PRI, while the traditional algorithms only use the features directly correlative with the target state such as DOA, TOA. Based on the information fusion of multiple features with DS evidence theory, the decision of synthetic data association of all the targets is made. With the help of computer simulations, it is proven that the proposed algorithm is superior to the NN method and the expanded NN method.