In this paper, a quarter circular sector with an inverted L shaped monopole antenna for tri-band applications is proposed. The antenna is designed from a U shaped ultra-wideband (UWB) antenna. The number of higher-order modes, each with wide bandwidth, gets excited in a monopole, which electromagnetically couple to provide UWB. In the proposed tri-band antenna the electromagnetic coupling between higher-order modes is reduced by selectively removing the symmetrical portion and decreasing the thickness of the UWB radiator. An inverted L strip is added to a quarter circular sector, and a similarly shaped parasitic element is placed close to the radiator to achieve the desired tri-band. The antenna provides S 11 ≤ −10 dB over 2.1-2.5 GHz, 5.0-5.6 GHz and 8.4-9.0 GHz which covers 3G, Wi-Fi, LTE, Bluetooth, WLAN, and X-band applications. The antenna offers nearly omnidirectional radiation pattern in the lower band and directional radiation pattern in the other two bands. The prototype antenna is fabricated on a 0.147λ 0 × 0.22λ 0 FR4 substrate, where λ 0 is the free-space wavelength corresponding to 2.1 GHz. The measured results agree with simulation ones.
In this paper, dual-band split ring monopole antenna structures for 5G sub-6 GHz and WLAN applications are proposed. The antenna structures are designed from a rectangular annular ring monopole antenna. A compact dual rectangular split ring monopole antenna is designed to operate over dual bands. The two split rings are connected through a common arm. The structure is optimized to provide S 11 ≤ −10 dB over 3.3-3.6 GHz and 5.15-5.5 GHz for 5G and WLAN applications. In the second dual-band antenna, a slot is cut in one of the arms to form another closed rectangular ring to further reduce the dimensions of the antenna. This structure provides S 11 ≤ −10 dB over 3.3-3.6 and 5.5-5.9 GHz for 5G, WLAN and V2X applications. The two bands can be easily controlled as the dimensions of two rings determine the resonant frequencies of the two bands, and one of the arms of a ring is unresponsive to lower band and affects upper band only. Both antennas offer nearly omnidirectional radiation patterns in both bands. The two prototype antennas are fabricated on a 0.17λ 0 × 0.19λ 0 and 0.15λ 0 × 0.19λ 0 FR4 substrate, where λ 0 is the free-space wavelength corresponding to 3.3 GHz. The measured results agree with the simulated ones.
Abstract-A new approach to index color images using the features extracted from the error diffusion Block truncation coding (EDBTC). I. INTRODUCTIONContent-based image retrieval (CBIR), also known as query by image content (QBIC) "Content-based" means that the search examines the contents of the image comparatively than the metadata such as keywords, tags, or descriptions related with the image.In this situation might refer to colors, shapes, textures, or any other information that can be derived from the image itself. CBIR is needed because searches that depend on purely on metadata are dependent on explanation quality and completeness. Having humans manually explain images by entering keywords or metadata in a large database can be time consuming and may not capture the keywords wanted to describe the image.These image retrieval systems involve two phases, indexing and searching, to retrieve a set of similar images from the database, the indexing phase extracts the image features from all of the images in the database which is advanced stored in database as feature vector. In the searching phase, the retrieval system originates the image features from an image submitted by a user (as query image), which are later utilized for performing similarity matching on the feature vectors stored in the data-base. The image retrieval system finally proceeds a set of images to the user with a specific similarity criterion, such as color similarity and texture similarity. Error diffusion is a type of half toning in which the quantization residual is distributed to Neighboring pixels that have not yetbeen processed. Its main use is to convert a multi-level image into a binary image.Block Truncation Coding, or BTC,[22] is a type of lousy image compression technique for greyscale images. It divides the original images into blocks and then uses a quantiser to reduce the number of grey levels in each block at the same time as maintaining the same mean and Standard deviation. A pixel image is divided into blocks of classically 4x4 pixels. For each block the Mean and Standard Deviation of the pixel values are calculated; these statistics generally change from block to block. The pixel values selected for each restored, or new, block are chosen so that each block of the BTC compressed image will have (approximately) the same mean and standard deviation as the corresponding block of the original image
Before there was an art of abstract painting, it was already widely believed that the value of a picture was a matter of colors and shapes alone. Music and architecture were constantly held up to painters as examples of a pure art which did not have to imitate objects but derived its effects from elements peculiar to itself. But such ideas could not be readily accepted, since no one had yet seen a painting made up of colors and shapes, representing nothing. If pictures of the objects around us were often judged according to qualities of form alone, it was obvious that in doing so one was distorting or reducing the pictures; you could not arrive at these paintings simply by manipulating forms. And in so far as the objects to which these forms belonged were often particular individuals and places, real or mythical figures, bearing the evident marks of a time, the pretension that art was above history through the creative energy or personality of the artist was not entirely clear. In abstract art, however, the pretended autonomy and absoluteness of the aesthetic emerged in a concrete form. Here, finally, was an art of painting in which only aesthetic elements seem to be present.
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