Millimetre wave imaging systems are widely used in many fields, such as non-destructive testing, security screening and medical imaging. For security-related personnel screening, the geometries of planar and cylindric...
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Millimetre wave imaging systems are widely used in many fields, such as non-destructive testing, security screening and medical imaging. For security-related personnel screening, the geometries of planar and cylindrical-scanning antenna arrays are often adopted. A planar array imager is capable of acquiring a three-dimensional image in real time, but the information on the back side of the object will be lost. A cylindrical scanning imager is well suited for constructing an image in full 360 degrees directions, what is lost is the time that it takes to complete a full scan. Regardless, mechanical scanning geometry is not always the best approach for real-time systems. In this letter, an imaging scenario is proposed, which is composed of two parallel arrays facing each other. multipleinputmultipleoutputtechnology is applied to the pair of arrays. Range migration algorithm is adapted specially for this scenario, through which nearly 360 degrees-images of high quality can be constructed in real time when an object is placed between the two arrays.
Wireless sensor network's (WSN's) and wireless personal area network technologies continue to develop rapidly with integration into numerous applications. The ever increasing demands on these systems require t...
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Wireless sensor network's (WSN's) and wireless personal area network technologies continue to develop rapidly with integration into numerous applications. The ever increasing demands on these systems require that radio transceivers extend their coverage area and adopt more efficient algorithms to full fill the requirements of new applications. In this study, a unique application of multiple-input multiple-output technology is applied to the application of WSN's in order to dynamically extend range and thus overall coverage area. The scheme incorporates multiple antennas with dual circular 32-quadrature amplitude modulation for multi-band orthogonal frequency division multiplexing-based systems in order to increase the wireless communication range. Simulations results are then presented that show a significant improvement in the system performance in terms of the bit error rate and also signal-to-noise power ratio.
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