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The limitation of microstrip patch antenna is relatively low gain and narrow bandwidth. By using the microstrip patch antenna array antenna performance can be improved. In this paper design and stimulation of a 4 element rectangular microstrip patch array is described and the performance of antenna array is optimized by varying patch element dimensions. Antenna array is designed to operated at the frequency of 10 GHz. The corporate-series feed network is implemented for feeding patch elements. The 2x2 antenna array is implemented on FR4 substrate with 1.588mm thickness and dielectric constant of 4.4.The stimulation and performance analyze of antenna is done using Ansoft High frequency structure simulator software. Finally, comparison of antenna array characteristics before and after optimization is presented.

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When it is desired to transmit redundant data over an insecure and bandwidth-constrained channel, it is customary to first compress the data and then encrypt it. In this paper, we investigate the efficiency of reversing the order of these steps, i.e., first encrypting and then compressing, without compromise for compression efficiency or the informationtheoretic security. A pseudorandom permutation and a linear encoding scheme is used to encrypt an original image, and the encrypted data are efficiently compressed by discarding the excessively rough and fine information of coefficients generated from orthogonal transform. After receiving the compressed data, based on spatial correlation, a receiver can reconstruct the principal content of the original image by iteratively updating the values of coefficients and the linear decoding procedure.