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Because of daily life natural or unnatural accidents, the Vehicular Ad-Hoc Network (VANET) is one of the affecting areas for the enhancement of Intelligent Transportation System (ITS) for facilitating road safety, traffic management and entertainment services for drivers and passengers. Vehicular networks can help avoid accidents by warning drivers of forthcoming risks or prompting embedded systems to respond autonomously. Multi-hop wireless connectivity and frequently changing network topology in VANET are the factors to plan effective and efficient dynamic routing protocols. While these studies are anticipating, designing protocols for vehicular networks has many challenges. The current routing protocols for VANET are not sufficiently effective to meet all traffic situations. Therefore Creditable routing protocols are required to start correspondence between vehicles in future for passengers and road security and safety. This paper demonstrates literature study related to some of the Topology-based investigated VANETs routing protocols in the light of premise of their characteristics and operations and additionally their qualities and shortcomings. Furthermore a few proposals are made to accomplish change in execution of these protocols.

In modern warfare of the complex electromagnetic environment, varieties of communications, radar and other interference signals accumulate with high density. So the receiver with large instantaneous bandwidth, high sensitivity and multiple signals simultaneously processing characteristics is required. Poly-phase filter structure can not only reduce system complexity, but also process the channel data parallelly and improve the system efficiency. Discrete Fournier transformation(DFT) modulated filter banks with near perfect reconstruction(NPR) solve the problem of unknown signals across the channels. Using the FPGA as the core chip, the design of eight reconfigurable channelized receiver is completed to combine the poly-phase filter and DFT modulated filter banks. Then do the simulation by the softwares of ISE13.3, Modelsim10.1 and Matlab2010. The system simulation results meet the design requirement and show its engineering application value.

Related automatic dependent surveillance(ADS) is one kind of Air Traffic Control(ATC) surveillance technology has been well developed by the international civil aviation organization. In order to satisfy both management and monitoring of the general aviation and commercial aviation, the system uses 1090 ES and UAT double data link mode system model to. This paper puts forward a kind of ADS-B digital receiver system design scheme based on the 1090 ES and UAT data link. Using ADS simulation software, the RF front-end system, power splitters and low noise amplifier modules are simulated. Then this paper verified these modules through the way of multi-module converter and making the sheet of the PCB. At last, the field test verifies the effectiveness of the receiver, and achieves higher receiver sensitivity, dynamic range and other technical indicators.

With the development of radio communication technology, more higher demands are proposed on signal fidelity, accuracy of frequency and stability of amplitude in order to improve the performance of communication system. As one of the most important measure instruments in lab and other researches, the performance of signal generator will directly affect the measurement results of communication system and design ideas. Therefore signal generator needs more functions and accurate measurements to meet higher standard requirements. This paper introduces a way to realize four kinds of modulation shift modes: sine wave, 2ASK, 2FSK and 2CPFSK based on DDS which is controlled by FPGA and a wide setting range of frequency and amplitude.

Demodulation technology is the most critical signal processing functionality in the communication system. Using efficient digital demodulation can improve the transmission performance of communication system. This paper introduces the principle of Continuous Phase Frequency Shift Keying (CPFSK) and its demodulation. And then designs the CPFSK demodulator by using the orthogonal differential demodulation algorithm based on software defined radio. Later, the paper deals with the structure of the demodulator. Finally, the demodulator is realized on the XC6SLX25 provided by Xilinx. The result confirms the feasibility of the all-digital CPFSK demodulator.

EEG (Electroencephalogram) signals recording the brain activities which carry abundant physiological and pathological information, have great significance in the research. However, it mixed with a variety of artifacts, special the EOG (Electrooculogram), that affect the judgment, removing the artifact is of great meaning. Blind Source Separation (BSS) is popular in signal processing recently, many methods are applied to remove artifacts from EEG signals, such as Second Order Blind Identification (SOBI), Wavelet Transform (WT) and Independent Component Analysis (ICA). Stone's method is to use two different linear filters which process the same set sources, here first use to remove the EOG artifact in EEG signals, it is also a new field for the stone algorithm application. Then compared with two classical algorithms, determine the superiority of the proposed algorithm, finally give the conclusion.

A new robust beamforming algorithm with worst case performance against the steering vector mismatch for near-field is presented. For uniform linear array, the model of near-field signal with spherical wave-front has been used to design the beamforming problem. The convex optimization method is applied to revise the steering vector error of the beam, and the algorithm constraints on the source signal to minimum the output variance of the signal, and maximum the output SINR. The output performance of the steering vector mismatch problem has been improved, and it's simple to implement. Results of simulation for a 10-element uniform linear array verify the availability and effectiveness of this robust method.

Distributed video coding is under the requirements of simple coding and complex decoding as the rapid development of microelectronics, communication and computer technology. This paper presents a method to improve the system of distributed video coding. Compressive sensing theory and distributed video coding are combined to generate a new system named distributed video coding based on compressive sensing to reduce the system's computational complexity and improve the compression efficiency, the process of encoder is a process of projecting the high-dimension signal to the low dimension space and the intra frame encoding at the same time, the decoder is solving owe qualitative equations and intra frame decoding simultaneously. Simulation results indicate that the proposed method can greatly reduce the sampling rate and the decoding complexity. The method can also get better quality video images of reconstruction.

In this paper, neural network group is proposed to improve the performance of discrete wavelet neural network group (DWNNG) for automatic digital modulation recognition (ADMR). The neural network group can reduce the complexity of only one neural network. The neural network can be easier to be trained with low errors by using neural network group. The problem of local optimum can be improved. And the system can recognize more modulations. The experiment indicates that it can recognize 2ASK, 4ASK, 8ASK, 2FSK, 4FSK, 8FSK, 2PSK, 4PSK, 8PSK, 4QAM and 16QAM. The mean correct recognition rates were obtained 95.7% by using neural network group substitute for single one.

Agile frequency signal has already been the self-navigation signal of new torpedo, because of its excellent anti-interference ability. Target echo signal of torpedo contains a lot of object signal information. It is important to research the torpedo's target echo signal, when the agile frequency signal is the transmitted signal. The paper introduces a target echo signal model, appointting to the agile frequency signal. In the model, agile frequency signal is the transmitted signal of the target simulator hardware system. Moreover, the character of the target echo has been discussed in detail. Also the mathematic model of agile homing torpedo's target echo signal has been constructed. The simulation steps of the Doppler frequency shift, delay, ocean environment noise and reverberation have been discussed in detail and are simulated in Matlab. The simulation proves that simulating target echo signal of agile homing torpedo by hardware is feasible.