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Apparatus for and method of overhead reduction in a block cipher
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Method of connecting a scrambler or encryption device to a hand-held portable cellular telephone
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Method and apparatus for generating truly random numbers
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Apparatus and method for concealing data bursts in an analog scrambler using audio repetition
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Apparatus and method for providing proper microphone DC bias current and load resistance for a telephone
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Apparatus and method for determining the presence and polarity of direct current bias voltage for microphones in telephone sets
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Apparatus and method for accurate synchronization with inbound data packets at relatively low sampling rates
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Method and apparatus for performing frequency spectrum inversion
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Apparatus and method for secured control of feature set of a programmable device
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Carrier based data operated squelch
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Method and apparatus for providing voice privacy in electronic communication systems
