Whitepapers

LTE ARQ and Re-segmentation

Re-segmentation effectively enables more flexibility in the LTE eNB scheduling of resources. Instead of rigidly maintaining constant resource constraints for re-sending data, the eNB can quickly and efficiently change resource grants to suit the radio conditions, thereby balancing the resource needs of all users of that eNB.
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Theoretical Analysis on Attenuation of the 5 GHz Miniaturized GaAs MMIC Bandpass Filter

A theoretical analysis method on attenuation of the compact GaAs MMIC bandpass filter using the structure of a diagonally short-ended coupled-line with capacitive loading, which is a potential solution to achieve extremely miniaturized size, is given in this paper. Based on this model, the factors related to the insertion loss performance are investigated. The experimental verification shows good agreement between theory and experiment. The proposed scheme can be used in the design and optimization of this kind of new miniaturized bandpass filter.
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Flex Your Backhaul Network with Adaptive Coding and Modulation

Adaptive Coding and Modulation (ACM) was designed to help operators maximize spectrum usage and increase the capacity of their backhaul links over any given channel bandwidth, under any weather condition, at any link budget. This paper provides an introduction to ACM and offers a number of examples that show how the technology simplifies mobile network planning and helps operators achieve better results both in the field as well as on their balance sheets.
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Optimization of a C-band Pulse Altimeter

In this paper, parameters of an old technology altimeter are discussed. Then, after deriving the measure of quality factor (height measurement accuracy), suitable solutions for improving the technology, namely decreasing its peak power (from 62.5 to 10.9w) to improve its LPI characteristics while maintaining its performance quality, are presented. In this altimeter, by interchanging older microwave devices such as a traveling-wave tube (TWT) with newer solid state devices, quality and LPI characteristics of these systems are improved despite the reduction in their size and cost. Therefore, access to systematic parameters of a pulse altimeter with low power, smaller weight and dimensions, higher security and defence capabilities is possible. In this way, it is of special importance to trade off the parameters and select an overall optimum solution.
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