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According to the characteristics of the encounter between terminal-sensitive projectile and metal target and the signal processing circuit of millimeter-wave (MMW) alternating current radiometer, a novel method of MMW active jamming based on waveform deception is proposed. An antenna temperature model for the interference source detection is analyzed and established. The antenna temperature signal has wider pulse width and constant amplitude compared with the output signal in ground metal target detection. Then the signal frequency is distorted by the inherent low-frequency cut-off feature of the video amplifier in the radiometer, generating the split signals of positive and negative pulse waveforms, in which the negative waveform pulse can be used to simulate the output signal in ground metal target detection. The experimental results demonstrate the validity and feasibility of the proposed method, which provides an approach for MMW terminal-sensitive active jamming. [ABSTRACT FROM AUTHOR]

The multiobjective optimization provides an extraordinary opportunity for the finest design of electronic circuits because it allows to mathematically balance contradictory requirements together with possible constraints. In this paper, an original and substantial improvement of an existing method for the multiobjective optimization known as GAM (Goal Attainment Method) is suggested. In our proposal, the GAM algorithm itself is combined with a procedure that automatically provides a set of parameters -weights, coordinates of the reference point -for which the method generates noninferior solutions uniformly spread over an appropriately selected part of the Pareto front. Moreover, the resulting set of obtained solutions is then presented in a suitable graphic form so that the solution representing the most satisfactory tradeoff can be easily chosen by the designer. Our system generates various types of plots that conveniently characterize results of up to four-dimensional problems. Technically, the procedures of the multiobjective optimization were created as a software addon to the CIA (Circuit Interactive Analyzer) program. This way enabled us to utilize many powerful features of this program, including the sensitivity analyses in time and frequency domains. As a result, the system is also able to perform the multiobjective optimization in the time domain and even highly nonlinear circuits can be significantly improved by our program. As a demonstration of this feature, a multiobjective optimization of a C-class power amplifier in the time domain is thoroughly described in the paper. Further, a four-dimensional optimization of a video amplifier is demonstrated with an original graphic representation of the Pareto front, and also some comparison with the weighting method is done. As an example of improving noise properties, a multiobjective optimization of a low-noise amplifier is performed, and the results in the frequency domain are shown. Finally, a necessity of a use of metaheuristic methods at least with a combination with the classical ones is demonstrated. [ABSTRACT FROM AUTHOR]

On the basis of the working principle and circuit response characteristics of the millimeter-wave (MMW) alternating current radiometer, a novel method for waveform jamming is proposed. In this method, a MMW jamming source is used to transmit the narrowband signal as the heat source and then a wide-time signal is obtained through a broadband reception and detection of the radiometer. Next, the wide-time signal excites differential response of low-frequency circuit of the video amplifier to yield the splitting waveform, which is similar to the negative pulse waveform in metal-target detection, therefore achieving detection effect of cold-target from the angle of waveform simulation. Simulation results show that the average similarity of the simulation waveform and the actual waveform is 79.21%, and the processing results of experimental data demonstrate validity and feasibility of the proposed method. [ABSTRACT FROM PUBLISHER]

This paper presents a fast block-matching algorithm based on the normalized cross-correlation, where the elimination order is determined based on the gradient magnitudes of subblocks in the current macroblock. Multilevel Cauchy-Schwartz inequality is derived to skip unnecessary block-matching calculations in the proposed algorithm. Also, additional complexity reduction is achieved re-using the normalized cross correlation values for the spatially neighboring macroblock because the search areas of adjacent macroblocks are overlapped. Simulation results show that the proposed algorithm can improve the speed-up ratio up to about 3 times in comparison with the existing algorithm. [ABSTRACT FROM AUTHOR]

Scalable video coding (SVC) has been standardized as an extension of the H.264/AVC standard. This paper proposes a practical real-time transport protocol (RTP) packetization scheme to transport SVC video over IP networks. In combined scalability of SVC, a coded picture of a base or scalable enhancement layer is produced as one or more video layers consisting of network abstraction layer (NAL) units. The SVC NAL unit header contains a (DID, TID, QID) field to identify the association of each SVC NAL unit with its scalable enhancement layer without parsing the payload part of the SVC NAL unit. In this paper, we utilize the (DID, TID, QID) information to derive hierarchical spatio-temporal relationship of the SVC NAL units. Based on the derivation using the (DID, TID, QID) field, we propose a practical RTP packetization scheme for generating single RTP sessions in unicast and multicast transport of SVC video. The experimental results indicate that the proposed packetization scheme can be efficiently applied to transport SVC video over IP networks with little induced delay, jitter, and computational load. [ABSTRACT FROM AUTHOR]

