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A new airborne MTI scheme that applies to non-homogeneous clutter environment is presented. Results of simulation have proved that the scheme has a superior ground clutter suppression performance and can effectively prevent the whitening of a target.

Electronic devices are getting more and more sensitive to the electro-static discharge (ESD) because of their smaller size and higher frequency. An electronic dictionary device studied here has failed in the ESD immunity test according to the IEC61000-4-2 standard. Many factors which could impact on the ESD immunity performance of the device are investigated in the test and some suggestions are also given in this paper for improving its performance. The improving suggestions are listed and analyzed combining the device in detail in this paper: 1) improving the ESD immunity performance of the dictionary's PCB; 2) changing the outer package material for the dictionary, protecting the LED; and 3) building a complete ESD test system. The device has gained a significant improvement on the ESD immunity by using merely part of our suggestions. We hope that this could be a reference to the manufactures of similar devices as well

This paper advances an Electrostatic Discharge Displacement Current (ESDDC) which will ?flow? through the space to all the victim devices on the EUT when discharge occurs and the ESDDC contributes to the failure of the equipment besides the discharge current and the electromagnetic field radiated from the ESD. Experiments were performed to test the ESDDC. The results show that the ESDDC is one of the major characters of the electrostatic discharge..

A method for evaluating the robustness of constant false alarm rate (CFAR) detectors is presented, which is based on the powerful methodology of influence function (IF) developed in the literature on robust statistics. It can evaluate and compare the robustness of different kinds of CFAR detectors by calculating the first derivative of false alarm probability (FAP) at an underlying distribution, which is named FAP-IF. The FAP-IF of cell averaging (CA) and ordered statistics (OS) CFAR detectors are presented. The computational simulation of radar detection in exponential clutter is also presented to prove the theoretical result.

In this paper, the relationship of subarray size, snapshot number and interference number is studied for different gradient computing methods. New forward and backward CGM (FBCGM) and multilayer FBCGM (MFBCGM) methods are proposed. Their advantages are summarized as follows: (1) they can be applied with a small number of snapshots. (2) They can be applied with a weaker constraint for the number of the array elements than that Mandyam (1997). (3) They perform well in coherent receiving environments. (4) They have less computational load compared to SMI and the subspace projection method.

In order to improve the clearness of images captured at night, a new enhancement algorithm is proposed in this paper. Its characters are: (1) enhancing the dark image with contrast enhancement and histogram equalization in series, so both the local and global information can be used; (2) a contrast transforming function which is suited to deal with dark image is proposed; (3) it can be realized in real time. The new method shows good performance in dealing with night vision images.

Conventional tracking radars are often embarrassed when targets being tracked are flying at low altitude over a flat surface. The basic idea for conventional low-angle tracking techniques is to avert the multipath interference by shielding the antenna from the surface reflection or by eliminating the reflection component from the received signal. This is the most direct way to deal with the well-known multipath effect. A new algorithm using a different idea is presented, with which the signal from the reflecting surface can be used to enhance that directly from the target, resulting in extended accuracy, applicability and efficiency. The estimation of the target elevation angle is expressed as the geometric mean of the target and its image's angles relative to the boresight axis. Implementation of the algorithm is quite simple.

Based on the fact that the result of noncoherent integration of the amplitudes of independent samples of noise is approximately identical to nonzero-mean Gaussian distribution, a Gaussian biparametric constant false alarm rate (GB-CFAR) processor is presented, which is a novel CFAR detector independent of original clutter plus noise distribution. Then the conclusion is presented that its detection performance relates only to the false alarm rate, the number of integration and the mean-to-standard-deviation ratio of original noise. Eliminating the mean of integrated noise amplitude during the detection process is equivalent to taking out partial noise energy, therefore, the detection performance of the GB-CFAR processor exceeds that of the traditional CA-CFAR (cell-averaging CFAR) processor.

In this paper, the leading characters, parallelism, programmability, scalability and reconfigurability of next generation high speed real-time radar signal processing systems are discussed in detail. Important design issues are studied. An experimental system underway is introduced.

Moving target detection (MTD) is a high-performance signal processing approach for pulse Doppler radar. High-performance radar calls for sliding MTD (SMTD). Traditional SMTD processing massively increases computational load, resulting in difficulty of implementation. A modified moving DFT algorithm and a new SMTD structure are proposed in this paper. The new SMTD structure adopts both batch-mode signal channel estimation and the modified moving DFT algorithm, which leads to a dramatic reduction of the computational load. The new SMTD structure can be regarded as an adaptive filter for other applications as well.

In this paper, the leading characters, parallelism, programmability, scalability and reconfigurability of next generation high speed real-time radar signal processing systems are discussed in detail. An experimental system underway is introduced.

A new tracking algorithm is proposed. It treats the target acceleration as a nonrandom term, and consists of a constant velocity filter an input estimator and a maneuver detector implemented in parallel. The new method has the same advantages as the two-stage Kalman estimator which requires a lesser amount of computation and provides even a better performance when compared with an augmented state Kalman filter. At the same time, the new method uses a better tuning parameter and removes a difficulty in implementation of the two-stage Kalman estimator. It is shown that the new filter is a better alternative to the two-stage Kalman estimator on tracking maneuvering targets.