油毡 发表于 2025-3-25 04:48:53
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,Thesenförmige Zusammenfassung,two cases, the carrier is assumed to be a relatively high frequency sinusoid, the amplitude or frequency of which is modulated in sympathy with the instantaneous value of the signal . (.): and in the other two examples, . (.) is made to modulate either the width or the height of successive pulses in a pulse-train.不能平静 发表于 2025-3-25 11:58:17
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Gewalt und Tod in den Black Hills (Dakota),en used to convey information throughout recorded history, and both Greeks and Romans employed light beacons in the pre-Christian era. A chain of beacons was used by the English in 1588 to warn of the approaching Spanish Armada, and about this time the word ‘signal’ came into general use to denote ‘palette 发表于 2025-3-26 07:12:55
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https://doi.org/10.1007/978-3-658-14239-1ntly. In recent years such signals have come to assume great importance because of developments in digital electronics and computing. Since it is not possible to feed continuous data into a digital (as opposed to analogue) computer, any signal or data input must be represented as a set of numericalhauteur 发表于 2025-3-26 19:52:29
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