In video transmission, the compressed signal is extremely vulnerable to bit errors. Error concealment is widely used in video decoder to recover corrupted frames. Due to the use of variable length codes (VLCs), a single bit error in block-based bitstream may propagate to following of this slice. Especially, the effectiveness of error concealment technique relies heavily on correctly locating errors. In this paper an error detector based on syntax and continuity which consists of two stages is proposed. The first stage is to find erroneous slice according to checking constraints imposed on video bitstream syntax or detecting special error patterns. In the second stage, the precise position of the first erroneous macroblock (MB) is found based on the continuity of spatial or temporal data of neighbor MBs. Simulation results demonstrate that the proposed method improves performance of error detection significantly compared with the traditional syntax-based method'. [ABSTRACT FROM AUTHOR]

Elementary electronics building blocks can be configured as a low-cost baseband Doppler simulator for developing the post-detector processing parts such as MTIs and MTDS of millimeter wave pulsed radars employing amplitude and phase channels. The challenge of narrow pulses in conjunction to low Doppler frequencies is handled here by CMOS switches and normal function generator ICs. Test noise is generated with an off-the-shelf radio RF/IF circuit. Wideband video amplifiers are not required. Typical performance figures include pulse widths from 50 ns, target ranges from 0 to ambiguity maximum, target velocities from 0.5 m/s to 500 m/s and PRFs up to 100 kflz. Virtual target RCS can be adjusted as needed in a straightforward way. [ABSTRACT FROM PUBLISHER]

An adaptive threshold with constant false alarm rate (CFAR) property is proposed to be used in a channelized electronic support measures (ESM) system with logarithmic video amplification. For this purpose, two CFAR processors are designed which are in fact modified excision (MEx) and adaptive MEx (AMEx) processors, previously presented by authors, but modified for the logarithmic amplification case. In the case of relatively small variations in the noise power, MEx-LOG/CFAR is proposed. This processor exhibits a good robustness against interfering pulses, which cause the major difficulty in the estimation of noise statistics. In the case of relatively large variations in the noise power, AMEx-LOG/CFAR processor is proposed. Thanks to a feedback loop in its structure, this processor can easily adapt itself with any change in the background noise power to assure the CFAR property and false alarm rate regulation. Furthermore, in the steady state (constant noise power), its detection performance is independent of the noise power. Methods to determine the design parameters of the proposed processors are discussed, and their performance analysis is studied using Monte Carlo simulations. [Copyright &y& Elsevier]

The first complete 70 GHz back end module (BEM) of the coming Planck satellite is described. It includes an H-plane waveguide band pass filter, an InP HEMT amplifier, a diode detector made on 0.1 mm alumina substrate, and video amplifiers. RF parts are designed, manufactured, and measured individually and then the complete BEM is tested. Stringent requirements are set through the mechanical layout of the entire functional unit. Most specifications have already been met with the exception of conversion loss in band ripple which must be further reduced. [ABSTRACT FROM PUBLISHER]

Describes the numerical simulations of the notch-filter test method for intermodulation noise distortion in return path cable television amplifiers. Quadrature amplitude modulation; Intermodulation coefficients; Calculation of return path distortion spectrum and output level limit.

Discusses the development of a variable gain, zero offset, dc coupled video amplifier which uses an operational amplifier with 1.6 GHz gain-bandwidth product. Large input bias currents of wideband operational amplifiers; Increase in the sensitivity of positive polarity diode detectors; Maximum attainable gain-bandwidth product.

A three-channel integrated wideband video IC with the possibility of application in high resolution display of lM pixel was developed. This paper reports first the construction of a wideband voltage amplifier circuit in which a wide output signal dynamic range is obtained. With respect to the construction of this circuit, by compensating for the nonlinearity of the bipolar transistor and the logarithmic compression of the signal voltage, an attempt is made to expand the dynamic range. Moreover, by using an opposite- phase current to cancel the negative resistance component appearing in the input impedance when compensating for the nonlinearity, it was attempted to flatten the frequency characteristic. With the present circuit construction, by overcoming the process limitation of low-voltage tolerance, it was possible to ensure wideband characteristics in excess of 140 MHz. In addition, the wideband suppression method of signal crosstalk appearing between channels as side effects of tracking characteristic improvement due to three-channel integration is reported. By suppressing the influence of common impedance and the differential transmission of each signal, it was possible to suppress lower than -43.6 dB the crosstalk between channels below 100 MHz. By the development of this IC, the miniaturization and lowering of cost of high-resolution display and the improvement of adjustment accuracy and stability characteristics could be achieved. [ABSTRACT FROM AUTHOR]

Presents an object-based coding of stereo image sequences by the use of three dimensional models. Discussion on the use of motion parameters to construct predicted images; Information on the transmission relayed on multiview receiver systems; Discussion on the use of preanalyzed scenes in video productions.