Abstract: The present disclosure provides a method, a system, and a storage medium for benchmarking-based intelligent analysis of an exam paper. The method includes the following steps: building a curriculum standard knowledge point database by analyzing the subject curriculum standard; and inputting an exam paper by using an image acquisition device, recognizing the exam paper by calling an optical character recognition (OCR) algorithm, building a mathematical model of the exam paper and comparing it with the curriculum standard knowledge base, and generating a personalized study condition diagnosis report. The present disclosure can objectively evaluate how well the examinees master the subject knowledge, so as to provide data support for the examinees to formulate a personalized flexible study plan.

Abstract: There is provided an apparatus and method for performing unique word detection and frequency offset estimation for a receiver for DPSK signals comprising in-phase I and quadrature Q components for a plurality of symbols k. The apparatus comprises: a differential detector for performing differential detection of a received signal over a given symbol span; a frequency corrector for performing an initial correction of I and Q using a previously estimated value of the frequency offset; accumulators for averaging I and Q for each symbol k over a given number K of symbols, where K is the number of symbols in the unique word to be detected; a frequency offset estimation block for calculating an estimate of the frequency offset from averaged I and averaged Q; and a unique word detection block for determining, from differentially detected I, differentially detected Q, averaged I and averaged Q, whether or not the unique word is present in a received signal.

Abstract: There is provided an apparatus and method for estimating frequency offset for a receiver for DPSK signals comprising in-phase I and quadrature Q components for a plurality of symbols k. The apparatus comprises a differential detector for performing differential detection of a received signal over a symbol span of n symbols, where n is an integer greater than 1, a frequency corrector for performing an initial correction of I and Q using a previously estimated value of the frequency offset, a rotation block for rotating the phase of each symbol towards zero; and a calculator for calculating an estimate of the frequency offset by comparing the phase of each symbol with zero, the calculator being arranged to input the estimate into the frequency corrector for improving the previously estimated value of the frequency offset.